/ error	= lock(flag)

.globl	_lock, cerror

_lock:
	mov	r5,-(sp)
	mov	sp,r5
	mov	4(r5),0f
	sys	0; 9f
	.data
9:
	sys	lock; 0:..
	.text
	bec	1f
	jmp	cerror
1:
	mov	(sp)+,r5
	rts	pc