[llvm] [llvm][loop-rotate] Allow forcing loop-rotation (PR #82828)

[Florian Hahn via llvm-commits]

https://github.com/fhahn commented:

Could you add a PhaseOrdering test that shows the impact of the change? Possibly just with the reproducer from https://github.com/llvm/llvm-project/issues/50308

https://github.com/llvm/llvm-project/pull/82828