[llvm] [DebugInfo][GVNSink] Fix #77415: GVNSink fails to optimize LLVM IR with debug info (PR #77602)

[Nikita Popov via llvm-commits]

nikic wrote:

I'm not willing to merge any changes to this pass before the non-determinism issue is fixed, so we can actually test things without fear of breaking the build.

https://github.com/llvm/llvm-project/pull/77602