[llvm] [InstCombine] Support well-defined recurrences in isGuaranteedNotToBeUndefOrPoison (PR #150420)

[David Sherwood via llvm-commits]

david-arm wrote:

> (Looks inappropriate for VT at a glance)

Hi @nikic, is the problem merely about the location of the new function, i.e. ValueTracking.cpp is an inappropriate place? If so, would you be happy with the PR if @c-rhodes simply moves this to another location?

Or are you concerned about calling `canFoldFreezeIntoRecurrence` from `isGuaranteedNotToBeUndefOrPoison` regardless of where it lives?

https://github.com/llvm/llvm-project/pull/150420