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|
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include "go_asm.h"
#include "go_tls.h"
#include "funcdata.h"
#include "textflag.h"
TEXT runtime·rt0_go(SB), NOSPLIT|NOFRAME|TOPFRAME, $0
// save m->g0 = g0
MOVD $runtime·g0(SB), runtime·m0+m_g0(SB)
// save m0 to g0->m
MOVD $runtime·m0(SB), runtime·g0+g_m(SB)
// set g to g0
MOVD $runtime·g0(SB), g
CALLNORESUME runtime·check(SB)
#ifdef GOOS_js
CALLNORESUME runtime·args(SB)
#endif
CALLNORESUME runtime·osinit(SB)
CALLNORESUME runtime·schedinit(SB)
MOVD $runtime·mainPC(SB), 0(SP)
CALLNORESUME runtime·newproc(SB)
CALL runtime·mstart(SB) // WebAssembly stack will unwind when switching to another goroutine
UNDEF
TEXT runtime·mstart(SB),NOSPLIT|TOPFRAME,$0
CALL runtime·mstart0(SB)
RET // not reached
DATA runtime·mainPC+0(SB)/8,$runtime·main(SB)
GLOBL runtime·mainPC(SB),RODATA,$8
// func checkASM() bool
TEXT ·checkASM(SB), NOSPLIT, $0-1
MOVB $1, ret+0(FP)
RET
TEXT runtime·gogo(SB), NOSPLIT, $0-8
MOVD buf+0(FP), R0
MOVD gobuf_g(R0), R1
MOVD 0(R1), R2 // make sure g != nil
MOVD R1, g
MOVD gobuf_sp(R0), SP
// Put target PC at -8(SP), wasm_pc_f_loop will pick it up
Get SP
I32Const $8
I32Sub
I64Load gobuf_pc(R0)
I64Store $0
MOVD gobuf_ret(R0), RET0
MOVD gobuf_ctxt(R0), CTXT
// clear to help garbage collector
MOVD $0, gobuf_sp(R0)
MOVD $0, gobuf_ret(R0)
MOVD $0, gobuf_ctxt(R0)
I32Const $1
Return
// func mcall(fn func(*g))
// Switch to m->g0's stack, call fn(g).
// Fn must never return. It should gogo(&g->sched)
// to keep running g.
TEXT runtime·mcall(SB), NOSPLIT, $0-8
// CTXT = fn
MOVD fn+0(FP), CTXT
// R1 = g.m
MOVD g_m(g), R1
// R2 = g0
MOVD m_g0(R1), R2
// save state in g->sched
MOVD 0(SP), g_sched+gobuf_pc(g) // caller's PC
MOVD $fn+0(FP), g_sched+gobuf_sp(g) // caller's SP
// if g == g0 call badmcall
Get g
Get R2
I64Eq
If
JMP runtime·badmcall(SB)
End
// switch to g0's stack
I64Load (g_sched+gobuf_sp)(R2)
I64Const $8
I64Sub
I32WrapI64
Set SP
// set arg to current g
MOVD g, 0(SP)
// switch to g0
MOVD R2, g
// call fn
Get CTXT
I32WrapI64
I64Load $0
CALL
Get SP
I32Const $8
I32Add
Set SP
JMP runtime·badmcall2(SB)
// func systemstack(fn func())
TEXT runtime·systemstack(SB), NOSPLIT, $0-8
// R0 = fn
MOVD fn+0(FP), R0
// R1 = g.m
MOVD g_m(g), R1
// R2 = g0
MOVD m_g0(R1), R2
// if g == g0
Get g
Get R2
I64Eq
If
// no switch:
MOVD R0, CTXT
Get CTXT
I32WrapI64
I64Load $0
JMP
End
// if g != m.curg
Get g
I64Load m_curg(R1)
I64Ne
If
CALLNORESUME runtime·badsystemstack(SB)
CALLNORESUME runtime·abort(SB)
End
// switch:
// save state in g->sched. Pretend to
// be systemstack_switch if the G stack is scanned.
