llvm/tools/opt/opt.cpp

   1 //===- opt.cpp - The LLVM Modular Optimizer -------------------------------===//
   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 // Optimizations may be specified an arbitrary number of times on the command
  10 // line, They are run in the order specified.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "NewPMDriver.h"
  15 #include "llvm/Analysis/CallGraph.h"
  16 #include "llvm/Analysis/CallGraphSCCPass.h"
  17 #include "llvm/Analysis/LoopPass.h"
  18 #include "llvm/Analysis/RegionPass.h"
  19 #include "llvm/Analysis/TargetLibraryInfo.h"
  20 #include "llvm/Analysis/TargetTransformInfo.h"
  21 #include "llvm/AsmParser/Parser.h"
  22 #include "llvm/CodeGen/CommandFlags.h"
  23 #include "llvm/CodeGen/TargetPassConfig.h"
  24 #include "llvm/Config/llvm-config.h"
  25 #include "llvm/IR/DataLayout.h"
  26 #include "llvm/IR/DebugInfo.h"
  27 #include "llvm/IR/LLVMContext.h"
  28 #include "llvm/IR/LLVMRemarkStreamer.h"
  29 #include "llvm/IR/LegacyPassManager.h"
  30 #include "llvm/IR/LegacyPassNameParser.h"
  31 #include "llvm/IR/Module.h"
  32 #include "llvm/IR/ModuleSummaryIndex.h"
  33 #include "llvm/IR/Verifier.h"
  34 #include "llvm/IRReader/IRReader.h"
  35 #include "llvm/InitializePasses.h"
  36 #include "llvm/LinkAllIR.h"
  37 #include "llvm/LinkAllPasses.h"
  38 #include "llvm/MC/TargetRegistry.h"
  39 #include "llvm/Passes/PassPlugin.h"
  40 #include "llvm/Remarks/HotnessThresholdParser.h"
  41 #include "llvm/Support/Debug.h"
  42 #include "llvm/Support/ErrorHandling.h"
  43 #include "llvm/Support/FileSystem.h"
  44 #include "llvm/Support/InitLLVM.h"
  45 #include "llvm/Support/PluginLoader.h"
  46 #include "llvm/Support/SourceMgr.h"
  47 #include "llvm/Support/SystemUtils.h"
  48 #include "llvm/Support/TargetSelect.h"
  49 #include "llvm/Support/ToolOutputFile.h"
  50 #include "llvm/Support/YAMLTraits.h"
  51 #include "llvm/Target/TargetMachine.h"
  52 #include "llvm/TargetParser/Host.h"
  53 #include "llvm/TargetParser/SubtargetFeature.h"
  54 #include "llvm/TargetParser/Triple.h"
  55 #include "llvm/Transforms/IPO/WholeProgramDevirt.h"
  56 #include "llvm/Transforms/Utils/Cloning.h"
  57 #include "llvm/Transforms/Utils/Debugify.h"
  58 #include <algorithm>
  59 #include <memory>
  60 #include <optional>
  61 using namespace llvm;
  62 using namespace opt_tool;
  63
  64 static codegen::RegisterCodeGenFlags CFG;
  65
  66 // The OptimizationList is automatically populated with registered Passes by the
  67 // PassNameParser.
  68 static cl::list<const PassInfo *, bool, PassNameParser> PassList(cl::desc(
  69     "Optimizations available (use '-passes=' for the new pass manager)"));
  70
  71 static cl::opt<bool> EnableLegacyPassManager(
  72     "bugpoint-enable-legacy-pm",
  73     cl::desc(
  74         "Enable the legacy pass manager. This is strictly for bugpoint "
  75         "due to it not working with the new PM, please do not use otherwise."),
  76     cl::init(false));
  77
  78 // This flag specifies a textual description of the optimization pass pipeline
  79 // to run over the module. This flag switches opt to use the new pass manager
  80 // infrastructure, completely disabling all of the flags specific to the old
  81 // pass management.
