glibc/sysdeps/i386/i686/memset.S
Paul Eggert 581c785bf3 Update copyright dates with scripts/update-copyrights
I used these shell commands:

../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")

and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.

I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah.  I don't
know why I run into these diagnostics whereas others evidently do not.

remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
2022-01-01 11:40:24 -08:00

93 lines
2.2 KiB
ArmAsm

/* memset/bzero -- set memory area to CH/0
Highly optimized version for ix86, x>=6.
Copyright (C) 1999-2022 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include "asm-syntax.h"
#define PARMS 4+4 /* space for 1 saved reg */
#ifdef USE_AS_BZERO
# define DEST PARMS
# define LEN DEST+4
#else
# define RTN PARMS
# define DEST RTN
# define CHR DEST+4
# define LEN CHR+4
#endif
.text
#if defined SHARED && IS_IN (libc) && !defined USE_AS_BZERO
ENTRY_CHK (__memset_chk)
movl 12(%esp), %eax
cmpl %eax, 16(%esp)
jb HIDDEN_JUMPTARGET (__chk_fail)
END_CHK (__memset_chk)
#endif
ENTRY (memset)
cld
pushl %edi
cfi_adjust_cfa_offset (4)
movl DEST(%esp), %edx
movl LEN(%esp), %ecx
#ifdef USE_AS_BZERO
xorl %eax, %eax /* fill with 0 */
#else
movzbl CHR(%esp), %eax
#endif
jecxz 1f
movl %edx, %edi
cfi_rel_offset (edi, 0)
andl $3, %edx
jz 2f /* aligned */
jp 3f /* misaligned at 3, store just one byte below */
stosb /* misaligned at 1 or 2, store two bytes */
decl %ecx
jz 1f
3: stosb
decl %ecx
jz 1f
xorl $1, %edx
jnz 2f /* was misaligned at 2 or 3, now aligned */
stosb /* was misaligned at 1, store third byte */
decl %ecx
2: movl %ecx, %edx
shrl $2, %ecx
andl $3, %edx
#ifndef USE_AS_BZERO
imul $0x01010101, %eax
#endif
rep
stosl
movl %edx, %ecx
rep
stosb
1:
#ifndef USE_AS_BZERO
movl DEST(%esp), %eax /* start address of destination is result */
#endif
popl %edi
cfi_adjust_cfa_offset (-4)
cfi_restore (edi)
ret
END (memset)
libc_hidden_builtin_def (memset)