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view usr/src/lib/libc/i386/gen/memccpy.s @ 7298:b69e27387f74
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4758439 some files use "current date" sccs keywords
6560843 asm sources should not rely on .file "%M%" for naming STT_FILE symbols
6560958 Solaris:: perl modules should not use SCCS keywords in version information
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author | Mark J. Nelson <Mark.J.Nelson@Sun.COM> |
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date | Wed, 06 Aug 2008 16:29:39 -0600 |
parents | 68f95e015346 |
children |
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/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (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. */ .file "memccpy.s" #include <sys/asm_linkage.h> ANSI_PRAGMA_WEAK(memccpy,function) #include "SYS.h" ENTRY(memccpy) pushl %esi / save register variable movl 8(%esp),%eax / %eax = address of dest string movl 12(%esp),%esi / %esi = address of source string movb 16(%esp),%dh / %dh = character to search for movl 20(%esp),%ecx / %ecx = length to go still .loop: decl %ecx / decrement bytes to go jl .notfound movb (%esi),%dl movb %dl,(%eax) / move byte cmpb %dh,%dl / is it the byte sought? je .found / yes decl %ecx / decrement bytes to go jl .notfound movb 1(%esi),%dl movb %dl,1(%eax) / move byte cmpb %dh,%dl / is it the byte sought? je .found1 / yes decl %ecx / decrement bytes to go jl .notfound movb 2(%esi),%dl movb %dl,2(%eax) / move byte cmpb %dh,%dl / is it the byte sought? je .found2 / yes decl %ecx / decrement bytes to go jl .notfound movb 3(%esi),%dl movb %dl,3(%eax) / move byte addl $4,%esi addl $4,%eax cmpb %dh,%dl / is it the byte sought? jne .loop / no decl %eax .found: popl %esi / restore register variable incl %eax / return pointer to next byte in dest ret .align 4 .found2: incl %eax .found1: popl %esi / restore register variable addl $2,%eax / return pointer to next byte in dest ret .align 4 .notfound: popl %esi / restore register variable xorl %eax,%eax / search fails ret SET_SIZE(memccpy)