  82 static cl::opt<std::string> PassPipeline(
  83     "passes",
  84     cl::desc(
  85         "A textual description of the pass pipeline. To have analysis passes "
  86         "available before a certain pass, add 'require<foo-analysis>'."));
  87 static cl::alias PassPipeline2("p", cl::aliasopt(PassPipeline),
  88                                    cl::desc("Alias for -passes"));
  89
  90 static cl::opt<bool> PrintPasses("print-passes",
  91                                  cl::desc("Print available passes that can be "
  92                                           "specified in -passes=foo and exit"));
  93
  94 static cl::opt<std::string>
  95 InputFilename(cl::Positional, cl::desc("<input bitcode file>"),
  96     cl::init("-"), cl::value_desc("filename"));
  97
  98 static cl::opt<std::string>
  99 OutputFilename("o", cl::desc("Override output filename"),
 100                cl::value_desc("filename"));
 101
 102 static cl::opt<bool>
 103 Force("f", cl::desc("Enable binary output on terminals"));
 104
 105 static cl::opt<bool>
 106 NoOutput("disable-output",
 107          cl::desc("Do not write result bitcode file"), cl::Hidden);
 108
 109 static cl::opt<bool>
 110 OutputAssembly("S", cl::desc("Write output as LLVM assembly"));
 111
 112 static cl::opt<bool>
 113     OutputThinLTOBC("thinlto-bc",
 114                     cl::desc("Write output as ThinLTO-ready bitcode"));
 115
 116 static cl::opt<bool>
 117     SplitLTOUnit("thinlto-split-lto-unit",
 118                  cl::desc("Enable splitting of a ThinLTO LTOUnit"));
 119
 120 static cl::opt<bool>
 121     UnifiedLTO("unified-lto",
 122                cl::desc("Use unified LTO piplines. Ignored unless -thinlto-bc "
 123                         "is also specified."),
 124                cl::Hidden, cl::init(false));
 125
 126 static cl::opt<std::string> ThinLinkBitcodeFile(
 127     "thin-link-bitcode-file", cl::value_desc("filename"),
 128     cl::desc(
 129         "A file in which to write minimized bitcode for the thin link only"));
 130
 131 static cl::opt<bool>
 132 NoVerify("disable-verify", cl::desc("Do not run the verifier"), cl::Hidden);
 133
 134 static cl::opt<bool> NoUpgradeDebugInfo("disable-upgrade-debug-info",
 135                                         cl::desc("Generate invalid output"),
 136                                         cl::ReallyHidden);
 137
 138 static cl::opt<bool> VerifyEach("verify-each",
 139                                 cl::desc("Verify after each transform"));
 140
 141 static cl::opt<bool>
 142     DisableDITypeMap("disable-debug-info-type-map",
 143                      cl::desc("Don't use a uniquing type map for debug info"));
 144
 145 static cl::opt<bool>
 146 StripDebug("strip-debug",
 147            cl::desc("Strip debugger symbol info from translation unit"));
 148
 149 static cl::opt<bool>
 150     StripNamedMetadata("strip-named-metadata",
 151                        cl::desc("Strip module-level named metadata"));
 152
 153 static cl::opt<bool>
 154     OptLevelO0("O0", cl::desc("Optimization level 0. Similar to clang -O0. "
 155                               "Same as -passes='default<O0>'"));
 156
 157 static cl::opt<bool>
 158     OptLevelO1("O1", cl::desc("Optimization level 1. Similar to clang -O1. "
 159                               "Same as -passes='default<O1>'"));
 160
 161 static cl::opt<bool>
 162     OptLevelO2("O2", cl::desc("Optimization level 2. Similar to clang -O2. "
 163                               "Same as -passes='default<O2>'"));
 164
 165 static cl::opt<bool>
 166     OptLevelOs("Os", cl::desc("Like -O2 but size-conscious. Similar to clang "
 167                               "-Os. Same as -passes='default<Os>'"));
 168
 169 static cl::opt<bool> OptLevelOz(
 170     "Oz",
 171     cl::desc("Like -O2 but optimize for code size above all else. Similar to "
 172              "clang -Oz. Same as -passes='default<Oz>'"));
 173
 174 static cl::opt<bool>
 175     OptLevelO3("O3", cl::desc("Optimization level 3. Similar to clang -O3. "
 176                               "Same as -passes='default<O3>'"));
 177
 178 static cl::opt<unsigned> CodeGenOptLevelCL(
 179     "codegen-opt-level",
 180     cl::desc("Override optimization level for codegen hooks, legacy PM only"));
 181
 182 static cl::opt<std::string>
 183 TargetTriple("mtriple", cl::desc("Override target triple for module"));
 184
 185 static cl::opt<bool> EmitSummaryIndex("module-summary",
 186                                       cl::desc("Emit module summary index"),
 187                                       cl::init(false));
 188
 189 static cl::opt<bool> EmitModuleHash("module-hash", cl::desc("Emit module hash"),
 190                                     cl::init(false));
 191
 192 static cl::opt<bool>
 193 DisableSimplifyLibCalls("disable-simplify-libcalls",
 194                         cl::desc("Disable simplify-libcalls"));
