dnl SPARC v9 32-bit mpn_mul_1 -- Multiply a limb vector with a limb and store
dnl the result in a second limb vector.
dnl Copyright 1998, 2000, 2001, 2003 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 Algorithm: We use two floating-point multiplies per limb product, with the
C invariant v operand split into two 16-bit pieces, and the u operand split
C into 32-bit pieces. We convert the two 48-bit products and transfer them to
C the integer unit.
C cycles/limb
C UltraSPARC 1&2: 6.5
C UltraSPARC 3: ?
C Possible optimizations:
C 1. Combine 32-bit memory operations into 64-bit operations. Since we're
C memory bandwidth limited, this could save 1.5 cycles/limb.
C 2. Unroll the inner loop. Since we already use alternate temporary areas,
C it is very straightforward to unroll, using an exit branch midways.
C Unrolling would allow deeper scheduling which could improve speed for L2
C cache case.
C 3. For mpn_mul_1: Use more alternating temp areas. The std'es and ldx'es
C aren't sufficiently apart-scheduled with just two temp areas.
C 4. Specialize for particular v values. If its upper 16 bits are zero, we
C could save many operations.
C INPUT PARAMETERS
C rp i0
C up i1
C n i2
C v i3
define(`FSIZE',224)
ASM_START()
PROLOGUE(mpn_mul_1)
add %sp, -FSIZE, %sp
sethi %hi(0xffff), %g1
srl %o3, 16, %g2
or %g1, %lo(0xffff), %g1
and %o3, %g1, %g1
stx %g1, [%sp+104]
stx %g2, [%sp+112]
ldd [%sp+104], %f6
ldd [%sp+112], %f8
fxtod %f6, %f6
fxtod %f8, %f8
ld [%sp+104], %f10 C zero f10
mov 0, %g3 C cy = 0
define(`fanop', `fitod %f18, %f0') C A quasi nop running in the FA pipe
add %sp, 160, %o5 C point in scratch area
and %o5, -32, %o5 C align at 0 (mod 32) in scratch area
subcc %o2, 1, %o2
ld [%o1], %f11 C read up[i]
add %o1, 4, %o1 C up++
bne,pt %icc, .L_two_or_more
fxtod %f10, %f2
fmuld %f2, %f8, %f16
fmuld %f2, %f6, %f4
fdtox %f16, %f14
fdtox %f4, %f12
std %f14, [%o5+16]
std %f12, [%o5+24]
ldx [%o5+16], %g2 C p16
ldx [%o5+24], %g1 C p0
b .L1
add %o0, -16, %o0
.align 16
.L_two_or_more:
subcc %o2, 1, %o2
ld [%o1], %f11 C read up[i]
fmuld %f2, %f8, %f16
fmuld %f2, %f6, %f4
add %o1, 4, %o1 C up++
bne,pt %icc, .L_three_or_more
fxtod %f10, %f2
fdtox %f16, %f14
fdtox %f4, %f12
std %f14, [%o5+16]
fmuld %f2, %f8, %f16
std %f12, [%o5+24]
fmuld %f2, %f6, %f4
fdtox %f16, %f14
fdtox %f4, %f12
std %f14, [%o5+0]
std %f12, [%o5+8]
ldx [%o5+16], %g2 C p16
ldx [%o5+24], %g1 C p0
b .L2
add %o0, -12, %o0
.align 16
.L_three_or_more:
subcc %o2, 1, %o2
ld [%o1], %f11 C read up[i]
fdtox %f16, %f14
fdtox %f4, %f12
std %f14, [%o5+16]
fmuld %f2, %f8, %f16
std %f12, [%o5+24]
fmuld %f2, %f6, %f4
add %o1, 4, %o1 C up++
bne,pt %icc, .L_four_or_more
fxtod %f10, %f2
fdtox %f16, %f14
fdtox %f4, %f12
std %f14, [%o5+0]
fmuld %f2, %f8, %f16
