84 lines
2.6 KiB
ArmAsm
84 lines
2.6 KiB
ArmAsm
|
# Alpha 21064 __mpn_mul_1 -- Multiply a limb vector with a limb and store
|
||
|
|
# the result in a second limb vector.
|
||
|
|
|
||
|
|
# Copyright (C) 1992-2022 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 <https://www.gnu.org/licenses/>.
|
||
|
|
|
||
|
|
|
||
|
|
# INPUT PARAMETERS
|
||
|
|
# res_ptr r16
|
||
|
|
# s1_ptr r17
|
||
|
|
# size r18
|
||
|
|
# s2_limb r19
|
||
|
|
|
||
|
|
# This code runs at 42 cycles/limb on the EV4 and 18 cycles/limb on the EV5.
|
||
|
|
|
||
|
|
# To improve performance for long multiplications, we would use
|
||
|
|
# 'fetch' for S1 and 'fetch_m' for RES. It's not obvious how to use
|
||
|
|
# these instructions without slowing down the general code: 1. We can
|
||
|
|
# only have two prefetches in operation at any time in the Alpha
|
||
|
|
# architecture. 2. There will seldom be any special alignment
|
||
|
|
# between RES_PTR and S1_PTR. Maybe we can simply divide the current
|
||
|
|
# loop into an inner and outer loop, having the inner loop handle
|
||
|
|
# exactly one prefetch block?
|
||
|
|
|
||
|
|
.set noreorder
|
||
|
|
.set noat
|
||
|
|
.text
|
||
|
|
.align 3
|
||
|
|
.globl __mpn_mul_1
|
||
|
|
.ent __mpn_mul_1 2
|
||
|
|
__mpn_mul_1:
|
||
|
|
.frame $30,0,$26
|
||
|
|
|
||
|
|
ldq $2,0($17) # $2 = s1_limb
|
||
|
|
subq $18,1,$18 # size--
|
||
|
|
mulq $2,$19,$3 # $3 = prod_low
|
||
|
|
bic $31,$31,$4 # clear cy_limb
|
||
|
|
umulh $2,$19,$0 # $0 = prod_high
|
||
|
|
beq $18,Lend1 # jump if size was == 1
|
||
|
|
ldq $2,8($17) # $2 = s1_limb
|
||
|
|
subq $18,1,$18 # size--
|
||
|
|
stq $3,0($16)
|
||
|
|
beq $18,Lend2 # jump if size was == 2
|
||
|
|
|
||
|
|
.align 3
|
||
|
|
Loop: mulq $2,$19,$3 # $3 = prod_low
|
||
|
|
addq $4,$0,$0 # cy_limb = cy_limb + 'cy'
|
||
|
|
subq $18,1,$18 # size--
|
||
|
|
umulh $2,$19,$4 # $4 = cy_limb
|
||
|
|
ldq $2,16($17) # $2 = s1_limb
|
||
|
|
addq $17,8,$17 # s1_ptr++
|
||
|
|
addq $3,$0,$3 # $3 = cy_limb + prod_low
|
||
|
|
stq $3,8($16)
|
||
|
|
cmpult $3,$0,$0 # $0 = carry from (cy_limb + prod_low)
|
||
|
|
addq $16,8,$16 # res_ptr++
|
||
|
|
bne $18,Loop
|
||
|
|
|
||
|
|
Lend2: mulq $2,$19,$3 # $3 = prod_low
|
||
|
|
addq $4,$0,$0 # cy_limb = cy_limb + 'cy'
|
||
|
|
umulh $2,$19,$4 # $4 = cy_limb
|
||
|
|
addq $3,$0,$3 # $3 = cy_limb + prod_low
|
||
|
|
cmpult $3,$0,$0 # $0 = carry from (cy_limb + prod_low)
|
||
|
|
stq $3,8($16)
|
||
|
|
addq $4,$0,$0 # cy_limb = prod_high + cy
|
||
|
|
ret $31,($26),1
|
||
|
|
Lend1: stq $3,0($16)
|
||
|
|
ret $31,($26),1
|
||
|
|
|
||
|
|
.end __mpn_mul_1
|