[llvm] [VPlan] Fix classof() in VPWiden{Load|Store}Recipe NFC. (PR #119691)

[Elvis Wang via llvm-commits]

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@@ -2966,7 +2966,15 @@ struct VPWidenLoadRecipe final : public VPWidenMemoryRecipe, public VPValue {
                                  getDebugLoc());
   }
 
-  VP_CLASSOF_IMPL(VPDef::VPWidenLoadSC);
+  static inline bool classof(const VPRecipeBase *R) {
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ElvisWang123 wrote:

Yes. But we need to add the derived class's ID to the parent class `classof()` implementation. 
Otherwise `isa<VPWidenLoadRecipe>(VPWidenLoadEVLRecipe)` return `false`.

We can found that there are some similar implementation such as `VPReductionRecipe::classof()` and `VPWidenREcipe::classof()`.

https://github.com/llvm/llvm-project/pull/119691