[llvm] [LoopUnroll] Rotate loop to make it countable for runtime unrolling (PR #146540)

[Marek Sedláček via llvm-commits]

mark-sed wrote:

Some people who seem knowledgeable of these parts (worked recently on something here): @fhahn @mtrofin @ssahasra @nikic @MatzeB @HaohaiWen  

https://github.com/llvm/llvm-project/pull/146540