[llvm] [LV] Make having flags (FMFs etc) not require inheriting VPSingleDefRecipe (PR #114972)

[Benjamin Maxwell via llvm-commits]

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@@ -803,6 +805,9 @@ class VPRecipeBase : public ilist_node_with_parent<VPRecipeBase, VPBasicBlock>,
   /// Returns the debug location of the recipe.
   DebugLoc getDebugLoc() const { return DL; }
 
+  /// Returns the IR flags for the recipe.
+  virtual VPRecipeIRFlags *getIRFlags() { return nullptr; }
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MacDue wrote:

Not alone, but I've added a `const` overload now. 

https://github.com/llvm/llvm-project/pull/114972