git: 9front

ref: 1dfa2d264d2e316475f370032c5b0bb239ddd621
dir: /sys/src/libc/alpha/tas.s/

View raw version 
TEXT	_tas(SB), $-8
	MOVQ	R0, R1			/* l */
tas1:
	MOVLL	(R1), R0		/* l->key */
	BNE	R0, tas2
	MOVQ	$1, R2
	MOVLC	R2, (R1)		/* l->key = 1 */
	BEQ	R2, tas1		/* write failed, try again? */
tas2:
	RET