[llvm] [LV] Avoid redundant SCEVChecks on active lane mask (PR #171605)

[Florian Hahn via llvm-commits]

https://github.com/fhahn commented:

If possible would be good to proceed step-by-step and try to remove overflow checks in a more targeted fashion so it's easier to reason about. 


https://github.com/llvm/llvm-project/pull/171605