| 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 withough 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 | * $Id: strcat.s,v 1.5 1993/08/16 17:06:37 jtc Exp $ |
| 31 | */ |
| 32 | |
| 33 | #if defined(LIBC_RCS) && !defined(lint) |
| 34 | .asciz "$Id: strcat.s,v 1.5 1993/08/16 17:06:37 jtc Exp $" |
| 35 | #endif /* LIBC_RCS and not lint */ |
| 36 | |
| 37 | #include "DEFS.h" |
| 38 | |
| 39 | /* |
| 40 | * strcat(s, append) |
| 41 | * append a copy of the null-terminated string "append" to the end |
| 42 | * of the null-terminated string s, then add a terminating `\0'. |
| 43 | * |
| 44 | * Written by: |
| 45 | * J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc. |
| 46 | */ |
| 47 | |
| 48 | /* |
| 49 | * I've unrolled the loop eight times: large enough to make a |
| 50 | * significant difference, and small enough not to totally trash the |
| 51 | * cashe. |
| 52 | */ |
| 53 | |
| 54 | ENTRY(strcat) |
| 55 | pushl %edi /* save edi */ |
| 56 | movl 8(%esp),%edi /* dst address */ |
| 57 | movl 12(%esp),%edx /* src address */ |
| 58 | pushl %edi /* push destination address */ |
| 59 | |
| 60 | cld /* set search forward */ |
| 61 | xorl %eax,%eax /* set search for null terminator */ |
| 62 | movl $-1,%ecx /* set search for lots of characters */ |
| 63 | repne /* search! */ |
| 64 | scasb |
| 65 | |
| 66 | leal -1(%edi),%ecx /* correct dst address */ |
| 67 | |
| 68 | .align 2,0x90 |
| 69 | L1: movb (%edx),%al /* unroll loop, but not too much */ |
| 70 | movb %al,(%ecx) |
| 71 | testb %al,%al |
| 72 | je L2 |
| 73 | movb 1(%edx),%al |
| 74 | movb %al,1(%ecx) |
| 75 | testb %al,%al |
| 76 | je L2 |
| 77 | movb 2(%edx),%al |
| 78 | movb %al,2(%ecx) |
| 79 | testb %al,%al |
| 80 | je L2 |
| 81 | movb 3(%edx),%al |
| 82 | movb %al,3(%ecx) |
| 83 | testb %al,%al |
| 84 | je L2 |
| 85 | movb 4(%edx),%al |
| 86 | movb %al,4(%ecx) |
| 87 | testb %al,%al |
| 88 | je L2 |
| 89 | movb 5(%edx),%al |
| 90 | movb %al,5(%ecx) |
| 91 | testb %al,%al |
| 92 | je L2 |
| 93 | movb 6(%edx),%al |
| 94 | movb %al,6(%ecx) |
| 95 | testb %al,%al |
| 96 | je L2 |
| 97 | movb 7(%edx),%al |
| 98 | movb %al,7(%ecx) |
| 99 | addl $8,%edx |
| 100 | addl $8,%ecx |
| 101 | testb %al,%al |
| 102 | jne L1 |
| 103 | L2: popl %eax /* pop destination address */ |
| 104 | popl %edi /* restore edi */ |
| 105 | ret |