[llvm] [LTO] Introduce a helper function summarizeImports (NFC) (PR #106179)

[Teresa Johnson via llvm-commits]

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@@ -1082,21 +1082,29 @@ numGlobalVarSummaries(const ModuleSummaryIndex &Index,
   return NumGVS;
 }
 
-// Given ImportMap, return the number of global variable summaries and record
-// the number of defined function summaries as output parameter.
-static unsigned
-numGlobalVarSummaries(const ModuleSummaryIndex &Index,
-                      const FunctionImporter::FunctionsToImportTy &ImportMap,
-                      unsigned &DefinedFS) {
+struct ImportSummary {
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teresajohnson wrote:

Agree, the word summary ends up being overloaded - I like "Statistics" (here and in the uses where the stats get dumped later on) better.

https://github.com/llvm/llvm-project/pull/106179