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

[via llvm-commits]

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@@ -205,10 +205,8 @@ bool VPlanVerifier::verifyVPBasicBlock(const VPBasicBlock *VPBB) {
       for (const VPUser *U : V->users()) {
         auto *UI = cast<VPRecipeBase>(U);
         // TODO: check dominance of incoming values for phis properly.
-        if (!UI ||
-            isa<VPHeaderPHIRecipe, VPWidenPHIRecipe, VPPredInstPHIRecipe>(UI) ||
-            (isa<VPIRInstruction>(UI) &&
-             isa<PHINode>(cast<VPIRInstruction>(UI)->getInstruction())))
+        if (!UI || isa<VPHeaderPHIRecipe, VPWidenPHIRecipe, VPPredInstPHIRecipe,
+                       VPIRPhi>(UI))
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ayalz wrote:

Nice!
Independently: drop `!UI`? Probably a remanent of VPLiveOut, but even then should dyn_cast. Could the cast be dropped altogether (or postponed), checking `if (isa<VPHeaderPHIRecipe, VPWidenPHIRecipe, VPPredInstPHIRecipe, VPIRPhi>(U))`?

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