1 //===-LTOBackend.cpp - LLVM Link Time Optimizer Backend -------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file implements the "backend" phase of LTO, i.e. it performs 10 // optimization and code generation on a loaded module. It is generally used 11 // internally by the LTO class but can also be used independently, for example 12 // to implement a standalone ThinLTO backend. 13 // 14 //===----------------------------------------------------------------------===// 15 16 #include "llvm/LTO/LTOBackend.h" 17 #include "llvm/Analysis/AliasAnalysis.h" 18 #include "llvm/Analysis/CGSCCPassManager.h" 19 #include "llvm/Analysis/TargetLibraryInfo.h" 20 #include "llvm/Analysis/TargetTransformInfo.h" 21 #include "llvm/Bitcode/BitcodeReader.h" 22 #include "llvm/Bitcode/BitcodeWriter.h" 23 #include "llvm/IR/LegacyPassManager.h" 24 #include "llvm/IR/PassManager.h" 25 #include "llvm/IR/RemarkStreamer.h" 26 #include "llvm/IR/Verifier.h" 27 #include "llvm/LTO/LTO.h" 28 #include "llvm/MC/SubtargetFeature.h" 29 #include "llvm/Object/ModuleSymbolTable.h" 30 #include "llvm/Passes/PassBuilder.h" 31 #include "llvm/Support/Error.h" 32 #include "llvm/Support/FileSystem.h" 33 #include "llvm/Support/MemoryBuffer.h" 34 #include "llvm/Support/Path.h" 35 #include "llvm/Support/Program.h" 36 #include "llvm/Support/TargetRegistry.h" 37 #include "llvm/Support/ThreadPool.h" 38 #include "llvm/Support/raw_ostream.h" 39 #include "llvm/Target/TargetMachine.h" 40 #include "llvm/Transforms/IPO.h" 41 #include "llvm/Transforms/IPO/PassManagerBuilder.h" 42 #include "llvm/Transforms/Scalar/LoopPassManager.h" 43 #include "llvm/Transforms/Utils/FunctionImportUtils.h" 44 #include "llvm/Transforms/Utils/SplitModule.h" 45 46 using namespace llvm; 47 using namespace lto; 48 49 LLVM_ATTRIBUTE_NORETURN static void reportOpenError(StringRef Path, Twine Msg) { 50 errs() << "failed to open " << Path << ": " << Msg << '\n'; 51 errs().flush(); 52 exit(1); 53 } 54 55 Error Config::addSaveTemps(std::string OutputFileName, 56 bool UseInputModulePath) { 57 ShouldDiscardValueNames = false; 58 59 std::error_code EC; 60 ResolutionFile = llvm::make_unique<raw_fd_ostream>( 61 OutputFileName + "resolution.txt", EC, sys::fs::OpenFlags::F_Text); 62 if (EC) 63 return errorCodeToError(EC); 64 65 auto setHook = [&](std::string PathSuffix, ModuleHookFn &Hook) { 66 // Keep track of the hook provided by the linker, which also needs to run. 67 ModuleHookFn LinkerHook = Hook; 68 Hook = [=](unsigned Task, const Module &M) { 69 // If the linker's hook returned false, we need to pass that result 70 // through. 71 if (LinkerHook && !LinkerHook(Task, M)) 72 return false; 73 74 std::string PathPrefix; 75 // If this is the combined module (not a ThinLTO backend compile) or the 76 // user hasn't requested using the input module's path, emit to a file 77 // named from the provided OutputFileName with the Task ID appended. 