[llvm] [GVN] Invalidate ICF cache when clearing the instructions (PR #68145)

[Nikita Popov via llvm-commits]

https://github.com/nikic requested changes to this pull request.

Clearing ICF as a whole is not the correct way to fix this. It needs to be incrementally invalidated, as other parts of GVN already do. The first step would be to provide a test case for the assertion failure.

https://github.com/llvm/llvm-project/pull/68145