llvm/tools/llc/llc.cpp

   1 //===-- llc.cpp - Implement the LLVM Native Code Generator ----------------===//
   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 is the llc code generator driver. It provides a convenient
  10 // command-line interface for generating an assembly file or a relocatable file,
  11 // given LLVM bitcode.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "NewPMDriver.h"
  16 #include "llvm/ADT/STLExtras.h"
  17 #include "llvm/ADT/ScopeExit.h"
  18 #include "llvm/Analysis/TargetLibraryInfo.h"
  19 #include "llvm/CodeGen/CommandFlags.h"
  20 #include "llvm/CodeGen/LinkAllAsmWriterComponents.h"
  21 #include "llvm/CodeGen/LinkAllCodegenComponents.h"
  22 #include "llvm/CodeGen/MIRParser/MIRParser.h"
  23 #include "llvm/CodeGen/MachineFunctionPass.h"
  24 #include "llvm/CodeGen/MachineModuleInfo.h"
  25 #include "llvm/CodeGen/TargetPassConfig.h"
  26 #include "llvm/CodeGen/TargetSubtargetInfo.h"
  27 #include "llvm/IR/AutoUpgrade.h"
  28 #include "llvm/IR/DataLayout.h"
  29 #include "llvm/IR/DiagnosticInfo.h"
  30 #include "llvm/IR/DiagnosticPrinter.h"
  31 #include "llvm/IR/LLVMContext.h"
  32 #include "llvm/IR/LLVMRemarkStreamer.h"
  33 #include "llvm/IR/LegacyPassManager.h"
  34 #include "llvm/IR/Module.h"
  35 #include "llvm/IR/Verifier.h"
  36 #include "llvm/IRReader/IRReader.h"
  37 #include "llvm/InitializePasses.h"
  38 #include "llvm/MC/MCTargetOptionsCommandFlags.h"
  39 #include "llvm/MC/TargetRegistry.h"
  40 #include "llvm/Pass.h"
  41 #include "llvm/Remarks/HotnessThresholdParser.h"
  42 #include "llvm/Support/CommandLine.h"
  43 #include "llvm/Support/Debug.h"
  44 #include "llvm/Support/FileSystem.h"
  45 #include "llvm/Support/FormattedStream.h"
  46 #include "llvm/Support/InitLLVM.h"
  47 #include "llvm/Support/PluginLoader.h"
  48 #include "llvm/Support/SourceMgr.h"
  49 #include "llvm/Support/TargetSelect.h"
  50 #include "llvm/Support/TimeProfiler.h"
  51 #include "llvm/Support/ToolOutputFile.h"
  52 #include "llvm/Support/WithColor.h"
  53 #include "llvm/Target/TargetLoweringObjectFile.h"
  54 #include "llvm/Target/TargetMachine.h"
  55 #include "llvm/TargetParser/Host.h"
  56 #include "llvm/TargetParser/SubtargetFeature.h"
  57 #include "llvm/TargetParser/Triple.h"
  58 #include "llvm/Transforms/Utils/Cloning.h"
  59 #include <memory>
  60 #include <optional>
  61 using namespace llvm;
  62
  63 static codegen::RegisterCodeGenFlags CGF;
  64
  65 // General options for llc.  Other pass-specific options are specified
  66 // within the corresponding llc passes, and target-specific options
  67 // and back-end code generation options are specified with the target machine.
