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

[Jan Voung via llvm-commits]

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@@ -1108,19 +1118,19 @@ void llvm::ComputeCrossModuleImport(
           for (const auto &VI : GVS->refs()) {
             // Try to emplace the declaration entry. If a definition entry
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jvoung wrote:

nit: can remove the comment "// Try to emplace the declaration entry ..."?

Same below at lines 1128 and 1133

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