openssl/crypto/modes/asm/ghash-x86.pl

1405 lines
41 KiB
Raku
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

#! /usr/bin/env perl
# Copyright 2010-2020 The OpenSSL Project Authors. All Rights Reserved.
#
# Licensed under the OpenSSL license (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 Andy Polyakov <appro@openssl.org> for the OpenSSL
# project. The module is, however, dual licensed under OpenSSL and
# CRYPTOGAMS licenses depending on where you obtain it. For further
# details see http://www.openssl.org/~appro/cryptogams/.
# ====================================================================
#
# March, May, June 2010
#
# The module implements "4-bit" GCM GHASH function and underlying
# single multiplication operation in GF(2^128). "4-bit" means that it
# uses 256 bytes per-key table [+64/128 bytes fixed table]. It has two
# code paths: vanilla x86 and vanilla SSE. Former will be executed on
# 486 and Pentium, latter on all others. SSE GHASH features so called
# "528B" variant of "4-bit" method utilizing additional 256+16 bytes
# of per-key storage [+512 bytes shared table]. Performance results
# are for streamed GHASH subroutine and are expressed in cycles per
# processed byte, less is better:
#
# gcc 2.95.3(*) SSE assembler x86 assembler
#
# Pentium 105/111(**) - 50
# PIII 68 /75 12.2 24
# P4 125/125 17.8 84(***)
# Opteron 66 /70 10.1 30
# Core2 54 /67 8.4 18
# Atom 105/105 16.8 53
# VIA Nano 69 /71 13.0 27
#
# (*) gcc 3.4.x was observed to generate few percent slower code,
# which is one of reasons why 2.95.3 results were chosen,
# another reason is lack of 3.4.x results for older CPUs;
# comparison with SSE results is not completely fair, because C
# results are for vanilla "256B" implementation, while
# assembler results are for "528B";-)
# (**) second number is result for code compiled with -fPIC flag,
# which is actually more relevant, because assembler code is
# position-independent;
# (***) see comment in non-MMX routine for further details;
#
# To summarize, it's >2-5 times faster than gcc-generated code. To
# anchor it to something else SHA1 assembler processes one byte in
# ~7 cycles on contemporary x86 cores. As for choice of MMX/SSE
# in particular, see comment at the end of the file...
# May 2010
#
# Add PCLMULQDQ version performing at 2.10 cycles per processed byte.
# The question is how close is it to theoretical limit? The pclmulqdq
# instruction latency appears to be 14 cycles and there can't be more
# than 2 of them executing at any given time. This means that single
# Karatsuba multiplication would take 28 cycles *plus* few cycles for
# pre- and post-processing. Then multiplication has to be followed by
# modulo-reduction. Given that aggregated reduction method [see
# "Carry-less Multiplication and Its Usage for Computing the GCM Mode"
# white paper by Intel] allows you to perform reduction only once in
# a while we can assume that asymptotic performance can be estimated
# as (28+Tmod/Naggr)/16, where Tmod is time to perform reduction
# and Naggr is the aggregation factor.
#
# Before we proceed to this implementation let's have closer look at
# the best-performing code suggested by Intel in their white paper.
# By tracing inter-register dependencies Tmod is estimated as ~19
# cycles and Naggr chosen by Intel is 4, resulting in 2.05 cycles per
# processed byte. As implied, this is quite optimistic estimate,
# because it does not account for Karatsuba pre- and post-processing,
# which for a single multiplication is ~5 cycles. Unfortunately Intel
# does not provide performance data for GHASH alone. But benchmarking
# AES_GCM_encrypt ripped out of Fig. 15 of the white paper with aadt
# alone resulted in 2.46 cycles per byte of out 16KB buffer. Note that
# the result accounts even for pre-computing of degrees of the hash
# key H, but its portion is negligible at 16KB buffer size.
#
# Moving on to the implementation in question. Tmod is estimated as
# ~13 cycles and Naggr is 2, giving asymptotic performance of ...
# 2.16. How is it possible that measured performance is better than
# optimistic theoretical estimate? There is one thing Intel failed
# to recognize. By serializing GHASH with CTR in same subroutine
# former's performance is really limited to above (Tmul + Tmod/Naggr)
# equation. But if GHASH procedure is detached, the modulo-reduction
# can be interleaved with Naggr-1 multiplications at instruction level
# and under ideal conditions even disappear from the equation. So that
# optimistic theoretical estimate for this implementation is ...
# 28/16=1.75, and not 2.16. Well, it's probably way too optimistic,
# at least for such small Naggr. I'd argue that (28+Tproc/Naggr),
# where Tproc is time required for Karatsuba pre- and post-processing,
# is more realistic estimate. In this case it gives ... 1.91 cycles.
# Or in other words, depending on how well we can interleave reduction
# and one of the two multiplications the performance should be between
# 1.91 and 2.16. As already mentioned, this implementation processes
# one byte out of 8KB buffer in 2.10 cycles, while x86_64 counterpart
# - in 2.02. x86_64 performance is better, because larger register
# bank allows to interleave reduction and multiplication better.
#
# Does it make sense to increase Naggr? To start with it's virtually
# impossible in 32-bit mode, because of limited register bank
# capacity. Otherwise improvement has to be weighed against slower
# setup, as well as code size and complexity increase. As even
# optimistic estimate doesn't promise 30% performance improvement,
# there are currently no plans to increase Naggr.
#
# Special thanks to David Woodhouse for providing access to a
# Westmere-based system on behalf of Intel Open Source Technology Centre.
# January 2010
#
# Tweaked to optimize transitions between integer and FP operations
# on same XMM register, PCLMULQDQ subroutine was measured to process
# one byte in 2.07 cycles on Sandy Bridge, and in 2.12 - on Westmere.
# The minor regression on Westmere is outweighed by ~15% improvement
# on Sandy Bridge. Strangely enough attempt to modify 64-bit code in
# similar manner resulted in almost 20% degradation on Sandy Bridge,
# where original 64-bit code processes one byte in 1.95 cycles.
#####################################################################
# For reference, AMD Bulldozer processes one byte in 1.98 cycles in
# 32-bit mode and 1.89 in 64-bit.
# February 2013
#
# Overhaul: aggregate Karatsuba post-processing, improve ILP in
# reduction_alg9. Resulting performance is 1.96 cycles per byte on
# Westmere, 1.95 - on Sandy/Ivy Bridge, 1.76 - on Bulldozer.
$0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1;
push(@INC,"${dir}","${dir}../../perlasm");
require "x86asm.pl";
$output=pop;
open STDOUT,">$output";
&asm_init($ARGV[0],$x86only = $ARGV[$#ARGV] eq "386");
$sse2=0;
for (@ARGV) { $sse2=1 if (/-DOPENSSL_IA32_SSE2/); }
($Zhh,$Zhl,$Zlh,$Zll) = ("ebp","edx","ecx","ebx");
$inp = "edi";
$Htbl = "esi";
$unroll = 0; # Affects x86 loop. Folded loop performs ~7% worse
# than unrolled, which has to be weighted against
# 2.5x x86-specific code size reduction.
sub x86_loop {
my $off = shift;
my $rem = "eax";
&mov ($Zhh,&DWP(4,$Htbl,$Zll));
&mov ($Zhl,&DWP(0,$Htbl,$Zll));
&mov ($Zlh,&DWP(12,$Htbl,$Zll));
&mov ($Zll,&DWP(8,$Htbl,$Zll));
