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+# IBM POWER __mpn_addmul_1 -- Multiply a limb vector with a limb and add
+# the result to 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 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; see the file COPYING.LIB. If not, write to
+# the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+# MA 02111-1307, 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_addmul_1[PR]
+ .align 2
+ .globl __mpn_addmul_1
+ .globl .__mpn_addmul_1
+ .csect __mpn_addmul_1[DS]
+__mpn_addmul_1:
+ .long .__mpn_addmul_1[PR], TOC[tc0], 0
+ .csect .__mpn_addmul_1[PR]
+.__mpn_addmul_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 8
+ cax 9,9,7
+ l 7,4(3)
+ a 8,8,7 # add res_limb
+ 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 8,0,9 # low limb + old_cy_limb + old cy
+ l 7,4(3)
+ aze 10,10 # propagate cy to new cy_limb
+ a 8,8,7 # add res_limb
+ 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 8,0,10
+ l 7,4(3)
+ aze 9,9
+ a 8,8,7
+ 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 8,7,9
+ l 7,4(3)
+ ae 10,10,0 # propagate cy to new cy_limb
+ a 8,8,7 # add res_limb
+ 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 8,7,10
+ l 7,4(3)
+ ae 9,9,0 # propagate cy to new cy_limb
+ a 8,8,7 # add res_limb
+ 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