[llvm] [VPlan] Add specialized VPValue subclasses for different types (NFC) (PR #172758)

[Florian Hahn via llvm-commits]

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@@ -4617,10 +4619,11 @@ void VPlanTransforms::materializeVectorTripCount(VPlan &Plan,
                                                  bool TailByMasking,
                                                  bool RequiresScalarEpilogue) {
   VPValue &VectorTC = Plan.getVectorTripCount();
-  assert(VectorTC.isLiveIn() && "vector-trip-count must be a live-in");
+  assert(isa<VPSymbolicValue>(VectorTC) &&
+         "vector-trip-count must be a live-in");
   // There's nothing to do if there are no users of the vector trip count or its
   // IR value has already been set.
-  if (VectorTC.getNumUsers() == 0 || VectorTC.getLiveInIRValue())
+  if (VectorTC.getNumUsers() == 0 || VectorTC.getUnderlyingValue())
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fhahn wrote:

agreed, but should probably be added together with a mechanism to enforce get* are not queried after materialization?

https://github.com/llvm/llvm-project/pull/172758