[PATCH] Convert a vselect into a concat_vector if possible

[Filipe Cabecinhas]

Thanks, I didn't remember check-dag. Btw, if we use check-dag, we wouldn't
need the %xmm{{[01]}} regex either! unless I'm looking at it wrong.

I'll commit later today.

Thank you,

Filipe

http://reviews.llvm.org/D3916