Sat Oct 14 02:52:36 1995 Ulrich Drepper <drepper@ipd.info.uni-karlsruhe.de>

	* malloc/malloc.c (_malloc_internal): Performance fix.  Move
	if statement out of loop.

	* stdio/_itoa.c, stdio/_itoa.h: Complete rewrite.  Much faster
	implementation using GMP functions.  Contributed by
	Torbjorn Granlund and Ulrich Drepper.

	* stdio/test_rdwr.c: Include <errno.h>.

	* sysdeps/i386/i586/Implies: New file.

	New highly optimized string functions for i[345]86.
	* sysdeps/i386/memchr.S, sysdeps/i386/memcmp.S: New files.
        * sysdeps/i386/stpcpy.S, sysdeps/i386/stpncpy.S: New files.
        * sysdeps/i386/strchr.S, sysdeps/i386/strcspn.S: New files.
        * sysdeps/i386/strpbrk.S, sysdeps/i386/strrchr.S: New files.
        * sysdeps/i386/strspn.S, sysdeps/i386/i486/strcat.S: New files.
        * sysdeps/i386/i486/strlen.S, sysdeps/i386/i586/strchr.S: New files.
        * sysdeps/i386/i586/strlen.S: New file.
	* sysdeps/i386/memchr.c: Removed.  There is now an assembler version.

	* sysdeps/i386/i586/memcopy.h (WORD_COPY_BWD): Parameters did
	not correspond to used values.

	* sysdeps/unix/sysv/linux/nfs/nfs.h: New file.  Simply a wrapper
        around a kernel header file.
	* sysdeps/unix/sysv/linux/Dist: Add it.
	* sysdeps/unix/sysv/linux/Makefile [$(subdir)=sunrpc] (headers):
	Likewise.

	* sysdeps/unix/sysv/linux/local_lim.h: Rewrite.  Instead of
        defining ourself we use a kernel header file.

	* sysdeps/unix/sysv/linux/i386/sysdep.h (DO_CALL): Optimize system
        call handler for i586.

	* sysdeps/unix/sysv/linux/sys/param.h: Add copyright and clean up.
Sat Oct 14 02:52:36 1995  Ulrich Drepper  <drepper@ipd.info.uni-karlsruhe.de>

	* malloc/malloc.c (_malloc_internal): Performance fix.  Move
	if statement out of loop.

	* stdio/_itoa.c, stdio/_itoa.h: Complete rewrite.  Much faster
	implementation using GMP functions.  Contributed by
	Torbjorn Granlund and Ulrich Drepper.

	* stdio/test_rdwr.c: Include <errno.h>.

	* sysdeps/i386/i586/Implies: New file.

	New highly optimized string functions for i[345]86.
	* sysdeps/i386/memchr.S, sysdeps/i386/memcmp.S: New files.
        * sysdeps/i386/stpcpy.S, sysdeps/i386/stpncpy.S: New files.
        * sysdeps/i386/strchr.S, sysdeps/i386/strcspn.S: New files.
        * sysdeps/i386/strpbrk.S, sysdeps/i386/strrchr.S: New files.
        * sysdeps/i386/strspn.S, sysdeps/i386/i486/strcat.S: New files.
        * sysdeps/i386/i486/strlen.S, sysdeps/i386/i586/strchr.S: New files.
        * sysdeps/i386/i586/strlen.S: New file.
	* sysdeps/i386/memchr.c: Removed.  There is now an assembler version.

	* sysdeps/i386/i586/memcopy.h (WORD_COPY_BWD): Parameters did
	not correspond to used values.

	* sysdeps/unix/sysv/linux/nfs/nfs.h: New file.  Simply a wrapper
        around a kernel header file.
	* sysdeps/unix/sysv/linux/Dist: Add it.
	* sysdeps/unix/sysv/linux/Makefile [$(subdir)=sunrpc] (headers):
	Likewise.

	* sysdeps/unix/sysv/linux/local_lim.h: Rewrite.  Instead of
        defining ourself we use a kernel header file.

	* sysdeps/unix/sysv/linux/i386/sysdep.h (DO_CALL): Optimize system
        call handler for i586.

	* sysdeps/unix/sysv/linux/sys/param.h: Add copyright and clean up.

