[llvm] [VPlan] First step towards VPlan cost modeling (LegacyCM in CostCtx) (PR #92555)

[Florian Hahn via llvm-commits]

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@@ -738,6 +760,10 @@ class VPRecipeBase : public ilist_node_with_parent<VPRecipeBase, VPBasicBlock>,
   /// this VPRecipe, thereby "executing" the VPlan.
   virtual void execute(VPTransformState &State) = 0;
 
+  /// Compute the cost for the recipe. Returns an invalid cost if the recipe
+  /// does not yet implement computing the cost.
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fhahn wrote:

Updated to reflect the fact that the default implementation now returns the cost via the legacy CM, thanks!

https://github.com/llvm/llvm-project/pull/92555