strcmp.S revision 1.1 1 /* $NetBSD: strcmp.S,v 1.1 2005/12/20 19:28:50 christos Exp $ */
2
3 /*-
4 * Copyright (c) 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Ralph Campbell.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #include <mips/asm.h>
36
37 #if defined(LIBC_SCCS) && !defined(lint)
38 ASMSTR("from: @(#)strcmp.s 8.1 (Berkeley) 6/4/93")
39 ASMSTR("$NetBSD: strcmp.S,v 1.1 2005/12/20 19:28:50 christos Exp $")
40 #endif /* LIBC_SCCS and not lint */
41
42 #ifdef __ABICALLS__
43 .abicalls
44 #endif
45
46 /*
47 * NOTE: this version assumes unsigned chars in order to be "8 bit clean".
48 */
49 LEAF(strcmp)
50 1:
51 lbu t0, 0(a0) # get two bytes and compare them
52 lbu t1, 0(a1)
53 beq t0, zero, LessOrEq # end of first string?
54 bne t0, t1, NotEq
55 lbu t0, 1(a0) # unroll loop
56 lbu t1, 1(a1)
57 add a0, a0, 2
58 beq t0, zero, LessOrEq # end of first string?
59 add a1, a1, 2
60 beq t0, t1, 1b
61 NotEq:
62 subu v0, t0, t1
63 j ra
64 LessOrEq:
65 subu v0, zero, t1
66 j ra
67 END(strcmp)
68