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authorRoland McGrath <roland@gnu.org>1995-10-16 01:37:51 +0000
committerRoland McGrath <roland@gnu.org>1995-10-16 01:37:51 +0000
commit8f5ca04bc7fd53741d80117df992995ace8f6d2d (patch)
treee39c13fc198b22ec55647259a8080051988e8c69 /sysdeps/alpha/rshift.s
parent5d82cf5c55f56ae10d3b0a205d1fcc7de1cf56a0 (diff)
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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.
Diffstat (limited to 'sysdeps/alpha/rshift.s')
-rw-r--r--sysdeps/alpha/rshift.s106
1 files changed, 106 insertions, 0 deletions
diff --git a/sysdeps/alpha/rshift.s b/sysdeps/alpha/rshift.s
new file mode 100644
index 0000000000..74eab0434a
--- /dev/null
+++ b/sysdeps/alpha/rshift.s
@@ -0,0 +1,106 @@
+ # Alpha 21064 __mpn_rshift --
+
+ # Copyright (C) 1994, 1995 Free Software Foundation, Inc.
+
+ # This file is part of the GNU MP Library.
+
+ # The GNU MP 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 MP 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 MP Library; see the file COPYING.LIB.  If not, write to
+ # the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+
+ # INPUT PARAMETERS
+ # res_ptr	r16
+ # s1_ptr	r17
+ # size		r18
+ # cnt		r19
+
+ # This code runs at 4.8 cycles/limb on the 21064.  With infinite unrolling,
+ # it would take 4 cycles/limb.  It should be possible to get down to 3
+ # cycles/limb since both ldq and stq can be paired with the other used
+ # instructions.  But there are many restrictions in the 21064 pipeline that
+ # makes it hard, if not impossible, to get down to 3 cycles/limb:
+
+ # 1. ldq has a 3 cycle delay, srl and sll have a 2 cycle delay.
+ # 2. Only aligned instruction pairs can be paired.
+ # 3. The store buffer or silo might not be able to deal with the bandwidth.
+      
+	.set	noreorder
+	.set	noat
+.text
+	.align	3
+	.globl	__mpn_rshift
+	.ent	__mpn_rshift
+__mpn_rshift:
+	.frame	$30,0,$26,0
+
+	ldq	$4,0($17)	# load first limb
+	addq	$17,8,$17
+	subq	$31,$19,$7
+	subq	$18,1,$18
+	and	$18,4-1,$20	# number of limbs in first loop
+	sll	$4,$7,$0	# compute function result
+
+	beq	$20,L0
+	subq	$18,$20,$18
+
+	.align	3
+Loop0:
+	ldq	$3,0($17)
+	addq	$16,8,$16
+	addq	$17,8,$17
+	subq	$20,1,$20
+	srl	$4,$19,$5
+	sll	$3,$7,$6
+	bis	$3,$3,$4
+	bis	$5,$6,$8
+	stq	$8,-8($16)
+	bne	$20,Loop0
+
+L0:	beq	$18,Lend
+
+	.align	3
+Loop:	ldq	$3,0($17)
+	addq	$16,32,$16
+	subq	$18,4,$18
+	srl	$4,$19,$5
+	sll	$3,$7,$6
+
+	ldq	$4,8($17)
+	srl	$3,$19,$1
+	bis	$5,$6,$8
+	stq	$8,-32($16)
+	sll	$4,$7,$2
+
+	ldq	$3,16($17)
+	srl	$4,$19,$5
+	bis	$1,$2,$8
+	stq	$8,-24($16)
+	sll	$3,$7,$6
+
+	ldq	$4,24($17)
+	srl	$3,$19,$1
+	bis	$5,$6,$8
+	stq	$8,-16($16)
+	sll	$4,$7,$2
+
+	addq	$17,32,$17
+	bis	$1,$2,$8
+	stq	$8,-8($16)
+
+	bgt	$18,Loop
+
+Lend:	srl	$4,$19,$8
+	stq	$8,0($16)
+	ret	$31,($26),1
+	.end	__mpn_rshift