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[Bug tree-optimization/51499] vectorizer missing simple case


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51499

--- Comment #9 from Ira Rosen <irar at il dot ibm.com> 2011-12-12 11:13:24 UTC ---
(In reply to comment #7)
> 
> In some cases it might be necessary but not here:
> 
>  sum1+=a;
>  sum2+=a;
> 
> gives exactly the same result as
> 
>  (sum1, sum2) += (a, a);
> 

So, you are suggesting to remove the need in flag_associative_math for fp for
cases when a reduction computation is already unrolled by the vectorization
factor. Sounds reasonable to me.


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