&xor ($rem,$rem); # avoid partial register stalls on PIII
# shrd practically kills P4, 2.5x deterioration, but P4 has
# MMX code-path to execute. shrd runs tad faster [than twice
# the shifts, move's and or's] on pre-MMX Pentium (as well as
# PIII and Core2), *but* minimizes code size, spares register
# and thus allows to fold the loop...
if (!$unroll) {
my $cnt = $inp;
&mov ($cnt,15);
&jmp (&label("x86_loop"));
&set_label("x86_loop",16);
for($i=1;$i<=2;$i++) {
&mov (&LB($rem),&LB($Zll));
&shrd ($Zll,$Zlh,4);
&and (&LB($rem),0xf);
&shrd ($Zlh,$Zhl,4);
&shrd ($Zhl,$Zhh,4);
&shr ($Zhh,4);
&xor ($Zhh,&DWP($off+16,"esp",$rem,4));
&mov (&LB($rem),&BP($off,"esp",$cnt));
if ($i&1) {
&and (&LB($rem),0xf0);
} else {
&shl (&LB($rem),4);
}
&xor ($Zll,&DWP(8,$Htbl,$rem));
&xor ($Zlh,&DWP(12,$Htbl,$rem));
&xor ($Zhl,&DWP(0,$Htbl,$rem));
&xor ($Zhh,&DWP(4,$Htbl,$rem));
if ($i&1) {
&dec ($cnt);
&js (&label("x86_break"));
} else {
&jmp (&label("x86_loop"));
}
}
&set_label("x86_break",16);
} else {
for($i=1;$i<32;$i++) {
&comment($i);
&mov (&LB($rem),&LB($Zll));
&shrd ($Zll,$Zlh,4);
&and (&LB($rem),0xf);
&shrd ($Zlh,$Zhl,4);
&shrd ($Zhl,$Zhh,4);
&shr ($Zhh,4);
&xor ($Zhh,&DWP($off+16,"esp",$rem,4));
if ($i&1) {
&mov (&LB($rem),&BP($off+15-($i>>1),"esp"));
&and (&LB($rem),0xf0);
} else {
&mov (&LB($rem),&BP($off+15-($i>>1),"esp"));
&shl (&LB($rem),4);
}
&xor ($Zll,&DWP(8,$Htbl,$rem));
&xor ($Zlh,&DWP(12,$Htbl,$rem));
&xor ($Zhl,&DWP(0,$Htbl,$rem));
&xor ($Zhh,&DWP(4,$Htbl,$rem));
}
}
&bswap ($Zll);
&bswap ($Zlh);
&bswap ($Zhl);
if (!$x86only) {
&bswap ($Zhh);
} else {
&mov ("eax",$Zhh);
&bswap ("eax");
&mov ($Zhh,"eax");
}
}
if ($unroll) {
&function_begin_B("_x86_gmult_4bit_inner");
&x86_loop(4);
&ret ();
&function_end_B("_x86_gmult_4bit_inner");
}
sub deposit_rem_4bit {
my $bias = shift;
&mov (&DWP($bias+0, "esp"),0x0000<<16);
&mov (&DWP($bias+4, "esp"),0x1C20<<16);
&mov (&DWP($bias+8, "esp"),0x3840<<16);
&mov (&DWP($bias+12,"esp"),0x2460<<16);
&mov (&DWP($bias+16,"esp"),0x7080<<16);
&mov (&DWP($bias+20,"esp"),0x6CA0<<16);
&mov (&DWP($bias+24,"esp"),0x48C0<<16);
&mov (&DWP($bias+28,"esp"),0x54E0<<16);
&mov (&DWP($bias+32,"esp"),0xE100<<16);
&mov (&DWP($bias+36,"esp"),0xFD20<<16);
&mov (&DWP($bias+40,"esp"),0xD940<<16);
&mov (&DWP($bias+44,"esp"),0xC560<<16);
&mov (&DWP($bias+48,"esp"),0x9180<<16);
&mov (&DWP($bias+52,"esp"),0x8DA0<<16);
&mov (&DWP($bias+56,"esp"),0xA9C0<<16);
&mov (&DWP($bias+60,"esp"),0xB5E0<<16);
}
$suffix = $x86only ? "" : "_x86";
&function_begin("gcm_gmult_4bit".$suffix);
&stack_push(16+4+1); # +1 for stack alignment
&mov ($inp,&wparam(0)); # load Xi
&mov ($Htbl,&wparam(1)); # load Htable
&mov ($Zhh,&DWP(0,$inp)); # load Xi[16]
&mov ($Zhl,&DWP(4,$inp));
&mov ($Zlh,&DWP(8,$inp));
&mov ($Zll,&DWP(12,$inp));
&deposit_rem_4bit(16);
&mov (&DWP(0,"esp"),$Zhh); # copy Xi[16] on stack
&mov (&DWP(4,"esp"),$Zhl);
&mov (&DWP(8,"esp"),$Zlh);
&mov (&DWP(12,"esp"),$Zll);
&shr ($Zll,20);
&and ($Zll,0xf0);
if ($unroll) {
&call ("_x86_gmult_4bit_inner");
} else {
&x86_loop(0);
&mov ($inp,&wparam(0));
}
&mov (&DWP(12,$inp),$Zll);
&mov (&DWP(8,$inp),$Zlh);
&mov (&DWP(4,$inp),$Zhl);
&mov (&DWP(0,$inp),$Zhh);
&stack_pop(16+4+1);
&function_end("gcm_gmult_4bit".$suffix);
&function_begin("gcm_ghash_4bit".$suffix);
&stack_push(16+4+1); # +1 for 64-bit alignment
&mov ($Zll,&wparam(0)); # load Xi
&mov ($Htbl,&wparam(1)); # load Htable
&mov ($inp,&wparam(2)); # load in
&mov ("ecx",&wparam(3)); # load len
&add ("ecx",$inp);
&mov (&wparam(3),"ecx");
&mov ($Zhh,&DWP(0,$Zll)); # load Xi[16]
&mov ($Zhl,&DWP(4,$Zll));
&mov ($Zlh,&DWP(8,$Zll));
&mov ($Zll,&DWP(12,$Zll));
&deposit_rem_4bit(16);
&set_label("x86_outer_loop",16);
&xor ($Zll,&DWP(12,$inp)); # xor with input
&xor ($Zlh,&DWP(8,$inp));
&xor ($Zhl,&DWP(4,$inp));
&xor ($Zhh,&DWP(0,$inp));
&mov (&DWP(12,"esp"),$Zll); # dump it on stack
&mov (&DWP(8,"esp"),$Zlh);
&mov (&DWP(4,"esp"),$Zhl);
&mov (&DWP(0,"esp"),$Zhh);
&shr ($Zll,20);
&and ($Zll,0xf0);
if ($unroll) {
&call ("_x86_gmult_4bit_inner");
} else {
&x86_loop(0);
&mov ($inp,&wparam(2));
}
&lea ($inp,&DWP(16,$inp));
&cmp ($inp,&wparam(3));
&mov (&wparam(2),$inp) if (!$unroll);
&jb (&label("x86_outer_loop"));
&mov ($inp,&wparam(0)); # load Xi
&mov (&DWP(12,$inp),$Zll);
&mov (&DWP(8,$inp),$Zlh);
&mov (&DWP(4,$inp),$Zhl);
&mov (&DWP(0,$inp),$Zhh);
&stack_pop(16+4+1);
&function_end("gcm_ghash_4bit".$suffix);
if (!$x86only) {{{
&static_label("rem_4bit");
if (!$sse2) {{ # pure-MMX "May" version...
