[llvm] [LoopUnroll] Penalize interior control flow (PR #67137)

[Florian Hahn via llvm-commits]

https://github.com/fhahn commented:

Do you have any data on how widespread the impact of this is ?

Penalizing loops with internal control flow makes sense to me in general, unless unrolling allows the branches to be folded. Should this be integrated with `UnrolledInstAnalyzer`? I haven't looked at that in a while though so I am not sure if it actually can correctly estimate such things.

https://github.com/llvm/llvm-project/pull/67137