X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=crypto%2Fmodes%2Fasm%2Fghash-x86.pl;h=25a16a355ba73312890e91dc5d528d5c930f2583;hp=63e76c1da67d34964caef3c0f533f69a0b6053fc;hb=f9c5e5d92e75ccff046774494b9904d849148e5f;hpb=480cd6ab6e994626177de701c418264257954b03

diff --git a/crypto/modes/asm/ghash-x86.pl b/crypto/modes/asm/ghash-x86.pl
index 63e76c1da6..25a16a355b 100644
--- a/crypto/modes/asm/ghash-x86.pl
+++ b/crypto/modes/asm/ghash-x86.pl
@@ -7,150 +7,128 @@
 # details see http://www.openssl.org/~appro/cryptogams/.
 # ====================================================================
 #
-# March 2010
+# March, May, June 2010
 #
-# The module implements "4-bit" Galois field multiplication and
-# streamed GHASH function. "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:
+# 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(*)	MMX assembler	x86 assembler
+#		gcc 2.95.3(*)	SSE assembler	x86 assembler
 #
-# Pentium	100/112(**)	-		50
-# PIII		63 /77		16		24
-# P4		96 /122		30		84(***)
-# Opteron	50 /71		21		30
-# Core2		63 /102		19		28
+# 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 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 2-3 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.
+# ~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 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
+# capacity. Otherwise improvement has to be weighed agiainst 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 <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");
 require "x86asm.pl";
 
-&asm_init($ARGV[0],"gcm-x86.pl",$x86only = $ARGV[$#ARGV] eq "386");
+&asm_init($ARGV[0],"ghash-x86.pl",$x86only = $ARGV[$#ARGV] eq "386");
 
-&static_label("rem_4bit") if (!$x86only);
+$sse2=0;
+for (@ARGV) { $sse2=1 if (/-DOPENSSL_IA32_SSE2/); }
 
-$Zhh  = "ebp";
-$Zhl  = "edx";
-$Zlh  = "ecx";
-$Zll  = "ebx";
+($Zhh,$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
-		# 1.7x code size reduction. Well, *overall* 1.7x,
-		# x86-specific code itself shrinks by 2.5x...
-
-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, 50% better
-# on PIII and Core2... 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 = "mm0";
-    my $Zhi = "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);
-	&pxor	($Zlo,&QWP(8,$Htbl,$nhi));
-	&movq	($tmp,$Zhi);
-	&psrlq	($Zhi,4);
-	&mov	(&LB($nlo),&BP(0,$inp,$cnt));
-	&dec	($cnt);
-	&psllq	($tmp,60);
-	&pxor	($Zhi,&QWP(0,$rem_4bit,$rem,8));
-	&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	($rem,0xf);
-	&pxor	($Zlo,&QWP(8,$Htbl,$nhi));
-	&movq	($tmp,$Zhi);
-	&psrlq	($Zhi,4);
-	&psllq	($tmp,60);
-	&pxor	($Zhi,&QWP(0,$rem_4bit,$rem,8));
-	&movd	($rem,$Zlo);
-	&pxor	($Zhi,&QWP(0,$Htbl,$nhi));
-	&mov	($nhi,$nlo);
-	&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);
-}
+		# 2.5x x86-specific code size reduction.
 
 sub x86_loop {
     my $off = shift;
@@ -245,33 +223,30 @@ if ($unroll) {
     &function_end_B("_x86_gmult_4bit_inner");
 }
 
-&function_begin("gcm_gmult_4bit");
-    if (!$x86only) {
-	&call	(&label("pic_point"));
-	&set_label("pic_point");
-	&blindpop("eax");
-	&picmeup("ebp","OPENSSL_ia32cap_P","eax",&label("pic_point"));
-	&bt	(&DWP(0,"ebp"),23);	# check for MMX bit
-	&jnc	(&label("x86"));
-
-	&lea	("eax",&DWP(&label("rem_4bit")."-".&label("pic_point"),"eax"));
-
-	&mov	($inp,&wparam(0));	# load Xi
-	&mov	($Htbl,&wparam(1));	# load Htable
-
-	&movz	($Zll,&BP(15,$inp));
-
-	&mmx_loop($inp,"eax");
+sub deposit_rem_4bit {
+    my $bias = shift;
 
