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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)