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// Copyright 2022 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 "textflag.h"
// func memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr)
TEXT runtime·memclrNoHeapPointers<ABIInternal>(SB),NOSPLIT,$0-16
#ifndef GOEXPERIMENT_regabiargs
MOVV ptr+0(FP), R4
MOVV n+8(FP), R5
#endif
ADDV R4, R5, R6
// if less than 8 bytes, do one byte at a time
SGTU $8, R5, R8
BNE R8, out
// do one byte at a time until 8-aligned
AND $7, R4, R8
BEQ R8, words
MOVB R0, (R4)
ADDV $1, R4
JMP -4(PC)
words:
// do 8 bytes at a time if there is room
ADDV $-7, R6, R5
PCALIGN $16
SGTU R5, R4, R8
BEQ R8, out
MOVV R0, (R4)
ADDV $8, R4
JMP -4(PC)
out:
BEQ R4, R6, done
MOVB R0, (R4)
ADDV $1, R4
JMP -3(PC)
done:
RET
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