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authorRoland McGrath <roland@gnu.org>1996-03-27 23:23:59 +0000
committerRoland McGrath <roland@gnu.org>1996-03-27 23:23:59 +0000
commit53f770e0f9d405ea8d1888254c6f7ce431b04c6e (patch)
tree5f70c2032007667e315d94e29320f2c8d650f448 /sysdeps/i386/i586/memset.S
parent3ef987a23c3d81079cfccdc217997a13fd9c1cd1 (diff)
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Wed Mar 27 14:52:11 1996 Roland McGrath <roland@charlie-brown.gnu.ai.mit.edu>
	* elf/rtld.c (dl_main): Call _dl_sysdep_start_cleanup after
	_dl_relocate_object loop.  Avoid relocating RTLD_MAP in that loop, and
	do it individually if necessary after _dl_sysdep_start_cleanup call.

	* stdlib/Makefile (mpn-routines): Add divrem.

Tue Mar 26 22:54:14  Ulrich Drepper  <drepper@gnu.ai.mit.edu>

	* stdio-common/printf_fp.c (__printf_fp): Use mpn_divmod
	instead of __mpn_divmod.

Wed Mar 27 10:26:21 1996  David Mosberger-Tang  <davidm@azstarnet.com>

	* sysdeps/alpha/setjmp.S: Must establish global pointer before
 	address of __sigsetjmp_aux can be loaded.

Wed Mar 27 02:23:19 1996 Ulrich Drepper <drepper@gnu.ai.mit.edu>

	* sysdeps/i386/i586/memset.S: New file.  Highly optimized
	version for i586 contributed by Torbjorn Granlund.
	Adapted for use as bzero.
	* sysdeps/i386/i586/bzero.S: Use sysdeps/i386/i586/memset.S
	code to implement bzero().

Tue Mar 26 20:01:17 1996  Roland McGrath  <roland@charlie-brown.gnu.ai.mit.edu>

	* stdlib/Makefile (mpn-routines): Remove divmod.
Diffstat (limited to 'sysdeps/i386/i586/memset.S')
-rw-r--r--sysdeps/i386/i586/memset.S101
1 files changed, 101 insertions, 0 deletions
diff --git a/sysdeps/i386/i586/memset.S b/sysdeps/i386/i586/memset.S
new file mode 100644
index 0000000000..3a68fa16d1
--- /dev/null
+++ b/sysdeps/i386/i586/memset.S
@@ -0,0 +1,101 @@
+/* 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