[llvm] [VPlan] Optimize resume values of IVs together with other exit values. (PR #174239)

[Florian Hahn via llvm-commits]

https://github.com/fhahn commented:

> The PR no longer seems to be optimising anything, at least I can't see that from the tests. It might be worth re-writing the title and commit message if all this is doing now is simply refactoring?


Thanks, I updated the description. I think the title is still accurate, as it still optimizes all IV live-outs together (both for the scalar resume phis and exit values), instead of doing it separately  as done previously in the removed `updateScalarResumePhis`

https://github.com/llvm/llvm-project/pull/174239