[llvm] [MachinePipeliner] Make Recurrence MII More Accurate (PR #105475)

[Ryotaro Kasuga via llvm-commits]

https://github.com/kasuga-fj commented:

Thanks (actually, I found the same problem recently and was trying to fix it, so thanks for the help). The algorithm looks good to me. I left a few minor comments, could you check them out?

https://github.com/llvm/llvm-project/pull/105475