[llvm] [PredicateInfo] Support existing `PredicateType` by adding `PredicatePHI` when needing introduction of phi nodes (PR #151132)

[Rajveer Singh Bharadwaj via llvm-commits]

Rajveer100 wrote:

After debugging under lldb and looking further, I understood the issue.

Re-implementing it :)

https://github.com/llvm/llvm-project/pull/151132