-	&emms	();
-	&mov	(&DWP(12,$inp),$Zll);
-	&mov	(&DWP(4,$inp),$Zhl);
-	&mov	(&DWP(8,$inp),$Zlh);
-	&mov	(&DWP(0,$inp),$Zhh);
+	&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_end_A();
-    &set_label("x86",16);
-    }
+&function_begin("gcm_gmult_4bit".$suffix);
 	&stack_push(16+4+1);			# +1 for stack alignment
 	&mov	($inp,&wparam(0));		# load Xi
 	&mov	($Htbl,&wparam(1));		# load Htable
@@ -302,69 +277,16 @@ if ($unroll) {
 	&mov	(&DWP(4,$inp),$Zhl);
 	&mov	(&DWP(0,$inp),$Zhh);
 	&stack_pop(16+4+1);
-&function_end("gcm_gmult_4bit");
-
-# Streamed version performs 20% better on P4, 7% on Opteron,
-# 10% on Core2 and PIII...
-&function_begin("gcm_ghash_4bit");
-    if (!$x86only) {
-	&call	(&label("pic_point"));
-	&set_label("pic_point");
-	&blindpop("eax");
-	&picmeup("ebp","OPENSSL_ia32cap_P","eax",&label("pic_point"));
-	&bt	(&DWP(0,"ebp"),23);	# check for MMX bit
-	&jnc	(&label("x86"));
-
-	&lea	("eax",&DWP(&label("rem_4bit")."-".&label("pic_point"),"eax"));
-
-	&mov	($inp,&wparam(0));	# load in
-	&mov	($Zlh,&wparam(1));	# load len
-	&mov	($Zhh,&wparam(2));	# load Xi
-	&mov	($Htbl,&wparam(3));	# load Htable
-	&add	($Zlh,$inp);
-	&mov	(&wparam(1),$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));
-
-    &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);
-
-	&shr	($Zll,24);
-
-	&mmx_loop("esp","eax");
-
-	&lea	($inp,&DWP(16,$inp));
-	&cmp	($inp,&wparam(1));
-	&jb	(&label("mmx_outer_loop"));
+&function_end("gcm_gmult_4bit".$suffix);
 
-	&mov	($inp,&wparam(2));	# load Xi
-	&emms	();
-	&mov	(&DWP(12,$inp),$Zll);
-	&mov	(&DWP(4,$inp),$Zhl);
-	&mov	(&DWP(8,$inp),$Zlh);
-	&mov	(&DWP(0,$inp),$Zhh);
-
-	&stack_pop(4+1);
-	&function_end_A();
-    &set_label("x86",16);
-    }
+&function_begin("gcm_ghash_4bit".$suffix);
 	&stack_push(16+4+1);			# +1 for 64-bit alignment
-	&mov	($inp,&wparam(0));		# load in
-	&mov	("ecx",&wparam(1));		# load len
-	&mov	($Zll,&wparam(2));		# load Xi
-	&mov	($Htbl,&wparam(3));		# load Htable
+	&mov	($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(1),"ecx");
+	&mov	(&wparam(3),"ecx");
 
 	&mov	($Zhh,&DWP(0,$Zll));		# load Xi[16]
 	&mov	($Zhl,&DWP(4,$Zll));
@@ -390,48 +312,1031 @@ if ($unroll) {
 		&call	("_x86_gmult_4bit_inner");
 	} else {
 		&x86_loop(0);
-		&mov	($inp,&wparam(0));
+		&mov	($inp,&wparam(2));
 	}
 	&lea	($inp,&DWP(16,$inp));
-	&cmp	($inp,&wparam(1));
-	&mov	(&wparam(0),$inp)	if (!$unroll);
+	&cmp	($inp,&wparam(3));
+	&mov	(&wparam(2),$inp)	if (!$unroll);
 	&jb	(&label("x86_outer_loop"));
 
