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+;! HP-PA-1.1 __mpn_mul_1 -- Multiply a limb vector with a limb and store
+;! the result in a second limb vector.
+
+;! Copyright (C) 1992-2014 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 Lesser General Public License as published by
+;! the Free Software Foundation; either version 2.1 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 Lesser General Public
+;! License for more details.
+
+;! You should have received a copy of the GNU Lesser General Public License
+;! along with the GNU MP Library.  If not, see
+;! <http://www.gnu.org/licenses/>.
+
+
+;! INPUT PARAMETERS
+;! res_ptr	r26
+;! s1_ptr	r25
+;! size		r24
+;! s2_limb	r23
+
+;! This runs at 9 cycles/limb on a PA7000.  With the used instructions, it can
+;! not become faster due to data cache contention after a store.  On the
+;! PA7100 it runs at 7 cycles/limb, and that can not be improved either, since
+;! only the xmpyu does not need the integer pipeline, so the only dual-issue
+;! we will get are addc+xmpyu.  Unrolling would not help either CPU.
+
+;! We could use fldds to read two limbs at a time from the S1 array, and that
+;! could bring down the times to 8.5 and 6.5 cycles/limb for the PA7000 and
+;! PA7100, respectively.  We don't do that since it does not seem worth the
+;! (alignment) troubles...
+
+;! At least the PA7100 is rumored to be able to deal with cache-misses
+;! without stalling instruction issue.  If this is true, and the cache is
+;! actually also lockup-free, we should use a deeper software pipeline, and
+;! load from S1 very early;  (The loads and stores to -12(sp) will surely be
+;! in the cache.)
+
+	.text
+	.export		__mpn_mul_1
+__mpn_mul_1:
+	.proc
+	.callinfo	frame=64,no_calls
+	.entry
+
+	ldo		64(%r30),%r30
+	fldws,ma	4(%r25),%fr5
+	stw		%r23,-16(%r30)		;! move s2_limb ...
+	addib,=		-1,%r24,L$just_one_limb
+	 fldws		-16(%r30),%fr4		;! ... into fr4
+	add		%r0,%r0,%r0		;! clear carry
+	xmpyu		%fr4,%fr5,%fr6
+	fldws,ma	4(%r25),%fr7
+	fstds	 	%fr6,-16(%r30)
+	xmpyu		%fr4,%fr7,%fr8
+	ldw		-12(%r30),%r20		;! least significant limb in product
+	ldw		-16(%r30),%r28
+
+	fstds		%fr8,-16(%r30)
+	addib,=		-1,%r24,L$end
+	 ldw		-12(%r30),%r1
+
+;! Main loop
+L$loop:
+	fldws,ma	4(%r25),%fr5
+	stws,ma		%r20,4(%r26)
+	addc		%r28,%r1,%r20
+	xmpyu		%fr4,%fr5,%fr6
+	ldw		-16(%r30),%r28
+	fstds		%fr6,-16(%r30)
+	addib,<>	-1,%r24,L$loop
+	 ldw		-12(%r30),%r1
+
+L$end:
+	stws,ma		%r20,4(%r26)
+	addc		%r28,%r1,%r20
+	ldw		-16(%r30),%r28
+	stws,ma		%r20,4(%r26)
+	addc		%r0,%r28,%r28
+	bv		0(%r2)
+	 ldo		-64(%r30),%r30
+
+L$just_one_limb:
+	xmpyu		%fr4,%fr5,%fr6
+	fstds		%fr6,-16(%r30)
+	ldw		-16(%r30),%r28
+	ldo		-64(%r30),%r30
+	bv		0(%r2)
+	 fstws		%fr6R,0(%r26)
+
+	.exit
+	.procend