$S=12; # shift factor for rem_4bit
&function_begin_B("_mmx_gmult_4bit_inner");
# MMX version performs 3.5 times better on P4 (see comment in non-MMX
# routine for further details), 100% better on Opteron, ~70% better
# on Core2 and PIII... In other words effort is considered to be well
# spent... Since initial release the loop was unrolled in order to
# "liberate" register previously used as loop counter. Instead it's
# used to optimize critical path in 'Z.hi ^= rem_4bit[Z.lo&0xf]'.
# The path involves move of Z.lo from MMX to integer register,
# effective address calculation and finally merge of value to Z.hi.
# Reference to rem_4bit is scheduled so late that I had to >>4
# rem_4bit elements. This resulted in 20-45% procent improvement
# on contemporary µ-archs.
{
my $cnt;
my $rem_4bit = "eax";
my @rem = ($Zhh,$Zll);
my $nhi = $Zhl;
my $nlo = $Zlh;
my ($Zlo,$Zhi) = ("mm0","mm1");
my $tmp = "mm2";
&xor ($nlo,$nlo); # avoid partial register stalls on PIII
&mov ($nhi,$Zll);
&mov (&LB($nlo),&LB($nhi));
&shl (&LB($nlo),4);
&and ($nhi,0xf0);
&movq ($Zlo,&QWP(8,$Htbl,$nlo));
&movq ($Zhi,&QWP(0,$Htbl,$nlo));
&movd ($rem[0],$Zlo);
for ($cnt=28;$cnt>=-2;$cnt--) {
my $odd = $cnt&1;
my $nix = $odd ? $nlo : $nhi;
&shl (&LB($nlo),4) if ($odd);
&psrlq ($Zlo,4);
&movq ($tmp,$Zhi);
&psrlq ($Zhi,4);
&pxor ($Zlo,&QWP(8,$Htbl,$nix));
&mov (&LB($nlo),&BP($cnt/2,$inp)) if (!$odd && $cnt>=0);
&psllq ($tmp,60);
&and ($nhi,0xf0) if ($odd);
&pxor ($Zhi,&QWP(0,$rem_4bit,$rem[1],8)) if ($cnt<28);
&and ($rem[0],0xf);
&pxor ($Zhi,&QWP(0,$Htbl,$nix));
&mov ($nhi,$nlo) if (!$odd && $cnt>=0);
&movd ($rem[1],$Zlo);
&pxor ($Zlo,$tmp);
push (@rem,shift(@rem)); # "rotate" registers
}
&mov ($inp,&DWP(4,$rem_4bit,$rem[1],8)); # last rem_4bit[rem]
&psrlq ($Zlo,32); # lower part of Zlo is already there
&movd ($Zhl,$Zhi);
&psrlq ($Zhi,32);
&movd ($Zlh,$Zlo);
&movd ($Zhh,$Zhi);
&shl ($inp,4); # compensate for rem_4bit[i] being >>4
&bswap ($Zll);
&bswap ($Zhl);
&bswap ($Zlh);
&xor ($Zhh,$inp);
&bswap ($Zhh);
&ret ();
}
&function_end_B("_mmx_gmult_4bit_inner");
&function_begin("gcm_gmult_4bit_mmx");
&mov ($inp,&wparam(0)); # load Xi
&mov ($Htbl,&wparam(1)); # load Htable
&call (&label("pic_point"));
&set_label("pic_point");
&blindpop("eax");
&lea ("eax",&DWP(&label("rem_4bit")."-".&label("pic_point"),"eax"));
&movz ($Zll,&BP(15,$inp));
&call ("_mmx_gmult_4bit_inner");
&mov ($inp,&wparam(0)); # load Xi
&emms ();
&mov (&DWP(12,$inp),$Zll);
&mov (&DWP(4,$inp),$Zhl);
&mov (&DWP(8,$inp),$Zlh);
&mov (&DWP(0,$inp),$Zhh);
&function_end("gcm_gmult_4bit_mmx");
# Streamed version performs 20% better on P4, 7% on Opteron,
# 10% on Core2 and PIII...
&function_begin("gcm_ghash_4bit_mmx");
&mov ($Zhh,&wparam(0)); # load Xi
&mov ($Htbl,&wparam(1)); # load Htable
&mov ($inp,&wparam(2)); # load in
&mov ($Zlh,&wparam(3)); # load len
&call (&label("pic_point"));
&set_label("pic_point");
&blindpop("eax");
&lea ("eax",&DWP(&label("rem_4bit")."-".&label("pic_point"),"eax"));
&add ($Zlh,$inp);
&mov (&wparam(3),$Zlh); # len to point at the end of input
&stack_push(4+1); # +1 for stack alignment
&mov ($Zll,&DWP(12,$Zhh)); # load Xi[16]
&mov ($Zhl,&DWP(4,$Zhh));
&mov ($Zlh,&DWP(8,$Zhh));
&mov ($Zhh,&DWP(0,$Zhh));
&jmp (&label("mmx_outer_loop"));
&set_label("mmx_outer_loop",16);
&xor ($Zll,&DWP(12,$inp));
&xor ($Zhl,&DWP(4,$inp));
&xor ($Zlh,&DWP(8,$inp));
&xor ($Zhh,&DWP(0,$inp));
&mov (&wparam(2),$inp);
&mov (&DWP(12,"esp"),$Zll);
&mov (&DWP(4,"esp"),$Zhl);
&mov (&DWP(8,"esp"),$Zlh);
&mov (&DWP(0,"esp"),$Zhh);
&mov ($inp,"esp");
&shr ($Zll,24);
&call ("_mmx_gmult_4bit_inner");
&mov ($inp,&wparam(2));
&lea ($inp,&DWP(16,$inp));
&cmp ($inp,&wparam(3));
&jb (&label("mmx_outer_loop"));
&mov ($inp,&wparam(0)); # load Xi
&emms ();
&mov (&DWP(12,$inp),$Zll);
&mov (&DWP(4,$inp),$Zhl);
&mov (&DWP(8,$inp),$Zlh);
&mov (&DWP(0,$inp),$Zhh);
&stack_pop(4+1);
&function_end("gcm_ghash_4bit_mmx");
}} else {{ # "June" MMX version...
