xref: /illumos-gate/usr/src/lib/libc/i386/gen/lock.S (revision 5d9d9091f564c198a760790b0bfa72c44e17912b)
1*5d9d9091SRichard Lowe/*
2*5d9d9091SRichard Lowe * CDDL HEADER START
3*5d9d9091SRichard Lowe *
4*5d9d9091SRichard Lowe * The contents of this file are subject to the terms of the
5*5d9d9091SRichard Lowe * Common Development and Distribution License (the "License").
6*5d9d9091SRichard Lowe * You may not use this file except in compliance with the License.
7*5d9d9091SRichard Lowe *
8*5d9d9091SRichard Lowe * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9*5d9d9091SRichard Lowe * or http://www.opensolaris.org/os/licensing.
10*5d9d9091SRichard Lowe * See the License for the specific language governing permissions
11*5d9d9091SRichard Lowe * and limitations under the License.
12*5d9d9091SRichard Lowe *
13*5d9d9091SRichard Lowe * When distributing Covered Code, include this CDDL HEADER in each
14*5d9d9091SRichard Lowe * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15*5d9d9091SRichard Lowe * If applicable, add the following below this CDDL HEADER, with the
16*5d9d9091SRichard Lowe * fields enclosed by brackets "[]" replaced with your own identifying
17*5d9d9091SRichard Lowe * information: Portions Copyright [yyyy] [name of copyright owner]
18*5d9d9091SRichard Lowe *
19*5d9d9091SRichard Lowe * CDDL HEADER END
20*5d9d9091SRichard Lowe */
21*5d9d9091SRichard Lowe/*
22*5d9d9091SRichard Lowe * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
23*5d9d9091SRichard Lowe * Use is subject to license terms.
24*5d9d9091SRichard Lowe */
25*5d9d9091SRichard Lowe
26*5d9d9091SRichard Lowe	.file	"lock.s"
27*5d9d9091SRichard Lowe
28*5d9d9091SRichard Lowe#include "SYS.h"
29*5d9d9091SRichard Lowe
30*5d9d9091SRichard Lowe/
31*5d9d9091SRichard Lowe/ _lock_try(lp)
32*5d9d9091SRichard Lowe/	- returns non-zero on success.
33*5d9d9091SRichard Lowe/
34*5d9d9091SRichard Lowe	ENTRY(_lock_try)
35*5d9d9091SRichard Lowe	movl	$1,%eax
36*5d9d9091SRichard Lowe	movl	4(%esp),%ecx
37*5d9d9091SRichard Lowe	xchgb	%al, (%ecx)
38*5d9d9091SRichard Lowe	xorb	$1, %al
39*5d9d9091SRichard Lowe	ret
40*5d9d9091SRichard Lowe	SET_SIZE(_lock_try)
41*5d9d9091SRichard Lowe
42*5d9d9091SRichard Lowe/
43*5d9d9091SRichard Lowe/ _lock_clear(lp)
44*5d9d9091SRichard Lowe/	- clear lock and force it to appear unlocked in memory.
45*5d9d9091SRichard Lowe/
46*5d9d9091SRichard Lowe	ENTRY(_lock_clear)
47*5d9d9091SRichard Lowe	movl	4(%esp),%eax
48*5d9d9091SRichard Lowe	movb	$0, (%eax)
49*5d9d9091SRichard Lowe	ret
50*5d9d9091SRichard Lowe	SET_SIZE(_lock_clear)
51*5d9d9091SRichard Lowe
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