 195
 196 static cl::list<std::string> DisableBuiltins(
 197     "disable-builtin",
 198     cl::desc("Disable specific target library builtin function"));
 199
 200 static cl::opt<bool> EnableDebugify(
 201     "enable-debugify",
 202     cl::desc(
 203         "Start the pipeline with debugify and end it with check-debugify"));
 204
 205 static cl::opt<bool> VerifyDebugInfoPreserve(
 206     "verify-debuginfo-preserve",
 207     cl::desc("Start the pipeline with collecting and end it with checking of "
 208              "debug info preservation."));
 209
 210 static cl::opt<std::string> ClDataLayout("data-layout",
 211                                          cl::desc("data layout string to use"),
 212                                          cl::value_desc("layout-string"),
 213                                          cl::init(""));
 214
 215 static cl::opt<bool> PreserveBitcodeUseListOrder(
 216     "preserve-bc-uselistorder",
 217     cl::desc("Preserve use-list order when writing LLVM bitcode."),
 218     cl::init(true), cl::Hidden);
 219
 220 static cl::opt<bool> PreserveAssemblyUseListOrder(
 221     "preserve-ll-uselistorder",
 222     cl::desc("Preserve use-list order when writing LLVM assembly."),
 223     cl::init(false), cl::Hidden);
 224
 225 static cl::opt<bool> RunTwice("run-twice",
 226                               cl::desc("Run all passes twice, re-using the "
 227                                        "same pass manager (legacy PM only)."),
 228                               cl::init(false), cl::Hidden);
 229
 230 static cl::opt<bool> DiscardValueNames(
 231     "discard-value-names",
 232     cl::desc("Discard names from Value (other than GlobalValue)."),
 233     cl::init(false), cl::Hidden);
 234
 235 static cl::opt<bool> TimeTrace(
 236     "time-trace",
 237     cl::desc("Record time trace"));
 238
 239 static cl::opt<unsigned> TimeTraceGranularity(
 240     "time-trace-granularity",
 241     cl::desc("Minimum time granularity (in microseconds) traced by time profiler"),
 242     cl::init(500), cl::Hidden);
 243
 244 static cl::opt<std::string>
 245     TimeTraceFile("time-trace-file",
 246                     cl::desc("Specify time trace file destination"),
 247                     cl::value_desc("filename"));
 248
 249 static cl::opt<bool> RemarksWithHotness(
 250     "pass-remarks-with-hotness",
 251     cl::desc("With PGO, include profile count in optimization remarks"),
 252     cl::Hidden);
 253
 254 static cl::opt<std::optional<uint64_t>, false, remarks::HotnessThresholdParser>
 255     RemarksHotnessThreshold(
 256         "pass-remarks-hotness-threshold",
 257         cl::desc("Minimum profile count required for "
 258                  "an optimization remark to be output. "
 259                  "Use 'auto' to apply the threshold from profile summary"),
 260         cl::value_desc("N or 'auto'"), cl::init(0), cl::Hidden);
 261
 262 static cl::opt<std::string>
 263     RemarksFilename("pass-remarks-output",
 264                     cl::desc("Output filename for pass remarks"),
 265                     cl::value_desc("filename"));
 266
 267 static cl::opt<std::string>
 268     RemarksPasses("pass-remarks-filter",
 269                   cl::desc("Only record optimization remarks from passes whose "
 270                            "names match the given regular expression"),
 271                   cl::value_desc("regex"));
 272
 273 static cl::opt<std::string> RemarksFormat(
 274     "pass-remarks-format",
 275     cl::desc("The format used for serializing remarks (default: YAML)"),
 276     cl::value_desc("format"), cl::init("yaml"));
 277
 278 static cl::list<std::string>
 279     PassPlugins("load-pass-plugin",
 280                 cl::desc("Load passes from plugin library"));
 281
 282 //===----------------------------------------------------------------------===//
 283 // CodeGen-related helper functions.
 284 //
 285
 286 static CodeGenOptLevel GetCodeGenOptLevel() {
 287   return static_cast<CodeGenOptLevel>(unsigned(CodeGenOptLevelCL));
 288 }
 289
 290 struct TimeTracerRAII {
 291   TimeTracerRAII(StringRef ProgramName) {
 292     if (TimeTrace)
 293       timeTraceProfilerInitialize(TimeTraceGranularity, ProgramName);
 294   }
 295   ~TimeTracerRAII() {
 296     if (TimeTrace) {
 297       if (auto E = timeTraceProfilerWrite(TimeTraceFile, OutputFilename)) {
 298         handleAllErrors(std::move(E), [&](const StringError &SE) {
 299           errs() << SE.getMessage() << "\n";
 300         });
 301         return;
 302       }
 303       timeTraceProfilerCleanup();
 304     }
 305   }
 306 };
 307
 308 // For use in NPM transition. Currently this contains most codegen-specific
 309 // passes. Remove passes from here when porting to the NPM.
 310 // TODO: use a codegen version of PassRegistry.def/PassBuilder::is*Pass() once
 311 // it exists.
