about summary refs log tree commit diff
path: root/sysdeps/rs6000/rshift.s
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/rs6000/rshift.s')
-rw-r--r--sysdeps/rs6000/rshift.s56
1 files changed, 56 insertions, 0 deletions
diff --git a/sysdeps/rs6000/rshift.s b/sysdeps/rs6000/rshift.s
new file mode 100644
index 0000000000..6056acc753
--- /dev/null
+++ b/sysdeps/rs6000/rshift.s
@@ -0,0 +1,56 @@
+# IBM POWER __mpn_rshift -- 
+
+# Copyright (C) 1992, 1994 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	r3
+# s_ptr		r4
+# size		r5
+# cnt		r6
+
+	.toc
+	.extern __mpn_rshift[DS]
+	.extern .__mpn_rshift
+.csect [PR]
+	.align 2
+	.globl __mpn_rshift
+	.globl .__mpn_rshift
+	.csect __mpn_rshift[DS]
+__mpn_rshift:
+	.long .__mpn_rshift, TOC[tc0], 0
+	.csect [PR]
+.__mpn_rshift:
+	sfi	8,6,32
+	mtctr	5		# put limb count in CTR loop register
+	l	0,0(4)		# read least significant limb
+	ai	9,3,-4		# adjust res_ptr since it's offset in the stu:s
+	sle	3,0,8		# compute carry limb, and init MQ register
+	bdz	Lend2		# if just one limb, skip loop
+	lu	0,4(4)		# read 2:nd least significant limb
+	sleq	7,0,8		# compute least significant limb of result
+	bdz	Lend		# if just two limb, skip loop
+Loop:	lu	0,4(4)		# load next higher limb
+	stu	7,4(9)		# store previous result during read latency
+	sleq	7,0,8		# compute result limb
+	bdn	Loop		# loop back until CTR is zero
+Lend:	stu	7,4(9)		# store 2:nd most significant limb
+Lend2:	sre	7,0,6		# compute most significant limb
+	st      7,4(9)		# store it"				\
+	br