[llvm] [VPlan] Add VPPhiAccessors to provide interface for phi recipes (NFC) (PR #129388)

[Florian Hahn via llvm-commits]

================
@@ -3069,11 +3069,9 @@ void InnerLoopVectorizer::fixNonInductionPHIs(VPTransformState &State) {
       PHINode *NewPhi = cast<PHINode>(State.get(VPPhi));
       // Make sure the builder has a valid insert point.
       Builder.SetInsertPoint(NewPhi);
-      for (unsigned Idx = 0; Idx < VPPhi->getNumOperands(); ++Idx) {
-        VPValue *Inc = VPPhi->getIncomingValue(Idx);
-        VPBasicBlock *VPBB = VPPhi->getIncomingBlock(Idx);
+
+      for (const auto &[Inc, VPBB] : VPPhi->incoming_values_and_blocks())
----------------
fhahn wrote:

It is a short form of incoming value, while Idx would refer to an Index?

https://github.com/llvm/llvm-project/pull/129388