ref: 42074003ca31dea9589012fe3e235e4ddec5be1f
dir: /sys/src/libthread/xincamd64.s/
/*TEXT xadd(SB),$0 /* long xadd(long *, long); */ /* MOVL i+8(FP),AX /* LOCK /* XADDL AX, (RARG) /* RET */ TEXT _xinc(SB),$0 /* void _xinc(long *); */ LOCK; INCL 0(RARG) RET TEXT _xdec(SB),$0 /* long _xdec(long *); */ MOVL $0, AX MOVL $1, BX LOCK; DECL 0(RARG) CMOVLNE BX, AX RET