; HP-PA-1.1 __gmpn_mul_1 -- Multiply a limb vector with a limb and store ; the result in a second limb vector. ; Copyright (C) 1992, 1993, 1994, 2000 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., 59 Temple Place - Suite 330, Boston, ; MA 02111-1307, USA. ; 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.) .code .export __gmpn_mul_1 __gmpn_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$just_one_limb fldws -16(%r30),%fr4 ; ... into fr4 add %r0,%r0,%r0 ; clear carry xmpyu %fr4,%fr5,%fr6 fldws,ma 4(%r25),%fr7 fstds %fr6,-16(%r30) xmpyu %fr4,%fr7,%fr8 ldw -12(%r30),%r19 ; least significant limb in product ldw -16(%r30),%r28 fstds %fr8,-16(%r30) addib,= -1,%r24,L$end ldw -12(%r30),%r1 ; Main loop L$loop fldws,ma 4(%r25),%fr5 stws,ma %r19,4(%r26) addc %r28,%r1,%r19 xmpyu %fr4,%fr5,%fr6 ldw -16(%r30),%r28 fstds %fr6,-16(%r30) addib,<> -1,%r24,L$loop ldw -12(%r30),%r1 L$end stws,ma %r19,4(%r26) addc %r28,%r1,%r19 ldw -16(%r30),%r28 stws,ma %r19,4(%r26) addc %r0,%r28,%r28 bv 0(%r2) ldo -64(%r30),%r30 L$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