 312 static bool shouldPinPassToLegacyPM(StringRef Pass) {
 313   std::vector<StringRef> PassNameExactToIgnore = {
 314       "nvvm-reflect",
 315       "nvvm-intr-range",
 316       "amdgpu-simplifylib",
 317       "amdgpu-image-intrinsic-opt",
 318       "amdgpu-usenative",
 319       "amdgpu-promote-alloca",
 320       "amdgpu-promote-alloca-to-vector",
 321       "amdgpu-lower-kernel-attributes",
 322       "amdgpu-propagate-attributes-early",
 323       "amdgpu-propagate-attributes-late",
 324       "amdgpu-unify-metadata",
 325       "amdgpu-printf-runtime-binding",
 326       "amdgpu-always-inline"};
 327   if (llvm::is_contained(PassNameExactToIgnore, Pass))
 328     return false;
 329
 330   std::vector<StringRef> PassNamePrefix = {
 331       "x86-",    "xcore-", "wasm-",  "systemz-", "ppc-",    "nvvm-",
 332       "nvptx-",  "mips-",  "lanai-", "hexagon-", "bpf-",    "avr-",
 333       "thumb2-", "arm-",   "si-",    "gcn-",     "amdgpu-", "aarch64-",
 334       "amdgcn-", "polly-", "riscv-", "dxil-"};
 335   std::vector<StringRef> PassNameContain = {"ehprepare"};
 336   std::vector<StringRef> PassNameExact = {
 337       "safe-stack",
 338       "cost-model",
 339       "codegenprepare",
 340       "interleaved-load-combine",
 341       "unreachableblockelim",
 342       "verify-safepoint-ir",
 343       "atomic-expand",
 344       "expandvp",
 345       "mve-tail-predication",
 346       "interleaved-access",
 347       "global-merge",
 348       "pre-isel-intrinsic-lowering",
 349       "expand-reductions",
 350       "indirectbr-expand",
 351       "generic-to-nvvm",
 352       "expandmemcmp",
 353       "loop-reduce",
 354       "lower-amx-type",
 355       "lower-amx-intrinsics",
 356       "polyhedral-info",
 357       "print-polyhedral-info",
 358       "replace-with-veclib",
 359       "jmc-instrument",
 360       "dot-regions",
 361       "dot-regions-only",
 362       "view-regions",
 363       "view-regions-only",
 364       "select-optimize",
 365       "expand-large-div-rem",
 366       "structurizecfg",
 367       "fix-irreducible",
 368       "expand-large-fp-convert",
 369       "callbrprepare",
 370   };
 371   for (const auto &P : PassNamePrefix)
 372     if (Pass.startswith(P))
 373       return true;
 374   for (const auto &P : PassNameContain)
 375     if (Pass.contains(P))
 376       return true;
 377   return llvm::is_contained(PassNameExact, Pass);
 378 }
 379
 380 // For use in NPM transition.
 381 static bool shouldForceLegacyPM() {
 382   for (const auto &P : PassList) {
 383     StringRef Arg = P->getPassArgument();
 384     if (shouldPinPassToLegacyPM(Arg))
 385       return true;
 386   }
 387   return false;
 388 }
 389
 390 //===----------------------------------------------------------------------===//
 391 // main for opt
 392 //
 393 int main(int argc, char **argv) {
 394   InitLLVM X(argc, argv);
 395
 396   // Enable debug stream buffering.
 397   EnableDebugBuffering = true;
 398
 399   InitializeAllTargets();
 400   InitializeAllTargetMCs();
 401   InitializeAllAsmPrinters();
 402   InitializeAllAsmParsers();
 403
 404   // Initialize passes
 405   PassRegistry &Registry = *PassRegistry::getPassRegistry();
 406   initializeCore(Registry);
 407   initializeScalarOpts(Registry);
 408   initializeVectorization(Registry);
 409   initializeIPO(Registry);
 410   initializeAnalysis(Registry);
 411   initializeTransformUtils(Registry);
 412   initializeInstCombine(Registry);
 413   initializeTarget(Registry);
 414   // For codegen passes, only passes that do IR to IR transformation are
 415   // supported.
 416   initializeExpandLargeDivRemLegacyPassPass(Registry);
 417   initializeExpandLargeFpConvertLegacyPassPass(Registry);
 418   initializeExpandMemCmpPassPass(Registry);
 419   initializeScalarizeMaskedMemIntrinLegacyPassPass(Registry);
 420   initializeSelectOptimizePass(Registry);
 421   initializeCallBrPreparePass(Registry);
 422   initializeCodeGenPreparePass(Registry);
 423   initializeAtomicExpandPass(Registry);
 424   initializeWinEHPreparePass(Registry);
 425   initializeDwarfEHPrepareLegacyPassPass(Registry);
 426   initializeSafeStackLegacyPassPass(Registry);
 427   initializeSjLjEHPreparePass(Registry);
 428   initializePreISelIntrinsicLoweringLegacyPassPass(Registry);
 429   initializeGlobalMergePass(Registry);
 430   initializeIndirectBrExpandPassPass(Registry);
 431   initializeInterleavedLoadCombinePass(Registry);
 432   initializeInterleavedAccessPass(Registry);
 433   initializeUnreachableBlockElimLegacyPassPass(Registry);
 434   initializeExpandReductionsPass(Registry);
 435   initializeExpandVectorPredicationPass(Registry);
 436   initializeWasmEHPreparePass(Registry);
 437   initializeWriteBitcodePassPass(Registry);
 438   initializeReplaceWithVeclibLegacyPass(Registry);
 439   initializeJMCInstrumenterPass(Registry);
 440
 441   SmallVector<PassPlugin, 1> PluginList;
 442   PassPlugins.setCallback([&](const std::string &PluginPath) {
 443     auto Plugin = PassPlugin::Load(PluginPath);
 444     if (!Plugin)
 445       report_fatal_error(Plugin.takeError(), /*gen_crash_diag=*/false);
 446     PluginList.emplace_back(Plugin.get());
 447   });
 448
 449   // Register the Target and CPU printer for --version.
