[Bug rtl-optimization/56766] Fails to combine (vec_select (vec_concat ...)) to (vec_merge ...)

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56766

--- Comment #20 from Segher Boessenkool <segher at gcc dot gnu.org> ---
That patch is similar to what all other backends do for similar
situations, yes.  There is no nicer way to do things as far as I
know.