[llvm] [LLVM][Transforms] Correct LoopSimplify unique block placement. (PR #105538)

[Nikita Popov via llvm-commits]

nikic wrote:

I don't think we have any fully reliable (and efficient) way to find the "last" block. We have block numbers nowadays, but those also don't have to match block order.

https://github.com/llvm/llvm-project/pull/105538