minix/lib/libc/arch/vax/string/index.S

65 lines
2.1 KiB
ArmAsm
Raw Normal View History

/* $NetBSD: index.S,v 1.4 2011/01/25 02:38:15 matt Exp $ */
/*
* Copyright (c) 1980, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Find the first occurence of c in the string cp.
* Return pointer to match or null pointer.
*
* char *
* index(cp, c)
* char *cp, c;
*/
#include "DEFS.h"
#ifdef LIBC_SCCS
RCSID("$NetSBD$")
#endif
/* Alas not quite twice as fast as the generic C version on a uvax2 */
ENTRY(index, 0)
movq 4(%ap),%r0 # %r0 = cp; %r1 = c
tstb %r1 # special case, looking for '\0'
jeql 3f
1:
cmpb (%r0),%r1
jeql 2f
tstb (%r0)+
jneq 1b
clrl %r0 # return NULL if no match
2:
ret
3:
tstb (%r0)+
jneq 3b
decl %r0
jbr 2b
END(index)