[llvm] [LV] Use scalar CMP for active-lane-mask with scalar VF (PR #83902)

[via llvm-commits]

dyung wrote:

Hi @mcinally, the test you added llvm/test/Transforms/LoopVectorize/pr73894.ll seems to be failing on several build bots. Can you take a look and revert if you need time to investigate?

- https://lab.llvm.org/buildbot/#/builders/164/builds/49969
- https://lab.llvm.org/buildbot/#/builders/258/builds/14951
- https://lab.llvm.org/buildbot/#/builders/91/builds/23531
- https://lab.llvm.org/buildbot/#/builders/139/builds/60881
- https://lab.llvm.org/buildbot/#/builders/216/builds/35571
- https://lab.llvm.org/buildbot/#/builders/234/builds/20405
- https://lab.llvm.org/buildbot/#/builders/232/builds/20405
- https://lab.llvm.org/buildbot/#/builders/235/builds/6005
- https://lab.llvm.org/buildbot/#/builders/259/builds/807

https://github.com/llvm/llvm-project/pull/83902