  68 //
  69 static cl::opt<std::string>
  70 InputFilename(cl::Positional, cl::desc("<input bitcode>"), cl::init("-"));
  71
  72 static cl::opt<std::string>
  73 InputLanguage("x", cl::desc("Input language ('ir' or 'mir')"));
  74
  75 static cl::opt<std::string>
  76 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
  77
  78 static cl::opt<std::string>
  79     SplitDwarfOutputFile("split-dwarf-output",
  80                          cl::desc(".dwo output filename"),
  81                          cl::value_desc("filename"));
  82
  83 static cl::opt<unsigned>
  84 TimeCompilations("time-compilations", cl::Hidden, cl::init(1u),
  85                  cl::value_desc("N"),
  86                  cl::desc("Repeat compilation N times for timing"));
  87
  88 static cl::opt<bool> TimeTrace("time-trace", cl::desc("Record time trace"));
  89
  90 static cl::opt<unsigned> TimeTraceGranularity(
  91     "time-trace-granularity",
  92     cl::desc(
  93         "Minimum time granularity (in microseconds) traced by time profiler"),
  94     cl::init(500), cl::Hidden);
  95
  96 static cl::opt<std::string>
  97     TimeTraceFile("time-trace-file",
  98                   cl::desc("Specify time trace file destination"),
  99                   cl::value_desc("filename"));
 100
 101 static cl::opt<std::string>
 102     BinutilsVersion("binutils-version", cl::Hidden,
 103                     cl::desc("Produced object files can use all ELF features "
 104                              "supported by this binutils version and newer."
 105                              "If -no-integrated-as is specified, the generated "
 106                              "assembly will consider GNU as support."
 107                              "'none' means that all ELF features can be used, "
 108                              "regardless of binutils support"));
 109
 110 static cl::opt<bool>
 111     PreserveComments("preserve-as-comments", cl::Hidden,
 112                      cl::desc("Preserve Comments in outputted assembly"),
 113                      cl::init(true));
 114
 115 // Determine optimization level.
 116 static cl::opt<char>
 117     OptLevel("O",
 118              cl::desc("Optimization level. [-O0, -O1, -O2, or -O3] "
 119                       "(default = '-O2')"),
 120              cl::Prefix, cl::init('2'));
 121
 122 static cl::opt<std::string>
 123 TargetTriple("mtriple", cl::desc("Override target triple for module"));
 124
 125 static cl::opt<std::string> SplitDwarfFile(
 126     "split-dwarf-file",
 127     cl::desc(
 128         "Specify the name of the .dwo file to encode in the DWARF output"));
 129
 130 static cl::opt<bool> NoVerify("disable-verify", cl::Hidden,
 131                               cl::desc("Do not verify input module"));
 132
 133 static cl::opt<bool> DisableSimplifyLibCalls("disable-simplify-libcalls",
 134                                              cl::desc("Disable simplify-libcalls"));
 135
 136 static cl::opt<bool> ShowMCEncoding("show-mc-encoding", cl::Hidden,
 137                                     cl::desc("Show encoding in .s output"));
 138
 139 static cl::opt<bool>
 140     DwarfDirectory("dwarf-directory", cl::Hidden,
 141                    cl::desc("Use .file directives with an explicit directory"),
 142                    cl::init(true));
 143
 144 static cl::opt<bool> AsmVerbose("asm-verbose",
 145                                 cl::desc("Add comments to directives."),
 146                                 cl::init(true));
 147
 148 static cl::opt<bool>
 149     CompileTwice("compile-twice", cl::Hidden,
 150                  cl::desc("Run everything twice, re-using the same pass "
 151                           "manager and verify the result is the same."),
 152                  cl::init(false));
 153
 154 static cl::opt<bool> DiscardValueNames(
 155     "discard-value-names",
 156     cl::desc("Discard names from Value (other than GlobalValue)."),
 157     cl::init(false), cl::Hidden);
 158
 159 static cl::list<std::string> IncludeDirs("I", cl::desc("include search path"));
 160
 161 static cl::opt<bool> RemarksWithHotness(
 162     "pass-remarks-with-hotness",
 163     cl::desc("With PGO, include profile count in optimization remarks"),
 164     cl::Hidden);
 165
 166 static cl::opt<std::optional<uint64_t>, false, remarks::HotnessThresholdParser>
 167     RemarksHotnessThreshold(
 168         "pass-remarks-hotness-threshold",
 169         cl::desc("Minimum profile count required for "
 170                  "an optimization remark to be output. "
 171                  "Use 'auto' to apply the threshold from profile summary."),
 172         cl::value_desc("N or 'auto'"), cl::init(0), cl::Hidden);
 173
 174 static cl::opt<std::string>
 175     RemarksFilename("pass-remarks-output",
 176                     cl::desc("Output filename for pass remarks"),
 177                     cl::value_desc("filename"));
 178
 179 static cl::opt<std::string>
 180     RemarksPasses("pass-remarks-filter",
 181                   cl::desc("Only record optimization remarks from passes whose "
 182                            "names match the given regular expression"),
 183                   cl::value_desc("regex"));
 184
 185 static cl::opt<std::string> RemarksFormat(
 186     "pass-remarks-format",
 187     cl::desc("The format used for serializing remarks (default: YAML)"),
 188     cl::value_desc("format"), cl::init("yaml"));
 189
 190 static cl::opt<bool> EnableNewPassManager(
 191     "enable-new-pm", cl::desc("Enable the new pass manager"), cl::init(false));
 192
 193 // This flag specifies a textual description of the optimization pass pipeline
 194 // to run over the module. This flag switches opt to use the new pass manager
 195 // infrastructure, completely disabling all of the flags specific to the old
 196 // pass management.