 450   cl::AddExtraVersionPrinter(sys::printDefaultTargetAndDetectedCPU);
 451
 452   cl::ParseCommandLineOptions(argc, argv,
 453     "llvm .bc -> .bc modular optimizer and analysis printer\n");
 454
 455   LLVMContext Context;
 456
 457   // TODO: remove shouldForceLegacyPM().
 458   const bool UseNPM = (!EnableLegacyPassManager && !shouldForceLegacyPM()) ||
 459                       PassPipeline.getNumOccurrences() > 0;
 460
 461   if (UseNPM && !PassList.empty()) {
 462     errs() << "The `opt -passname` syntax for the new pass manager is "
 463               "not supported, please use `opt -passes=<pipeline>` (or the `-p` "
 464               "alias for a more concise version).\n";
 465     errs() << "See https://llvm.org/docs/NewPassManager.html#invoking-opt "
 466               "for more details on the pass pipeline syntax.\n\n";
 467     return 1;
 468   }
 469
 470   if (!UseNPM && PluginList.size()) {
 471     errs() << argv[0] << ": " << PassPlugins.ArgStr
 472            << " specified with legacy PM.\n";
 473     return 1;
 474   }
 475
 476   // FIXME: once the legacy PM code is deleted, move runPassPipeline() here and
 477   // construct the PassBuilder before parsing IR so we can reuse the same
 478   // PassBuilder for print passes.
 479   if (PrintPasses) {
 480     printPasses(outs());
 481     return 0;
 482   }
 483
 484   TimeTracerRAII TimeTracer(argv[0]);
 485
 486   SMDiagnostic Err;
 487
 488   Context.setDiscardValueNames(DiscardValueNames);
 489   if (!DisableDITypeMap)
 490     Context.enableDebugTypeODRUniquing();
 491
 492   Expected<std::unique_ptr<ToolOutputFile>> RemarksFileOrErr =
 493       setupLLVMOptimizationRemarks(Context, RemarksFilename, RemarksPasses,
 494                                    RemarksFormat, RemarksWithHotness,
 495                                    RemarksHotnessThreshold);
 496   if (Error E = RemarksFileOrErr.takeError()) {
 497     errs() << toString(std::move(E)) << '\n';
 498     return 1;
 499   }
 500   std::unique_ptr<ToolOutputFile> RemarksFile = std::move(*RemarksFileOrErr);
 501
 502   // Load the input module...
 503   auto SetDataLayout = [&](StringRef IRTriple,
 504                            StringRef IRLayout) -> std::optional<std::string> {
 505     // Data layout specified on the command line has the highest priority.
 506     if (!ClDataLayout.empty())
 507       return ClDataLayout;
 508     // If an explicit data layout is already defined in the IR, don't infer.
 509     if (!IRLayout.empty())
 510       return std::nullopt;
 511
 512     // If an explicit triple was specified (either in the IR or on the
 513     // command line), use that to infer the default data layout. However, the
 514     // command line target triple should override the IR file target triple.
 515     std::string TripleStr =
 516         TargetTriple.empty() ? IRTriple.str() : Triple::normalize(TargetTriple);
 517     // If the triple string is still empty, we don't fall back to
 518     // sys::getDefaultTargetTriple() since we do not want to have differing
 519     // behaviour dependent on the configured default triple. Therefore, if the
 520     // user did not pass -mtriple or define an explicit triple/datalayout in
 521     // the IR, we should default to an empty (default) DataLayout.
 522     if (TripleStr.empty())
 523       return std::nullopt;
 524     // Otherwise we infer the DataLayout from the target machine.
 525     Expected<std::unique_ptr<TargetMachine>> ExpectedTM =
 526         codegen::createTargetMachineForTriple(TripleStr, GetCodeGenOptLevel());
 527     if (!ExpectedTM) {
 528       errs() << argv[0] << ": warning: failed to infer data layout: "
 529              << toString(ExpectedTM.takeError()) << "\n";
 530       return std::nullopt;
 531     }
 532     return (*ExpectedTM)->createDataLayout().getStringRepresentation();
 533   };
 534   std::unique_ptr<Module> M;
 535   if (NoUpgradeDebugInfo)
 536     M = parseAssemblyFileWithIndexNoUpgradeDebugInfo(
 537             InputFilename, Err, Context, nullptr, SetDataLayout)
 538             .Mod;
 539   else
 540     M = parseIRFile(InputFilename, Err, Context,
 541                     ParserCallbacks(SetDataLayout));
 542
 543   if (!M) {
 544     Err.print(argv[0], errs());
 545     return 1;
 546   }
 547
 548   // Strip debug info before running the verifier.
 549   if (StripDebug)
 550     StripDebugInfo(*M);
 551
 552   // Erase module-level named metadata, if requested.
 553   if (StripNamedMetadata) {
 554     while (!M->named_metadata_empty()) {
 555       NamedMDNode *NMD = &*M->named_metadata_begin();
 556       M->eraseNamedMetadata(NMD);
 557     }
 558   }
 559
 560   // If we are supposed to override the target triple, do so now.
 561   if (!TargetTriple.empty())
 562     M->setTargetTriple(Triple::normalize(TargetTriple));
 563
 564   // Immediately run the verifier to catch any problems before starting up the
 565   // pass pipelines.  Otherwise we can crash on broken code during
 566   // doInitialization().
