[vorbis-dev] optimization progress

[Takehiro Tominaga]

Hi all,

>>>>> "S" == Segher Boessenkool <segher at eastsite.nl> writes:

    S> Didn't get the mdct yet; 1024 point mdct is a bit much to
    S> brute-force, and I'm not going to hand-unroll the whole thing
    S> either (the machine- unrolled version produced a 1.5M
    S> executable; understandably, it wasn't very fast. Still waiting
    S> for processors with 1.5M L1 code caches ;-)

I have just made a quick hack on the vorbis's mdct code. NO UNROLLING
is there :).  the decoding speed gain is only 5% on my celeron box.

and the output is not identical. I think this is becuase of floating point
rounding problem, but there may be a bug.

The attached patch is for yesterday's cvs nighty snapshot.
pls your gain and the result.
--- 
Takehiro TOMINAGA // may the source be with you!


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