[PATCH] D25506: [LCG] Add utilities to compute parent and ascestor relationships between SCCs.

[Chandler Carruth via llvm-commits]

chandlerc added inline comments.


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Comment at: lib/Analysis/LazyCallGraph.cpp:212
+  SmallPtrSet<Node *, 16> Visited(Nodes.begin(), Nodes.end());
+  SmallVector<Node *, 16> Worklist(Nodes.begin(), Nodes.end());
+
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sanjoy wrote:
> Why not walk over `SCC` instances directly?  The way you've written these, I think you'll spend time "re-discovering" the SCC structures (that is walking intra-SCC call edges) when that is avoidable.
Good idea. I was thinking that it wouldn't be any better to do this because we have to walk the nodes anyways, but you're totally right this is much more efficient if it collapses immediately to SCCs. Please have a look and make sure this matches what you expected.


https://reviews.llvm.org/D25506