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+# IBM POWER __mpn_submul_1 -- Multiply a limb vector with a limb and subtract
+# the result from a second limb vector.
+
+# 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
+# s1_ptr	r4
+# size		r5
+# s2_limb	r6
+
+# The RS/6000 has no unsigned 32x32->64 bit multiplication instruction.  To
+# obtain that operation, we have to use the 32x32->64 signed multiplication
+# instruction, and add the appropriate compensation to the high limb of the
+# result.  We add the multiplicand if the multiplier has its most significant
+# bit set, and we add the multiplier if the multiplicand has its most
+# significant bit set.  We need to preserve the carry flag between each
+# iteration, so we have to compute the compensation carefully (the natural,
+# srai+and doesn't work).  Since the POWER architecture has a branch unit
+# we can branch in zero cycles, so that's how we perform the additions.
+
+	.toc
+	.csect .__mpn_submul_1[PR]
+	.align 2
+	.globl __mpn_submul_1
+	.globl .__mpn_submul_1
+	.csect __mpn_submul_1[DS]
+__mpn_submul_1:
+	.long .__mpn_submul_1[PR], TOC[tc0], 0
+	.csect .__mpn_submul_1[PR]
+.__mpn_submul_1:
+
+	cal	3,-4(3)
+	l	0,0(4)
+	cmpi	0,6,0
+	mtctr	5
+	mul	9,0,6
+	srai	7,0,31
+	and	7,7,6
+	mfmq	11
+	cax	9,9,7
+	l	7,4(3)
+	sf	8,11,7		# add res_limb
+	a	11,8,11		# invert cy (r11 is junk)
+	blt	Lneg
+Lpos:	bdz	Lend
+
+Lploop:	lu	0,4(4)
+	stu	8,4(3)
+	cmpi	0,0,0
+	mul	10,0,6
+	mfmq	0
+	ae	11,0,9		# low limb + old_cy_limb + old cy
+	l	7,4(3)
+	aze	10,10		# propagate cy to new cy_limb
+	sf	8,11,7		# add res_limb
+	a	11,8,11		# invert cy (r11 is junk)
+	bge	Lp0
+	cax	10,10,6		# adjust high limb for negative limb from s1
+Lp0:	bdz	Lend0
+	lu	0,4(4)
+	stu	8,4(3)
+	cmpi	0,0,0
+	mul	9,0,6
+	mfmq	0
+	ae	11,0,10
+	l	7,4(3)
+	aze	9,9
+	sf	8,11,7
+	a	11,8,11		# invert cy (r11 is junk)
+	bge	Lp1
+	cax	9,9,6		# adjust high limb for negative limb from s1
+Lp1:	bdn	Lploop
+
+	b	Lend
+
+Lneg:	cax	9,9,0
+	bdz	Lend
+Lnloop:	lu	0,4(4)
+	stu	8,4(3)
+	cmpi	0,0,0
+	mul	10,0,6
+	mfmq	7
+	ae	11,7,9
+	l	7,4(3)
+	ae	10,10,0		# propagate cy to new cy_limb
+	sf	8,11,7		# add res_limb
+	a	11,8,11		# invert cy (r11 is junk)
+	bge	Ln0
+	cax	10,10,6		# adjust high limb for negative limb from s1
+Ln0:	bdz	Lend0
+	lu	0,4(4)
+	stu	8,4(3)
+	cmpi	0,0,0
+	mul	9,0,6
+	mfmq	7
+	ae	11,7,10
+	l	7,4(3)
+	ae	9,9,0		# propagate cy to new cy_limb
+	sf	8,11,7		# add res_limb
+	a	11,8,11		# invert cy (r11 is junk)
+	bge	Ln1
+	cax	9,9,6		# adjust high limb for negative limb from s1
+Ln1:	bdn	Lnloop
+	b	Lend
+
+Lend0:	cal	9,0(10)
+Lend:	st	8,4(3)
+	aze	3,9
+	br