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From: "burnus at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug fortran/53957] Polyhedron 11 benchmark: MP_PROP_DESIGN twice as long as other compiler
Date: Wed, 18 Jul 2012 14:05:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53957

--- Comment #6 from Tobias Burnus <burnus at gcc dot gnu.org> 2012-07-18 14:04:45 UTC ---
Created attachment 27823
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27823
Draft patch: Change comparison into bool assignment, decrement conditional jump

(In reply to comment #5)
> If you do

>          exit = countm1 == 0;
>          countm1--;
> >        if (exit) goto exit_label;

> it would work for this case.


If I apply the attached patch, I do not see any performance difference on my
AMD Athlon64 x2 4800+ with -Ofast -funroll-loops -march=native. 

real  3m45.711s  3m45.589s  3m44.308s  | 3m45.363s  3m45.328s  3m44.220s
user  3m45.710s  3m45.582s  3m44.274s  | 3m45.282s  3m45.286s  3m44.218s