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-rw-r--r--sysdeps/i386/i686/memset.S75
1 files changed, 75 insertions, 0 deletions
diff --git a/sysdeps/i386/i686/memset.S b/sysdeps/i386/i686/memset.S
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+++ b/sysdeps/i386/i686/memset.S
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+/* memset/bzero -- set memory area to CH/0
+   Highly optimized version for ix86, x>=6.
+   Copyright (C) 1999 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   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"
+
+/*
+   INPUT PARAMETERS:
+   (memset)			(bzero)
+   dst          (sp + 4)	dst	(sp + 4)
+   ch           (sp + 8)	len	(sp + 8)
+   len		(sp + 12)
+*/
+
+
+        .text
+ENTRY (memset)
+	cld
+	pushl	%edi
+	movl	8(%esp), %edx
+#ifdef memset
+	movl	12(%esp), %ecx
+	xorl	%eax, %eax
+#else
+	movzbl	12(%esp), %eax
+	movl	16(%esp), %ecx
+#endif
+	jecxz	1f
+	movl	%edx, %edi
+	andl	$3, %edx
+	jz	2f
+	jnp	3f
+	stosb
+	decl	%ecx
+	jz	1f
+3:	stosb
+	decl	%ecx
+	jz	1f
+	xorl	$3, %edx
+	jz	2f
+	stosb
+	decl	%ecx
+2:	movl	%ecx, %edx
+	shrl	$2, %ecx
+	andl	$3, %edx
+#ifndef memset
+	imul	$0x01010101, %eax
+#endif
+	rep
+	stosl
+	movl	%edx, %ecx
+	rep
+	stosb
+
+1:	movl	8(%esp), %eax
+	popl	%edi
+	ret
+END (memset)