1/* 2 * Copyright (c) 1993 Winning Strategies, Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by Winning Strategies, Inc. 16 * 4. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31#include <machine/asm.h> 32/* 33 * strcmp(s1, s2) 34 * return an integer greater than, equal to, or less than 0, 35 * according as string s1 is greater than, equal to, or less 36 * than the string s2. 37 * 38 * %eax - pointer to s1 39 * %edx - pointer to s2 40 * 41 * Written by: 42 * J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc. 43 */ 44 45/* 46 * I've unrolled the loop eight times: large enough to make a 47 * significant difference, and small enough not to totally trash the 48 * cache. 49 */ 50 51ENTRY(strcmp) 52 movl 0x04(%esp),%eax 53 movl 0x08(%esp),%edx 54 jmp L2 /* Jump into the loop! */ 55 56 .align 2,0x90 57L1: incl %eax 58 incl %edx 59L2: movb (%eax),%cl 60 testb %cl,%cl 61 je L3 62 cmpb %cl,(%edx) 63 jne L3 64 incl %eax 65 incl %edx 66 movb (%eax),%cl 67 testb %cl,%cl 68 je L3 69 cmpb %cl,(%edx) 70 jne L3 71 incl %eax 72 incl %edx 73 movb (%eax),%cl 74 testb %cl,%cl 75 je L3 76 cmpb %cl,(%edx) 77 jne L3 78 incl %eax 79 incl %edx 80 movb (%eax),%cl 81 testb %cl,%cl 82 je L3 83 cmpb %cl,(%edx) 84 jne L3 85 incl %eax 86 incl %edx 87 movb (%eax),%cl 88 testb %cl,%cl 89 je L3 90 cmpb %cl,(%edx) 91 jne L3 92 incl %eax 93 incl %edx 94 movb (%eax),%cl 95 testb %cl,%cl 96 je L3 97 cmpb %cl,(%edx) 98 jne L3 99 incl %eax 100 incl %edx 101 movb (%eax),%cl 102 testb %cl,%cl 103 je L3 104 cmpb %cl,(%edx) 105 jne L3 106 incl %eax 107 incl %edx 108 movb (%eax),%cl 109 testb %cl,%cl 110 je L3 111 cmpb %cl,(%edx) 112 je L1 113 .align 2, 0x90 114L3: movzbl (%eax),%eax /* unsigned comparison */ 115 movzbl (%edx),%edx 116 subl %edx,%eax 117 ret 118END(strcmp) 119 120 .section .note.GNU-stack,"",%progbits 121