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#!/usr/bin/env perl |
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# |
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# ==================================================================== |
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# Written by Andy Polyakov <appro@openssl.org> for the OpenSSL |
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# project. The module is, however, dual licensed under OpenSSL and |
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# CRYPTOGAMS licenses depending on where you obtain it. For further |
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# details see http://www.openssl.org/~appro/cryptogams/. |
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# ==================================================================== |
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# |
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# March, May, June 2010 |
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# |
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# The module implements "4-bit" GCM GHASH function and underlying |
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# single multiplication operation in GF(2^128). "4-bit" means that it |
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# uses 256 bytes per-key table [+64/128 bytes fixed table]. It has two |
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# code paths: vanilla x86 and vanilla MMX. Former will be executed on |
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# 486 and Pentium, latter on all others. MMX GHASH features so called |
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# "528B" variant of "4-bit" method utilizing additional 256+16 bytes |
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# of per-key storage [+512 bytes shared table]. Performance results |
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# are for streamed GHASH subroutine and are expressed in cycles per |
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# processed byte, less is better: |
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# |
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# gcc 2.95.3(*) MMX assembler x86 assembler |
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# |
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# Pentium 105/111(**) - 50 |
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# PIII 68 /75 12.2 24 |
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# P4 125/125 17.8 84(***) |
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# Opteron 66 /70 10.1 30 |
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# Core2 54 /67 8.4 18 |
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# |
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# (*) gcc 3.4.x was observed to generate few percent slower code, |
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# which is one of reasons why 2.95.3 results were chosen, |
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# another reason is lack of 3.4.x results for older CPUs; |
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# comparison with MMX results is not completely fair, because C |
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# results are for vanilla "256B" implementation, while |
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# assembler results are for "528B";-) |
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# (**) second number is result for code compiled with -fPIC flag, |
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# which is actually more relevant, because assembler code is |
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# position-independent; |
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# (***) see comment in non-MMX routine for further details; |
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# |
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# To summarize, it's >2-5 times faster than gcc-generated code. To |
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# anchor it to something else SHA1 assembler processes one byte in |
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# 11-13 cycles on contemporary x86 cores. As for choice of MMX in |
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# particular, see comment at the end of the file... |
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# May 2010 |
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# |
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# Add PCLMULQDQ version performing at 2.10 cycles per processed byte. |
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# The question is how close is it to theoretical limit? The pclmulqdq |
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# instruction latency appears to be 14 cycles and there can't be more |
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# than 2 of them executing at any given time. This means that single |
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# Karatsuba multiplication would take 28 cycles *plus* few cycles for |
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# pre- and post-processing. Then multiplication has to be followed by |
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# modulo-reduction. Given that aggregated reduction method [see |
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# "Carry-less Multiplication and Its Usage for Computing the GCM Mode" |
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# white paper by Intel] allows you to perform reduction only once in |
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# a while we can assume that asymptotic performance can be estimated |
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# as (28+Tmod/Naggr)/16, where Tmod is time to perform reduction |
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# and Naggr is the aggregation factor. |
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# |
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# Before we proceed to this implementation let's have closer look at |
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# the best-performing code suggested by Intel in their white paper. |
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# By tracing inter-register dependencies Tmod is estimated as ~19 |
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# cycles and Naggr chosen by Intel is 4, resulting in 2.05 cycles per |
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# processed byte. As implied, this is quite optimistic estimate, |
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# because it does not account for Karatsuba pre- and post-processing, |
