xref: /minix3/common/lib/libc/arch/mips/string/strcmp.S (revision b6cbf7203b080219de306404f8022a65b7884f33)
1*b6cbf720SGianluca Guida/*	$NetBSD: strcmp.S,v 1.2 2009/12/14 00:39:00 matt Exp $	*/
2*b6cbf720SGianluca Guida
3*b6cbf720SGianluca Guida/*-
4*b6cbf720SGianluca Guida * Copyright (c) 1991, 1993
5*b6cbf720SGianluca Guida *	The Regents of the University of California.  All rights reserved.
6*b6cbf720SGianluca Guida *
7*b6cbf720SGianluca Guida * This code is derived from software contributed to Berkeley by
8*b6cbf720SGianluca Guida * Ralph Campbell.
9*b6cbf720SGianluca Guida *
10*b6cbf720SGianluca Guida * Redistribution and use in source and binary forms, with or without
11*b6cbf720SGianluca Guida * modification, are permitted provided that the following conditions
12*b6cbf720SGianluca Guida * are met:
13*b6cbf720SGianluca Guida * 1. Redistributions of source code must retain the above copyright
14*b6cbf720SGianluca Guida *    notice, this list of conditions and the following disclaimer.
15*b6cbf720SGianluca Guida * 2. Redistributions in binary form must reproduce the above copyright
16*b6cbf720SGianluca Guida *    notice, this list of conditions and the following disclaimer in the
17*b6cbf720SGianluca Guida *    documentation and/or other materials provided with the distribution.
18*b6cbf720SGianluca Guida * 3. Neither the name of the University nor the names of its contributors
19*b6cbf720SGianluca Guida *    may be used to endorse or promote products derived from this software
20*b6cbf720SGianluca Guida *    without specific prior written permission.
21*b6cbf720SGianluca Guida *
22*b6cbf720SGianluca Guida * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23*b6cbf720SGianluca Guida * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24*b6cbf720SGianluca Guida * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25*b6cbf720SGianluca Guida * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26*b6cbf720SGianluca Guida * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27*b6cbf720SGianluca Guida * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28*b6cbf720SGianluca Guida * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29*b6cbf720SGianluca Guida * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30*b6cbf720SGianluca Guida * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31*b6cbf720SGianluca Guida * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32*b6cbf720SGianluca Guida * SUCH DAMAGE.
33*b6cbf720SGianluca Guida */
34*b6cbf720SGianluca Guida
35*b6cbf720SGianluca Guida#include <mips/asm.h>
36*b6cbf720SGianluca Guida
37*b6cbf720SGianluca Guida#if defined(LIBC_SCCS) && !defined(lint)
38*b6cbf720SGianluca Guida	/* RCSID("from: @(#)strcmp.s	8.1 (Berkeley) 6/4/93") */
39*b6cbf720SGianluca Guida	RCSID("$NetBSD: strcmp.S,v 1.2 2009/12/14 00:39:00 matt Exp $")
40*b6cbf720SGianluca Guida#endif /* LIBC_SCCS and not lint */
41*b6cbf720SGianluca Guida
42*b6cbf720SGianluca Guida/*
43*b6cbf720SGianluca Guida * NOTE: this version assumes unsigned chars in order to be "8 bit clean".
44*b6cbf720SGianluca Guida */
45*b6cbf720SGianluca GuidaLEAF(strcmp)
46*b6cbf720SGianluca Guida1:
47*b6cbf720SGianluca Guida	lbu	t0, 0(a0)		# get two bytes and compare them
48*b6cbf720SGianluca Guida	lbu	t1, 0(a1)
49*b6cbf720SGianluca Guida	beq	t0, zero, LessOrEq	# end of first string?
50*b6cbf720SGianluca Guida	bne	t0, t1, NotEq
51*b6cbf720SGianluca Guida	lbu	t0, 1(a0)		# unroll loop
52*b6cbf720SGianluca Guida	lbu	t1, 1(a1)
53*b6cbf720SGianluca Guida	PTR_ADD	a0, a0, 2
54*b6cbf720SGianluca Guida	beq	t0, zero, LessOrEq	# end of first string?
55*b6cbf720SGianluca Guida	PTR_ADD	a1, a1, 2
56*b6cbf720SGianluca Guida	beq	t0, t1, 1b
57*b6cbf720SGianluca GuidaNotEq:
58*b6cbf720SGianluca Guida	subu	v0, t0, t1
59*b6cbf720SGianluca Guida	j	ra
60*b6cbf720SGianluca GuidaLessOrEq:
61*b6cbf720SGianluca Guida	subu	v0, zero, t1
62*b6cbf720SGianluca Guida	j	ra
63*b6cbf720SGianluca GuidaEND(strcmp)
64