openssl/crypto/bn/asm/ppc64-mont-fixed.pl
Martin Schwenke e7370fa016 bn: Fix .size directive
This requires the text address.

Fixes #15923

Signed-off-by: Martin Schwenke <martin@meltin.net>

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/15971)
2021-07-06 10:49:01 +10:00

582 lines
9.7 KiB
Perl
Executable File

#! /usr/bin/env perl
# Copyright 2021 The OpenSSL Project Authors. All Rights Reserved.
#
# Licensed under the Apache License 2.0 (the "License"). You may not use
# this file except in compliance with the License. You can obtain a copy
# in the file LICENSE in the source distribution or at
# https://www.openssl.org/source/license.html
# ====================================================================
# Written by Amitay Isaacs <amitay@ozlabs.org>, Martin Schwenke
# <martin@meltin.net> & Alastair D'Silva <alastair@d-silva.org> for
# the OpenSSL project.
# ====================================================================
#
# Fixed length (n=6), unrolled PPC Montgomery Multiplication
#
# 2021
#
# Although this is a generic implementation for unrolling Montgomery
# Multiplication for arbitrary values of n, this is currently only
# used for n = 6 to improve the performance of ECC p384.
#
# Unrolling allows intermediate results to be stored in registers,
# rather than on the stack, improving performance by ~7% compared to
# the existing PPC assembly code.
#
# The ISA 3.0 implementation uses combination multiply/add
# instructions (maddld, maddhdu) to improve performance by an
# additional ~10% on Power 9.
#
# Finally, saving non-volatile registers into volatile vector
# registers instead of onto the stack saves a little more.
#
# On a Power 9 machine we see an overall improvement of ~18%.
#
use strict;
use warnings;
my ($flavour, $output, $dir, $xlate);
# $output is the last argument if it looks like a file (it has an extension)
# $flavour is the first argument if it doesn't look like a file
$output = $#ARGV >= 0 && $ARGV[$#ARGV] =~ m|\.\w+$| ? pop : undef;
$flavour = $#ARGV >= 0 && $ARGV[0] !~ m|\.| ? shift : undef;
$0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1;
( $xlate="${dir}ppc-xlate.pl" and -f $xlate ) or
( $xlate="${dir}../../perlasm/ppc-xlate.pl" and -f $xlate) or
die "can't locate ppc-xlate.pl";
open STDOUT,"| $^X $xlate $flavour \"$output\""
or die "can't call $xlate: $!";
if ($flavour !~ /64/) {
die "bad flavour ($flavour) - only ppc64 permitted";
}
my $SIZE_T= 8;
# Registers are global so the code is remotely readable
# Parameters for Montgomery multiplication
my $sp = "r1";
my $toc = "r2";
my $rp = "r3";
my $ap = "r4";
my $bp = "r5";
my $np = "r6";
my $n0 = "r7";
my $num = "r8";
my $i = "r9";
my $c0 = "r10";
my $bp0 = "r11";
my $bpi = "r11";
my $bpj = "r11";
my $tj = "r12";
my $apj = "r12";
my $npj = "r12";
my $lo = "r14";
my $c1 = "r14";
# Non-volatile registers used for tp[i]
#
# 12 registers are available but the limit on unrolling is 10,
# since registers from $tp[0] to $tp[$n+1] are used.
my @tp = ("r20" .. "r31");
# volatile VSRs for saving non-volatile GPRs - faster than stack
my @vsrs = ("v32" .. "v46");
package Mont;
sub new($$)
{
my ($class, $n) = @_;
if ($n > 10) {
die "Can't unroll for BN length ${n} (maximum 10)"
}
my $self = {
code => "",
n => $n,
};
