[llvm] [ThinLTO][BitcodeWriter] Write import type in per-module combined summary (PR #87600)

[Jan Voung via llvm-commits]

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@@ -1272,6 +1272,12 @@ using ModulePathStringTableTy = StringMap<ModuleHash>;
 /// a particular module, and provide efficient access to their summary.
 using GVSummaryMapTy = DenseMap<GlobalValue::GUID, GlobalValueSummary *>;
 
+/// A set of global value summary pointers.
+using GVSummaryPtrSet = SmallPtrSet<GlobalValueSummary *, 4>;
+
+/// The key is module path, and value is a set of global value summary pointers.
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jvoung wrote:

Not a big issue, but was wondering if the module path is needed or if a set instead of map would work? It seemed like each GlobalValueSummary* would only be imported from one module for declaration. Or is it possible that for a particular GVS_i ?

mod_A -> GVS_i
mod_B -> GVS_i

Otherwise, the map does match the gatherImportedSummariesForModule more closely.


https://github.com/llvm/llvm-project/pull/87600