[llvm] [VPlan] Introduce CSE pass (PR #151872)

[Ramkumar Ramachandra via llvm-commits]

artagnon wrote:

@akuegel Thanks for the report. We realized this problem, and it should be fixed when https://github.com/llvm/llvm-project/pull/156699 lands.

https://github.com/llvm/llvm-project/pull/151872