[llvm] [VPlan] Use VPInstruction for VPScalarPHIRecipe. (NFCI) (PR #129767)

[via llvm-commits]

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@@ -3283,11 +3298,12 @@ void VPWidenPointerInductionRecipe::execute(VPTransformState &State) {
   BasicBlock *VectorPH = State.CFG.getPreheaderBBFor(this);
   PHINode *NewPointerPhi = nullptr;
   if (CurrentPart == 0) {
-    auto *IVR = cast<VPHeaderPHIRecipe>(&getParent()
-                                             ->getPlan()
-                                             ->getVectorLoopRegion()
-                                             ->getEntryBasicBlock()
-                                             ->front());
+    auto *IVR = getParent()
+                    ->getPlan()
+                    ->getVectorLoopRegion()
+                    ->getEntryBasicBlock()
+                    ->front()
+                    .getVPSingleValue();
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ayalz wrote:

Independently: is there a better way to retrieve IVR?

https://github.com/llvm/llvm-project/pull/129767