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 * strcat(s, append) 34 * append a copy of the null-terminated string "append" to the end 35 * of the null-terminated string s, then add a terminating `\0'. 36 * 37 * Written by: 38 * J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc. 39 */ 40 41/* 42 * I've unrolled the loop eight times: large enough to make a 43 * significant difference, and small enough not to totally trash the 44 * cache. 45 */ 46 47ENTRY(strcat) 48 pushl %edi /* save edi */ 49 movl 8(%esp),%edi /* dst address */ 50 movl 12(%esp),%edx /* src address */ 51 pushl %edi /* push destination address */ 52 53 cld /* set search forward */ 54 xorl %eax,%eax /* set search for null terminator */ 55 movl $-1,%ecx /* set search for lots of characters */ 56 repne /* search! */ 57 scasb 58 59 leal -1(%edi),%ecx /* correct dst address */ 60 61 .align 2,0x90 62L1: movb (%edx),%al /* unroll loop, but not too much */ 63 movb %al,(%ecx) 64 testb %al,%al 65 je L2 66 movb 1(%edx),%al 67 movb %al,1(%ecx) 68 testb %al,%al 69 je L2 70 movb 2(%edx),%al 71 movb %al,2(%ecx) 72 testb %al,%al 73 je L2 74 movb 3(%edx),%al 75 movb %al,3(%ecx) 76 testb %al,%al 77 je L2 78 movb 4(%edx),%al 79 movb %al,4(%ecx) 80 testb %al,%al 81 je L2 82 movb 5(%edx),%al 83 movb %al,5(%ecx) 84 testb %al,%al 85 je L2 86 movb 6(%edx),%al 87 movb %al,6(%ecx) 88 testb %al,%al 89 je L2 90 movb 7(%edx),%al 91 movb %al,7(%ecx) 92 addl $8,%edx 93 addl $8,%ecx 94 testb %al,%al 95 jne L1 96L2: popl %eax /* pop destination address */ 97 popl %edi /* restore edi */ 98 ret 99END(strcat) 100 101 .section .note.GNU-stack,"",%progbits 102