/// Compute all the imports for the given module in the Index.
void llvm::ComputeCrossModuleImportForModule(
StringRef ModulePath, const ModuleSummaryIndex &Index,
FunctionImporter::ImportMapTy &ImportList) {
// Collect the list of functions this module defines.
// GUID -> Summary
GVSummaryMapTy FunctionSummaryMap;
Index.collectDefinedFunctionsForModule(ModulePath, FunctionSummaryMap);
// Compute the import list for this module.
DEBUG(dbgs() << "Computing import for Module '" << ModulePath << "'\n");
ComputeImportForModule(FunctionSummaryMap, Index, ImportList);
#ifndef NDEBUG
DEBUG(dbgs() << "* Module " << ModulePath << " imports from "
<< ImportList.size() << " modules.\n");
for (auto &Src : ImportList) {
auto SrcModName = Src.first();
DEBUG(dbgs() << " - " << Src.second.size() << " functions imported from "
<< SrcModName << "\n");
}
#endif
}
// Automatically import functions in Module \p DestModule based on the summaries
// index.
//
Expected<bool> FunctionImporter::importFunctions(
Module &DestModule, const FunctionImporter::ImportMapTy &ImportList,
bool ForceImportReferencedDiscardableSymbols) {
DEBUG(dbgs() << "Starting import for Module "
<< DestModule.getModuleIdentifier() << "\n");
unsigned ImportedCount = 0;
// Linker that will be used for importing function
Linker TheLinker(DestModule);
// Do the actual import of functions now, one Module at a time
std::set<StringRef> ModuleNameOrderedList;
for (auto &FunctionsToImportPerModule : ImportList) {
ModuleNameOrderedList.insert(FunctionsToImportPerModule.first());
}
for (auto &Name : ModuleNameOrderedList) {
// Get the module for the import
const auto &FunctionsToImportPerModule = ImportList.find(Name);
assert(FunctionsToImportPerModule != ImportList.end());
Expected<std::unique_ptr<Module>> SrcModuleOrErr = ModuleLoader(Name);
if (!SrcModuleOrErr)
return SrcModuleOrErr.takeError();
std::unique_ptr<Module> SrcModule = std::move(*SrcModuleOrErr);
assert(&DestModule.getContext() == &SrcModule->getContext() &&
"Context mismatch");
// If modules were created with lazy metadata loading, materialize it
// now, before linking it (otherwise this will be a noop).
if (Error Err = SrcModule->materializeMetadata())
return std::move(Err);
UpgradeDebugInfo(*SrcModule);
auto &ImportGUIDs = FunctionsToImportPerModule->second;
// Find the globals to import
DenseSet<const GlobalValue *> GlobalsToImport;
for (Function &F : *SrcModule) {
if (!F.hasName())
continue;
auto GUID = F.getGUID();
auto Import = ImportGUIDs.count(GUID);
DEBUG(dbgs() << (Import ? "Is" : "Not") << " importing function " << GUID
<< " " << F.getName() << " from "
<< SrcModule->getSourceFileName() << "\n");
if (Import) {
if (Error Err = F.materialize())
return std::move(Err);
if (EnableImportMetadata) {
// Add 'thinlto_src_module' metadata for statistics and debugging.
F.setMetadata(
"thinlto_src_module",
llvm::MDNode::get(
DestModule.getContext(),
{llvm::MDString::get(DestModule.getContext(),
SrcModule->getSourceFileName())}));
}
GlobalsToImport.insert(&F);
}
}
for (GlobalVariable &GV : SrcModule->globals()) {
if (!GV.hasName())
continue;
auto GUID = GV.getGUID();
auto Import = ImportGUIDs.count(GUID);
DEBUG(dbgs() << (Import ? "Is" : "Not") << " importing global " << GUID
<< " " << GV.getName() << " from "
<< SrcModule->getSourceFileName() << "\n");
if (Import) {
if (Error Err = GV.materialize())
return std::move(Err);
GlobalsToImport.insert(&GV);
}
}
for (GlobalAlias &GA : SrcModule->aliases()) {
if (!GA.hasName())
continue;
auto GUID = GA.getGUID();
auto Import = ImportGUIDs.count(GUID);
DEBUG(dbgs() << (Import ? "Is" : "Not") << " importing alias " << GUID
<< " " << GA.getName() << " from "
<< SrcModule->getSourceFileName() << "\n");
if (Import) {
// Alias can't point to "available_externally". However when we import
// linkOnceODR the linkage does not change. So we import the alias
// and aliasee only in this case. This has been handled by
// computeImportForFunction()
GlobalObject *GO = GA.getBaseObject();
assert(GO->hasLinkOnceODRLinkage() &&
"Unexpected alias to a non-linkonceODR in import list");
#ifndef NDEBUG
if (!GlobalsToImport.count(GO))
DEBUG(dbgs() << " alias triggers importing aliasee " << GO->getGUID()
<< " " << GO->getName() << " from "
<< SrcModule->getSourceFileName() << "\n");
#endif
if (Error Err = GO->materialize())
return std::move(Err);
GlobalsToImport.insert(GO);
if (Error Err = GA.materialize())
return std::move(Err);
GlobalsToImport.insert(&GA);
}
}
// Link in the specified functions.