 567   if (!NoVerify && verifyModule(*M, &errs())) {
 568     errs() << argv[0] << ": " << InputFilename
 569            << ": error: input module is broken!\n";
 570     return 1;
 571   }
 572
 573   // Enable testing of whole program devirtualization on this module by invoking
 574   // the facility for updating public visibility to linkage unit visibility when
 575   // specified by an internal option. This is normally done during LTO which is
 576   // not performed via opt.
 577   updateVCallVisibilityInModule(
 578       *M,
 579       /*WholeProgramVisibilityEnabledInLTO=*/false,
 580       // FIXME: These need linker information via a
 581       // TBD new interface.
 582       /*DynamicExportSymbols=*/{},
 583       /*ValidateAllVtablesHaveTypeInfos=*/false,
 584       /*IsVisibleToRegularObj=*/[](StringRef) { return true; });
 585
 586   // Figure out what stream we are supposed to write to...
 587   std::unique_ptr<ToolOutputFile> Out;
 588   std::unique_ptr<ToolOutputFile> ThinLinkOut;
 589   if (NoOutput) {
 590     if (!OutputFilename.empty())
 591       errs() << "WARNING: The -o (output filename) option is ignored when\n"
 592                 "the --disable-output option is used.\n";
 593   } else {
 594     // Default to standard output.
 595     if (OutputFilename.empty())
 596       OutputFilename = "-";
 597
 598     std::error_code EC;
 599     sys::fs::OpenFlags Flags =
 600         OutputAssembly ? sys::fs::OF_TextWithCRLF : sys::fs::OF_None;
 601     Out.reset(new ToolOutputFile(OutputFilename, EC, Flags));
 602     if (EC) {
 603       errs() << EC.message() << '\n';
 604       return 1;
 605     }
 606
 607     if (!ThinLinkBitcodeFile.empty()) {
 608       ThinLinkOut.reset(
 609           new ToolOutputFile(ThinLinkBitcodeFile, EC, sys::fs::OF_None));
 610       if (EC) {
 611         errs() << EC.message() << '\n';
 612         return 1;
 613       }
 614     }
 615   }
 616
 617   Triple ModuleTriple(M->getTargetTriple());
 618   std::string CPUStr, FeaturesStr;
 619   std::unique_ptr<TargetMachine> TM;
 620   if (ModuleTriple.getArch()) {
 621     CPUStr = codegen::getCPUStr();
 622     FeaturesStr = codegen::getFeaturesStr();
 623     Expected<std::unique_ptr<TargetMachine>> ExpectedTM =
 624         codegen::createTargetMachineForTriple(ModuleTriple.str(),
 625                                               GetCodeGenOptLevel());
 626     if (auto E = ExpectedTM.takeError()) {
 627       errs() << argv[0] << ": WARNING: failed to create target machine for '"
 628              << ModuleTriple.str() << "': " << toString(std::move(E)) << "\n";
 629     } else {
 630       TM = std::move(*ExpectedTM);
 631     }
 632   } else if (ModuleTriple.getArchName() != "unknown" &&
 633              ModuleTriple.getArchName() != "") {
 634     errs() << argv[0] << ": unrecognized architecture '"
 635            << ModuleTriple.getArchName() << "' provided.\n";
 636     return 1;
 637   }
 638
 639   // Override function attributes based on CPUStr, FeaturesStr, and command line
 640   // flags.
 641   codegen::setFunctionAttributes(CPUStr, FeaturesStr, *M);
 642
 643   // If the output is set to be emitted to standard out, and standard out is a
 644   // console, print out a warning message and refuse to do it.  We don't
 645   // impress anyone by spewing tons of binary goo to a terminal.
 646   if (!Force && !NoOutput && !OutputAssembly)
 647     if (CheckBitcodeOutputToConsole(Out->os()))
 648       NoOutput = true;
 649
 650   if (OutputThinLTOBC) {
 651     M->addModuleFlag(Module::Error, "EnableSplitLTOUnit", SplitLTOUnit);
 652     if (UnifiedLTO)
 653       M->addModuleFlag(Module::Error, "UnifiedLTO", 1);
 654   }
 655
 656   // Add an appropriate TargetLibraryInfo pass for the module's triple.
 657   TargetLibraryInfoImpl TLII(ModuleTriple);
 658
 659   // The -disable-simplify-libcalls flag actually disables all builtin optzns.
 660   if (DisableSimplifyLibCalls)
 661     TLII.disableAllFunctions();
 662   else {
 663     // Disable individual builtin functions in TargetLibraryInfo.
