# details see http://www.openssl.org/~appro/cryptogams/.
# ====================================================================
#
-# March 2010
+# 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 MMX. Former will be executed on
-# 486 and Pentium, latter on all others. Performance results are for
-# streamed GHASH subroutine and are expressed in cycles per processed
-# byte, less is better:
+# 486 and Pentium, latter on all others. MMX 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(*) MMX assembler x86 assembler
#
-# Pentium 100/112(**) - 50
-# PIII 63 /77 16 24
-# P4 96 /122 30 84(***)
-# Opteron 50 /71 21 30
-# Core2 54 /68 12.5 18
+# 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
#
# (*) 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 MMX 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 >2-3 times faster than gcc-generated code. To
+# To summarize, it's >2-5 times faster than gcc-generated code. To
# anchor it to something else SHA1 assembler processes one byte in
-# 11-13 cycles on contemporary x86 cores.
+# 11-13 cycles on contemporary x86 cores. As for choice of MMX in
+# particular, see comment at the end of the file...
# May 2010
#
-# Add PCLMULQDQ version performing at 2.13 cycles per processed byte.
+# 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
# 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 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, only for fused GCM mode. But
-# we can estimate it by subtracting CTR performance result provided
-# in "AES Instruction Set" white paper: 3.54-1.38=2.16 cycles per
-# processed byte or 5% off the estimate. It should be noted though
-# that 3.54 is GCM result for 16KB block size, while 1.38 is CTR for
-# 1KB block size, meaning that real number is likely to be a bit
-# further from estimate.
+# 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 fusing GHASH with CTR 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 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 per processed byte. Or in other words,
-# depending on how well we can interleave reduction and one of the
-# two multiplications the performance should be betwen 1.91 and 2.16.
-# As already mentioned, this implementation processes one byte [out
-# of 1KB buffer] in 2.13 cycles, while x86_64 counterpart - in 2.07.
-# x86_64 performance is better, because larger register bank allows
-# to interleave reduction and multiplication better.
+# 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 betwen
+# 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
# 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 <dwmw2@infradead.org> 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.
$0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1;
push(@INC,"${dir}","${dir}../../perlasm");
&static_label("rem_4bit");
+if (0) {{ # "May" MMX version is kept for reference...
+
+$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 ยต-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");
+\f
+# 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),$Zhh);
+
+ &stack_pop(4+1);
+&function_end("gcm_ghash_4bit_mmx");
+\f
+}} else {{ # "June" MMX version...
+ # ... has slower "April" gcm_gmult_4bit_mmx with folded
+ # loop. This is done to conserve code size...
+$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%
&mov (&DWP(0,$inp),$Zhh);
&function_end("gcm_gmult_4bit_mmx");
\f
-# 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,$Zhh));
- &jmp (&label("mmx_outer_loop"));
+######################################################################
+# Below subroutine is "528B" variant of "4-bit" GCM GHASH function
+# (see gcm128.c for details). It provides further 20-40% performance
+# improvement over above mentioned "May" version.
- &set_label("mmx_outer_loop",16);
- &xor ($Zll,&DWP(12,$inp));
- &xor ($Zhl,&DWP(4,$inp));
- &xor ($Zlh,&DWP(8,$inp));
- &xor ($Zhh,&DWP(0,$inp));
- &mov (&DWP(12,"esp"),$Zll);
- &mov (&DWP(4,"esp"),$Zhl);
- &mov (&DWP(8,"esp"),$Zlh);
- &mov (&DWP(0,"esp"),$Zhh);
+&static_label("rem_8bit");
- &shr ($Zll,24);
+&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 $off1=0,$off2=0,$i;
+
+ &add ($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],$red[2]);
+
+ # Just like in "May" verson modulo-schedule for critical path in
+ # 'Z.hi ^= rem_8bit[Z.lo&0xff^((u8)H[nhi]<<4)]<<48'. Final 'pxor'
+ # is scheduled so late that rem_8bit[] has to be shifted *right*
+ # by 16, which is why last argument to pinsrw is 2, which
+ # corresponds to <<32=<<48>>16...
