[llvm] [VPlan] Manage instruction medata in VPlan. (PR #135272)

[via llvm-commits]

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@@ -1190,28 +1190,55 @@ struct VPIRPhi : public VPIRInstruction {
 #endif
 };
 
+using MDArrayRef = ArrayRef<std::pair<unsigned, MDNode *>>;
+
+/// Helper to manage IR metadata for recipes. It filters out metadata that
+/// cannot be proagated.
+class VPWithIRMetadata {
+  SmallVector<std::pair<unsigned, MDNode *>> Metadata;
+
+protected:
+  VPWithIRMetadata() {}
+  VPWithIRMetadata(MDArrayRef Metadata) : Metadata(Metadata) {}
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ayalz wrote:

Could alternatively call addMetadata(), to emphasize it is practically folding this call into the constructor.

https://github.com/llvm/llvm-project/pull/135272