 197 static cl::opt<std::string> PassPipeline(
 198     "passes",
 199     cl::desc(
 200         "A textual description of the pass pipeline. To have analysis passes "
 201         "available before a certain pass, add 'require<foo-analysis>'."));
 202 static cl::alias PassPipeline2("p", cl::aliasopt(PassPipeline),
 203                                cl::desc("Alias for -passes"));
 204
 205 static cl::opt<bool> TryUseNewDbgInfoFormat(
 206     "try-experimental-debuginfo-iterators",
 207     cl::desc("Enable debuginfo iterator positions, if they're built in"),
 208     cl::init(false), cl::Hidden);
 209
 210 extern cl::opt<bool> UseNewDbgInfoFormat;
 211
 212 namespace {
 213
 214 std::vector<std::string> &getRunPassNames() {
 215   static std::vector<std::string> RunPassNames;
 216   return RunPassNames;
 217 }
 218
 219 struct RunPassOption {
 220   void operator=(const std::string &Val) const {
 221     if (Val.empty())
 222       return;
 223     SmallVector<StringRef, 8> PassNames;
 224     StringRef(Val).split(PassNames, ',', -1, false);
 225     for (auto PassName : PassNames)
 226       getRunPassNames().push_back(std::string(PassName));
 227   }
 228 };
 229 } // namespace
 230
 231 static RunPassOption RunPassOpt;
 232
 233 static cl::opt<RunPassOption, true, cl::parser<std::string>> RunPass(
 234     "run-pass",
 235     cl::desc("Run compiler only for specified passes (comma separated list)"),
 236     cl::value_desc("pass-name"), cl::location(RunPassOpt));
 237
 238 static int compileModule(char **, LLVMContext &);
 239
 240 [[noreturn]] static void reportError(Twine Msg, StringRef Filename = "") {
 241   SmallString<256> Prefix;
 242   if (!Filename.empty()) {
 243     if (Filename == "-")
 244       Filename = "<stdin>";
 245     ("'" + Twine(Filename) + "': ").toStringRef(Prefix);
 246   }
 247   WithColor::error(errs(), "llc") << Prefix << Msg << "\n";
 248   exit(1);
 249 }
 250
 251 [[noreturn]] static void reportError(Error Err, StringRef Filename) {
 252   assert(Err);
 253   handleAllErrors(createFileError(Filename, std::move(Err)),
 254                   [&](const ErrorInfoBase &EI) { reportError(EI.message()); });
 255   llvm_unreachable("reportError() should not return");
 256 }
 257
 258 static std::unique_ptr<ToolOutputFile> GetOutputStream(const char *TargetName,
 259                                                        Triple::OSType OS,
 260                                                        const char *ProgName) {
 261   // If we don't yet have an output filename, make one.
 262   if (OutputFilename.empty()) {
 263     if (InputFilename == "-")
 264       OutputFilename = "-";
 265     else {
 266       // If InputFilename ends in .bc or .ll, remove it.