# ... has slower "April" gcm_gmult_4bit_mmx with folded
# loop. This is done to conserve code size...
$S=16; # shift factor for rem_4bit
sub mmx_loop() {
# MMX version performs 2.8 times better on P4 (see comment in non-MMX
# routine for further details), 40% better on Opteron and Core2, 50%
# better on PIII... In other words effort is considered to be well
# spent...
my $inp = shift;
my $rem_4bit = shift;
my $cnt = $Zhh;
my $nhi = $Zhl;
my $nlo = $Zlh;
my $rem = $Zll;
my ($Zlo,$Zhi) = ("mm0","mm1");
my $tmp = "mm2";
&xor ($nlo,$nlo); # avoid partial register stalls on PIII
&mov ($nhi,$Zll);
&mov (&LB($nlo),&LB($nhi));
&mov ($cnt,14);
&shl (&LB($nlo),4);
&and ($nhi,0xf0);
&movq ($Zlo,&QWP(8,$Htbl,$nlo));
&movq ($Zhi,&QWP(0,$Htbl,$nlo));
&movd ($rem,$Zlo);
&jmp (&label("mmx_loop"));
&set_label("mmx_loop",16);
&psrlq ($Zlo,4);
&and ($rem,0xf);
&movq ($tmp,$Zhi);
&psrlq ($Zhi,4);
&pxor ($Zlo,&QWP(8,$Htbl,$nhi));
&mov (&LB($nlo),&BP(0,$inp,$cnt));
&psllq ($tmp,60);
&pxor ($Zhi,&QWP(0,$rem_4bit,$rem,8));
&dec ($cnt);
&movd ($rem,$Zlo);
&pxor ($Zhi,&QWP(0,$Htbl,$nhi));
&mov ($nhi,$nlo);
&pxor ($Zlo,$tmp);
&js (&label("mmx_break"));
&shl (&LB($nlo),4);
&and ($rem,0xf);
&psrlq ($Zlo,4);
&and ($nhi,0xf0);
&movq ($tmp,$Zhi);
&psrlq ($Zhi,4);
&pxor ($Zlo,&QWP(8,$Htbl,$nlo));
&psllq ($tmp,60);
&pxor ($Zhi,&QWP(0,$rem_4bit,$rem,8));
&movd ($rem,$Zlo);
&pxor ($Zhi,&QWP(0,$Htbl,$nlo));
&pxor ($Zlo,$tmp);
&jmp (&label("mmx_loop"));
&set_label("mmx_break",16);
&shl (&LB($nlo),4);
&and ($rem,0xf);
&psrlq ($Zlo,4);
&and ($nhi,0xf0);
&movq ($tmp,$Zhi);
&psrlq ($Zhi,4);
&pxor ($Zlo,&QWP(8,$Htbl,$nlo));
&psllq ($tmp,60);
&pxor ($Zhi,&QWP(0,$rem_4bit,$rem,8));
&movd ($rem,$Zlo);
&pxor ($Zhi,&QWP(0,$Htbl,$nlo));
&pxor ($Zlo,$tmp);
&psrlq ($Zlo,4);
&and ($rem,0xf);
&movq ($tmp,$Zhi);
&psrlq ($Zhi,4);
&pxor ($Zlo,&QWP(8,$Htbl,$nhi));
&psllq ($tmp,60);
&pxor ($Zhi,&QWP(0,$rem_4bit,$rem,8));
&movd ($rem,$Zlo);
&pxor ($Zhi,&QWP(0,$Htbl,$nhi));
&pxor ($Zlo,$tmp);
&psrlq ($Zlo,32); # lower part of Zlo is already there
&movd ($Zhl,$Zhi);
&psrlq ($Zhi,32);
&movd ($Zlh,$Zlo);
&movd ($Zhh,$Zhi);
&bswap ($Zll);
&bswap ($Zhl);
&bswap ($Zlh);
&bswap ($Zhh);
}
&function_begin("gcm_gmult_4bit_mmx");
&mov ($inp,&wparam(0)); # load Xi
&mov ($Htbl,&wparam(1)); # load Htable
&call (&label("pic_point"));
&set_label("pic_point");
&blindpop("eax");
&lea ("eax",&DWP(&label("rem_4bit")."-".&label("pic_point"),"eax"));
&movz ($Zll,&BP(15,$inp));
&mmx_loop($inp,"eax");
&emms ();
&mov (&DWP(12,$inp),$Zll);
&mov (&DWP(4,$inp),$Zhl);
&mov (&DWP(8,$inp),$Zlh);
&mov (&DWP(0,$inp),$Zhh);
&function_end("gcm_gmult_4bit_mmx");
######################################################################
# Below subroutine is "528B" variant of "4-bit" GCM GHASH function
# (see gcm128.c for details). It provides further 20-40% performance
# improvement over above mentioned "May" version.
&static_label("rem_8bit");
&function_begin("gcm_ghash_4bit_mmx");
{ my ($Zlo,$Zhi) = ("mm7","mm6");
my $rem_8bit = "esi";
my $Htbl = "ebx";
# parameter block
&mov ("eax",&wparam(0)); # Xi
&mov ("ebx",&wparam(1)); # Htable
&mov ("ecx",&wparam(2)); # inp
&mov ("edx",&wparam(3)); # len
&mov ("ebp","esp"); # original %esp
&call (&label("pic_point"));
&set_label ("pic_point");
&blindpop ($rem_8bit);
&lea ($rem_8bit,&DWP(&label("rem_8bit")."-".&label("pic_point"),$rem_8bit));
&sub ("esp",512+16+16); # allocate stack frame...
&and ("esp",-64); # ...and align it
&sub ("esp",16); # place for (u8)(H[]<<4)
&add ("edx","ecx"); # pointer to the end of input
&mov (&DWP(528+16+0,"esp"),"eax"); # save Xi
&mov (&DWP(528+16+8,"esp"),"edx"); # save inp+len
&mov (&DWP(528+16+12,"esp"),"ebp"); # save original %esp
{ my @lo = ("mm0","mm1","mm2");
my @hi = ("mm3","mm4","mm5");
my @tmp = ("mm6","mm7");
my ($off1,$off2,$i) = (0,0,);
&add ($Htbl,128); # optimize for size
&lea ("edi",&DWP(16+128,"esp"));
&lea ("ebp",&DWP(16+256+128,"esp"));
# decompose Htable (low and high parts are kept separately),
# generate Htable[]>>4, (u8)(Htable[]<<4), save to stack...
for ($i=0;$i<18;$i++) {
&mov ("edx",&DWP(16*$i+8-128,$Htbl)) if ($i<16);
&movq ($lo[0],&QWP(16*$i+8-128,$Htbl)) if ($i<16);
&psllq ($tmp[1],60) if ($i>1);
&movq ($hi[0],&QWP(16*$i+0-128,$Htbl)) if ($i<16);
&por ($lo[2],$tmp[1]) if ($i>1);
&movq (&QWP($off1-128,"edi"),$lo[1]) if ($i>0 && $i<17);
&psrlq ($lo[1],4) if ($i>0 && $i<17);
&movq (&QWP($off1,"edi"),$hi[1]) if ($i>0 && $i<17);
&movq ($tmp[0],$hi[1]) if ($i>0 && $i<17);
&movq (&QWP($off2-128,"ebp"),$lo[2]) if ($i>1);
&psrlq ($hi[1],4) if ($i>0 && $i<17);
&movq (&QWP($off2,"ebp"),$hi[2]) if ($i>1);
&shl ("edx",4) if ($i<16);
&mov (&BP($i,"esp"),&LB("edx")) if ($i<16);
unshift (@lo,pop(@lo)); # "rotate" registers
unshift (@hi,pop(@hi));
unshift (@tmp,pop(@tmp));
$off1 += 8 if ($i>0);
$off2 += 8 if ($i>1);
}
}
&movq ($Zhi,&QWP(0,"eax"));
&mov ("ebx",&DWP(8,"eax"));
&mov ("edx",&DWP(12,"eax")); # load Xi
&set_label("outer",16);
{ my $nlo = "eax";
my $dat = "edx";
my @nhi = ("edi","ebp");
my @rem = ("ebx","ecx");
my @red = ("mm0","mm1","mm2");
my $tmp = "mm3";
&xor ($dat,&DWP(12,"ecx")); # merge input data
&xor ("ebx",&DWP(8,"ecx"));
&pxor ($Zhi,&QWP(0,"ecx"));
&lea ("ecx",&DWP(16,"ecx")); # inp+=16
#&mov (&DWP(528+12,"esp"),$dat); # save inp^Xi
&mov (&DWP(528+8,"esp"),"ebx");
&movq (&QWP(528+0,"esp"),$Zhi);
&mov (&DWP(528+16+4,"esp"),"ecx"); # save inp
&xor ($nlo,$nlo);
&rol ($dat,8);
&mov (&LB($nlo),&LB($dat));
&mov ($nhi[1],$nlo);
&and (&LB($nlo),0x0f);
&shr ($nhi[1],4);
&pxor ($red[0],$red[0]);
&rol ($dat,8); # next byte
&pxor ($red[1],$red[1]);
&pxor ($red[2],$red[2]);
