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/* strcpy/stpcpy implementation for i586.
Copyright (C) 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <sysdep.h>
#include "asm-syntax.h"
#ifndef USE_AS_STPCPY
# define STRCPY strcpy
#endif
#define magic 0xfefefeff
.text
ENTRY(STRCPY)
pushl %edi
pushl %esi
pushl %ebx
movl 16(%esp), %edi
movl 20(%esp), %esi
xorl %eax, %eax
leal -1(%esi), %ecx
movl $magic, %ebx
andl $3, %ecx
#ifdef PIC
call 2f
2: popl %edx
/* 0xb is the distance between 2: and 1: but we avoid writing
1f-2b because the assembler generates worse code. */
leal 0xb(%edx,%ecx,8), %ecx
#else
leal 1f(,%ecx,8), %ecx
#endif
jmp *%ecx
.align 8
1:
orb (%esi), %al
jz L(end)
stosb
xorl %eax, %eax
incl %esi
orb (%esi), %al
jz L(end)
stosb
xorl %eax, %eax
incl %esi
orb (%esi), %al
jz L(end)
stosb
xorl %eax, %eax
incl %esi
L(1): movl (%esi), %ecx
leal 4(%esi),%esi
subl %ecx, %eax
addl %ebx, %ecx
decl %eax
jnc L(3)
movl %ecx, %edx
xorl %ecx, %eax
subl %ebx, %edx
andl $~magic, %eax
jne L(4)
movl %edx, (%edi)
leal 4(%edi),%edi
jmp L(1)
L(3): movl %ecx, %edx
subl %ebx, %edx
L(4): movb %dl, (%edi)
testb %dl, %dl
movl %edx, %eax
jz L(end2)
shrl $16, %eax
movb %dh, 1(%edi)
#ifdef USE_AS_STPCPY
addl $1, %edi
#endif
cmpb $0, %dh
jz L(end2)
#ifdef USE_AS_STPCPY
movb %al, 1(%edi)
addl $1, %edi
cmpb $0, %al
jz L(end2)
addl $1, %edi
#else
movb %al, 2(%edi)
testb %al, %al
leal 3(%edi), %edi
jz L(end2)
#endif
L(end): movb %ah, (%edi)
L(end2):
#ifdef USE_AS_STPCPY
movl %edi, %eax
#endif
popl %ebx
popl %esi
popl %edi
#ifndef USE_AS_STPCPY
movl 4(%esp), %eax
#endif
ret
END(STRCPY)
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