[PATCH] D40427: [ADT] Introduce Disjoint Set Union structure

[Max Kazantsev via Phabricator via llvm-commits]

mkazantsev added inline comments.


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Comment at: include/llvm/ADT/DisjointSetUnion.h:105
+  // Memorizes calculated ranks of head vertices.
+  DenseMap<T, int> Rank;
+};
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mkazantsev wrote:
> sanjoy wrote:
> > How about just one `DenseMap` that maps `T` instances to a `std::pair<T, int>`?
> That would consume as twice as much memory. We only store Rank for roots and Parent for non-roots, and this would have us store both for both.
We could store a union, though...


https://reviews.llvm.org/D40427