ref: 2e6fb00af4fae7afd8d6bc9767b89ff0da5670dd
dir: /sys/src/libc/amd64/atomic64.s/
/* get variants */ TEXT agetv+0(SB),1,$0 MOVQ (RARG), AX RET /* set variants */ TEXT aswapv+0(SB),1,$0 MOVQ v+8(FP), AX LOCK; XCHGQ (RARG), AX RET /* inc variants */ TEXT aincv+0(SB),1,$0 MOVQ v+8(FP), BX MOVQ BX, AX LOCK; XADDQ AX, (RARG) ADDQ BX, AX RET /* cas variants */ TEXT acasv+0(SB),1,$0 MOVQ c+8(FP), AX MOVQ v+16(FP), BX LOCK; CMPXCHGQ BX, (RARG) SETEQ AX MOVBLZX AX, AX RET