[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:

Thoughts about reducing the O(|Metadata|*|Other.Metadata|) complexity here? Perhaps working with a temporary copy of Other.Metadata and erasing from it every element that is matched, which would work better if both Metadata and Other.Metadata are scanned in reverse, for the common case(?) where they are equal?

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