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# which for a single multiplication is ~5 cycles. Unfortunately Intel |
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# does not provide performance data for GHASH alone. But benchmarking |
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# AES_GCM_encrypt ripped out of Fig. 15 of the white paper with aadt |
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# alone resulted in 2.46 cycles per byte of out 16KB buffer. Note that |
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# the result accounts even for pre-computing of degrees of the hash |
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# key H, but its portion is negligible at 16KB buffer size. |
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# |
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# Moving on to the implementation in question. Tmod is estimated as |
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# ~13 cycles and Naggr is 2, giving asymptotic performance of ... |
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# 2.16. How is it possible that measured performance is better than |
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# optimistic theoretical estimate? There is one thing Intel failed |
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# to recognize. By serializing GHASH with CTR in same subroutine |
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# former's performance is really limited to above (Tmul + Tmod/Naggr) |
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# equation. But if GHASH procedure is detached, the modulo-reduction |
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# can be interleaved with Naggr-1 multiplications at instruction level |
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# and under ideal conditions even disappear from the equation. So that |
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# optimistic theoretical estimate for this implementation is ... |
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# 28/16=1.75, and not 2.16. Well, it's probably way too optimistic, |
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# at least for such small Naggr. I'd argue that (28+Tproc/Naggr), |
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# where Tproc is time required for Karatsuba pre- and post-processing, |
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# is more realistic estimate. In this case it gives ... 1.91 cycles. |
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# Or in other words, depending on how well we can interleave reduction |
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# and one of the two multiplications the performance should be betwen |
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# 1.91 and 2.16. As already mentioned, this implementation processes |
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# one byte out of 8KB buffer in 2.10 cycles, while x86_64 counterpart |
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# - in 2.02. x86_64 performance is better, because larger register |
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# bank allows to interleave reduction and multiplication better. |
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# |
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# Does it make sense to increase Naggr? To start with it's virtually |
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# impossible in 32-bit mode, because of limited register bank |
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# capacity. Otherwise improvement has to be weighed agiainst slower |
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# setup, as well as code size and complexity increase. As even |
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# optimistic estimate doesn't promise 30% performance improvement, |
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# there are currently no plans to increase Naggr. |
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# |
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# Special thanks to David Woodhouse <dwmw2@infradead.org> for |
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# providing access to a Westmere-based system on behalf of Intel |
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# Open Source Technology Centre. |
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# January 2010 |
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# |
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# Tweaked to optimize transitions between integer and FP operations |
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# on same XMM register, PCLMULQDQ subroutine was measured to process |
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# one byte in 2.07 cycles on Sandy Bridge, and in 2.12 - on Westmere. |
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# The minor regression on Westmere is outweighed by ~15% improvement |
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# on Sandy Bridge. Strangely enough attempt to modify 64-bit code in |
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# similar manner resulted in almost 20% degradation on Sandy Bridge, |
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# where original 64-bit code processes one byte in 1.95 cycles. |
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$0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1; |
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push(@INC,"${dir}","${dir}../../perlasm"); |
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require "x86asm.pl"; |
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&asm_init($ARGV[0],"ghash-x86.pl",$x86only = $ARGV[$#ARGV] eq "386"); |
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$sse2=0; |
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for (@ARGV) { $sse2=1 if (/-DOPENSSL_IA32_SSE2/); } |
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($Zhh,$Zhl,$Zlh,$Zll) = ("ebp","edx","ecx","ebx"); |
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$inp = "edi"; |
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$Htbl = "esi"; |
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$unroll = 0; # Affects x86 loop. Folded loop performs ~7% worse |
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# than unrolled, which has to be weighted against |
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# 2.5x x86-specific code size reduction. |
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sub x86_loop { |
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my $off = shift; |
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my $rem = "eax"; |
