strncmp.S revision 1.3 
1/*	$NetBSD: strncmp.S,v 1.3 2013/07/16 20:49:42 matt Exp $	*/
2
3/*-
4 * Copyright (c) 1997 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Hiroshi Horimoto <horimoto@cs-aoi.cs.sist.ac.jp> and
9 * by J.T. Conklin <jtc@NetBSD.org>.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32
33#include <machine/asm.h>
34
35#if defined(LIBC_SCCS) && !defined(lint)
36	RCSID("$NetBSD: strncmp.S,v 1.3 2013/07/16 20:49:42 matt Exp $")
37#endif /* LIBC_SCCS and not lint */
38
39ENTRY(strncmp)
40	movl	12(%sp),%d0
41	jeq	L4
42	movl	4(%sp),%a0
43	movl	8(%sp),%a1
44L1:				/* unroll by 4 for m680[23]0's */
45	movb	(%a0)+,%d1
46	jeq	L2
47	subb	(%a1)+,%d1
48	jne	L3
49	subql	#1,%d0
50	jeq	L4
51
52	movb	(%a0)+,%d1
53	jeq	L2
54	subb	(%a1)+,%d1
55	jne	L3
56	subql	#1,%d0
57	jeq	L4
58
59	movb	(%a0)+,%d1
60	jeq	L2
61	subb	(%a1)+,%d1
62	jne	L3
63	subql	#1,%d0
64	jeq	L4
65
66	movb	(%a0)+,%d1
67	jeq	L2
68	subb	(%a1)+,%d1
69	jne	L3
70	subql	#1,%d0
71	jne	L1
72L4:	rts
73
74L2:	subb	(%a1),%d1
75L3:	scs	%d0
76	EXTBL(%d0)
77	movb	%d1,%d0
78	rts
79