+ for ($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",$nlo,8));
- &mmx_loop("esp","eax");
+ &pxor ($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",$nlo,8));
+ }
- &lea ($inp,&DWP(16,$inp));
- &cmp ($inp,&wparam(3));
- &jb (&label("mmx_outer_loop"));
+ &mov (&LB($nlo),&LB($dat));
+ &mov ($dat,&DWP(528+$j,"esp")) if (--$j%4==0);
- &mov ($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);
+ &movd ($rem[0],$Zlo);
+ &movz ($rem[1],&LB($rem[1])) if ($i>0);
+ &psrlq ($Zlo,8); # Z>>=8
- &stack_pop(4+1);
+ &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"),$Zhi);
+
+ &mov ("esp",&DWP(528+16+12,"esp")); # restore original %esp
+ &emms ();
+}
&function_end("gcm_ghash_4bit_mmx");
+}}
\f
if ($sse2) {{
######################################################################
&static_label("bswap");
+sub pclmulqdq
+{ my($dst,$src,$imm)=@_;
+ if ("$dst:$src" =~ /xmm([0-7]):xmm([0-7])/)
+ { &data_byte(0x66,0x0f,0x3a,0x44,0xc0|($1<<3)|$2,$imm); }
+}
+
sub clmul64x64_T2 { # minimal "register" pressure
my ($Xhi,$Xi,$Hkey)=@_;
&pclmulqdq ($Xi,$Hkey,0x00); #######
&pclmulqdq ($Xhi,$Hkey,0x11); #######
&pclmulqdq ($T1,$T2,0x00); #######
- &pxor ($T1,$Xi); #
- &pxor ($T1,$Xhi); #
+ &xorps ($T1,$Xi); #
+ &xorps ($T1,$Xhi); #
&movdqa ($T2,$T1); #
&psrldq ($T1,8);
# candidate for interleaving with 64x64
# multiplication. Pre-modulo-scheduled loop
# was found to be ~20% faster than Algorithm 5
- # below. Algorithm 9 was then chosen and
- # optimized further...
+ # below. Algorithm 9 was therefore chosen for
+ # further optimization...
sub reduction_alg9 { # 17/13 times faster than Intel version
my ($Xhi,$Xi) = @_;
&psllq ($Xi,57); #
&movdqa ($T2,$Xi); #
&pslldq ($Xi,8);
- &psrldq ($T2,8); #
+ &psrldq ($T2,8); #
&pxor ($Xi,$T1);
&pxor ($Xhi,$T2); #
&movdqu ($Xi,&QWP(0,$Xip));
&movdqa ($T3,&QWP(0,$const));
- &movdqu ($Hkey,&QWP(0,$Htbl));
+ &movups ($Hkey,&QWP(0,$Htbl));
&pshufb ($Xi,$T3);
&clmul64x64_T2 ($Xhi,$Xi,$Hkey);
&pxor ($Xi,$T1); # Ii+Xi
&clmul64x64_T2 ($Xhn,$Xn,$Hkey); # H*Ii+1
- &movdqu ($Hkey,&QWP(16,$Htbl)); # load H^2
+ &movups ($Hkey,&QWP(16,$Htbl)); # load H^2
&lea ($inp,&DWP(32,$inp)); # i+=2
&sub ($len,0x20);
&set_label("mod_loop");
&clmul64x64_T2 ($Xhi,$Xi,$Hkey); # H^2*(Ii+Xi)
&movdqu ($T1,&QWP(0,$inp)); # Ii
- &movdqu ($Hkey,&QWP(0,$Htbl)); # load H
+ &movups ($Hkey,&QWP(0,$Htbl)); # load H
&pxor ($Xi,$Xn); # (H*Ii+1) + H^2*(Ii+Xi)
&pxor ($Xhi,$Xhn);
&pxor ($Xi,$T2); #
&pclmulqdq ($T1,$T3,0x00); #######
- &movdqu ($Hkey,&QWP(16,$Htbl)); # load H^2
- &pxor ($T1,$Xn); #
- &pxor ($T1,$Xhn); #
+ &movups ($Hkey,&QWP(16,$Htbl)); # load H^2
+ &xorps ($T1,$Xn); #
+ &xorps ($T1,$Xhn); #
&movdqa ($T3,$T1); #
&psrldq ($T1,8);
&test ($len,$len);
&jnz (&label("done"));
- &movdqu ($Hkey,&QWP(0,$Htbl)); # load H
+ &movups ($Hkey,&QWP(0,$Htbl)); # load H
&set_label("odd_tail");
&movdqu ($T1,&QWP(0,$inp)); # Ii
&pshufb ($T1,$T3);
}} # $sse2
&set_label("rem_4bit",64);
- &data_word(0,0x0000<<16,0,0x1C20<<16,0,0x3840<<16,0,0x2460<<16);
- &data_word(0,0x7080<<16,0,0x6CA0<<16,0,0x48C0<<16,0,0x54E0<<16);
- &data_word(0,0xE100<<16,0,0xFD20<<16,0,0xD940<<16,0,0xC560<<16);
- &data_word(0,0x9180<<16,0,0x8DA0<<16,0,0xA9C0<<16,0,0xB5E0<<16);
+ &data_word(0,0x0000<<$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);
+&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);
}}} # !$x86only
&asciz("GHASH for x86, CRYPTOGAMS by <appro\@openssl.org>");
&asm_finish();
+
+# 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...
projects / openssl.git / blobdiff