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

[via llvm-commits]

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@@ -1757,7 +1775,7 @@ InstructionCost VPCostContext::getScalarizationOverhead(
   SmallPtrSet<const VPValue *, 4> UniqueOperands;
   SmallVector<Type *> Tys;
   for (auto *Op : Operands) {
-    if (Op->isLiveIn() ||
+    if (isa<VPIRValue>(Op) ||
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ayalz wrote:

Here VPSymbolicValue (with UV) is irrelevant?

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