MOVD $runtime·systemstack_switch(SB), g_sched+gobuf_pc(g)
MOVD SP, g_sched+gobuf_sp(g)
// switch to g0
MOVD R2, g
// make it look like mstart called systemstack on g0, to stop traceback
I64Load (g_sched+gobuf_sp)(R2)
I64Const $8
I64Sub
Set R3
MOVD $runtime·mstart(SB), 0(R3)
MOVD R3, SP
// call fn
MOVD R0, CTXT
Get CTXT
I32WrapI64
I64Load $0
CALL
// switch back to g
MOVD g_m(g), R1
MOVD m_curg(R1), R2
MOVD R2, g
MOVD g_sched+gobuf_sp(R2), SP
MOVD $0, g_sched+gobuf_sp(R2)
RET
TEXT runtime·systemstack_switch(SB), NOSPLIT, $0-0
RET
TEXT runtime·abort(SB),NOSPLIT|NOFRAME,$0-0
UNDEF
// AES hashing not implemented for wasm
TEXT runtime·memhash(SB),NOSPLIT|NOFRAME,$0-32
JMP runtime·memhashFallback(SB)
TEXT runtime·strhash(SB),NOSPLIT|NOFRAME,$0-24
JMP runtime·strhashFallback(SB)
TEXT runtime·memhash32(SB),NOSPLIT|NOFRAME,$0-24
JMP runtime·memhash32Fallback(SB)
TEXT runtime·memhash64(SB),NOSPLIT|NOFRAME,$0-24
JMP runtime·memhash64Fallback(SB)
TEXT runtime·return0(SB), NOSPLIT, $0-0
MOVD $0, RET0
RET
TEXT runtime·asminit(SB), NOSPLIT, $0-0
// No per-thread init.
RET
TEXT ·publicationBarrier(SB), NOSPLIT, $0-0
RET
TEXT runtime·procyield(SB), NOSPLIT, $0-0 // FIXME
RET
TEXT runtime·breakpoint(SB), NOSPLIT, $0-0
UNDEF
// func switchToCrashStack0(fn func())
TEXT runtime·switchToCrashStack0(SB), NOSPLIT, $0-8
MOVD fn+0(FP), CTXT // context register
MOVD g_m(g), R2 // curm
// set g to gcrash
MOVD $runtime·gcrash(SB), g // g = &gcrash
MOVD R2, g_m(g) // g.m = curm
MOVD g, m_g0(R2) // curm.g0 = g
// switch to crashstack
I64Load (g_stack+stack_hi)(g)
I64Const $(-4*8)
I64Add
I32WrapI64
Set SP
// call target function
Get CTXT
I32WrapI64
I64Load $0
CALL
// should never return
CALL runtime·abort(SB)
UNDEF
// Called during function prolog when more stack is needed.
//
// The traceback routines see morestack on a g0 as being
// the top of a stack (for example, morestack calling newstack
// calling the scheduler calling newm calling gc), so we must
// record an argument size. For that purpose, it has no arguments.
TEXT runtime·morestack(SB), NOSPLIT, $0-0
// R1 = g.m
MOVD g_m(g), R1
// R2 = g0
MOVD m_g0(R1), R2
// Set g->sched to context in f.
NOP SP // tell vet SP changed - stop checking offsets
MOVD 0(SP), g_sched+gobuf_pc(g)
MOVD $8(SP), g_sched+gobuf_sp(g) // f's SP
MOVD CTXT, g_sched+gobuf_ctxt(g)
// Cannot grow scheduler stack (m->g0).
Get g
Get R2
I64Eq
If
CALLNORESUME runtime·badmorestackg0(SB)
CALLNORESUME runtime·abort(SB)
End
// Cannot grow signal stack (m->gsignal).
Get g
I64Load m_gsignal(R1)
I64Eq
If
CALLNORESUME runtime·badmorestackgsignal(SB)
CALLNORESUME runtime·abort(SB)
End
// Called from f.
// Set m->morebuf to f's caller.
MOVD 8(SP), m_morebuf+gobuf_pc(R1)
MOVD $16(SP), m_morebuf+gobuf_sp(R1) // f's caller's SP
MOVD g, m_morebuf+gobuf_g(R1)
// Call newstack on m->g0's stack.
MOVD R2, g
MOVD g_sched+gobuf_sp(R2), SP
CALL runtime·newstack(SB)
UNDEF // crash if newstack returns
// morestack but not preserving ctxt.
