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

[Florian Hahn 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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fhahn wrote:

Dropped, thanks! Also helps to simplify code in multiple places by replacing dyn_casts with casts

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