[llvm] [GVN] Handle empty attrs in Expression == (PR #115761)

[via llvm-commits]

ronlieb wrote:

> Does it address the crash reported in [#114545 (comment)](https://github.com/llvm/llvm-project/pull/114545#issuecomment-2465910622)? cc @ronlieb

yes it does, thanks!

https://github.com/llvm/llvm-project/pull/115761