TEXT runtime·morestack_noctxt(SB),NOSPLIT,$0
MOVD $0, CTXT
JMP runtime·morestack(SB)
TEXT ·asmcgocall(SB), NOSPLIT, $0-0
UNDEF
#define DISPATCH(NAME, MAXSIZE) \
Get R0; \
I64Const $MAXSIZE; \
I64LeU; \
If; \
JMP NAME(SB); \
End
TEXT ·reflectcall(SB), NOSPLIT, $0-48
I64Load fn+8(FP)
I64Eqz
If
CALLNORESUME runtime·sigpanic<ABIInternal>(SB)
End
MOVW frameSize+32(FP), R0
DISPATCH(runtime·call16, 16)
DISPATCH(runtime·call32, 32)
DISPATCH(runtime·call64, 64)
DISPATCH(runtime·call128, 128)
DISPATCH(runtime·call256, 256)
DISPATCH(runtime·call512, 512)
DISPATCH(runtime·call1024, 1024)
DISPATCH(runtime·call2048, 2048)
DISPATCH(runtime·call4096, 4096)
DISPATCH(runtime·call8192, 8192)
DISPATCH(runtime·call16384, 16384)
DISPATCH(runtime·call32768, 32768)
DISPATCH(runtime·call65536, 65536)
DISPATCH(runtime·call131072, 131072)
DISPATCH(runtime·call262144, 262144)
DISPATCH(runtime·call524288, 524288)
DISPATCH(runtime·call1048576, 1048576)
DISPATCH(runtime·call2097152, 2097152)
DISPATCH(runtime·call4194304, 4194304)
DISPATCH(runtime·call8388608, 8388608)
DISPATCH(runtime·call16777216, 16777216)
DISPATCH(runtime·call33554432, 33554432)
DISPATCH(runtime·call67108864, 67108864)
DISPATCH(runtime·call134217728, 134217728)
DISPATCH(runtime·call268435456, 268435456)
DISPATCH(runtime·call536870912, 536870912)
DISPATCH(runtime·call1073741824, 1073741824)
JMP runtime·badreflectcall(SB)
#define CALLFN(NAME, MAXSIZE) \
TEXT NAME(SB), WRAPPER, $MAXSIZE-48; \
NO_LOCAL_POINTERS; \
MOVW stackArgsSize+24(FP), R0; \
\
Get R0; \
I64Eqz; \
Not; \
If; \
Get SP; \
I64Load stackArgs+16(FP); \
I32WrapI64; \
I64Load stackArgsSize+24(FP); \
I32WrapI64; \
MemoryCopy; \
End; \
\
MOVD f+8(FP), CTXT; \
Get CTXT; \
I32WrapI64; \
I64Load $0; \
CALL; \
\
I64Load32U stackRetOffset+28(FP); \
Set R0; \
\
MOVD stackArgsType+0(FP), RET0; \
\
I64Load stackArgs+16(FP); \
Get R0; \
I64Add; \
Set RET1; \
\
Get SP; \
I64ExtendI32U; \
Get R0; \
I64Add; \
Set RET2; \
\
I64Load32U stackArgsSize+24(FP); \
Get R0; \
I64Sub; \
Set RET3; \
\
CALL callRet<>(SB); \
RET
// callRet copies return values back at the end of call*. This is a
// separate function so it can allocate stack space for the arguments
// to reflectcallmove. It does not follow the Go ABI; it expects its
// arguments in registers.
TEXT callRet<>(SB), NOSPLIT, $40-0
NO_LOCAL_POINTERS
MOVD RET0, 0(SP)
MOVD RET1, 8(SP)
MOVD RET2, 16(SP)
MOVD RET3, 24(SP)
MOVD $0, 32(SP)
CALL runtime·reflectcallmove(SB)
RET
CALLFN(·call16, 16)
CALLFN(·call32, 32)
CALLFN(·call64, 64)
CALLFN(·call128, 128)
CALLFN(·call256, 256)
CALLFN(·call512, 512)
CALLFN(·call1024, 1024)
CALLFN(·call2048, 2048)
CALLFN(·call4096, 4096)
CALLFN(·call8192, 8192)
CALLFN(·call16384, 16384)
CALLFN(·call32768, 32768)
CALLFN(·call65536, 65536)
CALLFN(·call131072, 131072)
CALLFN(·call262144, 262144)
CALLFN(·call524288, 524288)
CALLFN(·call1048576, 1048576)
CALLFN(·call2097152, 2097152)
CALLFN(·call4194304, 4194304)
CALLFN(·call8388608, 8388608)
CALLFN(·call16777216, 16777216)
CALLFN(·call33554432, 33554432)
CALLFN(·call67108864, 67108864)
CALLFN(·call134217728, 134217728)
CALLFN(·call268435456, 268435456)
CALLFN(·call536870912, 536870912)
CALLFN(·call1073741824, 1073741824)
TEXT runtime·goexit(SB), NOSPLIT|TOPFRAME, $0-0
NOP // first PC of goexit is skipped
CALL runtime·goexit1(SB) // does not return
UNDEF
TEXT runtime·cgocallback(SB), NOSPLIT, $0-24
UNDEF
// gcWriteBarrier informs the GC about heap pointer writes.
