1 //===-LTOBackend.cpp - LLVM Link Time Optimizer Backend -------------------===//
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
14 //===----------------------------------------------------------------------===//
53 #define DEBUG_TYPE "lto-backend"
62     "lto-embed-bitcode", cl::init(LTOBitcodeEmbedding::DoNotEmbed),
68                           "post-merge-pre-opt",
73     "thinlto-assume-merged", cl::init(false),
75              "importing and the other pre-optimization pipeline changes."));
115       if (M.getModuleIdentifier() == "ld-temp.o" || !UseInputModulePath) {  in addSaveTemps()
117         if (Task != (unsigned)-1)  in addSaveTemps()
124       // Because -save-temps is a debugging feature, we report the error  in addSaveTemps()
139         // Because -save-temps is a debugging feature, we report the error  in addSaveTemps()
196     PassPlugin->registerPassBuilderCallbacks(PB);  in RegisterPassPlugins()
221   std::unique_ptr<TargetMachine> TM(TheTarget->createTargetMachine(  in createTargetMachine()
228     TM->setLargeDataThreshold(*LargeDataThreshold);  in createTargetMachine()
260   TM->setPGOOption(PGOOpt);  in runNewPMPasses()
276       new TargetLibraryInfoImpl(Triple(TM->getTargetTriple())));  in runNewPMPasses()
278     TLII->disableAllFunctions();  in runNewPMPasses()
281   // Parse a custom AA pipeline if asked to.  in runNewPMPasses()
323   // Parse a custom pipeline if asked to.  in runNewPMPasses()
346     // FIXME: the motivation for capturing post-merge bitcode and command line  in opt()
349     // assumes a clang - based invocation, case in which we have the command  in opt()
352     // linker-based case, so we currently don't plumb the command line args in  in opt()
356           dbgs() << "Post-(Thin)LTO merge bitcode embedding was requested, but "  in opt()
390     TM->Options.MCOptions.SplitDwarfFile = std::string(DwoFile);  in codegen()
392     TM->Options.MCOptions.SplitDwarfFile = Conf.SplitDwarfFile;  in codegen()
407   TM->Options.ObjectFilenameForDebug = Stream->ObjectPathName;  in codegen()
416   if (TM->addPassesToEmitFile(CodeGenPasses, *Stream->OS,  in codegen()
417                               DwoOut ? &DwoOut->os() : nullptr,  in codegen()
423     DwoOut->keep();  in codegen()
433   const Target *T = &TM->getTarget();  in splitCodeGen()
437         // We want to clone the module in a new context to multi-thread the  in splitCodeGen()
452                   parseBitcodeFile(MemoryBufferRef(BC.str(), "ld-temp.o"), Ctx);  in splitCodeGen()
468   // Try target-specific module splitting first, then fallback to the default.  in splitCodeGen()
469   if (!TM->splitModule(Mod, ParallelCodeGenParallelismLevel,  in splitCodeGen()
501   DiagOutputFile->keep();  in finalizeOptimizationRemarks()
502   DiagOutputFile->os().flush();  in finalizeOptimizationRemarks()
545     GV->removeDeadConstantUsers();  in dropDeadSymbols()
547     // non-prevailing IR def, but we need to keep the declaration).  in dropDeadSymbols()
548     if (GV->use_empty())  in dropDeadSymbols()
549       GV->eraseFromParent();  in dropDeadSymbols()
603   // conservatively do this for -fpic.  in thinBackend()
605       TM->getTargetTriple().isOSBinFormatELF() &&  in thinBackend()
606       TM->getRelocationModel() != Reloc::Static &&  in thinBackend()
628       auto I = ModuleMap->find(Identifier);  in thinBackend()
629       assert(I != ModuleMap->end());  in thinBackend()
630       return I->second.getLazyModule(Mod.getContext(),  in thinBackend()
650         BMOrErr->getLazyModule(Mod.getContext(),  in thinBackend()
654       (*MOrErr)->setOwnedMemoryBuffer(std::move(*MBOrErr));  in thinBackend()
679     if (LTOInfo && LTOInfo->IsThinLTO)  in findThinLTOModule()
716       if (Summary->modulePath() == M.getModuleIdentifier())  in initImportList()
720       // exists, set the value to 'std::min(existing-value, new-value)' to make  in initImportList()
722       auto [Iter, Inserted] = ImportList[Summary->modulePath()].try_emplace(  in initImportList()
723           GUID, Summary->importType());  in initImportList()
726         Iter->second = std::min(Iter->second, Summary->importType());  in initImportList()