[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:

> Hmm, maybe we can improve this by restructuring how we manage VPMemoryRecipe, but may be best done independently?

Agreed, better fix the "let widen load recipes be single def recipes" first? Perhaps by turning VPWidenMemoryRecipe into VPWidenMemoryAccessors (as in VPPhiAccessors), so that widen loads inherit from it and from SingleDefRecipe, and widen stores inherit from it and from recipe base?

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