[llvm] [SimplifyCFG] Consider preds to switch in `simplifyDuplicateSwitchArms` (PR #118955)

[Nikita Popov via llvm-commits]

https://github.com/nikic commented:

Can you please pre-commit the tests and add a test where the transform triggers but does not convert into a select afterwards (only reduces blocks)?

https://github.com/llvm/llvm-project/pull/118955