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    Code generation in LZ decoder / Branchless LZ77 Decoder

    There's another post in cbloom blog: http://cbloomrants.blogspot.com/2010...7-decoder.html
    Which reminded me about "D2CT" discussion here: http://encode.su/threads/550-Ultra-f...ll=1#post11005
    And this time I even made an actual implementation to test it, but nobody likes it :)

    http://nishi.dreamhosters.com/u/lzcodegen_v0.rar

    clocks are cpu clocks from rdtsc.
    first result is from 2.cpp, with a plain decoding loop,
    and second is the result with code generation
    (generation+execution)
    Note that IntelC replaced the cpy() with its crazy memcpy
    function call, which works faster with SSE2 or whatever it uses,
    but it doesn't really count because the same tricks can be
    used in generated code too.

    [ MSC ]
    clock=55799840
    clock=42811688+5514896=48326584

    [ gcc450 ]
    clock=53975928
    clock=43155400+5571568=48726968

    [ IC111 ]
    clock=39331688
    clock=43025976+5640504=48666480

  2. Thanks:

    encode (31st May 2017)

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