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&mov ($Zhh,&DWP(4,$Htbl,$Zll)); |
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&mov ($Zhl,&DWP(0,$Htbl,$Zll)); |
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&mov ($Zlh,&DWP(12,$Htbl,$Zll)); |
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&mov ($Zll,&DWP(8,$Htbl,$Zll)); |
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&xor ($rem,$rem); # avoid partial register stalls on PIII |
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# shrd practically kills P4, 2.5x deterioration, but P4 has |
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# MMX code-path to execute. shrd runs tad faster [than twice |
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# the shifts, move's and or's] on pre-MMX Pentium (as well as |
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# PIII and Core2), *but* minimizes code size, spares register |
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# and thus allows to fold the loop... |
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if (!$unroll) { |
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my $cnt = $inp; |
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&mov ($cnt,15); |
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&jmp (&label("x86_loop")); |
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&set_label("x86_loop",16); |
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for($i=1;$i<=2;$i++) { |
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&mov (&LB($rem),&LB($Zll)); |
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&shrd ($Zll,$Zlh,4); |
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&and (&LB($rem),0xf); |
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&shrd ($Zlh,$Zhl,4); |
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&shrd ($Zhl,$Zhh,4); |
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&shr ($Zhh,4); |
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&xor ($Zhh,&DWP($off+16,"esp",$rem,4)); |
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&mov (&LB($rem),&BP($off,"esp",$cnt)); |
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if ($i&1) { |
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&and (&LB($rem),0xf0); |
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} else { |
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&shl (&LB($rem),4); |
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} |
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&xor ($Zll,&DWP(8,$Htbl,$rem)); |
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&xor ($Zlh,&DWP(12,$Htbl,$rem)); |
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&xor ($Zhl,&DWP(0,$Htbl,$rem)); |
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&xor ($Zhh,&DWP(4,$Htbl,$rem)); |
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if ($i&1) { |
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&dec ($cnt); |
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&js (&label("x86_break")); |
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} else { |
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&jmp (&label("x86_loop")); |
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} |
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} |
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&set_label("x86_break",16); |
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} else { |
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for($i=1;$i<32;$i++) { |
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&comment($i); |
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&mov (&LB($rem),&LB($Zll)); |
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&shrd ($Zll,$Zlh,4); |
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&and (&LB($rem),0xf); |
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&shrd ($Zlh,$Zhl,4); |
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&shrd ($Zhl,$Zhh,4); |
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&shr ($Zhh,4); |
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&xor ($Zhh,&DWP($off+16,"esp",$rem,4)); |
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if ($i&1) { |
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&mov (&LB($rem),&BP($off+15-($i>>1),"esp")); |
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&and (&LB($rem),0xf0); |
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} else { |
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&mov (&LB($rem),&BP($off+15-($i>>1),"esp")); |
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&shl (&LB($rem),4); |
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} |
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&xor ($Zll,&DWP(8,$Htbl,$rem)); |
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&xor ($Zlh,&DWP(12,$Htbl,$rem)); |
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&xor ($Zhl,&DWP(0,$Htbl,$rem)); |
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&xor ($Zhh,&DWP(4,$Htbl,$rem)); |
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} |
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} |
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&bswap ($Zll); |
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&bswap ($Zlh); |
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&bswap ($Zhl); |
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if (!$x86only) { |
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&bswap ($Zhh); |
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} else { |
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&mov ("eax",$Zhh); |
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&bswap ("eax"); |
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&mov ($Zhh,"eax"); |
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} |
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} |
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if ($unroll) { |
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&function_begin_B("_x86_gmult_4bit_inner"); |
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&x86_loop(4); |
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&ret (); |
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&function_end_B("_x86_gmult_4bit_inner"); |
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} |
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sub deposit_rem_4bit { |
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my $bias = shift; |
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&mov (&DWP($bias+0, "esp"),0x0000<<16); |
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&mov (&DWP($bias+4, "esp"),0x1C20<<16); |
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&mov (&DWP($bias+8, "esp"),0x3840<<16); |
