[llvm] [LoopInterchange] Enable it by default (PR #124911)

[Nikita Popov via llvm-commits]

nikic wrote:

I don't think there's a need to disable the pass with ThinLTO. Though it's worth noting that with https://github.com/llvm/llvm-project/pull/145503 the pass will only run once per function in post-link optimization, rather than both in pre-link and post-link optimization. So it will probably reduce the impact on ThinLTO.

https://github.com/llvm/llvm-project/pull/124911