about summary refs log tree commit diff
path: root/REORG.TODO/sysdeps/i386/i686/memcpy.S
diff options
context:
space:
mode:
Diffstat (limited to 'REORG.TODO/sysdeps/i386/i686/memcpy.S')
-rw-r--r--REORG.TODO/sysdeps/i386/i686/memcpy.S98
1 files changed, 98 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/i386/i686/memcpy.S b/REORG.TODO/sysdeps/i386/i686/memcpy.S
new file mode 100644
index 0000000000..1d61447430
--- /dev/null
+++ b/REORG.TODO/sysdeps/i386/i686/memcpy.S
@@ -0,0 +1,98 @@
+/* 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) 1999-2017 Free Software Foundation, Inc.
+   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 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
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+#include "asm-syntax.h"
+
+#define PARMS	4		/* no space for saved regs */
+#define RTN	PARMS
+#define DEST	RTN
+#define SRC	DEST+4
+#define LEN	SRC+4
+
+	.text
+#if defined PIC && IS_IN (libc)
+ENTRY_CHK (__memcpy_chk)
+	movl	12(%esp), %eax
+	cmpl	%eax, 16(%esp)
+	jb	HIDDEN_JUMPTARGET (__chk_fail)
+END_CHK (__memcpy_chk)
+#endif
+ENTRY (memcpy)
+
+	movl	%edi, %eax
+	movl	DEST(%esp), %edi
+	movl	%esi, %edx
+	movl	SRC(%esp), %esi
+
+	movl	%edi, %ecx
+	xorl	%esi, %ecx
+	andl	$3, %ecx
+	movl	LEN(%esp), %ecx
+	cld
+	jne	.Lunaligned
+
+	cmpl	$3, %ecx
+	jbe	.Lunaligned
+
+	testl	$3, %esi
+	je	1f
+	movsb
+	decl	%ecx
+	testl	$3, %esi
+	je	1f
+	movsb
+	decl	%ecx
+	testl	$3, %esi
+	je	1f
+	movsb
+	decl	%ecx
+1:	pushl	%eax
+	movl	%ecx, %eax
+	shrl	$2, %ecx
+	andl	$3, %eax
+	rep
+	movsl
+	movl	%eax, %ecx
+	rep
+	movsb
+	popl	%eax
+
+.Lend:	movl	%eax, %edi
+	movl	%edx, %esi
+	movl	DEST(%esp), %eax
+
+	ret
+
+	/* When we come here the pointers do not have the same
+	   alignment or the length is too short.  No need to optimize for
+	   aligned memory accesses. */
+.Lunaligned:
+	shrl	$1, %ecx
+	jnc	1f
+	movsb
+1:	shrl	$1, %ecx
+	jnc	2f
+	movsw
+2:	rep
+	movsl
+	jmp	.Lend
+END (memcpy)
+libc_hidden_builtin_def (memcpy)