[llvm] [VPlan] Expand VPWidenIntOrFpInductionRecipe into separate recipes (PR #118638)

[Luke Lau via llvm-commits]

lukel97 wrote:

> However, it does make more sense to stick with same approach: either emit vp-intrinsics always out of vectorizer or to have a minimal subset + postprocessing pass after vectorizer. Current vision is to do former. By the way, unary and binary evl-recipes are already supported #93854, so it should be fine to use that, right ?

Agreed, that seems like a sensible way forwards. And just to echo what @Mel-Chen and @arcbbb are saying, we can do the EVL-recipe conversion as a separate incremental follow up to #115274 (which hopefully in turn can become a follow up to this PR)

https://github.com/llvm/llvm-project/pull/118638