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

[Luke Lau 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("");
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lukel97 wrote:

VPBB2 is the vector header block, so I named it "header"

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