[dev.power64] sync/atomic: implement for asm_power64x.s

LGTM=rsc
R=rsc, iant
CC=golang-codereviews
https://golang.org/cl/124220043

src/pkg/sync/atomic/asm_power64x.s

+// Copyright 2014 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 power64 power64le
+
+#include "../../../cmd/ld/textflag.h"
+
+TEXT ·SwapInt32(SB),NOSPLIT,$0-20
+	BR	·SwapUint32(SB)
+
+TEXT ·SwapUint32(SB),NOSPLIT,$0-20
+	MOVD	addr+0(FP), R3
+	MOVW	new+8(FP), R4
+	SYNC
+	LWAR	(R3), R5
+	STWCCC	R4, (R3)
+	BNE	-3(PC)
+	SYNC
+	ISYNC
+	MOVW	R5, old+16(FP)
+	RETURN
+
+TEXT ·SwapInt64(SB),NOSPLIT,$0-24
+	BR	·SwapUint64(SB)
+
+TEXT ·SwapUint64(SB),NOSPLIT,$0-24
+	MOVD	addr+0(FP), R3
+	MOVD	new+8(FP), R4
+	SYNC
+	LDAR	(R3), R5
+	STDCCC	R4, (R3)
+	BNE	-3(PC)
+	SYNC
+	ISYNC
+	MOVD	R5, old+16(FP)
+	RETURN
+
+TEXT ·SwapUintptr(SB),NOSPLIT,$0-24
+	BR	·SwapUint64(SB)
+
+TEXT ·SwapPointer(SB),NOSPLIT,$0-24
+	BR	·SwapUint64(SB)
+
+TEXT ·CompareAndSwapInt32(SB),NOSPLIT,$0-17
+	BR	·CompareAndSwapUint32(SB)
+
+TEXT ·CompareAndSwapUint32(SB),NOSPLIT,$0-17
+	MOVD	addr+0(FP), R3
+	MOVW	old+8(FP), R4
+	MOVW	new+12(FP), R5
+	SYNC
+	LWAR	(R3), R6
+	CMPW	R6, R4
+	BNE	8(PC)
+	STWCCC	R5, (R3)
+	BNE	-5(PC)
+	SYNC
+	ISYNC
+	MOVD	$1, R3
+	MOVB	R3, swapped+16(FP)
+	RETURN
+	MOVB	R0, swapped+16(FP)
+	RETURN
+
+TEXT ·CompareAndSwapUintptr(SB),NOSPLIT,$0-25
+	BR	·CompareAndSwapUint64(SB)
+
+TEXT ·CompareAndSwapPointer(SB),NOSPLIT,$0-25
+	BR	·CompareAndSwapUint64(SB)
+
+TEXT ·CompareAndSwapInt64(SB),NOSPLIT,$0-25
+	BR	·CompareAndSwapUint64(SB)
+
+TEXT ·CompareAndSwapUint64(SB),NOSPLIT,$0-25
+	MOVD	addr+0(FP), R3
+	MOVD	old+8(FP), R4
+	MOVD	new+16(FP), R5
+	SYNC
+	LDAR	(R3), R6
+	CMP	R6, R4
+	BNE	8(PC)
+	STDCCC	R5, (R3)
+	BNE	-5(PC)
+	SYNC
+	ISYNC
+	MOVD	$1, R3
+	MOVB	R3, swapped+24(FP)
+	RETURN
+	MOVB	R0, swapped+24(FP)
+	RETURN
+
+TEXT ·AddInt32(SB),NOSPLIT,$0-20
+	BR	·AddUint32(SB)
+
+TEXT ·AddUint32(SB),NOSPLIT,$0-20
+	MOVD	addr+0(FP), R3
+	MOVW	delta+8(FP), R4
+	SYNC
+	LWAR	(R3), R5
+	ADD	R4, R5
+	STWCCC	R5, (R3)
+	BNE	-4(PC)
+	SYNC
+	ISYNC
+	MOVW	R5, ret+16(FP)
+	RETURN
+
+TEXT ·AddUintptr(SB),NOSPLIT,$0-24
+	BR	·AddUint64(SB)
+
+TEXT ·AddInt64(SB),NOSPLIT,$0-24
+	BR	·AddUint64(SB)
+
+TEXT ·AddUint64(SB),NOSPLIT,$0-24
+	MOVD	addr+0(FP), R3
+	MOVD	delta+8(FP), R4
+	SYNC
+	LDAR	(R3), R5
+	ADD	R4, R5
+	STDCCC	R5, (R3)
+	BNE	-4(PC)
+	SYNC
+	ISYNC
+	MOVD	R5, ret+16(FP)
+	RETURN
+
+TEXT ·LoadInt32(SB),NOSPLIT,$0-12
+	BR	·LoadUint32(SB)
+
+TEXT ·LoadUint32(SB),NOSPLIT,$0-12
+	MOVD	addr+0(FP), R3
+	SYNC
+	MOVW	0(R3), R3
+	CMPW	R3, R3, CR7
+	BC	4, 30, 1(PC)	// bne- cr7,0x4
+	ISYNC
+	MOVW	R3, val+8(FP)
+	RETURN
+
+TEXT ·LoadInt64(SB),NOSPLIT,$0-16
+	BR	·LoadUint64(SB)
+
+TEXT ·LoadUint64(SB),NOSPLIT,$0-16
+	MOVD	addr+0(FP), R3
+	SYNC
+	MOVD	0(R3), R3
+	CMP	R3, R3, CR7
+	BC	4, 30, 1(PC)	// bne- cr7,0x4
+	ISYNC
+	MOVD	R3, val+8(FP)
+	RETURN
+
+TEXT ·LoadUintptr(SB),NOSPLIT,$0-16
+	BR	·LoadPointer(SB)
+
+TEXT ·LoadPointer(SB),NOSPLIT,$0-16
+	BR	·LoadUint64(SB)
+
+TEXT ·StoreInt32(SB),NOSPLIT,$0-12
+	BR	·StoreUint32(SB)
+
+TEXT ·StoreUint32(SB),NOSPLIT,$0-12
+	MOVD	addr+0(FP), R3
+	MOVW	val+8(FP), R4
+	SYNC
+	MOVW	R4, 0(R3)
+	RETURN
+
+TEXT ·StoreInt64(SB),NOSPLIT,$0-16
+	BR	·StoreUint64(SB)
+
+TEXT ·StoreUint64(SB),NOSPLIT,$0-16
+	MOVD	addr+0(FP), R3
+	MOVD	val+8(FP), R4
+	SYNC
+	MOVD	R4, 0(R3)
+	RETURN
+
+TEXT ·StoreUintptr(SB),NOSPLIT,$0-16
+	BR	·StorePointer(SB)
+
+TEXT ·StorePointer(SB),NOSPLIT,$0-16
+	BR	·StoreUint64(SB)