# gcc -nostdlib -nostdinc -Wl,--oformat,binary,-Ttext,0x100 a.s
# Test undocumented LOCK - if 0xf1 is a prefix, print 'y'
	.code16
	xor	%ax, %ax
	mov	%ax, %es
	mov	0, %ax
	cmp	%es:0, %ax
	jne	1f
	mov	$'!', %dl
ed:	mov	$2, %ah
	int	$0x21
	int	$0x20
1:	es
	lock
	cmp	0, %ax
	jne	1f
	mov	$'?', %dl
	jmp	ed
1:	es
	.byte	0xf1
	cmp	0, %ax
	mov	$'y', %dl
	jne	ed
	mov	$'n', %dl
	jmp	ed