bless $self, $class;
return $self;
}
sub add_code($$)
{
my ($self, $c) = @_;
$self->{code} .= $c;
}
sub get_code($)
{
my ($self) = @_;
return $self->{code};
}
sub get_function_name($)
{
my ($self) = @_;
return "bn_mul_mont_fixed_n" . $self->{n};
}
sub get_label($$)
{
my ($self, $l) = @_;
return "L" . $l . "_" . $self->{n};
}
sub get_labels($@)
{
my ($self, @labels) = @_;
my %out = ();
foreach my $l (@labels) {
$out{"$l"} = $self->get_label("$l");
}
return \%out;
}
sub nl($)
{
my ($self) = @_;
$self->add_code("\n");
}
sub copy_result($)
{
my ($self) = @_;
my ($n) = $self->{n};
for (my $j = 0; $j < $n; $j++) {
$self->add_code(<<___);
std $tp[$j],`$j*$SIZE_T`($rp)
___
}
}
sub mul_mont_fixed($)
{
my ($self) = @_;
my ($n) = $self->{n};
my $fname = $self->get_function_name();
my $label = $self->get_labels("outer", "enter", "sub", "copy", "end");
$self->add_code(<<___);
.globl .${fname}
.align 5
.${fname}:
___
$self->save_registers();
$self->add_code(<<___);
ld $n0,0($n0)
ld $bp0,0($bp)
ld $apj,0($ap)
___
$self->mul_c_0($tp[0], $apj, $bp0, $c0);
for (my $j = 1; $j < $n - 1; $j++) {
$self->add_code(<<___);
ld $apj,`$j*$SIZE_T`($ap)
___
$self->mul($tp[$j], $apj, $bp0, $c0);
}
$self->add_code(<<___);
ld $apj,`($n-1)*$SIZE_T`($ap)
___
$self->mul_last($tp[$n-1], $tp[$n], $apj, $bp0, $c0);
$self->add_code(<<___);
li $tp[$n+1],0
___
$self->add_code(<<___);
li $i,0
mtctr $num
b $label->{"enter"}
.align 4
$label->{"outer"}:
ldx $bpi,$bp,$i
ld $apj,0($ap)
___
$self->mul_add_c_0($tp[0], $tp[0], $apj, $bpi, $c0);
for (my $j = 1; $j < $n; $j++) {
$self->add_code(<<___);
ld $apj,`$j*$SIZE_T`($ap)
___
$self->mul_add($tp[$j], $tp[$j], $apj, $bpi, $c0);
}
$self->add_code(<<___);
addc $tp[$n],$tp[$n],$c0
addze $tp[$n+1],$tp[$n+1]
___
$self->add_code(<<___);
.align 4
$label->{"enter"}:
mulld $bpi,$tp[0],$n0
ld $npj,0($np)
___
$self->mul_add_c_0($lo, $tp[0], $bpi, $npj, $c0);
for (my $j = 1; $j < $n; $j++) {
$self->add_code(<<___);
ld $npj,`$j*$SIZE_T`($np)
___
$self->mul_add($tp[$j-1], $tp[$j], $npj, $bpi, $c0);
}
$self->add_code(<<___);
addc $tp[$n-1],$tp[$n],$c0
addze $tp[$n],$tp[$n+1]
addi $i,$i,$SIZE_T
bdnz $label->{"outer"}
and. $tp[$n],$tp[$n],$tp[$n]
bne $label->{"sub"}
cmpld $tp[$n-1],$npj
blt $label->{"copy"}
$label->{"sub"}:
___
#
# Reduction
#
$self->add_code(<<___);
ld $bpj,`0*$SIZE_T`($np)
subfc $c1,$bpj,$tp[0]
std $c1,`0*$SIZE_T`($rp)
___
for (my $j = 1; $j < $n - 1; $j++) {
$self->add_code(<<___);
ld $bpj,`$j*$SIZE_T`($np)
subfe $c1,$bpj,$tp[$j]
std $c1,`$j*$SIZE_T`($rp)
___
}
$self->add_code(<<___);
subfe $c1,$npj,$tp[$n-1]
std $c1,`($n-1)*$SIZE_T`($rp)
___
$self->add_code(<<___);
addme. $tp[$n],$tp[$n]
beq $label->{"end"}
$label->{"copy"}:
___
$self->copy_result();
$self->add_code(<<___);
$label->{"end"}:
___
$self->restore_registers();
$self->add_code(<<___);
li r3,1
blr
.size .${fname},.-.${fname}
___
}
package Mont::GPR;
our @ISA = ('Mont');
sub new($$)
{
my ($class, $n) = @_;
return $class->SUPER::new($n);
}
sub save_registers($)
{
my ($self) = @_;
my $n = $self->{n};
$self->add_code(<<___);
std $lo,-8($sp)
___
for (my $j = 0; $j <= $n+1; $j++) {
$self->{code}.=<<___;
std $tp[$j],-`($j+2)*8`($sp)
___
}
$self->add_code(<<___);
___
}
sub restore_registers($)
{
my ($self) = @_;
my $n = $self->{n};
$self->add_code(<<___);
