[llvm] [VPlan] Optz WidenGEP with single-scalar operands (PR #166740)

[Florian Hahn via llvm-commits]

https://github.com/fhahn commented:

This is different to VPWidenSelect I think, which even with scalar condition produces a vector result for vector operands?

if all operands are single scalar, we should be able to handle this in narrowToSingleScalar, and remove the special handling in the recipe altogether?

https://github.com/llvm/llvm-project/pull/166740