//
// gcWriteBarrier does NOT follow the Go ABI. It accepts the
// number of bytes of buffer needed as a wasm argument
// (put on the TOS by the caller, lives in local R0 in this body)
// and returns a pointer to the buffer space as a wasm result
// (left on the TOS in this body, appears on the wasm stack
// in the caller).
TEXT gcWriteBarrier<>(SB), NOSPLIT, $0
Loop
// R3 = g.m
MOVD g_m(g), R3
// R4 = p
MOVD m_p(R3), R4
// R5 = wbBuf.next
MOVD p_wbBuf+wbBuf_next(R4), R5
// Increment wbBuf.next
Get R5
Get R0
I64Add
Set R5
// Is the buffer full?
Get R5
I64Load (p_wbBuf+wbBuf_end)(R4)
I64LeU
If
// Commit to the larger buffer.
MOVD R5, p_wbBuf+wbBuf_next(R4)
// Make return value (the original next position)
Get R5
Get R0
I64Sub
Return
End
// Flush
CALLNORESUME runtime·wbBufFlush(SB)
// Retry
Br $0
End
TEXT runtime·gcWriteBarrier1<ABIInternal>(SB),NOSPLIT,$0
I64Const $8
Call gcWriteBarrier<>(SB)
Return
TEXT runtime·gcWriteBarrier2<ABIInternal>(SB),NOSPLIT,$0
I64Const $16
Call gcWriteBarrier<>(SB)
Return
TEXT runtime·gcWriteBarrier3<ABIInternal>(SB),NOSPLIT,$0
I64Const $24
Call gcWriteBarrier<>(SB)
Return
TEXT runtime·gcWriteBarrier4<ABIInternal>(SB),NOSPLIT,$0
I64Const $32
Call gcWriteBarrier<>(SB)
Return
TEXT runtime·gcWriteBarrier5<ABIInternal>(SB),NOSPLIT,$0
I64Const $40
Call gcWriteBarrier<>(SB)
Return
TEXT runtime·gcWriteBarrier6<ABIInternal>(SB),NOSPLIT,$0
I64Const $48
Call gcWriteBarrier<>(SB)
Return
TEXT runtime·gcWriteBarrier7<ABIInternal>(SB),NOSPLIT,$0
I64Const $56
Call gcWriteBarrier<>(SB)
Return
TEXT runtime·gcWriteBarrier8<ABIInternal>(SB),NOSPLIT,$0
I64Const $64
Call gcWriteBarrier<>(SB)
Return
TEXT wasm_pc_f_loop(SB),NOSPLIT,$0
// Call the function for the current PC_F. Repeat until PAUSE != 0 indicates pause or exit.
// The WebAssembly stack may unwind, e.g. when switching goroutines.
// The Go stack on the linear memory is then used to jump to the correct functions
// with this loop, without having to restore the full WebAssembly stack.
// It is expected to have a pending call before entering the loop, so check PAUSE first.
Get PAUSE
I32Eqz
If
loop:
Loop
// Get PC_B & PC_F from -8(SP)
Get SP
I32Const $8
I32Sub
I32Load16U $0 // PC_B
Get SP
I32Const $8
I32Sub
I32Load16U $2 // PC_F
CallIndirect $0
Drop
Get PAUSE
I32Eqz
BrIf loop
End
End
I32Const $0
Set PAUSE
Return
TEXT wasm_export_lib(SB),NOSPLIT,$0
UNDEF
|
