[patch, libfortran] Add AVX-specific matmul

[Jerry DeLisle]

On 11/16/2016 01:30 PM, Thomas Koenig wrote:
> Hello world,
>
> the attached patch adds an AVX-specific version of the matmul
> intrinsic to the Fortran library.  This works by using the target_clones
> attribute.
>
> For testing, I compiled this on powerpc64-unknown-linux-gnu,
> without any ill effects.
>
> Also, a resulting binary reached around 15 GFlops for larger matrices
> on a 3.4 GHz i7-2600 CPU.  I am currently building/regtesting on
> that machine. This can give another 40% speed increase  for large
> matrices on AVX.
>
> OK for trunk?
>

Did you intend to name it avx_matmul and not aux_matmul?

Are the compiler flags for avx handled automatically by the gcc attributes so no 
need to endit the Makefile.am?

Fix the first and if yes to the second question, OK

Jerry