[llvm] [VPlan] Create resume phis in scalar preheader early. (NFC) (PR #166099)

[Florian Hahn via llvm-commits]

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@@ -346,6 +346,8 @@ TEST_F(VPIRVerifierTest, testVerifyIRPhiInScalarHeaderVPIRBB) {
   Function *F = M.getFunction("f");
   BasicBlock *LoopHeader = F->getEntryBlock().getSingleSuccessor();
   auto Plan = buildVPlan(LoopHeader);
+  VPValue *Zero = Plan->getConstantInt(32, 0);
+  Plan->getScalarHeader()->front().addOperand(Zero);
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fhahn wrote:

The initial plan now already has the operands of the scalar header phis set up correctly, so here we now add anothe operand to trigger a mismatch between #incoming values and #predecessors 

https://github.com/llvm/llvm-project/pull/166099