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

[Florian Hahn via llvm-commits]

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@@ -197,6 +173,52 @@ class LLVM_ABI_FOR_TEST VPValue {
 LLVM_ABI_FOR_TEST raw_ostream &operator<<(raw_ostream &OS,
                                           const VPRecipeBase &R);
 
+/// A VPValue representing a live-in from the input IR. It wraps an underlying
+/// IR Value.
+struct VPLiveIn : public VPValue {
+  VPLiveIn(Value *UV) : VPValue(VPVLiveInSC, UV, nullptr) {
+    assert(UV && "VPLiveIn requires an underlying IR value");
+  }
+
+  /// Returns the underlying IR value.
+  Value *getValue() const { return getUnderlyingValue(); }
+
+  /// Returns the type of the underlying IR value.
+  Type *getType() const;
+
+  static bool classof(const VPValue *V) {
+    return V->getVPValueID() == VPVLiveInSC;
+  }
+};
+
+/// A symbolic live-in VPValue, used for values like vector trip count, VF, and
+/// VFxUF.
+struct VPSymbolicValue : public VPValue {
+  VPSymbolicValue() : VPValue(VPVSymbolicSC, nullptr, nullptr) {}
+
+  static bool classof(const VPValue *V) {
+    return V->getVPValueID() == VPVSymbolicSC;
+  }
+};
+
+/// A VPValue defined by a recipe that produces multiple values.
+class VPDefValue : public VPValue {
+  friend class VPValue;
+  friend class VPDef;
+  /// Pointer to the VPDef that defines this VPValue. If it is nullptr, the
+  /// VPValue is not defined by any recipe modeled in VPlan.
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fhahn wrote:

removed stale, leftover comment, thanks

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