mpir/mpn/pa32/hppa1_1/mul_1.asm

95 lines
2.8 KiB
NASM

dnl HP-PA 1.1 mpn_mul_1 -- Multiply a limb vector with a limb and store the
dnl result in a second limb vector.
dnl Copyright 1992, 1993, 1994, 2000, 2001, 2002 Free Software Foundation,
dnl Inc.
dnl This file is part of the GNU MP Library.
dnl The GNU MP Library is free software; you can redistribute it and/or modify
dnl it under the terms of the GNU Lesser General Public License as published
dnl by the Free Software Foundation; either version 2.1 of the License, or (at
dnl your option) any later version.
dnl The GNU MP Library is distributed in the hope that it will be useful, but
dnl WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
dnl or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
dnl License for more details.
dnl You should have received a copy of the GNU Lesser General Public License
dnl along with the GNU MP Library; see the file COPYING.LIB. If not, write
dnl to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
dnl Boston, MA 02110-1301, USA.
include(`../config.m4')
C INPUT PARAMETERS
C res_ptr r26
C s1_ptr r25
C size r24
C s2_limb r23
C This runs at 9 cycles/limb on a PA7000. With the used instructions, it can
C not become faster due to data cache contention after a store. On the PA7100
C it runs at 7 cycles/limb.
C We could use fldds to read two limbs at a time from the S1 array, and that
C could bring down the times to 8.5 and 6.5 cycles/limb for the PA7000 and
C PA7100, respectively. We don't do that since it does not seem worth the
C (alignment) troubles...
C At least the PA7100 is rumored to be able to deal with cache-misses without
C stalling instruction issue. If this is true, and the cache is actually also
C lockup-free, we should use a deeper software pipeline, and load from S1 very
C early! (The loads and stores to -12(sp) will surely be in the cache.)
ASM_START()
PROLOGUE(mpn_mul_1)
C .callinfo frame=64,no_calls
ldo 64(%r30),%r30
fldws,ma 4(%r25),%fr5
stw %r23,-16(%r30) C move s2_limb ...
addib,= -1,%r24,L(just_one_limb)
fldws -16(%r30),%fr4 C ... into fr4
add %r0,%r0,%r0 C clear carry
xmpyu %fr4,%fr5,%fr6
fldws,ma 4(%r25),%fr7
fstds %fr6,-16(%r30)
xmpyu %fr4,%fr7,%fr8
ldw -12(%r30),%r19 C least significant limb in product
ldw -16(%r30),%r28
fstds %fr8,-16(%r30)
addib,= -1,%r24,L(end)
ldw -12(%r30),%r1
C Main loop
LDEF(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
LDEF(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
LDEF(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)
EPILOGUE()