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/* Highly optimized version for ix86, x>=6.
Copyright (C) 1999, 2000, 2002, 2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1999.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include "asm-syntax.h"
#include "bp-sym.h"
#include "bp-asm.h"
#define PARMS LINKAGE /* no space for saved regs */
#define STR1 PARMS
#define STR2 STR1+PTR_SIZE
.text
ENTRY (BP_SYM (strcmp))
ENTER
movl STR1(%esp), %ecx
movl STR2(%esp), %edx
CHECK_BOUNDS_LOW (%ecx, STR1(%esp))
CHECK_BOUNDS_LOW (%edx, STR2(%esp))
L(oop): movb (%ecx), %al
cmpb (%edx), %al
jne L(neq)
incl %ecx
incl %edx
testb %al, %al
jnz L(oop)
xorl %eax, %eax
/* when strings are equal, pointers rest one beyond
the end of the NUL terminators. */
CHECK_BOUNDS_HIGH (%ecx, STR1(%esp), jbe)
CHECK_BOUNDS_HIGH (%edx, STR2(%esp), jbe)
LEAVE
ret
#ifndef __BOUNDED_POINTERS__
L(neq): movl $1, %eax
movl $-1, %ecx
cmovbl %ecx, %eax
#else
L(neq): movl $1, %eax
ja L(chk)
negl %eax
/* When strings differ, pointers rest on
the unequal characters. */
L(chk): CHECK_BOUNDS_HIGH (%ecx, STR1(%esp), jb)
CHECK_BOUNDS_HIGH (%edx, STR2(%esp), jb)
#endif
LEAVE
ret
END (BP_SYM (strcmp))
libc_hidden_builtin_def (strcmp)
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