if (renameModuleForThinLTO(*SrcModule, Index, &GlobalsToImport))
return true;
if (PrintImports) {
for (const auto *GV : GlobalsToImport)
dbgs() << DestModule.getSourceFileName() << ": Import " << GV->getName()
<< " from " << SrcModule->getSourceFileName() << "\n";
}
// Instruct the linker that the client will take care of linkonce resolution
unsigned Flags = Linker::Flags::None;
if (!ForceImportReferencedDiscardableSymbols)
Flags |= Linker::Flags::DontForceLinkLinkonceODR;
if (TheLinker.linkInModule(std::move(SrcModule), Flags, &GlobalsToImport))
report_fatal_error("Function Import: link error");
ImportedCount += GlobalsToImport.size();
}
NumImported += ImportedCount;
DEBUG(dbgs() << "Imported " << ImportedCount << " functions for Module "
<< DestModule.getModuleIdentifier() << "\n");
return ImportedCount;
}
// Automatically import functions in Module \p DestModule based on the summaries
// index.
//
bool FunctionImporter::importFunctions(
Module &DestModule, const FunctionImporter::ImportMapTy &ImportList) {
DEBUG(dbgs() << "Starting import for Module "
<< DestModule.getModuleIdentifier() << "\n");
unsigned ImportedCount = 0;
// Linker that will be used for importing function
Linker TheLinker(DestModule);
// Do the actual import of functions now, one Module at a time
std::set<StringRef> ModuleNameOrderedList;
for (auto &FunctionsToImportPerModule : ImportList) {
ModuleNameOrderedList.insert(FunctionsToImportPerModule.first());
}
for (auto &Name : ModuleNameOrderedList) {
// Get the module for the import
const auto &FunctionsToImportPerModule = ImportList.find(Name);
assert(FunctionsToImportPerModule != ImportList.end());
std::unique_ptr<Module> SrcModule = ModuleLoader(Name);
assert(&DestModule.getContext() == &SrcModule->getContext() &&
"Context mismatch");
// If modules were created with lazy metadata loading, materialize it
// now, before linking it (otherwise this will be a noop).
SrcModule->materializeMetadata();
UpgradeDebugInfo(*SrcModule);
auto &ImportGUIDs = FunctionsToImportPerModule->second;
// Find the globals to import
DenseSet<const GlobalValue *> GlobalsToImport;
for (auto &GV : *SrcModule) {
if (!GV.hasName())
continue;
auto GUID = GV.getGUID();
auto Import = ImportGUIDs.count(GUID);
DEBUG(dbgs() << (Import ? "Is" : "Not") << " importing " << GUID << " "
<< GV.getName() << " from " << SrcModule->getSourceFileName()
<< "\n");
if (Import) {
GV.materialize();
GlobalsToImport.insert(&GV);
}
}
for (auto &GV : SrcModule->globals()) {
if (!GV.hasName())
continue;
auto GUID = GV.getGUID();
auto Import = ImportGUIDs.count(GUID);
DEBUG(dbgs() << (Import ? "Is" : "Not") << " importing " << GUID << " "
<< GV.getName() << " from " << SrcModule->getSourceFileName()
<< "\n");
if (Import) {
GV.materialize();
GlobalsToImport.insert(&GV);
}
}
for (auto &GV : SrcModule->aliases()) {
if (!GV.hasName())
continue;
auto GUID = GV.getGUID();
auto Import = ImportGUIDs.count(GUID);
DEBUG(dbgs() << (Import ? "Is" : "Not") << " importing " << GUID << " "
<< GV.getName() << " from " << SrcModule->getSourceFileName()
<< "\n");
if (Import) {
// Alias can't point to "available_externally". However when we import
// linkOnceODR the linkage does not change. So we import the alias
// and aliasee only in this case.
GlobalObject *GO = GV.getBaseObject();
if (!GO->hasLinkOnceODRLinkage())
continue;
#ifndef NDEBUG
if (!GlobalsToImport.count(GO))
DEBUG(dbgs() << " alias triggers importing aliasee " << GO->getGUID()
<< " " << GO->getName() << " from "
<< SrcModule->getSourceFileName() << "\n");
#endif
GO->materialize();
GlobalsToImport.insert(GO);
GV.materialize();
GlobalsToImport.insert(&GV);
}
}
// Link in the specified functions.
if (renameModuleForThinLTO(*SrcModule, Index, &GlobalsToImport))
return true;
if (PrintImports) {
for (const auto *GV : GlobalsToImport)
dbgs() << DestModule.getSourceFileName() << ": Import " << GV->getName()
<< " from " << SrcModule->getSourceFileName() << "\n";
}
if (TheLinker.linkInModule(std::move(SrcModule), Linker::Flags::None,
&GlobalsToImport))
report_fatal_error("Function Import: link error");
ImportedCount += GlobalsToImport.size();
}
NumImported += ImportedCount;
DEBUG(dbgs() << "Imported " << ImportedCount << " functions for Module "
<< DestModule.getModuleIdentifier() << "\n");
return ImportedCount;
}