mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-15 01:21:06 +00:00
100 lines
2.9 KiB
ArmAsm
100 lines
2.9 KiB
ArmAsm
;! 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) 1992-2016 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
|