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// Copyright 2011 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.
// +build !race
#include "textflag.h"
TEXT ·SwapInt32(SB),NOSPLIT,$0-12
JMP ·SwapUint32(SB)
TEXT ·SwapUint32(SB),NOSPLIT,$0-12
MOVL addr+0(FP), BP
MOVL new+4(FP), AX
XCHGL AX, 0(BP)
MOVL AX, old+8(FP)
RET
TEXT ·SwapInt64(SB),NOSPLIT,$0-20
JMP ·SwapUint64(SB)
TEXT ·SwapUint64(SB),NOSPLIT,$0-20
// no XCHGQ so use CMPXCHG8B loop
MOVL addr+0(FP), BP
TESTL $7, BP
JZ 2(PC)
MOVL 0, AX // crash with nil ptr deref
// CX:BX = new
MOVL new_lo+4(FP), BX
MOVL new_hi+8(FP), CX
// DX:AX = *addr
MOVL 0(BP), AX
MOVL 4(BP), DX
swaploop:
// if *addr == DX:AX
// *addr = CX:BX
// else
// DX:AX = *addr
// all in one instruction
LOCK
CMPXCHG8B 0(BP)
JNZ swaploop
// success
// return DX:AX
MOVL AX, old_lo+12(FP)
MOVL DX, old_hi+16(FP)
RET
TEXT ·SwapUintptr(SB),NOSPLIT,$0-12
JMP ·SwapUint32(SB)
TEXT ·SwapPointer(SB),NOSPLIT,$0-12
JMP ·SwapUint32(SB)
TEXT ·CompareAndSwapInt32(SB),NOSPLIT,$0-13
JMP ·CompareAndSwapUint32(SB)
TEXT ·CompareAndSwapUint32(SB),NOSPLIT,$0-13
MOVL addr+0(FP), BP
MOVL old+4(FP), AX
MOVL new+8(FP), CX
// CMPXCHGL was introduced on the 486.
LOCK
CMPXCHGL CX, 0(BP)
SETEQ swapped+12(FP)
RET
TEXT ·CompareAndSwapUintptr(SB),NOSPLIT,$0-13
JMP ·CompareAndSwapUint32(SB)
TEXT ·CompareAndSwapPointer(SB),NOSPLIT,$0-13
JMP ·CompareAndSwapUint32(SB)
TEXT ·CompareAndSwapInt64(SB),NOSPLIT,$0-21
JMP ·CompareAndSwapUint64(SB)
TEXT ·CompareAndSwapUint64(SB),NOSPLIT,$0-21
MOVL addr+0(FP), BP
TESTL $7, BP
JZ 2(PC)
MOVL 0, AX // crash with nil ptr deref
MOVL old_lo+4(FP), AX
MOVL old_hi+8(FP), DX
MOVL new_lo+12(FP), BX
MOVL new_hi+16(FP), CX
// CMPXCHG8B was introduced on the Pentium.
LOCK
CMPXCHG8B 0(BP)
SETEQ swapped+20(FP)
RET
TEXT ·AddInt32(SB),NOSPLIT,$0-12
JMP ·AddUint32(SB)
TEXT ·AddUint32(SB),NOSPLIT,$0-12
MOVL addr+0(FP), BP
MOVL delta+4(FP), AX
MOVL AX, CX
// XADD was introduced on the 486.
LOCK
XADDL AX, 0(BP)
ADDL AX, CX
MOVL CX, new+8(FP)
RET
TEXT ·AddUintptr(SB),NOSPLIT,$0-12
JMP ·AddUint32(SB)
TEXT ·AddInt64(SB),NOSPLIT,$0-20
JMP ·AddUint64(SB)
TEXT ·AddUint64(SB),NOSPLIT,$0-20
// no XADDQ so use CMPXCHG8B loop
MOVL addr+0(FP), BP
TESTL $7, BP
JZ 2(PC)
MOVL 0, AX // crash with nil ptr deref
// DI:SI = delta
MOVL delta_lo+4(FP), SI
MOVL delta_hi+8(FP), DI
// DX:AX = *addr
MOVL 0(BP), AX
MOVL 4(BP), DX
addloop:
// CX:BX = DX:AX (*addr) + DI:SI (delta)
MOVL AX, BX
MOVL DX, CX
ADDL SI, BX
ADCL DI, CX
// if *addr == DX:AX {
// *addr = CX:BX
// } else {
// DX:AX = *addr
// }
// all in one instruction
LOCK
CMPXCHG8B 0(BP)
JNZ addloop
// success
// return CX:BX
MOVL BX, new_lo+12(FP)
MOVL CX, new_hi+16(FP)
RET
TEXT ·LoadInt32(SB),NOSPLIT,$0-8
JMP ·LoadUint32(SB)
TEXT ·LoadUint32(SB),NOSPLIT,$0-8
MOVL addr+0(FP), AX
MOVL 0(AX), AX
MOVL AX, val+4(FP)
RET
TEXT ·LoadInt64(SB),NOSPLIT,$0-12
JMP ·LoadUint64(SB)
TEXT ·LoadUint64(SB),NOSPLIT,$0-12
MOVL addr+0(FP), AX
TESTL $7, AX
JZ 2(PC)
MOVL 0, AX // crash with nil ptr deref
// MOVQ and EMMS were introduced on the Pentium MMX.
// MOVQ (%EAX), %MM0
BYTE $0x0f; BYTE $0x6f; BYTE $0x00
// MOVQ %MM0, 0x8(%ESP)
BYTE $0x0f; BYTE $0x7f; BYTE $0x44; BYTE $0x24; BYTE $0x08
EMMS
RET
TEXT ·LoadUintptr(SB),NOSPLIT,$0-8
JMP ·LoadUint32(SB)
TEXT ·LoadPointer(SB),NOSPLIT,$0-8
JMP ·LoadUint32(SB)
TEXT ·StoreInt32(SB),NOSPLIT,$0-8
JMP ·StoreUint32(SB)
TEXT ·StoreUint32(SB),NOSPLIT,$0-8
MOVL addr+0(FP), BP
MOVL val+4(FP), AX
XCHGL AX, 0(BP)
RET
TEXT ·StoreInt64(SB),NOSPLIT,$0-12
JMP ·StoreUint64(SB)
TEXT ·StoreUint64(SB),NOSPLIT,$0-12
MOVL addr+0(FP), AX
TESTL $7, AX
JZ 2(PC)
MOVL 0, AX // crash with nil ptr deref
// MOVQ and EMMS were introduced on the Pentium MMX.
// MOVQ 0x8(%ESP), %MM0
BYTE $0x0f; BYTE $0x6f; BYTE $0x44; BYTE $0x24; BYTE $0x08
// MOVQ %MM0, (%EAX)
BYTE $0x0f; BYTE $0x7f; BYTE $0x00
EMMS
// This is essentially a no-op, but it provides required memory fencing.
// It can be replaced with MFENCE, but MFENCE was introduced only on the Pentium4 (SSE2).
XORL AX, AX
LOCK
XADDL AX, (SP)
RET
TEXT ·StoreUintptr(SB),NOSPLIT,$0-8
JMP ·StoreUint32(SB)
TEXT ·StorePointer(SB),NOSPLIT,$0-8
JMP ·StoreUint32(SB)
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