# Just like in "May" version modulo-schedule for critical path in
# 'Z.hi ^= rem_8bit[Z.lo&0xff^((u8)H[nhi]<<4)]<<48'. Final 'pxor'
# is scheduled so late that rem_8bit[] has to be shifted *right*
# by 16, which is why last argument to pinsrw is 2, which
# corresponds to <<32=<<48>>16...
for ($j=11,$i=0;$i<15;$i++) {
if ($i>0) {
&pxor ($Zlo,&QWP(16,"esp",$nlo,8)); # Z^=H[nlo]
&rol ($dat,8); # next byte
&pxor ($Zhi,&QWP(16+128,"esp",$nlo,8));
&pxor ($Zlo,$tmp);
&pxor ($Zhi,&QWP(16+256+128,"esp",$nhi[0],8));
&xor (&LB($rem[1]),&BP(0,"esp",$nhi[0])); # rem^(H[nhi]<<4)
} else {
&movq ($Zlo,&QWP(16,"esp",$nlo,8));
&movq ($Zhi,&QWP(16+128,"esp",$nlo,8));
}
&mov (&LB($nlo),&LB($dat));
&mov ($dat,&DWP(528+$j,"esp")) if (--$j%4==0);
&movd ($rem[0],$Zlo);
&movz ($rem[1],&LB($rem[1])) if ($i>0);
&psrlq ($Zlo,8); # Z>>=8
&movq ($tmp,$Zhi);
&mov ($nhi[0],$nlo);
&psrlq ($Zhi,8);
&pxor ($Zlo,&QWP(16+256+0,"esp",$nhi[1],8)); # Z^=H[nhi]>>4
&and (&LB($nlo),0x0f);
&psllq ($tmp,56);
&pxor ($Zhi,$red[1]) if ($i>1);
&shr ($nhi[0],4);
&pinsrw ($red[0],&WP(0,$rem_8bit,$rem[1],2),2) if ($i>0);
unshift (@red,pop(@red)); # "rotate" registers
unshift (@rem,pop(@rem));
unshift (@nhi,pop(@nhi));
}
&pxor ($Zlo,&QWP(16,"esp",$nlo,8)); # Z^=H[nlo]
&pxor ($Zhi,&QWP(16+128,"esp",$nlo,8));
&xor (&LB($rem[1]),&BP(0,"esp",$nhi[0])); # rem^(H[nhi]<<4)
&pxor ($Zlo,$tmp);
&pxor ($Zhi,&QWP(16+256+128,"esp",$nhi[0],8));
&movz ($rem[1],&LB($rem[1]));
&pxor ($red[2],$red[2]); # clear 2nd word
&psllq ($red[1],4);
&movd ($rem[0],$Zlo);
&psrlq ($Zlo,4); # Z>>=4
&movq ($tmp,$Zhi);
&psrlq ($Zhi,4);
&shl ($rem[0],4); # rem<<4
&pxor ($Zlo,&QWP(16,"esp",$nhi[1],8)); # Z^=H[nhi]
&psllq ($tmp,60);
&movz ($rem[0],&LB($rem[0]));
&pxor ($Zlo,$tmp);
&pxor ($Zhi,&QWP(16+128,"esp",$nhi[1],8));
&pinsrw ($red[0],&WP(0,$rem_8bit,$rem[1],2),2);
&pxor ($Zhi,$red[1]);
&movd ($dat,$Zlo);
&pinsrw ($red[2],&WP(0,$rem_8bit,$rem[0],2),3); # last is <<48
&psllq ($red[0],12); # correct by <<16>>4
&pxor ($Zhi,$red[0]);
&psrlq ($Zlo,32);
&pxor ($Zhi,$red[2]);
&mov ("ecx",&DWP(528+16+4,"esp")); # restore inp
&movd ("ebx",$Zlo);
&movq ($tmp,$Zhi); # 01234567
&psllw ($Zhi,8); # 1.3.5.7.
&psrlw ($tmp,8); # .0.2.4.6
&por ($Zhi,$tmp); # 10325476
&bswap ($dat);
&pshufw ($Zhi,$Zhi,0b00011011); # 76543210
&bswap ("ebx");
&cmp ("ecx",&DWP(528+16+8,"esp")); # are we done?
&jne (&label("outer"));
}
&mov ("eax",&DWP(528+16+0,"esp")); # restore Xi
&mov (&DWP(12,"eax"),"edx");
&mov (&DWP(8,"eax"),"ebx");
&movq (&QWP(0,"eax"),$Zhi);
&mov ("esp",&DWP(528+16+12,"esp")); # restore original %esp
&emms ();
}
&function_end("gcm_ghash_4bit_mmx");
}}
if ($sse2) {{
######################################################################
# PCLMULQDQ version.
$Xip="eax";
$Htbl="edx";
$const="ecx";
$inp="esi";
$len="ebx";
($Xi,$Xhi)=("xmm0","xmm1"); $Hkey="xmm2";
($T1,$T2,$T3)=("xmm3","xmm4","xmm5");
($Xn,$Xhn)=("xmm6","xmm7");
&static_label("bswap");
sub clmul64x64_T2 { # minimal "register" pressure
my ($Xhi,$Xi,$Hkey,$HK)=@_;
&movdqa ($Xhi,$Xi); #
&pshufd ($T1,$Xi,0b01001110);
&pshufd ($T2,$Hkey,0b01001110) if (!defined($HK));
&pxor ($T1,$Xi); #
&pxor ($T2,$Hkey) if (!defined($HK));
$HK=$T2 if (!defined($HK));
&pclmulqdq ($Xi,$Hkey,0x00); #######
&pclmulqdq ($Xhi,$Hkey,0x11); #######
&pclmulqdq ($T1,$HK,0x00); #######
&xorps ($T1,$Xi); #
&xorps ($T1,$Xhi); #
&movdqa ($T2,$T1); #
&psrldq ($T1,8);
&pslldq ($T2,8); #
&pxor ($Xhi,$T1);
&pxor ($Xi,$T2); #
}
sub clmul64x64_T3 {
# Even though this subroutine offers visually better ILP, it
# was empirically found to be a tad slower than above version.
# At least in gcm_ghash_clmul context. But it's just as well,
# because loop modulo-scheduling is possible only thanks to
# minimized "register" pressure...
my ($Xhi,$Xi,$Hkey)=@_;
&movdqa ($T1,$Xi); #
&movdqa ($Xhi,$Xi);
&pclmulqdq ($Xi,$Hkey,0x00); #######
&pclmulqdq ($Xhi,$Hkey,0x11); #######
&pshufd ($T2,$T1,0b01001110); #
&pshufd ($T3,$Hkey,0b01001110);
&pxor ($T2,$T1); #
&pxor ($T3,$Hkey);
&pclmulqdq ($T2,$T3,0x00); #######
&pxor ($T2,$Xi); #
&pxor ($T2,$Xhi); #
&movdqa ($T3,$T2); #
&psrldq ($T2,8);
&pslldq ($T3,8); #
&pxor ($Xhi,$T2);
&pxor ($Xi,$T3); #
}
if (1) { # Algorithm 9 with <<1 twist.
