[llvm] [LV] codegen for tail-folded epilogue loop (PR #208764)

[Florian Hahn via llvm-commits]

https://github.com/fhahn commented:

> Hi @fhahn According to your comments here: [#202818 (review)](https://github.com/llvm/llvm-project/pull/202818#pullrequestreview-4503794964) Is this what you mean ?

Yep that was what I had in mind, thank you very much! There's the somewhat recent addition of `VPlan::hasTailFolded`, which can be used to check if the plan has its tail folded. This should help to remove various checks/flags in the patch.

In some cases it looks like the passed flags are not used or may not be needed (left some inline comments)

https://github.com/llvm/llvm-project/pull/208764