[llvm] [ThinLTO] Use a set rather than a map to track exported ValueInfos. (PR #97360)

[Teresa Johnson via llvm-commits]

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@@ -995,26 +995,19 @@ static bool isGlobalVarSummary(const ModuleSummaryIndex &Index,
   return false;
 }
 
-// Return the number of global summaries and record the number of function
-// summaries as output parameter.
-static unsigned numGlobalVarSummaries(const ModuleSummaryIndex &Index,
-                                      FunctionImporter::ExportSetTy &ExportSet,
-                                      unsigned &DefinedFS) {
+// Return the number of global summaries in ExportSet.
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teresajohnson wrote:

"global variable summaries" (to distinguish from global value summaries).

https://github.com/llvm/llvm-project/pull/97360