 267       StringRef IFN = InputFilename;
 268       if (IFN.ends_with(".bc") || IFN.ends_with(".ll"))
 269         OutputFilename = std::string(IFN.drop_back(3));
 270       else if (IFN.ends_with(".mir"))
 271         OutputFilename = std::string(IFN.drop_back(4));
 272       else
 273         OutputFilename = std::string(IFN);
 274
 275       switch (codegen::getFileType()) {
 276       case CodeGenFileType::AssemblyFile:
 277         OutputFilename += ".s";
 278         break;
 279       case CodeGenFileType::ObjectFile:
 280         if (OS == Triple::Win32)
 281           OutputFilename += ".obj";
 282         else
 283           OutputFilename += ".o";
 284         break;
 285       case CodeGenFileType::Null:
 286         OutputFilename = "-";
 287         break;
 288       }
 289     }
 290   }
 291
 292   // Decide if we need "binary" output.
 293   bool Binary = false;
 294   switch (codegen::getFileType()) {
 295   case CodeGenFileType::AssemblyFile:
 296     break;
 297   case CodeGenFileType::ObjectFile:
 298   case CodeGenFileType::Null:
 299     Binary = true;
 300     break;
 301   }
 302
 303   // Open the file.
 304   std::error_code EC;
 305   sys::fs::OpenFlags OpenFlags = sys::fs::OF_None;
 306   if (!Binary)
 307     OpenFlags |= sys::fs::OF_TextWithCRLF;
 308   auto FDOut = std::make_unique<ToolOutputFile>(OutputFilename, EC, OpenFlags);
 309   if (EC) {
 310     reportError(EC.message());
 311     return nullptr;
 312   }
 313
 314   return FDOut;
 315 }
 316
 317 // main - Entry point for the llc compiler.
 318 //
 319 int main(int argc, char **argv) {
 320   InitLLVM X(argc, argv);
 321
 322   // Enable debug stream buffering.
 323   EnableDebugBuffering = true;
 324
 325   // Initialize targets first, so that --version shows registered targets.
 326   InitializeAllTargets();
 327   InitializeAllTargetMCs();
 328   InitializeAllAsmPrinters();
 329   InitializeAllAsmParsers();
 330
 331   // Initialize codegen and IR passes used by llc so that the -print-after,
 332   // -print-before, and -stop-after options work.
 333   PassRegistry *Registry = PassRegistry::getPassRegistry();
 334   initializeCore(*Registry);
 335   initializeCodeGen(*Registry);
 336   initializeLoopStrengthReducePass(*Registry);
 337   initializeLowerIntrinsicsPass(*Registry);
 338   initializeUnreachableBlockElimLegacyPassPass(*Registry);
 339   initializeConstantHoistingLegacyPassPass(*Registry);
 340   initializeScalarOpts(*Registry);
 341   initializeVectorization(*Registry);
 342   initializeScalarizeMaskedMemIntrinLegacyPassPass(*Registry);
 343   initializeExpandReductionsPass(*Registry);
 344   initializeExpandVectorPredicationPass(*Registry);
 345   initializeHardwareLoopsLegacyPass(*Registry);
 346   initializeTransformUtils(*Registry);
 347   initializeReplaceWithVeclibLegacyPass(*Registry);
 348   initializeTLSVariableHoistLegacyPassPass(*Registry);
 349
 350   // Initialize debugging passes.
 351   initializeScavengerTestPass(*Registry);
 352
 353   // Register the Target and CPU printer for --version.
 354   cl::AddExtraVersionPrinter(sys::printDefaultTargetAndDetectedCPU);
 355   // Register the target printer for --version.
 356   cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
 357
 358   cl::ParseCommandLineOptions(argc, argv, "llvm system compiler\n");
 359
 360   if (!PassPipeline.empty() && !getRunPassNames().empty()) {
 361     errs() << "The `llc -run-pass=...` syntax for the new pass manager is "
 362               "not supported, please use `llc -passes=<pipeline>` (or the `-p` "
 363               "alias for a more concise version).\n";
 364     return 1;
 365   }
 366
 367   // RemoveDIs debug-info transition: tests may request that we /try/ to use the
 368   // new debug-info format, if it's built in.
