[llvm] [VPlan] Add new VPIRPhi overlay for VPIRInsts wrapping phi nodes (NFC). (PR #129387)

[via llvm-commits]

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@@ -1033,16 +1033,19 @@ class VPInstruction : public VPRecipeWithIRFlags,
 class VPIRInstruction : public VPRecipeBase {
   Instruction &I;
 
-public:
+protected:
   VPIRInstruction(Instruction &I)
       : VPRecipeBase(VPDef::VPIRInstructionSC, ArrayRef<VPValue *>()), I(I) {}
 
+public:
   ~VPIRInstruction() override = default;
 
+  static VPIRInstruction *create(Instruction &I);
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ayalz wrote:

Worth documenting `create()`.

https://github.com/llvm/llvm-project/pull/129387