memmove for i686.

1 files changed, 94 insertions, 0 deletions

diff --git a/sysdeps/i386/i686/memmove.S b/sysdeps/i386/i686/memmove.S
new file mode 100644
index 0000000..76fda40
--- /dev/null
+++ b/sysdeps/i386/i686/memmove.S
@@ -0,0 +1,94 @@
+/* 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))