github.com/mattn/go@v0.0.0-20171011075504-07f7db3ea99f/src/runtime/internal/atomic/asm_arm64.s (about)

     1  // Copyright 2015 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  #include "textflag.h"
     6  
     7  // bool Cas(uint32 *ptr, uint32 old, uint32 new)
     8  // Atomically:
     9  //	if(*val == old){
    10  //		*val = new;
    11  //		return 1;
    12  //	} else
    13  //		return 0;
    14  TEXT runtime∕internal∕atomic·Cas(SB), NOSPLIT, $0-17
    15  	MOVD	ptr+0(FP), R0
    16  	MOVW	old+8(FP), R1
    17  	MOVW	new+12(FP), R2
    18  again:
    19  	LDAXRW	(R0), R3
    20  	CMPW	R1, R3
    21  	BNE	ok
    22  	STLXRW	R2, (R0), R3
    23  	CBNZ	R3, again
    24  ok:
    25  	CSET	EQ, R0
    26  	MOVB	R0, ret+16(FP)
    27  	RET
    28  
    29  TEXT runtime∕internal∕atomic·Casuintptr(SB), NOSPLIT, $0-25
    30  	B	runtime∕internal∕atomic·Cas64(SB)
    31  
    32  TEXT runtime∕internal∕atomic·Loaduintptr(SB), NOSPLIT, $-8-16
    33  	B	runtime∕internal∕atomic·Load64(SB)
    34  
    35  TEXT runtime∕internal∕atomic·Loaduint(SB), NOSPLIT, $-8-16
    36  	B	runtime∕internal∕atomic·Load64(SB)
    37  
    38  TEXT runtime∕internal∕atomic·Storeuintptr(SB), NOSPLIT, $0-16
    39  	B	runtime∕internal∕atomic·Store64(SB)
    40  
    41  TEXT runtime∕internal∕atomic·Xadduintptr(SB), NOSPLIT, $0-24
    42  	B	runtime∕internal∕atomic·Xadd64(SB)
    43  
    44  TEXT runtime∕internal∕atomic·Loadint64(SB), NOSPLIT, $0-16
    45  	B	runtime∕internal∕atomic·Load64(SB)
    46  
    47  TEXT runtime∕internal∕atomic·Xaddint64(SB), NOSPLIT, $0-24
    48  	B	runtime∕internal∕atomic·Xadd64(SB)
    49  
    50  // bool Casp1(void **val, void *old, void *new)
    51  // Atomically:
    52  //	if(*val == old){
    53  //		*val = new;
    54  //		return 1;
    55  //	} else
    56  //		return 0;
    57  TEXT runtime∕internal∕atomic·Casp1(SB), NOSPLIT, $0-25
    58  	B runtime∕internal∕atomic·Cas64(SB)