-	&mov	($inp,&wparam(2));	# load Xi
+	&mov	($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");
+&function_end("gcm_ghash_4bit".$suffix);
+
+if (!$x86only) {{{
 
-sub deposit_rem_4bit {
-    my $bias = shift;
+&static_label("rem_4bit");
 
-	&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);
-}
+if (!$sse2) {{	# pure-MMX "May" version...
 
-if (!$x86only) {
-&set_label("rem_4bit",64);
-	&data_word(0,0x0000<<16,0,0x1C20<<16,0,0x3840<<16,0,0x2460<<16);
-	&data_word(0,0x7080<<16,0,0x6CA0<<16,0,0x48C0<<16,0,0x54E0<<16);
-	&data_word(0,0xE100<<16,0,0xFD20<<16,0,0xD940<<16,0,0xC560<<16);
-	&data_word(0,0x9180<<16,0,0x8DA0<<16,0,0xA9C0<<16,0,0xB5E0<<16);
+$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	($Zhh);
+
+	&ret	();
 }
-&asciz("GHASH for x86, CRYPTOGAMS by <appro\@openssl.org>");
-&asm_finish();
+&function_end_B("_mmx_gmult_4bit_inner");
+
+&function_begin("gcm_gmult_4bit_mmx");
+	&mov	($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],$red[2]);
+
+    # Just like in "May" verson modulo-schedule for critical path in
+    # 'Z.hi ^= rem_8bit[Z.lo&0xff^((u8)H[nhi]<<4)]<<48'. Final 'pxor'
+    # is scheduled so late that rem_8bit[] has to be shifted *right*
+    # by 16, which is why last argument to pinsrw is 2, which
+    # corresponds to <<32=<<48>>16...
+    for ($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",$nlo,8));
+
+	&pxor	($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,$Hkey)=@_;
+
+	&movdqa		($Xhi,$Xi);		#
+	&pshufd		($T1,$Xi,0b01001110);
+	&pshufd		($T2,$Hkey,0b01001110);
+	&pxor		($T1,$Xi);		#
+	&pxor		($T2,$Hkey);
+
+	&pclmulqdq	($Xi,$Hkey,0x00);	#######
+	&pclmulqdq	($Xhi,$Hkey,0x11);	#######
+	&pclmulqdq	($T1,$T2,0x00);		#######
+	&xorps		($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 {	# 17/13 times faster than Intel version
+my ($Xhi,$Xi) = @_;
+
+	# 1st phase
+	&movdqa		($T1,$Xi);		#
+	&psllq		($Xi,1);
+	&pxor		($Xi,$T1);		#
+	&psllq		($Xi,5);		#
+	&pxor		($Xi,$T1);		#
+	&psllq		($Xi,57);		#
+	&movdqa		($T2,$Xi);		#
+	&pslldq		($Xi,8);
+	&psrldq		($T2,8);		#
+	&pxor		($Xi,$T1);
+	&pxor		($Xhi,$T2);		#
+
+	# 2nd phase
+	&movdqa		($T2,$Xi);
+	&psrlq		($Xi,5);
+	&pxor		($Xi,$T2);		#
+	&psrlq		($Xi,1);		#
+	&pxor		($Xi,$T2);		#
+	&pxor		($T2,$Xhi);
+	&psrlq		($Xi,1);		#
+	&pxor		($Xi,$T2);		#
+}
+
+&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,$Xi);