# Reduction is shorter and uses only two
# temporary registers, which makes it better
# candidate for interleaving with 64x64
# multiplication. Pre-modulo-scheduled loop
# was found to be ~20% faster than Algorithm 5
# below. Algorithm 9 was therefore chosen for
# further optimization...
sub reduction_alg9 { # 17/11 times faster than Intel version
my ($Xhi,$Xi) = @_;
# 1st phase
&movdqa ($T2,$Xi); #
&movdqa ($T1,$Xi);
&psllq ($Xi,5);
&pxor ($T1,$Xi); #
&psllq ($Xi,1);
&pxor ($Xi,$T1); #
&psllq ($Xi,57); #
&movdqa ($T1,$Xi); #
&pslldq ($Xi,8);
&psrldq ($T1,8); #
&pxor ($Xi,$T2);
&pxor ($Xhi,$T1); #
# 2nd phase
&movdqa ($T2,$Xi);
&psrlq ($Xi,1);
&pxor ($Xhi,$T2); #
&pxor ($T2,$Xi);
&psrlq ($Xi,5);
&pxor ($Xi,$T2); #
&psrlq ($Xi,1); #
&pxor ($Xi,$Xhi) #
}
&function_begin_B("gcm_init_clmul");
&mov ($Htbl,&wparam(0));
&mov ($Xip,&wparam(1));
&call (&label("pic"));
&set_label("pic");
&blindpop ($const);
&lea ($const,&DWP(&label("bswap")."-".&label("pic"),$const));
&movdqu ($Hkey,&QWP(0,$Xip));
&pshufd ($Hkey,$Hkey,0b01001110);# dword swap
# <<1 twist
&pshufd ($T2,$Hkey,0b11111111); # broadcast uppermost dword
&movdqa ($T1,$Hkey);
&psllq ($Hkey,1);
&pxor ($T3,$T3); #
&psrlq ($T1,63);
&pcmpgtd ($T3,$T2); # broadcast carry bit
&pslldq ($T1,8);
&por ($Hkey,$T1); # H<<=1
# magic reduction
&pand ($T3,&QWP(16,$const)); # 0x1c2_polynomial
&pxor ($Hkey,$T3); # if(carry) H^=0x1c2_polynomial
# calculate H^2
&movdqa ($Xi,$Hkey);
&clmul64x64_T2 ($Xhi,$Xi,$Hkey);
&reduction_alg9 ($Xhi,$Xi);
&pshufd ($T1,$Hkey,0b01001110);
&pshufd ($T2,$Xi,0b01001110);
&pxor ($T1,$Hkey); # Karatsuba pre-processing
&movdqu (&QWP(0,$Htbl),$Hkey); # save H
&pxor ($T2,$Xi); # Karatsuba pre-processing
&movdqu (&QWP(16,$Htbl),$Xi); # save H^2
&palignr ($T2,$T1,8); # low part is H.lo^H.hi
&movdqu (&QWP(32,$Htbl),$T2); # save Karatsuba "salt"
&ret ();
&function_end_B("gcm_init_clmul");
&function_begin_B("gcm_gmult_clmul");
&mov ($Xip,&wparam(0));
&mov ($Htbl,&wparam(1));
&call (&label("pic"));
&set_label("pic");
&blindpop ($const);
&lea ($const,&DWP(&label("bswap")."-".&label("pic"),$const));
&movdqu ($Xi,&QWP(0,$Xip));
&movdqa ($T3,&QWP(0,$const));
&movups ($Hkey,&QWP(0,$Htbl));
&pshufb ($Xi,$T3);
&movups ($T2,&QWP(32,$Htbl));
&clmul64x64_T2 ($Xhi,$Xi,$Hkey,$T2);
&reduction_alg9 ($Xhi,$Xi);
&pshufb ($Xi,$T3);
&movdqu (&QWP(0,$Xip),$Xi);
&ret ();
&function_end_B("gcm_gmult_clmul");
&function_begin("gcm_ghash_clmul");
&mov ($Xip,&wparam(0));
&mov ($Htbl,&wparam(1));
&mov ($inp,&wparam(2));
&mov ($len,&wparam(3));
&call (&label("pic"));
&set_label("pic");
&blindpop ($const);
&lea ($const,&DWP(&label("bswap")."-".&label("pic"),$const));
&movdqu ($Xi,&QWP(0,$Xip));
&movdqa ($T3,&QWP(0,$const));
&movdqu ($Hkey,&QWP(0,$Htbl));
&pshufb ($Xi,$T3);
&sub ($len,0x10);
&jz (&label("odd_tail"));
#######
# Xi+2 =[H*(Ii+1 + Xi+1)] mod P =
# [(H*Ii+1) + (H*Xi+1)] mod P =
# [(H*Ii+1) + H^2*(Ii+Xi)] mod P
#
&movdqu ($T1,&QWP(0,$inp)); # Ii
&movdqu ($Xn,&QWP(16,$inp)); # Ii+1
&pshufb ($T1,$T3);
&pshufb ($Xn,$T3);
&movdqu ($T3,&QWP(32,$Htbl));
&pxor ($Xi,$T1); # Ii+Xi
&pshufd ($T1,$Xn,0b01001110); # H*Ii+1
&movdqa ($Xhn,$Xn);
&pxor ($T1,$Xn); #
&lea ($inp,&DWP(32,$inp)); # i+=2
&pclmulqdq ($Xn,$Hkey,0x00); #######
&pclmulqdq ($Xhn,$Hkey,0x11); #######
&pclmulqdq ($T1,$T3,0x00); #######
&movups ($Hkey,&QWP(16,$Htbl)); # load H^2
&nop ();
&sub ($len,0x20);
&jbe (&label("even_tail"));
&jmp (&label("mod_loop"));
&set_label("mod_loop",32);
&pshufd ($T2,$Xi,0b01001110); # H^2*(Ii+Xi)
&movdqa ($Xhi,$Xi);
&pxor ($T2,$Xi); #
&nop ();
&pclmulqdq ($Xi,$Hkey,0x00); #######
&pclmulqdq ($Xhi,$Hkey,0x11); #######
&pclmulqdq ($T2,$T3,0x10); #######
&movups ($Hkey,&QWP(0,$Htbl)); # load H
&xorps ($Xi,$Xn); # (H*Ii+1) + H^2*(Ii+Xi)
&movdqa ($T3,&QWP(0,$const));
&xorps ($Xhi,$Xhn);
&movdqu ($Xhn,&QWP(0,$inp)); # Ii
&pxor ($T1,$Xi); # aggregated Karatsuba post-processing
&movdqu ($Xn,&QWP(16,$inp)); # Ii+1
&pxor ($T1,$Xhi); #
&pshufb ($Xhn,$T3);
&pxor ($T2,$T1); #
&movdqa ($T1,$T2); #
&psrldq ($T2,8);
&pslldq ($T1,8); #
&pxor ($Xhi,$T2);
&pxor ($Xi,$T1); #
&pshufb ($Xn,$T3);
&pxor ($Xhi,$Xhn); # "Ii+Xi", consume early
&movdqa ($Xhn,$Xn); #&clmul64x64_TX ($Xhn,$Xn,$Hkey); H*Ii+1
&movdqa ($T2,$Xi); #&reduction_alg9($Xhi,$Xi); 1st phase
&movdqa ($T1,$Xi);
&psllq ($Xi,5);
&pxor ($T1,$Xi); #
&psllq ($Xi,1);
&pxor ($Xi,$T1); #
&pclmulqdq ($Xn,$Hkey,0x00); #######
&movups ($T3,&QWP(32,$Htbl));
&psllq ($Xi,57); #
&movdqa ($T1,$Xi); #
&pslldq ($Xi,8);
&psrldq ($T1,8); #
&pxor ($Xi,$T2);
&pxor ($Xhi,$T1); #
&pshufd ($T1,$Xhn,0b01001110);
&movdqa ($T2,$Xi); # 2nd phase
&psrlq ($Xi,1);
&pxor ($T1,$Xhn);
&pxor ($Xhi,$T2); #
&pclmulqdq ($Xhn,$Hkey,0x11); #######
&movups ($Hkey,&QWP(16,$Htbl)); # load H^2
&pxor ($T2,$Xi);
&psrlq ($Xi,5);
&pxor ($Xi,$T2); #
&psrlq ($Xi,1); #
&pxor ($Xi,$Xhi) #
&pclmulqdq ($T1,$T3,0x00); #######
&lea ($inp,&DWP(32,$inp));
&sub ($len,0x20);
&ja (&label("mod_loop"));
&set_label("even_tail");
&pshufd ($T2,$Xi,0b01001110); # H^2*(Ii+Xi)
&movdqa ($Xhi,$Xi);
&pxor ($T2,$Xi); #
&pclmulqdq ($Xi,$Hkey,0x00); #######
&pclmulqdq ($Xhi,$Hkey,0x11); #######
&pclmulqdq ($T2,$T3,0x10); #######
&movdqa ($T3,&QWP(0,$const));
&xorps ($Xi,$Xn); # (H*Ii+1) + H^2*(Ii+Xi)
&xorps ($Xhi,$Xhn);
&pxor ($T1,$Xi); # aggregated Karatsuba post-processing
&pxor ($T1,$Xhi); #
&pxor ($T2,$T1); #
&movdqa ($T1,$T2); #
&psrldq ($T2,8);
&pslldq ($T1,8); #
&pxor ($Xhi,$T2);
&pxor ($Xi,$T1); #
&reduction_alg9 ($Xhi,$Xi);
&test ($len,$len);
&jnz (&label("done"));
&movups ($Hkey,&QWP(0,$Htbl)); # load H
&set_label("odd_tail");
&movdqu ($T1,&QWP(0,$inp)); # Ii
&pshufb ($T1,$T3);
&pxor ($Xi,$T1); # Ii+Xi
&clmul64x64_T2 ($Xhi,$Xi,$Hkey); # H*(Ii+Xi)
&reduction_alg9 ($Xhi,$Xi);
&set_label("done");
&pshufb ($Xi,$T3);
&movdqu (&QWP(0,$Xip),$Xi);
&function_end("gcm_ghash_clmul");
} else { # Algorithm 5. Kept for reference purposes.
