[llvm] [VPlan] Use VPInstruction for VPScalarPHIRecipe. (NFCI) (PR #129767)

[Florian Hahn via llvm-commits]

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@@ -276,6 +276,11 @@ InstructionCost VPRecipeBase::computeCost(ElementCount VF,
                                           VPCostContext &Ctx) const {
   llvm_unreachable("subclasses should implement computeCost");
 }
+bool VPRecipeBase::isPhi() const {
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fhahn wrote:

Added, thanks

https://github.com/llvm/llvm-project/pull/129767