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/*
* 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("$FreeBSD$");
/*
* strcat(s, append)
* append a copy of the null-terminated string "append" to the end
* of the null-terminated string s, then add a terminating `\0'.
*
* 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(strcat)
pushl %edi /* save edi */
movl 8(%esp),%edi /* dst address */
movl 12(%esp),%edx /* src address */
pushl %edi /* push destination address */
cld /* set search forward */
xorl %eax,%eax /* set search for null terminator */
movl $-1,%ecx /* set search for lots of characters */
repne /* search! */
scasb
leal -1(%edi),%ecx /* correct dst address */
.align 2,0x90
L1: movb (%edx),%al /* unroll loop, but not too much */
movb %al,(%ecx)
testb %al,%al
je L2
movb 1(%edx),%al
movb %al,1(%ecx)
testb %al,%al
je L2
movb 2(%edx),%al
movb %al,2(%ecx)
testb %al,%al
je L2
movb 3(%edx),%al
movb %al,3(%ecx)
testb %al,%al
je L2
movb 4(%edx),%al
movb %al,4(%ecx)
testb %al,%al
je L2
movb 5(%edx),%al
movb %al,5(%ecx)
testb %al,%al
je L2
movb 6(%edx),%al
movb %al,6(%ecx)
testb %al,%al
je L2
movb 7(%edx),%al
movb %al,7(%ecx)
addl $8,%edx
addl $8,%ecx
testb %al,%al
jne L1
L2: popl %eax /* pop destination address */
popl %edi /* restore edi */
ret
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