 664     LibFunc F;
 665     for (auto &FuncName : DisableBuiltins)
 666       if (TLII.getLibFunc(FuncName, F))
 667         TLII.setUnavailable(F);
 668       else {
 669         errs() << argv[0] << ": cannot disable nonexistent builtin function "
 670                << FuncName << '\n';
 671         return 1;
 672       }
 673   }
 674
 675   if (UseNPM) {
 676     if (legacy::debugPassSpecified()) {
 677       errs() << "-debug-pass does not work with the new PM, either use "
 678                 "-debug-pass-manager, or use the legacy PM\n";
 679       return 1;
 680     }
 681     auto NumOLevel = OptLevelO0 + OptLevelO1 + OptLevelO2 + OptLevelO3 +
 682                      OptLevelOs + OptLevelOz;
 683     if (NumOLevel > 1) {
 684       errs() << "Cannot specify multiple -O#\n";
 685       return 1;
 686     }
 687     if (NumOLevel > 0 && (PassPipeline.getNumOccurrences() > 0)) {
 688       errs() << "Cannot specify -O# and --passes=/--foo-pass, use "
 689                 "-passes='default<O#>,other-pass'\n";
 690       return 1;
 691     }
 692     std::string Pipeline = PassPipeline;
 693
 694     if (OptLevelO0)
 695       Pipeline = "default<O0>";
 696     if (OptLevelO1)
 697       Pipeline = "default<O1>";
 698     if (OptLevelO2)
 699       Pipeline = "default<O2>";
 700     if (OptLevelO3)
 701       Pipeline = "default<O3>";
 702     if (OptLevelOs)
 703       Pipeline = "default<Os>";
 704     if (OptLevelOz)
 705       Pipeline = "default<Oz>";
 706     OutputKind OK = OK_NoOutput;
 707     if (!NoOutput)
 708       OK = OutputAssembly
 709                ? OK_OutputAssembly
 710                : (OutputThinLTOBC ? OK_OutputThinLTOBitcode : OK_OutputBitcode);
 711
 712     VerifierKind VK = VK_VerifyOut;
 713     if (NoVerify)
 714       VK = VK_NoVerifier;
 715     else if (VerifyEach)
 716       VK = VK_VerifyEachPass;
 717
 718     // The user has asked to use the new pass manager and provided a pipeline
 719     // string. Hand off the rest of the functionality to the new code for that
 720     // layer.
 721     return runPassPipeline(argv[0], *M, TM.get(), &TLII, Out.get(),
 722                            ThinLinkOut.get(), RemarksFile.get(), Pipeline,
 723                            PluginList, OK, VK, PreserveAssemblyUseListOrder,
 724                            PreserveBitcodeUseListOrder, EmitSummaryIndex,
 725                            EmitModuleHash, EnableDebugify,
 726                            VerifyDebugInfoPreserve, UnifiedLTO)
 727                ? 0
 728                : 1;
 729   }
 730
 731   if (OptLevelO0 || OptLevelO1 || OptLevelO2 || OptLevelOs || OptLevelOz ||
 732       OptLevelO3) {
 733     errs() << "Cannot use -O# with legacy PM.\n";
 734     return 1;
 735   }
 736   if (EmitSummaryIndex) {
 737     errs() << "Cannot use -module-summary with legacy PM.\n";
 738     return 1;
 739   }
 740   if (EmitModuleHash) {
 741     errs() << "Cannot use -module-hash with legacy PM.\n";
 742     return 1;
 743   }
 744   if (OutputThinLTOBC) {
 745     errs() << "Cannot use -thinlto-bc with legacy PM.\n";
 746     return 1;
 747   }
 748   // Create a PassManager to hold and optimize the collection of passes we are
 749   // about to build. If the -debugify-each option is set, wrap each pass with
 750   // the (-check)-debugify passes.
 751   DebugifyCustomPassManager Passes;
 752   DebugifyStatsMap DIStatsMap;
 753   DebugInfoPerPass DebugInfoBeforePass;
 754   if (DebugifyEach) {
 755     Passes.setDebugifyMode(DebugifyMode::SyntheticDebugInfo);
 756     Passes.setDIStatsMap(DIStatsMap);
 757   } else if (VerifyEachDebugInfoPreserve) {
 758     Passes.setDebugifyMode(DebugifyMode::OriginalDebugInfo);
 759     Passes.setDebugInfoBeforePass(DebugInfoBeforePass);
 760     if (!VerifyDIPreserveExport.empty())
 761       Passes.setOrigDIVerifyBugsReportFilePath(VerifyDIPreserveExport);
 762   }
 763
 764   bool AddOneTimeDebugifyPasses =
 765       (EnableDebugify && !DebugifyEach) ||
 766       (VerifyDebugInfoPreserve && !VerifyEachDebugInfoPreserve);
 767
 768   Passes.add(new TargetLibraryInfoWrapperPass(TLII));
 769
 770   // Add internal analysis passes from the target machine.
 771   Passes.add(createTargetTransformInfoWrapperPass(TM ? TM->getTargetIRAnalysis()
 772                                                      : TargetIRAnalysis()));
 773
 774   if (AddOneTimeDebugifyPasses) {
 775     if (EnableDebugify) {
 776       Passes.setDIStatsMap(DIStatsMap);
 777       Passes.add(createDebugifyModulePass());
 778     } else if (VerifyDebugInfoPreserve) {
 779       Passes.setDebugInfoBeforePass(DebugInfoBeforePass);
 780       Passes.add(createDebugifyModulePass(
 781           DebugifyMode::OriginalDebugInfo, "",
 782           &(Passes.getDebugInfoPerPass())));
 783     }
 784   }
 785
 786   if (TM) {
 787     // FIXME: We should dyn_cast this when supported.
