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

[Luke Lau via llvm-commits]

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@@ -80,8 +80,8 @@ bool VPlanVerifier::verifyPhiRecipes(const VPBasicBlock *VPBB) {
       NumActiveLaneMaskPhiRecipes++;
 
     if (IsHeaderVPBB && !isa<VPHeaderPHIRecipe, VPWidenPHIRecipe>(*RecipeI) &&
-        !isa<VPInstruction>(*RecipeI) &&
-        cast<VPInstruction>(RecipeI)->getOpcode() == Instruction::PHI) {
+        !(isa<VPInstruction>(*RecipeI) &&
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lukel97 wrote:

I think a VPIRPhi, i.e a VPIRInstruction with a PHI opcode should also be caught by this, I've added a test case for it in c170996dca9e193166cba01c539c426a30d6c10f

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