78 if (M.getModuleIdentifier() == "ld-temp.o" || !UseInputModulePath) { 79 PathPrefix = OutputFileName; 80 if (Task != (unsigned)-1) 81 PathPrefix += utostr(Task) + "."; 82 } else 83 PathPrefix = M.getModuleIdentifier() + "."; 84 std::string Path = PathPrefix + PathSuffix + ".bc"; 85 std::error_code EC; 86 raw_fd_ostream OS(Path, EC, sys::fs::OpenFlags::F_None); 87 // Because -save-temps is a debugging feature, we report the error 88 // directly and exit. 89 if (EC) 90 reportOpenError(Path, EC.message()); 91 WriteBitcodeToFile(M, OS, /*ShouldPreserveUseListOrder=*/false); 92 return true; 93 }; 94 }; 95 96 setHook("0.preopt", PreOptModuleHook); 97 setHook("1.promote", PostPromoteModuleHook); 98 setHook("2.internalize", PostInternalizeModuleHook); 99 setHook("3.import", PostImportModuleHook); 100 setHook("4.opt", PostOptModuleHook); 101 setHook("5.precodegen", PreCodeGenModuleHook); 102 103 CombinedIndexHook = [=](const ModuleSummaryIndex &Index) { 104 std::string Path = OutputFileName + "index.bc"; 105 std::error_code EC; 106 raw_fd_ostream OS(Path, EC, sys::fs::OpenFlags::F_None); 107 // Because -save-temps is a debugging feature, we report the error 108 // directly and exit. 109 if (EC) 110 reportOpenError(Path, EC.message()); 111 WriteIndexToFile(Index, OS); 112 113 Path = OutputFileName + "index.dot"; 114 raw_fd_ostream OSDot(Path, EC, sys::fs::OpenFlags::F_None); 115 if (EC) 116 reportOpenError(Path, EC.message()); 117 Index.exportToDot(OSDot); 118 return true; 119 }; 120 121 return Error::success(); 122 } 123 124 namespace { 125 126 std::unique_ptr<TargetMachine> 127 createTargetMachine(Config &Conf, const Target *TheTarget, Module &M) { 128 StringRef TheTriple = M.getTargetTriple(); 129 SubtargetFeatures Features; 130 Features.getDefaultSubtargetFeatures(Triple(TheTriple)); 131 for (const std::string &A : Conf.MAttrs) 132 Features.AddFeature(A); 133 134 Reloc::Model RelocModel; 135 if (Conf.RelocModel) 136 RelocModel = *Conf.RelocModel; 137 else 138 RelocModel = 139 M.getPICLevel() == PICLevel::NotPIC ? Reloc::Static : Reloc::PIC_; 140 141 Optional<CodeModel::Model> CodeModel; 142 if (Conf.CodeModel) 143 CodeModel = *Conf.CodeModel; 144 else 145 CodeModel = M.getCodeModel(); 146 147 return std::unique_ptr<TargetMachine>(TheTarget->createTargetMachine( 148 TheTriple, Conf.CPU, Features.getString(), Conf.Options, RelocModel, 149 CodeModel, Conf.CGOptLevel)); 150 } 151 152 static void runNewPMPasses(Config &Conf, Module &Mod, TargetMachine *TM, 153 unsigned OptLevel, bool IsThinLTO, 154 ModuleSummaryIndex *ExportSummary, 155 const ModuleSummaryIndex *ImportSummary) { 156 Optional<PGOOptions> PGOOpt; 157 if (!Conf.SampleProfile.empty()) 158 PGOOpt = PGOOptions(Conf.SampleProfile, "", Conf.ProfileRemapping, 159 PGOOptions::SampleUse, PGOOptions::NoCSAction, true); 160 else if (Conf.RunCSIRInstr) { 161 PGOOpt = PGOOptions("", Conf.CSIRProfile, Conf.ProfileRemapping, 162 PGOOptions::IRUse, PGOOptions::CSIRInstr); 163 } else if (!Conf.CSIRProfile.empty()) { 164 PGOOpt = PGOOptions(Conf.CSIRProfile, "", Conf.ProfileRemapping, 165 PGOOptions::IRUse, PGOOptions::CSIRUse); 166 } 167 168 PassBuilder PB(TM, PipelineTuningOptions(), PGOOpt); 169 AAManager AA; 170 171 // Parse a custom AA pipeline if asked to. 172 if (auto Err = PB.parseAAPipeline(AA, "default")) 173 report_fatal_error("Error parsing default AA pipeline"); 174 175 LoopAnalysisManager LAM(Conf.DebugPassManager); 176 FunctionAnalysisManager FAM(Conf.DebugPassManager); 177 CGSCCAnalysisManager CGAM(Conf.DebugPassManager); 178 ModuleAnalysisManager MAM(Conf.DebugPassManager); 179 180 // Register the AA manager first so that our version is the one used. 181 FAM.registerPass([&] { return std::move(AA); }); 182 183 // Register all the basic analyses with the managers. 