[llvm] [LV] Limits the splat operations be hoisted must not be defined by a recipe. (PR #117138)

[Florian Hahn via llvm-commits]

fhahn wrote:

How about adding a VPDominatorTree to VPTransformState, using that to check for dominance? VPlan's CFG shouldn't change during execution, so no need to worry about updates

https://github.com/llvm/llvm-project/pull/117138