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&mov (&DWP($bias+12,"esp"),0x2460<<16); |
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&mov (&DWP($bias+16,"esp"),0x7080<<16); |
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&mov (&DWP($bias+20,"esp"),0x6CA0<<16); |
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&mov (&DWP($bias+24,"esp"),0x48C0<<16); |
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&mov (&DWP($bias+28,"esp"),0x54E0<<16); |
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&mov (&DWP($bias+32,"esp"),0xE100<<16); |
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&mov (&DWP($bias+36,"esp"),0xFD20<<16); |
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&mov (&DWP($bias+40,"esp"),0xD940<<16); |
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&mov (&DWP($bias+44,"esp"),0xC560<<16); |
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&mov (&DWP($bias+48,"esp"),0x9180<<16); |
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&mov (&DWP($bias+52,"esp"),0x8DA0<<16); |
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&mov (&DWP($bias+56,"esp"),0xA9C0<<16); |
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&mov (&DWP($bias+60,"esp"),0xB5E0<<16); |
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} |
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$suffix = $x86only ? "" : "_x86"; |
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&function_begin("gcm_gmult_4bit".$suffix); |
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&stack_push(16+4+1); # +1 for stack alignment |
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&mov ($inp,&wparam(0)); # load Xi |
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&mov ($Htbl,&wparam(1)); # load Htable |
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&mov ($Zhh,&DWP(0,$inp)); # load Xi[16] |
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&mov ($Zhl,&DWP(4,$inp)); |
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&mov ($Zlh,&DWP(8,$inp)); |
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&mov ($Zll,&DWP(12,$inp)); |
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&deposit_rem_4bit(16); |
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&mov (&DWP(0,"esp"),$Zhh); # copy Xi[16] on stack |
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&mov (&DWP(4,"esp"),$Zhl); |
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&mov (&DWP(8,"esp"),$Zlh); |
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&mov (&DWP(12,"esp"),$Zll); |
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&shr ($Zll,20); |
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&and ($Zll,0xf0); |
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if ($unroll) { |
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&call ("_x86_gmult_4bit_inner"); |
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} else { |
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&x86_loop(0); |
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&mov ($inp,&wparam(0)); |
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} |
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&mov (&DWP(12,$inp),$Zll); |
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&mov (&DWP(8,$inp),$Zlh); |
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&mov (&DWP(4,$inp),$Zhl); |
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&mov (&DWP(0,$inp),$Zhh); |
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&stack_pop(16+4+1); |
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&function_end("gcm_gmult_4bit".$suffix); |
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&function_begin("gcm_ghash_4bit".$suffix); |
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&stack_push(16+4+1); # +1 for 64-bit alignment |
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&mov ($Zll,&wparam(0)); # load Xi |
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&mov ($Htbl,&wparam(1)); # load Htable |
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&mov ($inp,&wparam(2)); # load in |
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&mov ("ecx",&wparam(3)); # load len |
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&add ("ecx",$inp); |
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&mov (&wparam(3),"ecx"); |
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&mov ($Zhh,&DWP(0,$Zll)); # load Xi[16] |
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&mov ($Zhl,&DWP(4,$Zll)); |
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&mov ($Zlh,&DWP(8,$Zll)); |
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&mov ($Zll,&DWP(12,$Zll)); |
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&deposit_rem_4bit(16); |
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&set_label("x86_outer_loop",16); |
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&xor ($Zll,&DWP(12,$inp)); # xor with input |
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&xor ($Zlh,&DWP(8,$inp)); |
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&xor ($Zhl,&DWP(4,$inp)); |
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&xor ($Zhh,&DWP(0,$inp)); |
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&mov (&DWP(12,"esp"),$Zll); # dump it on stack |
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&mov (&DWP(8,"esp"),$Zlh); |
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&mov (&DWP(4,"esp"),$Zhl); |
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&mov (&DWP(0,"esp"),$Zhh); |
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&shr ($Zll,20); |
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&and ($Zll,0xf0); |
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if ($unroll) { |
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&call ("_x86_gmult_4bit_inner"); |
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} else { |
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&x86_loop(0); |
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&mov ($inp,&wparam(2)); |
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} |
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&lea ($inp,&DWP(16,$inp)); |
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&cmp ($inp,&wparam(3)); |
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&mov (&wparam(2),$inp) if (!$unroll); |
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&jb (&label("x86_outer_loop")); |
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&mov ($inp,&wparam(0)); # load Xi |
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&mov (&DWP(12,$inp),$Zll); |
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&mov (&DWP(8,$inp),$Zlh); |
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&mov (&DWP(4,$inp),$Zhl); |