184 PB.registerModuleAnalyses(MAM); 185 PB.registerCGSCCAnalyses(CGAM); 186 PB.registerFunctionAnalyses(FAM); 187 PB.registerLoopAnalyses(LAM); 188 PB.crossRegisterProxies(LAM, FAM, CGAM, MAM); 189 190 ModulePassManager MPM(Conf.DebugPassManager); 191 // FIXME (davide): verify the input. 192 193 PassBuilder::OptimizationLevel OL; 194 195 switch (OptLevel) { 196 default: 197 llvm_unreachable("Invalid optimization level"); 198 case 0: 199 OL = PassBuilder::O0; 200 break; 201 case 1: 202 OL = PassBuilder::O1; 203 break; 204 case 2: 205 OL = PassBuilder::O2; 206 break; 207 case 3: 208 OL = PassBuilder::O3; 209 break; 210 } 211 212 if (IsThinLTO) 213 MPM = PB.buildThinLTODefaultPipeline(OL, Conf.DebugPassManager, 214 ImportSummary); 215 else 216 MPM = PB.buildLTODefaultPipeline(OL, Conf.DebugPassManager, ExportSummary); 217 MPM.run(Mod, MAM); 218 219 // FIXME (davide): verify the output. 220 } 221 222 static void runNewPMCustomPasses(Module &Mod, TargetMachine *TM, 223 std::string PipelineDesc, 224 std::string AAPipelineDesc, 225 bool DisableVerify) { 226 PassBuilder PB(TM); 227 AAManager AA; 228 229 // Parse a custom AA pipeline if asked to. 230 if (!AAPipelineDesc.empty()) 231 if (auto Err = PB.parseAAPipeline(AA, AAPipelineDesc)) 232 report_fatal_error("unable to parse AA pipeline description '" + 233 AAPipelineDesc + "': " + toString(std::move(Err))); 234 235 LoopAnalysisManager LAM; 236 FunctionAnalysisManager FAM; 237 CGSCCAnalysisManager CGAM; 238 ModuleAnalysisManager MAM; 239 240 // Register the AA manager first so that our version is the one used. 241 FAM.registerPass([&] { return std::move(AA); }); 242 243 // Register all the basic analyses with the managers. 244 PB.registerModuleAnalyses(MAM); 245 PB.registerCGSCCAnalyses(CGAM); 246 PB.registerFunctionAnalyses(FAM); 247 PB.registerLoopAnalyses(LAM); 248 PB.crossRegisterProxies(LAM, FAM, CGAM, MAM); 249 250 ModulePassManager MPM; 251 252 // Always verify the input. 253 MPM.addPass(VerifierPass()); 254 255 // Now, add all the passes we've been requested to. 256 if (auto Err = PB.parsePassPipeline(MPM, PipelineDesc)) 257 report_fatal_error("unable to parse pass pipeline description '" + 258 PipelineDesc + "': " + toString(std::move(Err))); 259 260 if (!DisableVerify) 261 MPM.addPass(VerifierPass()); 262 MPM.run(Mod, MAM); 263 } 264 265 static void runOldPMPasses(Config &Conf, Module &Mod, TargetMachine *TM, 266 bool IsThinLTO, ModuleSummaryIndex *ExportSummary, 267 const ModuleSummaryIndex *ImportSummary) { 268 legacy::PassManager passes; 269 passes.add(createTargetTransformInfoWrapperPass(TM->getTargetIRAnalysis())); 270 271 PassManagerBuilder PMB; 272 PMB.LibraryInfo = new TargetLibraryInfoImpl(Triple(TM->getTargetTriple())); 273 PMB.Inliner = createFunctionInliningPass(); 274 PMB.ExportSummary = ExportSummary; 275 PMB.ImportSummary = ImportSummary; 276 // Unconditionally verify input since it is not verified before this 277 // point and has unknown origin. 