 788     auto &LTM = static_cast<LLVMTargetMachine &>(*TM);
 789     Pass *TPC = LTM.createPassConfig(Passes);
 790     Passes.add(TPC);
 791   }
 792
 793   // Create a new optimization pass for each one specified on the command line
 794   for (unsigned i = 0; i < PassList.size(); ++i) {
 795     const PassInfo *PassInf = PassList[i];
 796     if (PassInf->getNormalCtor()) {
 797       Pass *P = PassInf->getNormalCtor()();
 798       if (P) {
 799         // Add the pass to the pass manager.
 800         Passes.add(P);
 801         // If we are verifying all of the intermediate steps, add the verifier.
 802         if (VerifyEach)
 803           Passes.add(createVerifierPass());
 804       }
 805     } else
 806       errs() << argv[0] << ": cannot create pass: "
 807              << PassInf->getPassName() << "\n";
 808   }
 809
 810   // Check that the module is well formed on completion of optimization
 811   if (!NoVerify && !VerifyEach)
 812     Passes.add(createVerifierPass());
 813
 814   if (AddOneTimeDebugifyPasses) {
 815     if (EnableDebugify)
 816       Passes.add(createCheckDebugifyModulePass(false));
 817     else if (VerifyDebugInfoPreserve) {
 818       if (!VerifyDIPreserveExport.empty())
 819         Passes.setOrigDIVerifyBugsReportFilePath(VerifyDIPreserveExport);
 820       Passes.add(createCheckDebugifyModulePass(
 821           false, "", nullptr, DebugifyMode::OriginalDebugInfo,
 822           &(Passes.getDebugInfoPerPass()), VerifyDIPreserveExport));
 823     }
 824   }
 825
 826   // In run twice mode, we want to make sure the output is bit-by-bit
 827   // equivalent if we run the pass manager again, so setup two buffers and
 828   // a stream to write to them. Note that llc does something similar and it
 829   // may be worth to abstract this out in the future.
 830   SmallVector<char, 0> Buffer;
 831   SmallVector<char, 0> FirstRunBuffer;
 832   std::unique_ptr<raw_svector_ostream> BOS;
 833   raw_ostream *OS = nullptr;
 834
 835   const bool ShouldEmitOutput = !NoOutput;
 836
 837   // Write bitcode or assembly to the output as the last step...
 838   if (ShouldEmitOutput || RunTwice) {
 839     assert(Out);
 840     OS = &Out->os();
 841     if (RunTwice) {
 842       BOS = std::make_unique<raw_svector_ostream>(Buffer);
 843       OS = BOS.get();
 844     }
 845     if (OutputAssembly)
 846       Passes.add(createPrintModulePass(*OS, "", PreserveAssemblyUseListOrder));
 847     else
 848       Passes.add(createBitcodeWriterPass(*OS, PreserveBitcodeUseListOrder));
 849   }
 850
 851   // Before executing passes, print the final values of the LLVM options.
 852   cl::PrintOptionValues();
 853
 854   if (!RunTwice) {
 855     // Now that we have all of the passes ready, run them.
 856     Passes.run(*M);
 857   } else {
 858     // If requested, run all passes twice with the same pass manager to catch
 859     // bugs caused by persistent state in the passes.
 860     std::unique_ptr<Module> M2(CloneModule(*M));
 861     // Run all passes on the original module first, so the second run processes
 862     // the clone to catch CloneModule bugs.
 863     Passes.run(*M);
 864     FirstRunBuffer = Buffer;
 865     Buffer.clear();
 866
 867     Passes.run(*M2);
 868
 869     // Compare the two outputs and make sure they're the same
 870     assert(Out);
 871     if (Buffer.size() != FirstRunBuffer.size() ||
 872         (memcmp(Buffer.data(), FirstRunBuffer.data(), Buffer.size()) != 0)) {
 873       errs()
 874           << "Running the pass manager twice changed the output.\n"
 875              "Writing the result of the second run to the specified output.\n"
 876              "To generate the one-run comparison binary, just run without\n"
 877              "the compile-twice option\n";
 878       if (ShouldEmitOutput) {
 879         Out->os() << BOS->str();
 880         Out->keep();
 881       }
 882       if (RemarksFile)
 883         RemarksFile->keep();
 884       return 1;
 885     }
 886     if (ShouldEmitOutput)
 887       Out->os() << BOS->str();
 888   }
 889
 890   if (DebugifyEach && !DebugifyExport.empty())
 891     exportDebugifyStats(DebugifyExport, Passes.getDebugifyStatsMap());
 892
 893   // Declare success.
 894   if (!NoOutput)
 895     Out->keep();
 896
 897   if (RemarksFile)
 898     RemarksFile->keep();
 899
 900   if (ThinLinkOut)
 901     ThinLinkOut->keep();
 902
 903   return 0;
 904 }