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Re: "unhandled use" in vectorizing a dot product?
Benjamin Redelings I <benjamin_redelings@ncsu.edu> wrote on 02/12/2009
16:35:45:
> Is there a good place on the wiki to add the
> following information, to help newcomers get up to speed?
>
> * -ffast-math is required to vectorize dot products and other sums.
We can add it here:
http://gcc.gnu.org/projects/tree-ssa/vectorization.html.
> * if the loop is optimized out, then there will be no report of its
> vectorizability.
> * (?) this is the ONLY reason that there would be no such report.
> * if a function is inlined into another function, then its
> vectorizability will be reported again, in that function.
> * if all uses of a function are inlined, then there will be no
> "vectorized n loops in function" message.
> * functions are (of course) not analyzed by the vectorizer in the order
> in which they are declared.
These are true for all optimizations.
Ira
>
> I guess this doesn't matter now, but here is the corrected file, for
> reference.
>
> Thanks a lot!
>
> -BenRI
> [attachment "m3s.c" deleted by Ira Rosen/Haifa/IBM]