dnl PowerPC-32 mpn_addmul_1 -- Multiply a limb vector with a limb and add the
dnl result to a second limb vector.
dnl Copyright 1995, 1997, 1998, 2000-2003, 2005 Free Software Foundation, Inc.
dnl This file is part of the GNU MP Library.
dnl
dnl The GNU MP Library is free software; you can redistribute it and/or modify
dnl it under the terms of either:
dnl
dnl * the GNU Lesser General Public License as published by the Free
dnl Software Foundation; either version 3 of the License, or (at your
dnl option) any later version.
dnl
dnl or
dnl
dnl * the GNU General Public License as published by the Free Software
dnl Foundation; either version 2 of the License, or (at your option) any
dnl later version.
dnl
dnl or both in parallel, as here.
dnl
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 General Public License
dnl for more details.
dnl
dnl You should have received copies of the GNU General Public License and the
dnl GNU Lesser General Public License along with the GNU MP Library. If not,
dnl see https://www.gnu.org/licenses/.
include(`../config.m4')
C cycles/limb
C 603e: ?
C 604e: 6.75
C 75x (G3): 8.7-14.3
C 7400,7410 (G4): 8.7-14.3
C 744x,745x (G4+): 9.5
C power4/ppc970: 6.25
C power5: 6.25
C INPUT PARAMETERS
C rp r3
C up r4
C n r5
C vl r6
C This is optimized for the PPC604. It has not been tuned for other
C PowerPC processors.
C
C Loop Analysis for the 604:
C 12 mem insn
C 8 serializing insn
C 8 int multiply
C 25 int reg write
C 9 int ops (8 of which serialize)
C
C The multiply insns need 16 cycles/4limb.
C The integer register writes will need 13 cycles/4limb.
C All-in-all, it should be possible to get to 4 or 5 cycles/limb on PPC604,
C but that will require some clever FPNOPS and BNOPS for exact
C issue control.
ASM_START()
PROLOGUE(mpn_addmul_1)
cmpwi cr0,r5,9 C more than 9 limbs?
bgt cr0,L(big) C branch if more than 9 limbs
mtctr r5
lwz r0,0(r4)
mullw r7,r0,r6
mulhwu r10,r0,r6
lwz r9,0(r3)
addc r8,r7,r9
addi r3,r3,-4
bdz L(end)
L(loop):
lwzu r0,4(r4)
stwu r8,4(r3)
mullw r8,r0,r6
adde r7,r8,r10
mulhwu r10,r0,r6
lwz r9,4(r3)
addze r10,r10
addc r8,r7,r9
bdnz L(loop)
L(end): stw r8,4(r3)
addze r3,r10
blr
L(big): stwu r1,-16(r1)
addi r5,r5,-1
stw r30,8(r1)
srwi r0,r5,2
stw r31,12(r1)
mtctr r0
lwz r7,0(r4)
mullw r8,r7,r6
mulhwu r0,r7,r6
lwz r7,0(r3)
addc r8,r8,r7
stw r8,0(r3)
L(loopU):
lwz r7,4(r4)
lwz r12,8(r4)
lwz r30,12(r4)
lwzu r31,16(r4)
mullw r8,r7,r6
mullw r9,r12,r6
mullw r10,r30,r6
mullw r11,r31,r6
adde r8,r8,r0 C add cy_limb
mulhwu r0,r7,r6
lwz r7,4(r3)
adde r9,r9,r0
mulhwu r0,r12,r6
lwz r12,8(r3)
adde r10,r10,r0
mulhwu r0,r30,r6
lwz r30,12(r3)
adde r11,r11,r0
mulhwu r0,r31,r6
lwz r31,16(r3)
addze r0,r0 C new cy_limb
addc r8,r8,r7
stw r8,4(r3)
adde r9,r9,r12
stw r9,8(r3)
adde r10,r10,r30
stw r10,12(r3)
adde r11,r11,r31
stwu r11,16(r3)
bdnz L(loopU)
andi. r31,r5,3
mtctr r31
beq cr0,L(endx)
L(loopE):
lwzu r7,4(r4)
mullw r8,r7,r6
adde r8,r8,r0 C add cy_limb
mulhwu r0,r7,r6
lwz r7,4(r3)
addze r0,r0 C new cy_limb
addc r8,r8,r7
stwu r8,4(r3)
bdnz L(loopE)
L(endx):
addze r3,r0
lwz r30,8(r1)
lwz r31,12(r1)
addi r1,r1,16
blr
EPILOGUE(mpn_addmul_1)