[llvm] [LoopPeel] Peel to make Phis loop inductions (PR #121104)

[Ryotaro Kasuga via llvm-commits]

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kasuga-fj wrote:

Added two cases where the peeling is not desirable. The current implementation only considers constant increments, so I don't think there are any cases where peeling does not result in IV (there are cases where the variable is originally IV without peeling).

https://github.com/llvm/llvm-project/pull/121104