[llvm] [GVN] Improve processBlock for instruction erasure (PR #131753)

[Nikita Popov via llvm-commits]

https://github.com/nikic commented:

Could you provide more details on the motivation for this change? Is it just to resolve the FIXME or something else?

It looks like the stack-layout-remark.c clang test crashes.

https://github.com/llvm/llvm-project/pull/131753