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/* memset/bzero -- set memory area to CH/0
Highly optimized version for ix86, x>=6.
Copyright (C) 1999, 2000 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 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"
#include "bp-asm.h"
/* BEWARE: `#ifdef memset' means that memset is redefined as `bzero' */
#define BZERO_P (defined memset)
#define PARMS LINKAGE+4 /* space for 1 saved reg */
#if BZERO_P
# define DEST PARMS
# define LEN DEST+PTR_SIZE
#else
# define RTN PARMS
# define DEST RTN+RTN_SIZE
# define CHR DEST+PTR_SIZE
# define LEN CHR+4
#endif
.text
ENTRY (memset)
ENTER
cld
pushl %edi
movl DEST(%esp), %edx
movl LEN(%esp), %ecx
#if BZERO_P
xorl %eax, %eax /* fill with 0 */
#else
movzbl CHR(%esp), %eax
#endif
jecxz 1f
movl %edx, %edi
andl $3, %edx
jz 2f
jnp 3f
stosb
decl %ecx
jz 1f
3: stosb
decl %ecx
jz 1f
xorl $3, %edx
jz 2f
stosb
decl %ecx
2: movl %ecx, %edx
shrl $2, %ecx
andl $3, %edx
#if !BZERO_P
imul $0x01010101, %eax
#endif
rep
stosl
movl %edx, %ecx
rep
stosb
1:
#if !BZERO_P
movl DEST(%esp), %eax
#endif
popl %edi
LEAVE
#if BZERO_P
ret
#else
RET_PTR
#endif
END (memset)
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