strchr.s revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
.ident "%Z%%M% %I% %E% SMI"
.file "%M%"
#include "SYS.h"
ENTRY(strchr) /* (char *, char) */
.loop:
movb (%rdi),%dl / %dl = byte of string
cmpb %sil,%dl / find it?
je .found / yes
testb %dl,%dl / is it null?
je .notfound
movb 1(%rdi),%dl / %dl = byte of string
cmpb %sil,%dl / find it?
je .found1 / yes
testb %dl,%dl / is it null?
je .notfound
movb 2(%rdi),%dl / %dl = byte of string
cmpb %sil,%dl / find it?
je .found2 / yes
testb %dl,%dl / is it null?
je .notfound
movb 3(%rdi),%dl / %dl = byte of string
cmpb %sil,%dl / find it?
je .found3 / yes
addq $4,%rdi
testb %dl,%dl / is it null?
jne .loop
.notfound:
xorl %eax,%eax / %rax = NULL
ret
.found3:
incq %rdi
.found2:
incq %rdi
.found1:
incq %rdi
.found:
movq %rdi,%rax
ret
SET_SIZE(strchr)