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

[via llvm-commits]

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@@ -202,7 +202,6 @@ class VPUser {
   /// Subclass identifier (for isa/dyn_cast).
   enum class VPUserID {
     Recipe,
-    LiveOut,
   };
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ayalz wrote:

Perhaps better clean this up for now, to avoid false pretense it is in use, and reintroduce if/when desired (for VF/TC).

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