[llvm] [VPlan] Use VPIRMetadata for VPInterleaveRecipe. (PR #153084)

[via llvm-commits]

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@@ -1491,6 +1491,17 @@ void VPIRMetadata::applyMetadata(Instruction &I) const {
     I.setMetadata(Kind, Node);
 }
 
+void VPIRMetadata::intersect(const VPIRMetadata &Other) {
+  SmallVector<std::pair<unsigned, MDNode *>> MetadataUnion;
+  for (const auto &[KindA, MDA] : Metadata) {
+    for (const auto &[KindB, MDB] : Other.Metadata) {
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ayalz wrote:

Ok, deserves a note.
Sure the entries are unsorted, and expected to be few. Thought of retaining SmallVectors but erasing from a copy of Other every matched entry, iterating over both in reverse, aiming to be linear in (the frequent?) case the two metadata are ordered similarly and their intersection is large.

https://github.com/llvm/llvm-project/pull/153084