diff options
Diffstat (limited to 'src/runtime/internal/atomic/sys_nonlinux_arm.s')
-rw-r--r-- | src/runtime/internal/atomic/sys_nonlinux_arm.s | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/src/runtime/internal/atomic/sys_nonlinux_arm.s b/src/runtime/internal/atomic/sys_nonlinux_arm.s new file mode 100644 index 0000000..b55bf90 --- /dev/null +++ b/src/runtime/internal/atomic/sys_nonlinux_arm.s @@ -0,0 +1,79 @@ +// 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 + +#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 + |