[llvm] [MemProf] Reduce cloning overhead by sharing nodes when possible (PR #99832)

[Teresa Johnson via llvm-commits]

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@@ -1757,6 +1815,7 @@ IndexCallsiteContextGraph::IndexCallsiteContextGraph(
           if (AN.MIBs.empty())
             continue;
           CallsWithMetadata.push_back({&AN});
+          CallToFunc[{&AN}] = FS;
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teresajohnson wrote:

The other places like this were on the adjacent lines, so I went ahead and did a bit of refactoring to clean them all up.

https://github.com/llvm/llvm-project/pull/99832