1 files changed, 132 insertions, 0 deletions

diff --git a/sysdeps/i386/i486/strlen.S b/sysdeps/i386/i486/strlen.S
new file mode 100644
index 0000000000..276563b11a
--- /dev/null
+++ b/sysdeps/i386/i486/strlen.S
@@ -0,0 +1,132 @@
+/* strlen(str) -- determine the length of the string STR.
+Optimized for Intel 80x86, x>=4.
+Copyright (C) 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
+Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>.
+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:
+   str		(sp + 4)
+*/
+
+	.text
+ENTRY (strlen)
+	movl 4(%esp), %ecx	/* get string pointer */
+	movl %ecx, %eax		/* duplicate it */
+
+	andl $3, %ecx		/* mask alignment bits */
+	jz L1			/* aligned => start loop */
+	cmpb %ch, (%eax)	/* is byte NUL? */
+	je L2			/* yes => return */
+	incl %eax		/* increment pointer */
+
+	xorl $3, %ecx		/* was alignment = 3? */
+	jz L1			/* yes => now it is aligned and start loop */
+	cmpb %ch, (%eax)	/* is byte NUL? */
+	je L2			/* yes => return */
+	addl $1, %eax		/* increment pointer */
+
+	subl $1, %ecx		/* was alignment = 2? */
+	jz L1			/* yes => now it is aligned and start loop */
+	cmpb %ch, (%eax)	/* is byte NUL? */
+	je L2			/* yes => return */
+
+/* Don't change the above `addl $1,%eax' and `subl $1, %ecx' into `incl %eax'
+   and `decl %ecx' resp.  The additional two byte per instruction make the
+   label 4 to be aligned on a 16 byte boundary with nops.
+
+   The following `sub $15, %eax' is part of this trick, too.  Together with
+   the next instruction (`addl $16, %eax') it is in fact a `incl %eax', just
+   as expected from the algorithm.  But doing so has the advantage that
+   no jump to label 1 is necessary and so the pipeline is not flushed.  */
+
+	subl $15, %eax		/* effectively +1 */
+
+
+L4:	addl $16, %eax		/* adjust pointer for full loop */
+
+L1:	movl (%eax), %ecx	/* get word (= 4 bytes) in question */
+	movl $0xfefefeff, %edx	/* magic value */
+	addl %ecx, %edx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc L3			/* highest byte is NUL => return pointer */
+	xorl %ecx, %edx		/* (word+magic)^word */
+	orl $0xfefefeff, %edx	/* set all non-carry bits */
+	incl %edx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz L3			/* found NUL => return pointer */
+
+	movl 4(%eax), %ecx	/* get word (= 4 bytes) in question */
+	movl $0xfefefeff, %edx	/* magic value */
+	addl %ecx, %edx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc L5			/* highest byte is NUL => return pointer */
+	xorl %ecx, %edx		/* (word+magic)^word */
+	orl $0xfefefeff, %edx	/* set all non-carry bits */
+	incl %edx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz L5			/* found NUL => return pointer */
+
+	movl 8(%eax), %ecx	/* get word (= 4 bytes) in question */
+	movl $0xfefefeff, %edx	/* magic value */
+	addl %ecx, %edx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc L6			/* highest byte is NUL => return pointer */
+	xorl %ecx, %edx		/* (word+magic)^word */
+	orl $0xfefefeff, %edx	/* set all non-carry bits */
+	incl %edx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jnz L6			/* found NUL => return pointer */
+
+	movl 12(%eax), %ecx	/* get word (= 4 bytes) in question */
+	movl $0xfefefeff, %edx	/* magic value */
+	addl %ecx, %edx		/* add the magic value to the word.  We get
+				   carry bits reported for each byte which
+				   is *not* 0 */
+	jnc L7			/* highest byte is NUL => return pointer */
+	xorl %ecx, %edx		/* (word+magic)^word */
+	orl $0xfefefeff, %edx	/* set all non-carry bits */
+	incl %edx		/* add 1: if one carry bit was *not* set
+				   the addition will not result in 0.  */
+	jz L4			/* no NUL found => continue loop */
+
+L7:	addl $4, %eax		/* adjust pointer */
+L6:	addl $4, %eax
+L5:	addl $4, %eax
+
+L3:	testb %cl, %cl		/* is first byte NUL? */
+	jz L2			/* yes => return */
+	incl %eax		/* increment pointer */
+
+	testb %ch, %ch		/* is second byte NUL? */
+	jz L2			/* yes => return */
+	incl %eax		/* increment pointer */
+
+	testl $0xff0000, %ecx	/* is third byte NUL? */
+	jz L2			/* yes => return pointer */
+	incl %eax		/* increment pointer */
+
+L2:	subl 4(%esp), %eax	/* compute difference to string start */
+
+	ret