[llvm] [InstCombine] Avoid infinite loop when negating phi nodes (PR #104581)

[Nikita Popov via llvm-commits]

https://github.com/nikic approved this pull request.

LGTM

This is fine. Not pushing things across backedges is the usual way to avoid these infinite loops.

https://github.com/llvm/llvm-project/pull/104581