[llvm] [VPlan] Use scalar VPPhi instead of VPWidenPHIRecipe in createPlainCFG. (PR #150847)

[Florian Hahn via llvm-commits]

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@@ -1243,8 +1243,20 @@ struct LLVM_ABI_FOR_TEST VPPhi : public VPInstruction, public VPPhiAccessors {
     return R && R->getOpcode() == Instruction::PHI;
   }
 
+  static inline bool classof(const VPValue *V) {
+    auto *VPI = dyn_cast<VPInstruction>(V);
+    return VPI && VPI->getOpcode() == Instruction::PHI;
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fhahn wrote:

Updated to also clean up, thanks

https://github.com/llvm/llvm-project/pull/150847