12ceb2ce9SGarrett Wollman/* 22ceb2ce9SGarrett Wollman * Copyright (c) 1993 Winning Strategies, Inc. 32ceb2ce9SGarrett Wollman * All rights reserved. 42ceb2ce9SGarrett Wollman * 52ceb2ce9SGarrett Wollman * Redistribution and use in source and binary forms, with or without 62ceb2ce9SGarrett Wollman * modification, are permitted provided that the following conditions 72ceb2ce9SGarrett Wollman * are met: 82ceb2ce9SGarrett Wollman * 1. Redistributions of source code must retain the above copyright 92ceb2ce9SGarrett Wollman * notice, this list of conditions and the following disclaimer. 102ceb2ce9SGarrett Wollman * 2. Redistributions in binary form must reproduce the above copyright 112ceb2ce9SGarrett Wollman * notice, this list of conditions and the following disclaimer in the 122ceb2ce9SGarrett Wollman * documentation and/or other materials provided with the distribution. 132ceb2ce9SGarrett Wollman * 3. All advertising materials mentioning features or use of this software 142ceb2ce9SGarrett Wollman * must display the following acknowledgement: 152ceb2ce9SGarrett Wollman * This product includes software developed by Winning Strategies, Inc. 162ceb2ce9SGarrett Wollman * 4. The name of the author may not be used to endorse or promote products 172ceb2ce9SGarrett Wollman * derived from this software without specific prior written permission 182ceb2ce9SGarrett Wollman * 192ceb2ce9SGarrett Wollman * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 202ceb2ce9SGarrett Wollman * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 212ceb2ce9SGarrett Wollman * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 222ceb2ce9SGarrett Wollman * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 232ceb2ce9SGarrett Wollman * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 242ceb2ce9SGarrett Wollman * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 252ceb2ce9SGarrett Wollman * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 262ceb2ce9SGarrett Wollman * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 272ceb2ce9SGarrett Wollman * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 282ceb2ce9SGarrett Wollman * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 292ceb2ce9SGarrett Wollman */ 302ceb2ce9SGarrett Wollman 312ceb2ce9SGarrett Wollman#if defined(LIBC_RCS) && !defined(lint) 32717d9cddSDavid Greenman .text 337f3dea24SPeter Wemm .asciz "$FreeBSD$" 342ceb2ce9SGarrett Wollman#endif /* LIBC_RCS and not lint */ 352ceb2ce9SGarrett Wollman 36e6d808aeSPeter Wemm#include <machine/asm.h> 372ceb2ce9SGarrett Wollman 382ceb2ce9SGarrett Wollman/* 392ceb2ce9SGarrett Wollman * memcmp (void *b1, void *b2, size_t len) 402ceb2ce9SGarrett Wollman * 412ceb2ce9SGarrett Wollman * Written by: 422ceb2ce9SGarrett Wollman * J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc. 432ceb2ce9SGarrett Wollman */ 442ceb2ce9SGarrett Wollman 452ceb2ce9SGarrett WollmanENTRY(memcmp) 462ceb2ce9SGarrett Wollman pushl %edi 472ceb2ce9SGarrett Wollman pushl %esi 482ceb2ce9SGarrett Wollman movl 12(%esp),%edi 492ceb2ce9SGarrett Wollman movl 16(%esp),%esi 502ceb2ce9SGarrett Wollman cld /* set compare direction forward */ 512ceb2ce9SGarrett Wollman 522ceb2ce9SGarrett Wollman movl 20(%esp),%ecx /* compare by words */ 532ceb2ce9SGarrett Wollman shrl $2,%ecx 542ceb2ce9SGarrett Wollman repe 552ceb2ce9SGarrett Wollman cmpsl 562ceb2ce9SGarrett Wollman jne L5 /* do we match so far? */ 572ceb2ce9SGarrett Wollman 582ceb2ce9SGarrett Wollman movl 20(%esp),%ecx /* compare remainder by bytes */ 592ceb2ce9SGarrett Wollman andl $3,%ecx 602ceb2ce9SGarrett Wollman repe 612ceb2ce9SGarrett Wollman cmpsb 622ceb2ce9SGarrett Wollman jne L6 /* do we match? */ 632ceb2ce9SGarrett Wollman 642ceb2ce9SGarrett Wollman xorl %eax,%eax /* we match, return zero */ 652ceb2ce9SGarrett Wollman popl %esi 662ceb2ce9SGarrett Wollman popl %edi 672ceb2ce9SGarrett Wollman ret 682ceb2ce9SGarrett Wollman 692ceb2ce9SGarrett WollmanL5: movl $4,%ecx /* We know that one of the next */ 702ceb2ce9SGarrett Wollman subl %ecx,%edi /* four pairs of bytes do not */ 712ceb2ce9SGarrett Wollman subl %ecx,%esi /* match. */ 722ceb2ce9SGarrett Wollman repe 732ceb2ce9SGarrett Wollman cmpsb 742ceb2ce9SGarrett WollmanL6: movzbl -1(%edi),%eax /* Perform unsigned comparison */ 752ceb2ce9SGarrett Wollman movzbl -1(%esi),%edx 762ceb2ce9SGarrett Wollman subl %edx,%eax 772ceb2ce9SGarrett Wollman popl %esi 782ceb2ce9SGarrett Wollman popl %edi 792ceb2ce9SGarrett Wollman ret 80