sub reduction_alg5 { # 19/16 times faster than Intel version
my ($Xhi,$Xi)=@_;
# <<1
&movdqa ($T1,$Xi); #
&movdqa ($T2,$Xhi);
&pslld ($Xi,1);
&pslld ($Xhi,1); #
&psrld ($T1,31);
&psrld ($T2,31); #
&movdqa ($T3,$T1);
&pslldq ($T1,4);
&psrldq ($T3,12); #
&pslldq ($T2,4);
&por ($Xhi,$T3); #
&por ($Xi,$T1);
&por ($Xhi,$T2); #
# 1st phase
&movdqa ($T1,$Xi);
&movdqa ($T2,$Xi);
&movdqa ($T3,$Xi); #
&pslld ($T1,31);
&pslld ($T2,30);
&pslld ($Xi,25); #
&pxor ($T1,$T2);
&pxor ($T1,$Xi); #
&movdqa ($T2,$T1); #
&pslldq ($T1,12);
&psrldq ($T2,4); #
&pxor ($T3,$T1);
# 2nd phase
&pxor ($Xhi,$T3); #
&movdqa ($Xi,$T3);
&movdqa ($T1,$T3);
&psrld ($Xi,1); #
&psrld ($T1,2);
&psrld ($T3,7); #
&pxor ($Xi,$T1);
&pxor ($Xhi,$T2);
&pxor ($Xi,$T3); #
&pxor ($Xi,$Xhi); #
}
&function_begin_B("gcm_init_clmul");
&mov ($Htbl,&wparam(0));
&mov ($Xip,&wparam(1));
&call (&label("pic"));
&set_label("pic");
&blindpop ($const);
&lea ($const,&DWP(&label("bswap")."-".&label("pic"),$const));
&movdqu ($Hkey,&QWP(0,$Xip));
&pshufd ($Hkey,$Hkey,0b01001110);# dword swap
# calculate H^2
&movdqa ($Xi,$Hkey);
&clmul64x64_T3 ($Xhi,$Xi,$Hkey);
&reduction_alg5 ($Xhi,$Xi);
&movdqu (&QWP(0,$Htbl),$Hkey); # save H
&movdqu (&QWP(16,$Htbl),$Xi); # save H^2
&ret ();
&function_end_B("gcm_init_clmul");
&function_begin_B("gcm_gmult_clmul");
&mov ($Xip,&wparam(0));
&mov ($Htbl,&wparam(1));
&call (&label("pic"));
&set_label("pic");
&blindpop ($const);
&lea ($const,&DWP(&label("bswap")."-".&label("pic"),$const));
&movdqu ($Xi,&QWP(0,$Xip));
&movdqa ($Xn,&QWP(0,$const));
&movdqu ($Hkey,&QWP(0,$Htbl));
&pshufb ($Xi,$Xn);
&clmul64x64_T3 ($Xhi,$Xi,$Hkey);
&reduction_alg5 ($Xhi,$Xi);
&pshufb ($Xi,$Xn);
&movdqu (&QWP(0,$Xip),$Xi);
&ret ();
&function_end_B("gcm_gmult_clmul");
&function_begin("gcm_ghash_clmul");
&mov ($Xip,&wparam(0));
&mov ($Htbl,&wparam(1));
&mov ($inp,&wparam(2));
&mov ($len,&wparam(3));
&call (&label("pic"));
&set_label("pic");
&blindpop ($const);
&lea ($const,&DWP(&label("bswap")."-".&label("pic"),$const));
&movdqu ($Xi,&QWP(0,$Xip));
&movdqa ($T3,&QWP(0,$const));
&movdqu ($Hkey,&QWP(0,$Htbl));
&pshufb ($Xi,$T3);
&sub ($len,0x10);
&jz (&label("odd_tail"));
#######
# Xi+2 =[H*(Ii+1 + Xi+1)] mod P =
# [(H*Ii+1) + (H*Xi+1)] mod P =
# [(H*Ii+1) + H^2*(Ii+Xi)] mod P
#
&movdqu ($T1,&QWP(0,$inp)); # Ii
&movdqu ($Xn,&QWP(16,$inp)); # Ii+1
&pshufb ($T1,$T3);
&pshufb ($Xn,$T3);
&pxor ($Xi,$T1); # Ii+Xi
&clmul64x64_T3 ($Xhn,$Xn,$Hkey); # H*Ii+1
&movdqu ($Hkey,&QWP(16,$Htbl)); # load H^2
&sub ($len,0x20);
&lea ($inp,&DWP(32,$inp)); # i+=2
&jbe (&label("even_tail"));
&set_label("mod_loop");
&clmul64x64_T3 ($Xhi,$Xi,$Hkey); # H^2*(Ii+Xi)
&movdqu ($Hkey,&QWP(0,$Htbl)); # load H
&pxor ($Xi,$Xn); # (H*Ii+1) + H^2*(Ii+Xi)
&pxor ($Xhi,$Xhn);
&reduction_alg5 ($Xhi,$Xi);
#######
&movdqa ($T3,&QWP(0,$const));
&movdqu ($T1,&QWP(0,$inp)); # Ii
&movdqu ($Xn,&QWP(16,$inp)); # Ii+1
&pshufb ($T1,$T3);
&pshufb ($Xn,$T3);
&pxor ($Xi,$T1); # Ii+Xi
&clmul64x64_T3 ($Xhn,$Xn,$Hkey); # H*Ii+1
&movdqu ($Hkey,&QWP(16,$Htbl)); # load H^2
&sub ($len,0x20);
&lea ($inp,&DWP(32,$inp));
&ja (&label("mod_loop"));
&set_label("even_tail");
&clmul64x64_T3 ($Xhi,$Xi,$Hkey); # H^2*(Ii+Xi)
&pxor ($Xi,$Xn); # (H*Ii+1) + H^2*(Ii+Xi)
&pxor ($Xhi,$Xhn);
&reduction_alg5 ($Xhi,$Xi);
&movdqa ($T3,&QWP(0,$const));
&test ($len,$len);
&jnz (&label("done"));
&movdqu ($Hkey,&QWP(0,$Htbl)); # load H
&set_label("odd_tail");
&movdqu ($T1,&QWP(0,$inp)); # Ii
&pshufb ($T1,$T3);
&pxor ($Xi,$T1); # Ii+Xi
&clmul64x64_T3 ($Xhi,$Xi,$Hkey); # H*(Ii+Xi)
&reduction_alg5 ($Xhi,$Xi);
&movdqa ($T3,&QWP(0,$const));
&set_label("done");
&pshufb ($Xi,$T3);
&movdqu (&QWP(0,$Xip),$Xi);
&function_end("gcm_ghash_clmul");
}
&set_label("bswap",64);
&data_byte(15,14,13,12,11,10,9,8,7,6,5,4,3,2,1,0);
&data_byte(1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0xc2); # 0x1c2_polynomial
&set_label("rem_8bit",64);
&data_short(0x0000,0x01C2,0x0384,0x0246,0x0708,0x06CA,0x048C,0x054E);
&data_short(0x0E10,0x0FD2,0x0D94,0x0C56,0x0918,0x08DA,0x0A9C,0x0B5E);