278 PMB.VerifyInput = true; 279 PMB.VerifyOutput = !Conf.DisableVerify; 280 PMB.LoopVectorize = true; 281 PMB.SLPVectorize = true; 282 PMB.OptLevel = Conf.OptLevel; 283 PMB.PGOSampleUse = Conf.SampleProfile; 284 PMB.EnablePGOCSInstrGen = Conf.RunCSIRInstr; 285 if (!Conf.RunCSIRInstr && !Conf.CSIRProfile.empty()) { 286 PMB.EnablePGOCSInstrUse = true; 287 PMB.PGOInstrUse = Conf.CSIRProfile; 288 } 289 if (IsThinLTO) 290 PMB.populateThinLTOPassManager(passes); 291 else 292 PMB.populateLTOPassManager(passes); 293 passes.run(Mod); 294 } 295 296 bool opt(Config &Conf, TargetMachine *TM, unsigned Task, Module &Mod, 297 bool IsThinLTO, ModuleSummaryIndex *ExportSummary, 298 const ModuleSummaryIndex *ImportSummary) { 299 // FIXME: Plumb the combined index into the new pass manager. 300 if (!Conf.OptPipeline.empty()) 301 runNewPMCustomPasses(Mod, TM, Conf.OptPipeline, Conf.AAPipeline, 302 Conf.DisableVerify); 303 else if (Conf.UseNewPM) 304 runNewPMPasses(Conf, Mod, TM, Conf.OptLevel, IsThinLTO, ExportSummary, 305 ImportSummary); 306 else 307 runOldPMPasses(Conf, Mod, TM, IsThinLTO, ExportSummary, ImportSummary); 308 return !Conf.PostOptModuleHook || Conf.PostOptModuleHook(Task, Mod); 309 } 310 311 void codegen(Config &Conf, TargetMachine *TM, AddStreamFn AddStream, 312 unsigned Task, Module &Mod) { 313 if (Conf.PreCodeGenModuleHook && !Conf.PreCodeGenModuleHook(Task, Mod)) 314 return; 315 316 std::unique_ptr<ToolOutputFile> DwoOut; 317 SmallString<1024> DwoFile(Conf.SplitDwarfOutput); 318 if (!Conf.DwoDir.empty()) { 319 std::error_code EC; 320 if (auto EC = llvm::sys::fs::create_directories(Conf.DwoDir)) 321 report_fatal_error("Failed to create directory " + Conf.DwoDir + ": " + 322 EC.message()); 323 324 DwoFile = Conf.DwoDir; 325 sys::path::append(DwoFile, std::to_string(Task) + ".dwo"); 326 TM->Options.MCOptions.SplitDwarfFile = DwoFile.str().str(); 327 } else 328 TM->Options.MCOptions.SplitDwarfFile = Conf.SplitDwarfFile; 329 330 if (!DwoFile.empty()) { 331 std::error_code EC; 332 DwoOut = llvm::make_unique<ToolOutputFile>(DwoFile, EC, sys::fs::F_None); 333 if (EC) 334 report_fatal_error("Failed to open " + DwoFile + ": " + EC.message()); 335 } 336 337 auto Stream = AddStream(Task); 338 legacy::PassManager CodeGenPasses; 339 if (TM->addPassesToEmitFile(CodeGenPasses, *Stream->OS, 340 DwoOut ? &DwoOut->os() : nullptr, 341 Conf.CGFileType)) 342 report_fatal_error("Failed to setup codegen"); 343 CodeGenPasses.run(Mod); 344 345 if (DwoOut) 346 DwoOut->keep(); 347 } 348 349 void splitCodeGen(Config &C, TargetMachine *TM, AddStreamFn AddStream, 350 unsigned ParallelCodeGenParallelismLevel, 351 std::unique_ptr<Module> Mod) { 352 ThreadPool CodegenThreadPool(ParallelCodeGenParallelismLevel); 353 unsigned ThreadCount = 0; 354 const Target *T = &TM->getTarget(); 355 356 SplitModule( 357 std::move(Mod), ParallelCodeGenParallelismLevel, 358 [&](std::unique_ptr<Module> MPart) { 359 // We want to clone the module in a new context to multi-thread the 360 // codegen. We do it by serializing partition modules to bitcode 361 // (while still on the main thread, in order to avoid data races) and 362 // spinning up new threads which deserialize the partitions into 363 // separate contexts. 