[llvm] [VPlan] Remove Def pointer from for VPSingleDefRecipes (NFC) (PR #195483)

[via llvm-commits]

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@@ -3568,13 +3569,14 @@ class LLVM_ABI_FOR_TEST VPWidenMemoryRecipe : public VPRecipeBase,
 
 /// A recipe for widening load operations, using the address to load from and an
 /// optional mask.
-struct LLVM_ABI_FOR_TEST VPWidenLoadRecipe final : public VPWidenMemoryRecipe,
-                                                   public VPRecipeValue {
+struct LLVM_ABI_FOR_TEST VPWidenLoadRecipe final
+    : public VPWidenMemoryRecipe,
+      public VPStandaloneRecipeValue {
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ayalz wrote:

Should VPWidenLoad[EVL]Recipe inherit from VPSingleDefValue rather than from VPStandaloneRecipeValue (aka VPMultiDefValue)? The former admittedly does not inherit from VPSingleDefRecipe (due to its inheritance from VPWidenMemoryRecipe, which in turn also serves VPWidenStore[EVL]Recipe that define no value), but when retrieving the recipe that defines a VPSingleDefValue we can check if it isa VPSingleDefValue or a VPWidenLoad[EVL]Recipe?

https://github.com/llvm/llvm-project/pull/195483