[llvm] [VPlan] Fold VPDef into VPRecipeBase (NFC). (PR #174282)

[Florian Hahn via llvm-commits]

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@@ -210,12 +206,12 @@ struct VPSymbolicValue : public VPValue {
 /// A VPValue defined by a recipe that produces one or more values.
 class VPRecipeValue : public VPValue {
   friend class VPValue;
-  friend class VPDef;
-  /// Pointer to the VPDef that defines this VPValue.
-  VPDef *Def;
+  friend class VPRecipeBase;
+  /// Pointer to the VPRecipeBase that defines this VPValue.
+  VPRecipeBase *Def;
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fhahn wrote:

Yep, restored as much of the original code of VPDef, we just need a helper to VPRecipeValue ot check if `Def == this`, before VPRecipeBase is defined.

https://github.com/llvm/llvm-project/pull/174282