[llvm] [SSAUpdater][NFC] Limit search for matching phi-node (PR #195744)

[Valery Pykhtin via llvm-commits]

vpykhtin wrote:

> SSAUpdater is being called by StructurizeCFG.

I would replace the rest of them with SSAUpdaterBulk class and use EliminateDuplicatePHINodes on the large number of phis (meaning that set implementation would be used)

Similar to https://github.com/llvm/llvm-project/pull/135181 



https://github.com/llvm/llvm-project/pull/195744