glibc/sysdeps/i386/i686/memmove.S
2003-02-04 07:51:36 +00:00

95 lines
2.0 KiB
ArmAsm

/* Copy memory block and return pointer to beginning of destination block
For Intel 80x86, x>=6.
This file is part of the GNU C Library.
Copyright (C) 2003 Free Software Foundation, Inc.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 2003.
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, 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-sym.h"
#include "bp-asm.h"
#define PARMS LINKAGE+4 /* one spilled register */
#define RTN PARMS
#define DEST RTN+RTN_SIZE
#define SRC DEST+PTR_SIZE
#define LEN SRC+PTR_SIZE
.text
ENTRY (BP_SYM (memmove))
ENTER
pushl %edi
movl LEN(%esp), %ecx
movl DEST(%esp), %edi
movl %esi, %edx
movl SRC(%esp), %esi
CHECK_BOUNDS_BOTH_WIDE (%edi, DEST(%esp), %ecx)
CHECK_BOUNDS_BOTH_WIDE (%esi, SRC(%esp), %ecx)
movl %edi, %eax
subl %esi, %eax
cmpl %eax, %edi
jae 3f
cld
shrl $1, %ecx
jnc 1f
movsb
1: shrl $1, %ecx
jnc 2f
movsw
2: rep
movsl
movl %edx, %esi
movl DEST(%esp), %eax
RETURN_BOUNDED_POINTER (DEST(%esp))
popl %edi
LEAVE
RET_PTR
/* Backward copying. */
3: std
leal -1(%edi, %ecx), %edi
leal -1(%esi, %ecx), %esi
shrl $1, %ecx
jnc 1f
movsb
1: subl $1, %edi
subl $1, %esi
shrl $1, %ecx
jnc 2f
movsw
2: subl $2, %edi
subl $2, %esi
rep
movsl
movl %edx, %esi
movl DEST(%esp), %eax
RETURN_BOUNDED_POINTER (DEST(%esp))
cld
popl %edi
LEAVE
RET_PTR
END (BP_SYM (memmove))