[llvm] [InstCombine] Fix select combine with null_pointer_is_valid. (PR #227168)

[Yingwei Zheng via llvm-commits]

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dtcxzyw wrote:

Is `if((HasDereferenceable || GEP->isInBounds()) && !NullPointerIsDefined)` better? Then we don't need to modify the callers.


https://github.com/llvm/llvm-project/pull/227168