blob: 04036ca9702da4ce1d25cb16a8f4dcdb64be398c [file] [log] [blame]
// Copyright 2015 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.
//go:build !linux
// +build !linux
#include "textflag.h"
// TODO(minux): this is only valid for ARMv6+
// bool armcas(int32 *val, int32 old, int32 new)
// Atomically:
// if(*val == old){
// *val = new;
// return 1;
// }else
// return 0;
TEXT ·Cas(SB),NOSPLIT,$0
JMP ·armcas(SB)
// Non-linux OSes support only single processor machines before ARMv7.
// So we don't need memory barriers if goarm < 7. And we fail loud at
// startup (runtime.checkgoarm) if it is a multi-processor but goarm < 7.
TEXT ·Load(SB),NOSPLIT|NOFRAME,$0-8
MOVW addr+0(FP), R0
MOVW (R0), R1
MOVB runtime·goarm(SB), R11
CMP $7, R11
BLT 2(PC)
DMB MB_ISH
MOVW R1, ret+4(FP)
RET
TEXT ·Store(SB),NOSPLIT,$0-8
MOVW addr+0(FP), R1
MOVW v+4(FP), R2
MOVB runtime·goarm(SB), R8
CMP $7, R8
BLT 2(PC)
DMB MB_ISH
MOVW R2, (R1)
CMP $7, R8
BLT 2(PC)
DMB MB_ISH
RET
TEXT ·Load8(SB),NOSPLIT|NOFRAME,$0-5
MOVW addr+0(FP), R0
MOVB (R0), R1
MOVB runtime·goarm(SB), R11
CMP $7, R11
BLT 2(PC)
DMB MB_ISH
MOVB R1, ret+4(FP)
RET
TEXT ·Store8(SB),NOSPLIT,$0-5
MOVW addr+0(FP), R1
MOVB v+4(FP), R2
MOVB runtime·goarm(SB), R8
CMP $7, R8
BLT 2(PC)
DMB MB_ISH
MOVB R2, (R1)
CMP $7, R8
BLT 2(PC)
DMB MB_ISH
RET