glibc/sysdeps/i386/i586/memcpy.S
Siddhesh Poyarekar 30891f35fa Remove "Contributed by" lines
We stopped adding "Contributed by" or similar lines in sources in 2012
in favour of git logs and keeping the Contributors section of the
glibc manual up to date.  Removing these lines makes the license
header a bit more consistent across files and also removes the
possibility of error in attribution when license blocks or files are
copied across since the contributed-by lines don't actually reflect
reality in those cases.

Move all "Contributed by" and similar lines (Written by, Test by,
etc.) into a new file CONTRIBUTED-BY to retain record of these
contributions.  These contributors are also mentioned in
manual/contrib.texi, so we just maintain this additional record as a
courtesy to the earlier developers.

The following scripts were used to filter a list of files to edit in
place and to clean up the CONTRIBUTED-BY file respectively.  These
were not added to the glibc sources because they're not expected to be
of any use in future given that this is a one time task:

https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dc
https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-09-03 22:06:44 +05:30

124 lines
2.7 KiB
ArmAsm

/* Highly optimized version for i586.
Copyright (C) 1997-2021 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+8 /* space for 2 saved regs */
#define RTN PARMS
#define DEST RTN
#define SRC DEST+4
#define LEN SRC+4
.text
#if defined PIC && IS_IN (libc)
ENTRY (__memcpy_chk)
movl 12(%esp), %eax
cmpl %eax, 16(%esp)
jb HIDDEN_JUMPTARGET (__chk_fail)
END (__memcpy_chk)
#endif
ENTRY (memcpy)
pushl %edi
cfi_adjust_cfa_offset (4)
pushl %esi
cfi_adjust_cfa_offset (4)
movl DEST(%esp), %edi
cfi_rel_offset (edi, 4)
movl SRC(%esp), %esi
cfi_rel_offset (esi, 0)
movl LEN(%esp), %ecx
movl %edi, %eax
/* We need this in any case. */
cld
/* Cutoff for the big loop is a size of 32 bytes since otherwise
the loop will never be entered. */
cmpl $32, %ecx
jbe L(1)
negl %eax
andl $3, %eax
subl %eax, %ecx
xchgl %eax, %ecx
rep; movsb
movl %eax, %ecx
subl $32, %ecx
js L(2)
/* Read ahead to make sure we write in the cache since the stupid
i586 designers haven't implemented read-on-write-miss. */
movl (%edi), %eax
L(3): movl 28(%edi), %edx
/* Now correct the loop counter. Please note that in the following
code the flags are not changed anymore. */
subl $32, %ecx
movl (%esi), %eax
movl 4(%esi), %edx
movl %eax, (%edi)
movl %edx, 4(%edi)
movl 8(%esi), %eax
movl 12(%esi), %edx
movl %eax, 8(%edi)
movl %edx, 12(%edi)
movl 16(%esi), %eax
movl 20(%esi), %edx
movl %eax, 16(%edi)
movl %edx, 20(%edi)
movl 24(%esi), %eax
movl 28(%esi), %edx
movl %eax, 24(%edi)
movl %edx, 28(%edi)
leal 32(%esi), %esi
leal 32(%edi), %edi
jns L(3)
/* Correct extra loop counter modification. */
L(2): addl $32, %ecx
#ifndef USE_AS_MEMPCPY
movl DEST(%esp), %eax
#endif
L(1): rep; movsb
#ifdef USE_AS_MEMPCPY
movl %edi, %eax
#endif
popl %esi
cfi_adjust_cfa_offset (-4)
cfi_restore (esi)
popl %edi
cfi_adjust_cfa_offset (-4)
cfi_restore (edi)
ret
END (memcpy)
#ifndef USE_AS_MEMPCPY
libc_hidden_builtin_def (memcpy)
#endif