+
+	&movdqu		(&QWP(0,$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		($T3,&QWP(0,$const));
+	&movups		($Hkey,&QWP(0,$Htbl));
+	&pshufb		($Xi,$T3);
+
+	&clmul64x64_T2	($Xhi,$Xi,$Hkey);
+	&reduction_alg9	($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,$T3);
+	&pxor		($Xi,$T1);		# Ii+Xi
+
+	&clmul64x64_T2	($Xhn,$Xn,$Hkey);	# H*Ii+1
+	&movups		($Hkey,&QWP(16,$Htbl));	# load H^2
+
+	&lea		($inp,&DWP(32,$inp));	# i+=2
+	&sub		($len,0x20);
+	&jbe		(&label("even_tail"));
+
+&set_label("mod_loop");
+	&clmul64x64_T2	($Xhi,$Xi,$Hkey);	# H^2*(Ii+Xi)
+	&movdqu		($T1,&QWP(0,$inp));	# Ii
+	&movups		($Hkey,&QWP(0,$Htbl));	# load H
+
+	&pxor		($Xi,$Xn);		# (H*Ii+1) + H^2*(Ii+Xi)
+	&pxor		($Xhi,$Xhn);
+
+	&movdqu		($Xn,&QWP(16,$inp));	# Ii+1
+	&pshufb		($T1,$T3);
+	&pshufb		($Xn,$T3);
+
+	&movdqa		($T3,$Xn);		#&clmul64x64_TX	($Xhn,$Xn,$Hkey); H*Ii+1
+	&movdqa		($Xhn,$Xn);
+	 &pxor		($Xhi,$T1);		# "Ii+Xi", consume early
+
+	  &movdqa	($T1,$Xi);		#&reduction_alg9($Xhi,$Xi); 1st phase
+	  &psllq	($Xi,1);
+	  &pxor		($Xi,$T1);		#
+	  &psllq	($Xi,5);		#
+	  &pxor		($Xi,$T1);		#
+	&pclmulqdq	($Xn,$Hkey,0x00);	#######
+	  &psllq	($Xi,57);		#
+	  &movdqa	($T2,$Xi);		#
+	  &pslldq	($Xi,8);
+	  &psrldq	($T2,8);		#	
+	  &pxor		($Xi,$T1);
+	&pshufd		($T1,$T3,0b01001110);
+	  &pxor		($Xhi,$T2);		#
+	&pxor		($T1,$T3);
+	&pshufd		($T3,$Hkey,0b01001110);
+	&pxor		($T3,$Hkey);		#
+
+	&pclmulqdq	($Xhn,$Hkey,0x11);	#######
+	  &movdqa	($T2,$Xi);		# 2nd phase
+	  &psrlq	($Xi,5);
+	  &pxor		($Xi,$T2);		#
+	  &psrlq	($Xi,1);		#
+	  &pxor		($Xi,$T2);		#
+	  &pxor		($T2,$Xhi);
+	  &psrlq	($Xi,1);		#
+	  &pxor		($Xi,$T2);		#
+
+	&pclmulqdq	($T1,$T3,0x00);		#######
+	&movups		($Hkey,&QWP(16,$Htbl));	# load H^2
+	&xorps		($T1,$Xn);		#
+	&xorps		($T1,$Xhn);		#
+
+	&movdqa		($T3,$T1);		#
+	&psrldq		($T1,8);
+	&pslldq		($T3,8);		#
+	&pxor		($Xhn,$T1);
+	&pxor		($Xn,$T3);		#
+	&movdqa		($T3,&QWP(0,$const));
+
+	&lea		($inp,&DWP(32,$inp));
+	&sub		($len,0x20);
+	&ja		(&label("mod_loop"));
+
+&set_label("even_tail");
+	&clmul64x64_T2	($Xhi,$Xi,$Hkey);	# H^2*(Ii+Xi)
+
+	&pxor		($Xi,$Xn);		# (H*Ii+1) + H^2*(Ii+Xi)
+	&pxor		($Xhi,$Xhn);
+
+	&reduction_alg9	($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 {		# Algorith 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();
+
+# 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...