Add 0.9.7 specific comments to RC4 assembler modules.
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@ -1,7 +1,7 @@
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#!/usr/local/bin/perl
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# At some point it became apparent that the original SSLeay RC4
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# assembler implementation performs suboptimal on latest IA-32
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# assembler implementation performs suboptimaly on latest IA-32
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# microarchitectures. After re-tuning performance has changed as
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# following:
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#
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@ -15,10 +15,12 @@
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# In other words code performing further 13% faster on AMD
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# would perform almost 2 times slower on Intel PIII...
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# For reference! This code delivers ~80% of rc4-amd64.pl
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# performance on same Opteron machine.
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# performance on the same Opteron machine.
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# (**) This number requires compressed key schedule set up by
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# RC4_set_key, see commentary section in rc4_skey.c for
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# further details.
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# RC4_set_key and therefore doesn't apply to 0.9.7 [option for
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# compressed key schedule is implemented in 0.9.8 and later,
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# see commentary section in rc4_skey.c for further details].
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#
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# <appro@fy.chalmers.se>
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push(@INC,"perlasm","../../perlasm");
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@ -130,6 +132,8 @@ sub RC4
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&add( $d, 8);
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# detect compressed schedule, see commentary section in rc4_skey.c...
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# in 0.9.7 context ~50 bytes below RC4_CHAR label remain redundant,
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# as compressed key schedule is set up in 0.9.8 and later.
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&cmp(&DWP(256,$d),-1);
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&je(&label("RC4_CHAR"));
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@ -190,7 +194,8 @@ sub RC4
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&jmp(&label("finished"));
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&align(16);
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# this is essentially Intel P4 specific codepath, see rc4_skey.c...
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# this is essentially Intel P4 specific codepath, see rc4_skey.c,
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# and is engaged in 0.9.8 and later context...
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&set_label("RC4_CHAR");
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&lea ($ty,&DWP(0,$in,$ty));
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@ -30,7 +30,9 @@
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# RC4_CHAR. Kind of ironic, huh? As it's apparently impossible to
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# compose blended code, which would perform even within 30% marginal
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# on either AMD and Intel platforms, I implement both cases. See
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# rc4_skey.c for further details...
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# rc4_skey.c for further details... This applies to 0.9.8 and later.
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# In 0.9.7 context RC4_CHAR codepath is never engaged and ~70 bytes
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# of code remain redundant.
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$output=shift;
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@ -18,7 +18,7 @@
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// to input and output streams. Secondly, less obvious, it's possible
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// to pull up some references to elements of the key schedule itself.
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// Fact is that such prior loads are not safe only for "degenerated"
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// key schedule, when all elements equal to the same value, which is
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// key schedule, when some elements equal to the same value, which is
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// never the case [key schedule setup routine makes sure it's not].
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// Furthermore. In order to compress loop body to the minimum, I chose
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// to deploy deposit instruction, which substitutes for the whole
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