364 // FIXME: Provide a more direct way to do this in LLVM. 365 SmallString<0> BC; 366 raw_svector_ostream BCOS(BC); 367 WriteBitcodeToFile(*MPart, BCOS); 368 369 // Enqueue the task 370 CodegenThreadPool.async( 371 [&](const SmallString<0> &BC, unsigned ThreadId) { 372 LTOLLVMContext Ctx(C); 373 Expected<std::unique_ptr<Module>> MOrErr = parseBitcodeFile( 374 MemoryBufferRef(StringRef(BC.data(), BC.size()), "ld-temp.o"), 375 Ctx); 376 if (!MOrErr) 377 report_fatal_error("Failed to read bitcode"); 378 std::unique_ptr<Module> MPartInCtx = std::move(MOrErr.get()); 379 380 std::unique_ptr<TargetMachine> TM = 381 createTargetMachine(C, T, *MPartInCtx); 382 383 codegen(C, TM.get(), AddStream, ThreadId, *MPartInCtx); 384 }, 385 // Pass BC using std::move to ensure that it get moved rather than 386 // copied into the thread's context. 387 std::move(BC), ThreadCount++); 388 }, 389 false); 390 391 // Because the inner lambda (which runs in a worker thread) captures our local 392 // variables, we need to wait for the worker threads to terminate before we 393 // can leave the function scope. 394 CodegenThreadPool.wait(); 395 } 396 397 Expected<const Target *> initAndLookupTarget(Config &C, Module &Mod) { 398 if (!C.OverrideTriple.empty()) 399 Mod.setTargetTriple(C.OverrideTriple); 400 else if (Mod.getTargetTriple().empty()) 401 Mod.setTargetTriple(C.DefaultTriple); 402 403 std::string Msg; 404 const Target *T = TargetRegistry::lookupTarget(Mod.getTargetTriple(), Msg); 405 if (!T) 406 return make_error<StringError>(Msg, inconvertibleErrorCode()); 407 return T; 408 } 409 410 } 411 412 static Error 413 finalizeOptimizationRemarks(std::unique_ptr<ToolOutputFile> DiagOutputFile) { 414 // Make sure we flush the diagnostic remarks file in case the linker doesn't 415 // call the global destructors before exiting. 416 if (!DiagOutputFile) 417 return Error::success(); 418 DiagOutputFile->keep(); 419 DiagOutputFile->os().flush(); 420 return Error::success(); 421 } 422 423 Error lto::backend(Config &C, AddStreamFn AddStream, 424 unsigned ParallelCodeGenParallelismLevel, 425 std::unique_ptr<Module> Mod, 426 ModuleSummaryIndex &CombinedIndex) { 427 Expected<const Target *> TOrErr = initAndLookupTarget(C, *Mod); 428 if (!TOrErr) 429 return TOrErr.takeError(); 430 431 std::unique_ptr<TargetMachine> TM = createTargetMachine(C, *TOrErr, *Mod); 432 433 // Setup optimization remarks. 434 auto DiagFileOrErr = lto::setupOptimizationRemarks( 435 Mod->getContext(), C.RemarksFilename, C.RemarksPasses, C.RemarksFormat, 436 C.RemarksWithHotness); 437 if (!DiagFileOrErr) 438 return DiagFileOrErr.takeError(); 439 auto DiagnosticOutputFile = std::move(*DiagFileOrErr); 440 441 if (!C.CodeGenOnly) { 442 if (!opt(C, TM.get(), 0, *Mod, /*IsThinLTO=*/false, 443 /*ExportSummary=*/&CombinedIndex, /*ImportSummary=*/nullptr)) 444 return finalizeOptimizationRemarks(std::move(DiagnosticOutputFile)); 445 } 446 447 if (ParallelCodeGenParallelismLevel == 1) { 448 codegen(C, TM.get(), AddStream, 0, *Mod); 449 } else { 450 splitCodeGen(C, TM.get(), AddStream, ParallelCodeGenParallelismLevel, 451 std::move(Mod)); 452 } 453 return finalizeOptimizationRemarks(std::move(DiagnosticOutputFile)); 454 } 455 456 static void dropDeadSymbols(Module &Mod, const GVSummaryMapTy &DefinedGlobals, 457 const ModuleSummaryIndex &Index) { 458 std::vector<GlobalValue*> DeadGVs; 459 for (auto &GV : Mod.global_values()) 460 if (GlobalValueSummary *GVS = DefinedGlobals.lookup(GV.getGUID())) 461 if (!Index.isGlobalValueLive(GVS)) { 462 DeadGVs.push_back(&GV); 463 convertToDeclaration(GV); 464 } 465 466 // Now that all dead bodies have been dropped, delete the actual objects 467 // themselves when possible. 