/**
* Perform cross-module importing for the module identified by ModuleIdentifier.
*/
void ThinLTOCodeGenerator::crossModuleImport(Module &TheModule,
ModuleSummaryIndex &Index) {
auto ModuleMap = generateModuleMap(Modules);
auto ModuleCount = Index.modulePaths().size();
// Collect for each module the list of function it defines (GUID -> Summary).
StringMap<GVSummaryMapTy> ModuleToDefinedGVSummaries(ModuleCount);
Index.collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
// Generate import/export list
StringMap<FunctionImporter::ImportMapTy> ImportLists(ModuleCount);
StringMap<FunctionImporter::ExportSetTy> ExportLists(ModuleCount);
ComputeCrossModuleImport(Index, ModuleToDefinedGVSummaries, ImportLists,
ExportLists);
auto &ImportList = ImportLists[TheModule.getModuleIdentifier()];
crossImportIntoModule(TheModule, Index, ModuleMap, ImportList);
}
/**
* Compute the list of summaries needed for importing into module.
*/
void ThinLTOCodeGenerator::gatherImportedSummariesForModule(
StringRef ModulePath, ModuleSummaryIndex &Index,
std::map<std::string, GVSummaryMapTy> &ModuleToSummariesForIndex) {
auto ModuleCount = Index.modulePaths().size();
// Collect for each module the list of function it defines (GUID -> Summary).
StringMap<GVSummaryMapTy> ModuleToDefinedGVSummaries(ModuleCount);
Index.collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
// Generate import/export list
StringMap<FunctionImporter::ImportMapTy> ImportLists(ModuleCount);
StringMap<FunctionImporter::ExportSetTy> ExportLists(ModuleCount);
ComputeCrossModuleImport(Index, ModuleToDefinedGVSummaries, ImportLists,
ExportLists);
llvm::gatherImportedSummariesForModule(ModulePath, ModuleToDefinedGVSummaries,
ImportLists[ModulePath],
ModuleToSummariesForIndex);
}
/**
* Emit the list of files needed for importing into module.
*/
void ThinLTOCodeGenerator::emitImports(StringRef ModulePath,
StringRef OutputName,
ModuleSummaryIndex &Index) {
auto ModuleCount = Index.modulePaths().size();
// Collect for each module the list of function it defines (GUID -> Summary).
StringMap<GVSummaryMapTy> ModuleToDefinedGVSummaries(ModuleCount);
Index.collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
// Generate import/export list
StringMap<FunctionImporter::ImportMapTy> ImportLists(ModuleCount);
StringMap<FunctionImporter::ExportSetTy> ExportLists(ModuleCount);
ComputeCrossModuleImport(Index, ModuleToDefinedGVSummaries, ImportLists,
ExportLists);
std::error_code EC;
if ((EC = EmitImportsFiles(ModulePath, OutputName, ImportLists[ModulePath])))
report_fatal_error(Twine("Failed to open ") + OutputName +
" to save imports lists\n");
}
/**
* Perform promotion and renaming of exported internal functions.
* Index is updated to reflect linkage changes from weak resolution.
*/
void ThinLTOCodeGenerator::promote(Module &TheModule,
ModuleSummaryIndex &Index) {
auto ModuleCount = Index.modulePaths().size();
auto ModuleIdentifier = TheModule.getModuleIdentifier();
// Collect for each module the list of function it defines (GUID -> Summary).
StringMap<GVSummaryMapTy> ModuleToDefinedGVSummaries;
Index.collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
// Generate import/export list
StringMap<FunctionImporter::ImportMapTy> ImportLists(ModuleCount);
StringMap<FunctionImporter::ExportSetTy> ExportLists(ModuleCount);
ComputeCrossModuleImport(Index, ModuleToDefinedGVSummaries, ImportLists,
ExportLists);
// Resolve LinkOnce/Weak symbols.
StringMap<std::map<GlobalValue::GUID, GlobalValue::LinkageTypes>> ResolvedODR;
resolveWeakForLinkerInIndex(Index, ResolvedODR);
thinLTOResolveWeakForLinkerModule(
TheModule, ModuleToDefinedGVSummaries[ModuleIdentifier]);
// Convert the preserved symbols set from string to GUID
auto GUIDPreservedSymbols = computeGUIDPreservedSymbols(
PreservedSymbols, Triple(TheModule.getTargetTriple()));
// Promote the exported values in the index, so that they are promoted
// in the module.
auto isExported = [&](StringRef ModuleIdentifier, GlobalValue::GUID GUID) {
const auto &ExportList = ExportLists.find(ModuleIdentifier);
return (ExportList != ExportLists.end() &&
ExportList->second.count(GUID)) ||
GUIDPreservedSymbols.count(GUID);
};
thinLTOInternalizeAndPromoteInIndex(Index, isExported);
promoteModule(TheModule, Index);
}
/**
* Perform internalization. Index is updated to reflect linkage changes.
*/
void ThinLTOCodeGenerator::internalize(Module &TheModule,
ModuleSummaryIndex &Index) {
initTMBuilder(TMBuilder, Triple(TheModule.getTargetTriple()));
auto ModuleCount = Index.modulePaths().size();
auto ModuleIdentifier = TheModule.getModuleIdentifier();
// Convert the preserved symbols set from string to GUID
auto GUIDPreservedSymbols =
computeGUIDPreservedSymbols(PreservedSymbols, TMBuilder.TheTriple);
// Collect for each module the list of function it defines (GUID -> Summary).
StringMap<GVSummaryMapTy> ModuleToDefinedGVSummaries(ModuleCount);
Index.collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
// Generate import/export list
StringMap<FunctionImporter::ImportMapTy> ImportLists(ModuleCount);
StringMap<FunctionImporter::ExportSetTy> ExportLists(ModuleCount);
ComputeCrossModuleImport(Index, ModuleToDefinedGVSummaries, ImportLists,
ExportLists);
auto &ExportList = ExportLists[ModuleIdentifier];
// Be friendly and don't nuke totally the module when the client didn't
// supply anything to preserve.
if (ExportList.empty() && GUIDPreservedSymbols.empty())
return;
// Internalization
auto isExported = [&](StringRef ModuleIdentifier, GlobalValue::GUID GUID) {
const auto &ExportList = ExportLists.find(ModuleIdentifier);
return (ExportList != ExportLists.end() &&
ExportList->second.count(GUID)) ||
GUIDPreservedSymbols.count(GUID);
};
thinLTOInternalizeAndPromoteInIndex(Index, isExported);
thinLTOInternalizeModule(TheModule,
ModuleToDefinedGVSummaries[ModuleIdentifier]);
}
