Current Path : /usr/src/lib/libc/i386/string/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
Current File : //usr/src/lib/libc/i386/string/strcmp.S |
/* * Copyright (c) 1993 Winning Strategies, Inc. * 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Winning Strategies, Inc. * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. */ #include <machine/asm.h> __FBSDID("$FreeBSD: release/9.1.0/lib/libc/i386/string/strcmp.S 217106 2011-01-07 16:08:40Z kib $"); /* * strcmp(s1, s2) * return an integer greater than, equal to, or less than 0, * according as string s1 is greater than, equal to, or less * than the string s2. * * %eax - pointer to s1 * %edx - pointer to s2 * * Written by: * J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc. */ /* * I've unrolled the loop eight times: large enough to make a * significant difference, and small enough not to totally trash the * cache. */ ENTRY(strcmp) movl 0x04(%esp),%eax movl 0x08(%esp),%edx jmp L2 /* Jump into the loop! */ .align 2,0x90 L1: incl %eax incl %edx L2: movb (%eax),%cl testb %cl,%cl je L3 cmpb %cl,(%edx) jne L3 incl %eax incl %edx movb (%eax),%cl testb %cl,%cl je L3 cmpb %cl,(%edx) jne L3 incl %eax incl %edx movb (%eax),%cl testb %cl,%cl je L3 cmpb %cl,(%edx) jne L3 incl %eax incl %edx movb (%eax),%cl testb %cl,%cl je L3 cmpb %cl,(%edx) jne L3 incl %eax incl %edx movb (%eax),%cl testb %cl,%cl je L3 cmpb %cl,(%edx) jne L3 incl %eax incl %edx movb (%eax),%cl testb %cl,%cl je L3 cmpb %cl,(%edx) jne L3 incl %eax incl %edx movb (%eax),%cl testb %cl,%cl je L3 cmpb %cl,(%edx) jne L3 incl %eax incl %edx movb (%eax),%cl testb %cl,%cl je L3 cmpb %cl,(%edx) je L1 .align 2, 0x90 L3: movzbl (%eax),%eax /* unsigned comparison */ movzbl (%edx),%edx subl %edx,%eax ret END(strcmp) .section .note.GNU-stack,"",%progbits