[llvm] [VPlan] Fix header phi VPInstruction verification. NFC (PR #151472)

[Ramkumar Ramachandra via llvm-commits]

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@@ -287,6 +287,38 @@ TEST_F(VPVerifierTest, BlockOutsideRegionWithParent) {
 #endif
 }
 
+TEST_F(VPVerifierTest, NonHeaderPHIInHeader) {
+  VPlan &Plan = getPlan();
+  VPValue *Zero = Plan.getOrAddLiveIn(ConstantInt::get(Type::getInt32Ty(C), 0));
+  auto *CanIV = new VPCanonicalIVPHIRecipe(Zero, {});
+  VPInstruction *BranchOnCond =
+      new VPInstruction(VPInstruction::BranchOnCond, {CanIV});
+
+  VPBasicBlock *VPBB1 = Plan.getEntry();
+  VPBasicBlock *VPBB2 = Plan.createVPBasicBlock("");
+
+  VPBB2->appendRecipe(CanIV);
+
+  PHINode *PHINode = PHINode::Create(Type::getInt32Ty(C), 2);
+  VPIRPhi *IRPhi = new VPIRPhi(*PHINode);
+  VPBB2->appendRecipe(IRPhi);
+  VPBB2->appendRecipe(BranchOnCond);
+
+  VPRegionBlock *R1 = Plan.createVPRegionBlock(VPBB2, VPBB2, "R1");
+  VPBlockUtils::connectBlocks(VPBB1, R1);
+  VPBlockUtils::connectBlocks(R1, Plan.getScalarHeader());
+
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artagnon wrote:

Oops, it should be VPBB2, but it looks like the constructor already sets the parent.

https://github.com/llvm/llvm-project/pull/151472