[llvm] [VPlan] Introduce scalar loop header in plan, remove VPLiveOut. (PR #109975)

[David Sherwood via llvm-commits]

david-arm wrote:

Also, is there a document somewhere that highlights (even at a high level) some of the refactoring work like this that is planned in the next few months? Just because I'm also actively working in this area. Or if not, is it possible to tag me as a reviewer or subscriber for other patches in this area? Thanks!

https://github.com/llvm/llvm-project/pull/109975