&data_short(0x1C20,0x1DE2,0x1FA4,0x1E66,0x1B28,0x1AEA,0x18AC,0x196E);
&data_short(0x1230,0x13F2,0x11B4,0x1076,0x1538,0x14FA,0x16BC,0x177E);
&data_short(0x3840,0x3982,0x3BC4,0x3A06,0x3F48,0x3E8A,0x3CCC,0x3D0E);
&data_short(0x3650,0x3792,0x35D4,0x3416,0x3158,0x309A,0x32DC,0x331E);
&data_short(0x2460,0x25A2,0x27E4,0x2626,0x2368,0x22AA,0x20EC,0x212E);
&data_short(0x2A70,0x2BB2,0x29F4,0x2836,0x2D78,0x2CBA,0x2EFC,0x2F3E);
&data_short(0x7080,0x7142,0x7304,0x72C6,0x7788,0x764A,0x740C,0x75CE);
&data_short(0x7E90,0x7F52,0x7D14,0x7CD6,0x7998,0x785A,0x7A1C,0x7BDE);
&data_short(0x6CA0,0x6D62,0x6F24,0x6EE6,0x6BA8,0x6A6A,0x682C,0x69EE);
&data_short(0x62B0,0x6372,0x6134,0x60F6,0x65B8,0x647A,0x663C,0x67FE);
&data_short(0x48C0,0x4902,0x4B44,0x4A86,0x4FC8,0x4E0A,0x4C4C,0x4D8E);
&data_short(0x46D0,0x4712,0x4554,0x4496,0x41D8,0x401A,0x425C,0x439E);
&data_short(0x54E0,0x5522,0x5764,0x56A6,0x53E8,0x522A,0x506C,0x51AE);
&data_short(0x5AF0,0x5B32,0x5974,0x58B6,0x5DF8,0x5C3A,0x5E7C,0x5FBE);
&data_short(0xE100,0xE0C2,0xE284,0xE346,0xE608,0xE7CA,0xE58C,0xE44E);
&data_short(0xEF10,0xEED2,0xEC94,0xED56,0xE818,0xE9DA,0xEB9C,0xEA5E);
&data_short(0xFD20,0xFCE2,0xFEA4,0xFF66,0xFA28,0xFBEA,0xF9AC,0xF86E);
&data_short(0xF330,0xF2F2,0xF0B4,0xF176,0xF438,0xF5FA,0xF7BC,0xF67E);
&data_short(0xD940,0xD882,0xDAC4,0xDB06,0xDE48,0xDF8A,0xDDCC,0xDC0E);
&data_short(0xD750,0xD692,0xD4D4,0xD516,0xD058,0xD19A,0xD3DC,0xD21E);
&data_short(0xC560,0xC4A2,0xC6E4,0xC726,0xC268,0xC3AA,0xC1EC,0xC02E);
&data_short(0xCB70,0xCAB2,0xC8F4,0xC936,0xCC78,0xCDBA,0xCFFC,0xCE3E);
&data_short(0x9180,0x9042,0x9204,0x93C6,0x9688,0x974A,0x950C,0x94CE);
&data_short(0x9F90,0x9E52,0x9C14,0x9DD6,0x9898,0x995A,0x9B1C,0x9ADE);
&data_short(0x8DA0,0x8C62,0x8E24,0x8FE6,0x8AA8,0x8B6A,0x892C,0x88EE);
&data_short(0x83B0,0x8272,0x8034,0x81F6,0x84B8,0x857A,0x873C,0x86FE);
&data_short(0xA9C0,0xA802,0xAA44,0xAB86,0xAEC8,0xAF0A,0xAD4C,0xAC8E);
&data_short(0xA7D0,0xA612,0xA454,0xA596,0xA0D8,0xA11A,0xA35C,0xA29E);
&data_short(0xB5E0,0xB422,0xB664,0xB7A6,0xB2E8,0xB32A,0xB16C,0xB0AE);
&data_short(0xBBF0,0xBA32,0xB874,0xB9B6,0xBCF8,0xBD3A,0xBF7C,0xBEBE);
}} # $sse2
&set_label("rem_4bit",64);
&data_word(0,0x0000<<$S,0,0x1C20<<$S,0,0x3840<<$S,0,0x2460<<$S);
&data_word(0,0x7080<<$S,0,0x6CA0<<$S,0,0x48C0<<$S,0,0x54E0<<$S);
&data_word(0,0xE100<<$S,0,0xFD20<<$S,0,0xD940<<$S,0,0xC560<<$S);
&data_word(0,0x9180<<$S,0,0x8DA0<<$S,0,0xA9C0<<$S,0,0xB5E0<<$S);
}}} # !$x86only
&asciz("GHASH for x86, CRYPTOGAMS by <appro\@openssl.org>");
&asm_finish();
close STDOUT or die "error closing STDOUT: $!";
# A question was risen about choice of vanilla MMX. Or rather why wasn't
# SSE2 chosen instead? In addition to the fact that MMX runs on legacy
# CPUs such as PIII, "4-bit" MMX version was observed to provide better
# performance than *corresponding* SSE2 one even on contemporary CPUs.
# SSE2 results were provided by Peter-Michael Hager. He maintains SSE2
# implementation featuring full range of lookup-table sizes, but with
# per-invocation lookup table setup. Latter means that table size is
# chosen depending on how much data is to be hashed in every given call,
# more data - larger table. Best reported result for Core2 is ~4 cycles
# per processed byte out of 64KB block. This number accounts even for
# 64KB table setup overhead. As discussed in gcm128.c we choose to be
# more conservative in respect to lookup table sizes, but how do the
# results compare? Minimalistic "256B" MMX version delivers ~11 cycles
# on same platform. As also discussed in gcm128.c, next in line "8-bit
# Shoup's" or "4KB" method should deliver twice the performance of
# "256B" one, in other words not worse than ~6 cycles per byte. It
# should be also be noted that in SSE2 case improvement can be "super-
# linear," i.e. more than twice, mostly because >>8 maps to single
# instruction on SSE2 register. This is unlike "4-bit" case when >>4
# maps to same amount of instructions in both MMX and SSE2 cases.
# Bottom line is that switch to SSE2 is considered to be justifiable
# only in case we choose to implement "8-bit" method...