[MPlayer-dev-eng] [OT] C-code Optimiation Contest

[Felix Buenemann]

On Tuesday 15 July 2003 09:50, Arpi wrote:
> Hi,
>
> > > > > 1. you may only modify multiply_d.[ch] (NUM should stay 512 though)
> > > > > 2. you may change compiler and optims in Makefile
> > > > > 3. precision must stay the same
> > > > > 4. to compare, you should compile the orginal code:
> > > > >     make && copy matrix matrix.org && (./matrix.org >res.org)
> > > > > 5. then later you can compare results via:
> > > > >    make && (./matrix >res.txt) && diff -q res.org res.txt
> > > > >
> > > > > Have fun!
> > > > >
> > > > > Btw. current results by me is 738% of original speed, arpis results
> > > > > are even better, as he included my tips in his alredy optimized
> > > > > code =))))
> > > >
> > > > ok here is my (ok, our:)) contribution:
> > > >
> > > > to get best results (19.628 faster than original) set DIM to 516 in
> > > > the .h
> > >
> > > hmm, only ~20x faster ...
> > > i get ~1000x faster (see attached) :)))
> > >
> > > [...]
> >
> > now you know why we needed you @ LinuxTag, we would have won all coding
> > contests! (That means at least 4 Notebooks =))
> >
> > (michael's code: Cycles: 7423830  1121.179)
> >
> > Btw. what algorithm are you implementing or did you invent it yourself?
>
> he is cheating, his code works only for that data set you pass in the
> sample program (a+b and a*b afair) :)))
> dunno if it was allowed at linuxtag compo...
no it wasn't allowed, as data was changed before comparing the final results.

>
> A'rpi / Astral & ESP-team
>
-- 
Best Regards,
        Atmos
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