 369 #ifdef EXPERIMENTAL_DEBUGINFO_ITERATORS
 370   if (TryUseNewDbgInfoFormat) {
 371     // If LLVM was built with support for this, turn the new debug-info format
 372     // on.
 373     UseNewDbgInfoFormat = true;
 374   }
 375 #endif
 376   (void)TryUseNewDbgInfoFormat;
 377
 378   if (TimeTrace)
 379     timeTraceProfilerInitialize(TimeTraceGranularity, argv[0]);
 380   auto TimeTraceScopeExit = make_scope_exit([]() {
 381     if (TimeTrace) {
 382       if (auto E = timeTraceProfilerWrite(TimeTraceFile, OutputFilename)) {
 383         handleAllErrors(std::move(E), [&](const StringError &SE) {
 384           errs() << SE.getMessage() << "\n";
 385         });
 386         return;
 387       }
 388       timeTraceProfilerCleanup();
 389     }
 390   });
 391
 392   LLVMContext Context;
 393   Context.setDiscardValueNames(DiscardValueNames);
 394
 395   // Set a diagnostic handler that doesn't exit on the first error
 396   Context.setDiagnosticHandler(std::make_unique<LLCDiagnosticHandler>());
 397
 398   Expected<std::unique_ptr<ToolOutputFile>> RemarksFileOrErr =
 399       setupLLVMOptimizationRemarks(Context, RemarksFilename, RemarksPasses,
 400                                    RemarksFormat, RemarksWithHotness,
 401                                    RemarksHotnessThreshold);
 402   if (Error E = RemarksFileOrErr.takeError())
 403     reportError(std::move(E), RemarksFilename);
 404   std::unique_ptr<ToolOutputFile> RemarksFile = std::move(*RemarksFileOrErr);
 405
 406   if (InputLanguage != "" && InputLanguage != "ir" && InputLanguage != "mir")
 407     reportError("input language must be '', 'IR' or 'MIR'");
 408
 409   // Compile the module TimeCompilations times to give better compile time
 410   // metrics.
 411   for (unsigned I = TimeCompilations; I; --I)
 412     if (int RetVal = compileModule(argv, Context))
 413       return RetVal;
 414
 415   if (RemarksFile)
 416     RemarksFile->keep();
 417   return 0;
 418 }
 419
 420 static bool addPass(PassManagerBase &PM, const char *argv0,
 421                     StringRef PassName, TargetPassConfig &TPC) {
 422   if (PassName == "none")
 423     return false;
 424
 425   const PassRegistry *PR = PassRegistry::getPassRegistry();
 426   const PassInfo *PI = PR->getPassInfo(PassName);
 427   if (!PI) {
 428     WithColor::error(errs(), argv0)
 429         << "run-pass " << PassName << " is not registered.\n";
 430     return true;
 431   }
 432
 433   Pass *P;
 434   if (PI->getNormalCtor())
 435     P = PI->getNormalCtor()();
 436   else {
 437     WithColor::error(errs(), argv0)
 438         << "cannot create pass: " << PI->getPassName() << "\n";
 439     return true;
 440   }
 441   std::string Banner = std::string("After ") + std::string(P->getPassName());
 442   TPC.addMachinePrePasses();
 443   PM.add(P);
 444   TPC.addMachinePostPasses(Banner);
 445
 446   return false;
 447 }
 448
 449 static int compileModule(char **argv, LLVMContext &Context) {
 450   // Load the module to be compiled...
 451   SMDiagnostic Err;
 452   std::unique_ptr<Module> M;
 453   std::unique_ptr<MIRParser> MIR;
 454   Triple TheTriple;
 455   std::string CPUStr = codegen::getCPUStr(),
 456               FeaturesStr = codegen::getFeaturesStr();
 457
 458   // Set attributes on functions as loaded from MIR from command line arguments.
