strncmp.S revision 1.5 
1/*	$NetBSD: strncmp.S,v 1.5 2013/07/18 22:42:50 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 1.5 2013/07/18 22:42:50 matt Exp $")
37#endif /* LIBC_SCCS and not lint */
38
39
40#ifdef __mcoldfire__
41#define GETC(a,b)	mvsb	a,b
42#define	SUBC(a,b)	mvsb	a,%d2; subl %d2,b
43#else
44#define GETC(a,b)	movb	a,b
45#define	SUBC(a,b)	subb	a,b
46#endif
47
48ENTRY(strncmp)
49	movl	12(%sp),%d0
50	jeq	L4
51	movl	4(%sp),%a0
52	movl	8(%sp),%a1
53	movl	%d2,-(%sp)	| save temp
54L1:				/* unroll by 4 for m680[23]0's */
55	GETC((%a0)+,%d1)
56	jeq	L2
57	SUBC((%a1)+,%d1)
58	jne	L3
59	subql	#1,%d0
60	jeq	L4
61
62	GETC((%a0)+,%d1)
63	jeq	L2
64	SUBC((%a1)+,%d1)
65	jne	L3
66	subql	#1,%d0
67	jeq	L4
68
69	GETC((%a0)+,%d1)
70	jeq	L2
71	SUBC((%a1)+,%d1)
72	jne	L3
73	subql	#1,%d0
74	jeq	L4
75
76	GETC((%a0)+,%d1)
77	jeq	L2
78	SUBC((%a1)+,%d1)
79	jne	L3
80	subql	#1,%d0
81	jne	L1
82#ifdef __mcoldfire__
83	movl	(%sp)+,%d2		| restore temp
84#endif
85L4:	rts
86
87L2:	SUBC((%a1),%d1)
88L3:
89#ifdef __mcoldfire__
90	movl	(%sp)+,%d2		| restore temp
91#else
92	EXTBL(%d1)
93#endif
94	movl	%d1,%d0
95	rts
96END(strncmp)
97