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Re: [i386] Scalar DImode instructions on XMM registers


2015-04-24 13:27 GMT+03:00 Marc Glisse <marc.glisse@inria.fr>:
> On Fri, 24 Apr 2015, Uros Bizjak wrote:
>
>> Please try to generate paradoxical subreg (V2DImode subreg of V1DImode
>> pseudo). IIRC, there is some functionality in the compiler that is
>> able to tell if the highpart of the paradoxical register is zeroed.
>
>
> Those are not currently legal (I tried to change that)
> https://gcc.gnu.org/ml/gcc-patches/2013-03/msg00745.html
> https://gcc.gnu.org/ml/gcc-patches/2014-06/msg00769.html
>
> In this case, a subreg:V2DI of DImode should work.
>
> --
> Marc Glisse

Thank you for you tips! It seems to work, will try and see what it
gives us for i386.

Thanks,
Ilya


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