[llvm] [ValueTracking] Skip incoming values that are the same as the phi in `isGuaranteedNotToBeUndefOrPoison` (PR #130111)

[Nikita Popov via llvm-commits]

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nikic wrote:

These tests look overly complicated. Can we use `freeze %phi` being replaced with `%phi` as the test case?

https://github.com/llvm/llvm-project/pull/130111