468 for (GlobalValue *GV : DeadGVs) { 469 GV->removeDeadConstantUsers(); 470 // Might reference something defined in native object (i.e. dropped a 471 // non-prevailing IR def, but we need to keep the declaration). 472 if (GV->use_empty()) 473 GV->eraseFromParent(); 474 } 475 } 476 477 Error lto::thinBackend(Config &Conf, unsigned Task, AddStreamFn AddStream, 478 Module &Mod, const ModuleSummaryIndex &CombinedIndex, 479 const FunctionImporter::ImportMapTy &ImportList, 480 const GVSummaryMapTy &DefinedGlobals, 481 MapVector<StringRef, BitcodeModule> &ModuleMap) { 482 Expected<const Target *> TOrErr = initAndLookupTarget(Conf, Mod); 483 if (!TOrErr) 484 return TOrErr.takeError(); 485 486 std::unique_ptr<TargetMachine> TM = createTargetMachine(Conf, *TOrErr, Mod); 487 488 // Setup optimization remarks. 489 auto DiagFileOrErr = lto::setupOptimizationRemarks( 490 Mod.getContext(), Conf.RemarksFilename, Conf.RemarksPasses, 491 Conf.RemarksFormat, Conf.RemarksWithHotness, Task); 492 if (!DiagFileOrErr) 493 return DiagFileOrErr.takeError(); 494 auto DiagnosticOutputFile = std::move(*DiagFileOrErr); 495 496 if (Conf.CodeGenOnly) { 497 codegen(Conf, TM.get(), AddStream, Task, Mod); 498 return finalizeOptimizationRemarks(std::move(DiagnosticOutputFile)); 499 } 500 501 if (Conf.PreOptModuleHook && !Conf.PreOptModuleHook(Task, Mod)) 502 return finalizeOptimizationRemarks(std::move(DiagnosticOutputFile)); 503 504 renameModuleForThinLTO(Mod, CombinedIndex); 505 506 dropDeadSymbols(Mod, DefinedGlobals, CombinedIndex); 507 508 thinLTOResolvePrevailingInModule(Mod, DefinedGlobals); 509 510 if (Conf.PostPromoteModuleHook && !Conf.PostPromoteModuleHook(Task, Mod)) 511 return finalizeOptimizationRemarks(std::move(DiagnosticOutputFile)); 512 513 if (!DefinedGlobals.empty()) 514 thinLTOInternalizeModule(Mod, DefinedGlobals); 515 516 if (Conf.PostInternalizeModuleHook && 517 !Conf.PostInternalizeModuleHook(Task, Mod)) 518 return finalizeOptimizationRemarks(std::move(DiagnosticOutputFile)); 519 520 auto ModuleLoader = [&](StringRef Identifier) { 521 assert(Mod.getContext().isODRUniquingDebugTypes() && 522 "ODR Type uniquing should be enabled on the context"); 523 auto I = ModuleMap.find(Identifier); 524 assert(I != ModuleMap.end()); 525 return I->second.getLazyModule(Mod.getContext(), 526 /*ShouldLazyLoadMetadata=*/true, 527 /*IsImporting*/ true); 528 }; 529 530 FunctionImporter Importer(CombinedIndex, ModuleLoader); 531 if (Error Err = Importer.importFunctions(Mod, ImportList).takeError()) 532 return Err; 533 534 if (Conf.PostImportModuleHook && !Conf.PostImportModuleHook(Task, Mod)) 535 return finalizeOptimizationRemarks(std::move(DiagnosticOutputFile)); 536 537 if (!opt(Conf, TM.get(), Task, Mod, /*IsThinLTO=*/true, 538 /*ExportSummary=*/nullptr, /*ImportSummary=*/&CombinedIndex)) 539 return finalizeOptimizationRemarks(std::move(DiagnosticOutputFile)); 540 541 codegen(Conf, TM.get(), AddStream, Task, Mod); 542 return finalizeOptimizationRemarks(std::move(DiagnosticOutputFile)); 543 } 544