xref: /freebsd/lib/libc/i386/string/bcmp.S (revision 8f76bb7dad48538c6832c2fb466a433d2a3f8cd5)
1/*
2 * Copyright (c) 1993 Winning Strategies, Inc.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *      This product includes software developed by Winning Strategies, Inc.
16 * 4. The name of the author may not be used to endorse or promote products
17 *    derived from this software without specific prior written permission
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include <machine/asm.h>
32/*
33 * bcmp (void *b1, void *b2, size_t len)
34 *
35 * Written by:
36 *	J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc.
37 */
38
39ENTRY(bcmp)
40	pushl	%edi
41	pushl	%esi
42	movl	12(%esp),%edi
43	movl	16(%esp),%esi
44	cld				/* set compare direction forward */
45
46	movl	20(%esp),%ecx		/* compare by words */
47	shrl	$2,%ecx
48	repe
49	cmpsl
50	jne	L1
51
52	movl	20(%esp),%ecx		/* compare remainder by bytes */
53	andl	$3,%ecx
54	repe
55	cmpsb
56L1:
57	setne	%al
58	movsbl	%al,%eax
59	popl	%esi
60	popl	%edi
61	ret
62END(bcmp)
63
64	.section .note.GNU-stack,"",%progbits
65