[llvm] [VPlan] Implement printing VPIRMetadata. (PR #168385)

[David Sherwood via llvm-commits]

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@@ -1706,6 +1711,28 @@ void VPIRMetadata::intersect(const VPIRMetadata &Other) {
   Metadata = std::move(MetadataIntersection);
 }
 
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
+void VPIRMetadata::print(raw_ostream &O, const VPlan *Plan) const {
+  if (Metadata.empty() || !Plan)
+    return;
+
+  const Module &M = Plan->getModule();
+  SmallVector<StringRef, 8> MDNames;
+  M.getContext().getMDKindNames(MDNames);
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david-arm wrote:

Isn't this quite an expensive operation? Would be great if there was a way to only do this once, although I realise that might be tricky.

https://github.com/llvm/llvm-project/pull/168385