std %f12, [%o5+8]
fmuld %f2, %f6, %f4
fdtox %f16, %f14
ldx [%o5+16], %g2 C p16
fdtox %f4, %f12
ldx [%o5+24], %g1 C p0
std %f14, [%o5+16]
std %f12, [%o5+24]
b .L3
add %o0, -8, %o0
.align 16
.L_four_or_more:
subcc %o2, 1, %o2
ld [%o1], %f11 C read up[i]
fdtox %f16, %f14
fdtox %f4, %f12
std %f14, [%o5+0]
fmuld %f2, %f8, %f16
std %f12, [%o5+8]
fmuld %f2, %f6, %f4
add %o1, 4, %o1 C up++
bne,pt %icc, .L_five_or_more
fxtod %f10, %f2
fdtox %f16, %f14
ldx [%o5+16], %g2 C p16
fdtox %f4, %f12
ldx [%o5+24], %g1 C p0
std %f14, [%o5+16]
fmuld %f2, %f8, %f16
std %f12, [%o5+24]
fmuld %f2, %f6, %f4
add %o1, 4, %o1 C up++
b .L4
add %o0, -4, %o0
.align 16
.L_five_or_more:
subcc %o2, 1, %o2
ld [%o1], %f11 C read up[i]
fdtox %f16, %f14
ldx [%o5+16], %g2 C p16
fdtox %f4, %f12
ldx [%o5+24], %g1 C p0
std %f14, [%o5+16]
fmuld %f2, %f8, %f16
std %f12, [%o5+24]
fmuld %f2, %f6, %f4
add %o1, 4, %o1 C up++
bne,pt %icc, .Loop
fxtod %f10, %f2
b,a .L5
C BEGIN MAIN LOOP
.align 16
C -- 0
.Loop: nop
subcc %o2, 1, %o2
ld [%o1], %f11 C read up[i]
fdtox %f16, %f14
C -- 1
sllx %g2, 16, %g4 C (p16 << 16)
add %o0, 4, %o0 C rp++
ldx [%o5+0], %g2 C p16
fdtox %f4, %f12
C -- 2
nop
add %g1, %g4, %g4 C p = p0 + (p16 << 16)
ldx [%o5+8], %g1 C p0
fanop
C -- 3
nop
add %g3, %g4, %g4 C p += cy
std %f14, [%o5+0]
fmuld %f2, %f8, %f16
C -- 4
srlx %g4, 32, %g3 C new cy
add %o1, 4, %o1 C up++
std %f12, [%o5+8]
fmuld %f2, %f6, %f4
C -- 5
xor %o5, 16, %o5 C alternate scratch variables
stw %g4, [%o0-4]
bne,pt %icc, .Loop
fxtod %f10, %f2
C END MAIN LOOP
.L5: fdtox %f16, %f14
sllx %g2, 16, %g4 C (p16 << 16)
ldx [%o5+0], %g2 C p16
fdtox %f4, %f12
add %g1, %g4, %g4 C p = p0 + (p16 << 16)
ldx [%o5+8], %g1 C p0
add %g4, %g3, %g4 C p += cy
std %f14, [%o5+0]
fmuld %f2, %f8, %f16
std %f12, [%o5+8]
fmuld %f2, %f6, %f4
xor %o5, 16, %o5
stw %g4, [%o0+0]
srlx %g4, 32, %g3 C new cy
.L4: fdtox %f16, %f14
sllx %g2, 16, %g4 C (p16 << 16)
ldx [%o5+0], %g2 C p16
fdtox %f4, %f12
add %g1, %g4, %g4 C p = p0 + (p16 << 16)
ldx [%o5+8], %g1 C p0
add %g3, %g4, %g4 C p += cy
std %f14, [%o5+0]
std %f12, [%o5+8]
xor %o5, 16, %o5
stw %g4, [%o0+4]
srlx %g4, 32, %g3 C new cy
.L3: sllx %g2, 16, %g4 C (p16 << 16)
ldx [%o5+0], %g2 C p16
add %g1, %g4, %g4 C p = p0 + (p16 << 16)
ldx [%o5+8], %g1 C p0
add %g3, %g4, %g4 C p += cy
xor %o5, 16, %o5
stw %g4, [%o0+8]
srlx %g4, 32, %g3 C new cy
.L2: sllx %g2, 16, %g4 C (p16 << 16)
ldx [%o5+0], %g2 C p16
add %g1, %g4, %g4 C p = p0 + (p16 << 16)
ldx [%o5+8], %g1 C p0
add %g3, %g4, %g4 C p += cy
stw %g4, [%o0+12]
srlx %g4, 32, %g3 C new cy
.L1: sllx %g2, 16, %g4 C (p16 << 16)
add %g1, %g4, %g4 C p = p0 + (p16 << 16)
add %g3, %g4, %g4 C p += cy
stw %g4, [%o0+16]
srlx %g4, 32, %g3 C new cy
mov %g3, %o0
retl
sub %sp, -FSIZE, %sp
EPILOGUE(mpn_mul_1)