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-rw-r--r--sysdeps/i386/i586/strcpy.S147
1 files changed, 147 insertions, 0 deletions
diff --git a/sysdeps/i386/i586/strcpy.S b/sysdeps/i386/i586/strcpy.S
new file mode 100644
index 0000000000..7f89a2c0f7
--- /dev/null
+++ b/sysdeps/i386/i586/strcpy.S
@@ -0,0 +1,147 @@
+/* strcpy/stpcpy implementation for i586.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  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"
+
+#ifndef USE_AS_STPCPY
+# define STRCPY strcpy
+#endif
+
+#define magic 0xfefefeff
+
+	.text
+ENTRY(STRCPY)
+	pushl	%edi
+	pushl	%esi
+	pushl	%ebx
+
+	movl	16(%esp), %edi
+	movl	20(%esp), %esi
+
+	xorl	%eax, %eax
+	leal	-1(%esi), %ecx
+
+	movl	$magic, %ebx
+	andl	$3, %ecx
+
+#ifdef PIC
+	call	2f
+2:	popl	%edx
+	/* 0xb is the distance between 2: and 1: but we avoid writing
+	   1f-2b because the assembler generates worse code.  */
+	leal	0xb(%edx,%ecx,8), %ecx
+#else
+	leal	1f(,%ecx,8), %ecx
+#endif
+
+	jmp	*%ecx
+
+	.align 8
+1:
+	orb	(%esi), %al
+	jz	L(end)
+	stosb
+	xorl	%eax, %eax
+	incl	%esi
+
+	orb	(%esi), %al
+	jz	L(end)
+	stosb
+	xorl	%eax, %eax
+	incl	%esi
+
+	orb	(%esi), %al
+	jz	L(end)
+	stosb
+	xorl	%eax, %eax
+	incl	%esi
+
+L(1):	movl	(%esi), %ecx
+	leal	4(%esi),%esi
+
+	subl	%ecx, %eax
+	addl	%ebx, %ecx
+
+	decl	%eax
+	jnc	L(3)
+
+	movl	%ecx, %edx
+	xorl	%ecx, %eax
+
+	subl	%ebx, %edx
+	andl	$~magic, %eax
+
+	jne	L(4)
+
+	movl	%edx, (%edi)
+	leal	4(%edi),%edi
+
+	jmp	L(1)
+
+L(3):	movl	%ecx, %edx
+
+	subl	%ebx, %edx
+
+L(4):	movb	%dl, (%edi)
+	testb	%dl, %dl
+
+	movl	%edx, %eax
+	jz	L(end2)
+
+	shrl	$16, %eax
+	movb	%dh, 1(%edi)
+#ifdef USE_AS_STPCPY
+	addl	$1, %edi
+#endif
+
+	cmpb	$0, %dh
+	jz	L(end2)
+
+#ifdef USE_AS_STPCPY
+	movb	%al, 1(%edi)
+	addl	$1, %edi
+
+	cmpb	$0, %al
+	jz	L(end2)
+
+	addl	$1, %edi
+#else
+	movb	%al, 2(%edi)
+	testb	%al, %al
+
+	leal	3(%edi), %edi
+	jz	L(end2)
+#endif
+
+L(end):	movb	%ah, (%edi)
+
+L(end2):
+#ifdef USE_AS_STPCPY
+	movl	%edi, %eax
+#endif
+	popl	%ebx
+	popl	%esi
+	popl	%edi
+#ifndef USE_AS_STPCPY
+	movl	4(%esp), %eax
+#endif
+	ret
+END(STRCPY)