[PATCH] - Improve widening of 3 element binary vector operations that don't trap

[Nadav Rotem]

Hi Paul, 

This patch looks good, but I am a little worried about denormals.  With this patch we will execute vector operations on garbage at the fourth vector element.  One possible solution would be to mask out the last element. Does that sound right to you ?

Thanks,
Nadav

On Aug 19, 2013, at 8:14 AM, Redmond, Paul <paul.redmond at intel.com> wrote:

> This patch improves the widening of non-div/rem binary vector operations
> 
> - split WidenVecRes_Binary into WidenVecRes_Binary and
> WidenVecRes_BinaryCanTrap
>  - WidenVecRes_BinaryCanTrap preserves the original behaviour for
> operations that can trap
>  - WidenVecRes_Binary simply widens the operation and improves codegen
> for 3 element vectors
>    by allowing widening and promotion on x86 (matches the behaviour of
> unary and ternary
>    operation widening)
> 
> Thanks
> paul
> 
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