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-rw-r--r--sysdeps/i386/i586/memset.S101
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diff --git a/sysdeps/i386/i586/memset.S b/sysdeps/i386/i586/memset.S
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+/* memset/bzero -- set memory area to CH/0
+Highly optimized version for ix85, x>=5.
+Copyright (C) 1996 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+Contributed by Torbjorn Granlund, <tege@matematik.su.se>
+
+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>
+
+/*
+   INPUT PARAMETERS:
+   (memset)			(bzero)
+   dst          (sp + 4)	dst	(sp + 4)
+   ch           (sp + 8)	len	(sp + 8)
+   len		(sp + 12)
+*/
+
+
+        .text
+ENTRY (memset)
+	pushl	%edi
+
+	movl	8(%esp), %edi	/* destination pointer */
+#ifdef memset
+	xorl	%eax, %eax	/* we fill with 0 */
+	movl	12(%esp), %edx	/* size (in 8-bit words) */
+#else
+	movb	12(%esp), %al	/* use CH to fill */
+	movl	16(%esp), %edx	/* size (in 8-bit words) */
+
+	movb	%al, %ah
+	movl	%eax, %ecx
+	shll	$16, %eax
+	movw	%cx, %ax
+#endif
+	cld
+
+/* If less than 36 bytes to write, skip tricky code (it wouldn't work).  */
+	cmpl	$36, %edx
+	movl	%edx, %ecx	/* needed when branch is taken! */
+	jl	L2
+
+/* First write 0-3 bytes to make the pointer 32-bit aligned.  */
+	movl	%edi, %ecx	/* Copy ptr to ecx... */
+	negl	%ecx		/* ...and negate that and... */
+	andl	$3, %ecx	/* ...mask to get byte count.  */
+	subl	%ecx, %edx	/* adjust global byte count */
+	rep
+	stosb
+
+	subl	$32, %edx	/* offset count for unrolled loop */
+	movl	(%edi), %ecx	/* Fetch destination cache line */
+
+	.align	2, 0x90		/* supply 0x90 for broken assemblers */
+L1:	movl	28(%edi), %ecx	/* allocate cache line for destination */
+	subl	$32, %edx	/* decr loop count */
+	movl	%eax, 0(%edi)	/* store words pairwise */
+	movl	%eax, 4(%edi)
+	movl	%eax, 8(%edi)
+	movl	%eax, 12(%edi)
+	movl	%eax, 16(%edi)
+	movl	%eax, 20(%edi)
+	movl	%eax, 24(%edi)
+	movl	%eax, 28(%edi)
+	leal	32(%edi), %edi	/* update destination pointer */
+	jge	L1
+
+	leal	32(%edx), %ecx	/* reset offset count */
+
+/* Write last 0-7 full 32-bit words (up to 8 words if loop was skipped).  */
+L2:	shrl	$2, %ecx	/* convert byte count to longword count */
+	rep
+	stosl
+
+/* Finally write the last 0-3 bytes.  */
+	movl	%edx, %ecx
+	andl	$3, %ecx
+	rep
+	stosb
+
+	/* Load result (only if used as memset).  */
+#ifndef memset
+	movl	8(%esp), %eax
+#endif
+	popl	%edi
+
+	ret