ld $lo,-8($sp)
___
for (my $j = 0; $j <= $n+1; $j++) {
$self->{code}.=<<___;
ld $tp[$j],-`($j+2)*8`($sp)
___
}
$self->{code} .=<<___;
___
}
# Direct translation of C mul()
sub mul($$$$$)
{
my ($self, $r, $a, $w, $c) = @_;
$self->add_code(<<___);
mulld $lo,$a,$w
addc $r,$lo,$c
mulhdu $c,$a,$w
addze $c,$c
___
}
# Like mul() but $c is ignored as an input - an optimisation to save a
# preliminary instruction that would set input $c to 0
sub mul_c_0($$$$$)
{
my ($self, $r, $a, $w, $c) = @_;
$self->add_code(<<___);
mulld $r,$a,$w
mulhdu $c,$a,$w
___
}
# Like mul() but does not to the final addition of CA into $c - an
# optimisation to save an instruction
sub mul_last($$$$$$)
{
my ($self, $r1, $r2, $a, $w, $c) = @_;
$self->add_code(<<___);
mulld $lo,$a,$w
addc $r1,$lo,$c
mulhdu $c,$a,$w
addze $r2,$c
___
}
# Like C mul_add() but allow $r_out and $r_in to be different
sub mul_add($$$$$$)
{
my ($self, $r_out, $r_in, $a, $w, $c) = @_;
$self->add_code(<<___);
mulld $lo,$a,$w
addc $lo,$lo,$c
mulhdu $c,$a,$w
addze $c,$c
addc $r_out,$r_in,$lo
addze $c,$c
___
}
# Like mul_add() but $c is ignored as an input - an optimisation to save a
# preliminary instruction that would set input $c to 0
sub mul_add_c_0($$$$$$)
{
my ($self, $r_out, $r_in, $a, $w, $c) = @_;
$self->add_code(<<___);
mulld $lo,$a,$w
addc $r_out,$r_in,$lo
mulhdu $c,$a,$w
addze $c,$c
___
}
package Mont::GPR_300;
our @ISA = ('Mont::GPR');
sub new($$)
{
my ($class, $n) = @_;
my $mont = $class->SUPER::new($n);
return $mont;
}
sub get_function_name($)
{
my ($self) = @_;
return "bn_mul_mont_300_fixed_n" . $self->{n};
}
sub get_label($$)
{
my ($self, $l) = @_;
return "L" . $l . "_300_" . $self->{n};
}
# Direct translation of C mul()
sub mul($$$$$)
{
my ($self, $r, $a, $w, $c, $last) = @_;
$self->add_code(<<___);
maddld $r,$a,$w,$c
maddhdu $c,$a,$w,$c
___
}
# Save the last carry as the final entry
sub mul_last($$$$$)
{
my ($self, $r1, $r2, $a, $w, $c) = @_;
$self->add_code(<<___);
maddld $r1,$a,$w,$c
maddhdu $r2,$a,$w,$c
___
}
# Like mul() but $c is ignored as an input - an optimisation to save a
# preliminary instruction that would set input $c to 0
sub mul_c_0($$$$$)
{
my ($self, $r, $a, $w, $c) = @_;
$self->add_code(<<___);
mulld $r,$a,$w
mulhdu $c,$a,$w
___
}
# Like C mul_add() but allow $r_out and $r_in to be different
sub mul_add($$$$$$)
{
my ($self, $r_out, $r_in, $a, $w, $c) = @_;
$self->add_code(<<___);
maddld $lo,$a,$w,$c
maddhdu $c,$a,$w,$c
addc $r_out,$r_in,$lo
addze $c,$c
___
}
# Like mul_add() but $c is ignored as an input - an optimisation to save a
# preliminary instruction that would set input $c to 0
sub mul_add_c_0($$$$$$)
{
my ($self, $r_out, $r_in, $a, $w, $c) = @_;
$self->add_code(<<___);
maddld $lo,$a,$w,$r_in
maddhdu $c,$a,$w,$r_in
___
if ($r_out ne $lo) {
$self->add_code(<<___);
mr $r_out,$lo
___
}
$self->nl();
}
package main;
my $code;
$code.=<<___;
.machine "any"
.text
___
my $mont;
$mont = new Mont::GPR(6);
$mont->mul_mont_fixed();
$code .= $mont->get_code();
$mont = new Mont::GPR_300(6);
$mont->mul_mont_fixed();
$code .= $mont->get_code();
$code =~ s/\`([^\`]*)\`/eval $1/gem;
$code.=<<___;
.asciz "Montgomery Multiplication for PPC by <amitay\@ozlabs.org>, <alastair\@d-silva.org>"
___
print $code;
close STDOUT or die "error closing STDOUT: $!";