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&mov (&DWP(0,$inp),$Zhh); |
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&stack_pop(16+4+1); |
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&function_end("gcm_ghash_4bit".$suffix); |
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if (!$x86only) {{{ |
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&static_label("rem_4bit"); |
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if (!$sse2) {{ # pure-MMX "May" version... |
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$S=12; # shift factor for rem_4bit |
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&function_begin_B("_mmx_gmult_4bit_inner"); |
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# MMX version performs 3.5 times better on P4 (see comment in non-MMX |
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# routine for further details), 100% better on Opteron, ~70% better |
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# on Core2 and PIII... In other words effort is considered to be well |
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# spent... Since initial release the loop was unrolled in order to |
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# "liberate" register previously used as loop counter. Instead it's |
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# used to optimize critical path in 'Z.hi ^= rem_4bit[Z.lo&0xf]'. |
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# The path involves move of Z.lo from MMX to integer register, |
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# effective address calculation and finally merge of value to Z.hi. |
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# Reference to rem_4bit is scheduled so late that I had to >>4 |
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# rem_4bit elements. This resulted in 20-45% procent improvement |
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# on contemporary µ-archs. |
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{ |
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my $cnt; |
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my $rem_4bit = "eax"; |
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my @rem = ($Zhh,$Zll); |
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my $nhi = $Zhl; |
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my $nlo = $Zlh; |
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my ($Zlo,$Zhi) = ("mm0","mm1"); |
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my $tmp = "mm2"; |
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&xor ($nlo,$nlo); # avoid partial register stalls on PIII |
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&mov ($nhi,$Zll); |
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&mov (&LB($nlo),&LB($nhi)); |
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&shl (&LB($nlo),4); |
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&and ($nhi,0xf0); |
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&movq ($Zlo,&QWP(8,$Htbl,$nlo)); |
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&movq ($Zhi,&QWP(0,$Htbl,$nlo)); |
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&movd ($rem[0],$Zlo); |
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for ($cnt=28;$cnt>=-2;$cnt--) { |
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my $odd = $cnt&1; |
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my $nix = $odd ? $nlo : $nhi; |
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&shl (&LB($nlo),4) if ($odd); |
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&psrlq ($Zlo,4); |
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&movq ($tmp,$Zhi); |
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&psrlq ($Zhi,4); |
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&pxor ($Zlo,&QWP(8,$Htbl,$nix)); |
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&mov (&LB($nlo),&BP($cnt/2,$inp)) if (!$odd && $cnt>=0); |
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&psllq ($tmp,60); |
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&and ($nhi,0xf0) if ($odd); |
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&pxor ($Zhi,&QWP(0,$rem_4bit,$rem[1],8)) if ($cnt<28); |
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&and ($rem[0],0xf); |
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&pxor ($Zhi,&QWP(0,$Htbl,$nix)); |
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&mov ($nhi,$nlo) if (!$odd && $cnt>=0); |
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&movd ($rem[1],$Zlo); |
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&pxor ($Zlo,$tmp); |
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push (@rem,shift(@rem)); # "rotate" registers |
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} |
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&mov ($inp,&DWP(4,$rem_4bit,$rem[1],8)); # last rem_4bit[rem] |
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&psrlq ($Zlo,32); # lower part of Zlo is already there |
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&movd ($Zhl,$Zhi); |
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&psrlq ($Zhi,32); |
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&movd ($Zlh,$Zlo); |
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&movd ($Zhh,$Zhi); |
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&shl ($inp,4); # compensate for rem_4bit[i] being >>4 |
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&bswap ($Zll); |
|
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&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],$red[2]); |
|
|
|
|
|
# Just like in "May" verson modulo-schedule for critical path in |
|
|
# 'Z.hi ^= rem_8bit[Z.lo&0xff^((u8)H[nhi]<<4)]<<48'. Final 'pxor' |
|
|
# is scheduled so late that rem_8bit[] has to be shifted *right* |
|
|
# by 16, which is why last argument to pinsrw is 2, which |
|
|
# corresponds to <<32=<<48>>16... |
|
|
for ($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); |
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|
|
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|
####### |
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&movdqa ($T3,&QWP(0,$const)); |
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&movdqu ($T1,&QWP(0,$inp)); # Ii |
|
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&movdqu ($Xn,&QWP(16,$inp)); # Ii+1 |
|
|
&pshufb ($T1,$T3); |
|
|
&pshufb ($Xn,$T3); |
|
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&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 |
|
|
}} # $sse2 |
|
|
|
|
|
&set_label("rem_4bit",64); |
|
|
&data_word(0,0x0000<<$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); |
|
|
&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...
|
|
|
|