[llvm] [LegalizeTypes] Handle non byte-sized elt types when splitting INSERT/EXTRACT_VECTOR_ELT (PR #93357)

[Björn Pettersson via llvm-commits]

bjope wrote:

> > A target could just promote the input vector elements itself if that is feasible when doing CustomLowerNode the first time.
> 
> For non-MVT types, I don't think there's any way for a target to request custom lowering. At least, not using setOperationAction.

Right. CustomLowerNode would just bail out early for such types. I did not consider that, so thanks for enlightening me.
I'll take another look at your proposal related to "construct an EXTRACT_VECTOR_ELT with the promoted vector type".


https://github.com/llvm/llvm-project/pull/93357