 459   auto setMIRFunctionAttributes = [&CPUStr, &FeaturesStr](Function &F) {
 460     codegen::setFunctionAttributes(CPUStr, FeaturesStr, F);
 461   };
 462
 463   auto MAttrs = codegen::getMAttrs();
 464   bool SkipModule =
 465       CPUStr == "help" || (!MAttrs.empty() && MAttrs.front() == "help");
 466
 467   CodeGenOptLevel OLvl;
 468   if (auto Level = CodeGenOpt::parseLevel(OptLevel)) {
 469     OLvl = *Level;
 470   } else {
 471     WithColor::error(errs(), argv[0]) << "invalid optimization level.\n";
 472     return 1;
 473   }
 474
 475   // Parse 'none' or '$major.$minor'. Disallow -binutils-version=0 because we
 476   // use that to indicate the MC default.
 477   if (!BinutilsVersion.empty() && BinutilsVersion != "none") {
 478     StringRef V = BinutilsVersion.getValue();
 479     unsigned Num;
 480     if (V.consumeInteger(10, Num) || Num == 0 ||
 481         !(V.empty() ||
 482           (V.consume_front(".") && !V.consumeInteger(10, Num) && V.empty()))) {
 483       WithColor::error(errs(), argv[0])
 484           << "invalid -binutils-version, accepting 'none' or major.minor\n";
 485       return 1;
 486     }
 487   }
 488   TargetOptions Options;
 489   auto InitializeOptions = [&](const Triple &TheTriple) {
 490     Options = codegen::InitTargetOptionsFromCodeGenFlags(TheTriple);
 491
 492     if (Options.XCOFFReadOnlyPointers) {
 493       if (!TheTriple.isOSAIX())
 494         reportError("-mxcoff-roptr option is only supported on AIX",
 495                     InputFilename);
 496
 497       // Since the storage mapping class is specified per csect,
 498       // without using data sections, it is less effective to use read-only
 499       // pointers. Using read-only pointers may cause other RO variables in the
 500       // same csect to become RW when the linker acts upon `-bforceimprw`;
 501       // therefore, we require that separate data sections are used in the
 502       // presence of ReadOnlyPointers. We respect the setting of data-sections
 503       // since we have not found reasons to do otherwise that overcome the user
 504       // surprise of not respecting the setting.
 505       if (!Options.DataSections)
 506         reportError("-mxcoff-roptr option must be used with -data-sections",
 507                     InputFilename);
 508     }
 509
 510     Options.BinutilsVersion =
 511         TargetMachine::parseBinutilsVersion(BinutilsVersion);
 512     Options.MCOptions.ShowMCEncoding = ShowMCEncoding;
 513     Options.MCOptions.AsmVerbose = AsmVerbose;
 514     Options.MCOptions.PreserveAsmComments = PreserveComments;
 515     Options.MCOptions.IASSearchPaths = IncludeDirs;
 516     Options.MCOptions.SplitDwarfFile = SplitDwarfFile;
 517     if (DwarfDirectory.getPosition()) {
 518       Options.MCOptions.MCUseDwarfDirectory =
 519           DwarfDirectory ? MCTargetOptions::EnableDwarfDirectory
 520                          : MCTargetOptions::DisableDwarfDirectory;
 521     } else {
 522       // -dwarf-directory is not set explicitly. Some assemblers
 523       // (e.g. GNU as or ptxas) do not support `.file directory'
 524       // syntax prior to DWARFv5. Let the target decide the default
 525       // value.
 526       Options.MCOptions.MCUseDwarfDirectory =
 527           MCTargetOptions::DefaultDwarfDirectory;
 528     }
 529   };
 530
 531   std::optional<Reloc::Model> RM = codegen::getExplicitRelocModel();
 532   std::optional<CodeModel::Model> CM = codegen::getExplicitCodeModel();
 533
 534   const Target *TheTarget = nullptr;
 535   std::unique_ptr<TargetMachine> Target;
 536
 537   // If user just wants to list available options, skip module loading
 538   if (!SkipModule) {
 539     auto SetDataLayout = [&](StringRef DataLayoutTargetTriple,
 540                              StringRef OldDLStr) -> std::optional<std::string> {
 541       // If we are supposed to override the target triple, do so now.
 542       std::string IRTargetTriple = DataLayoutTargetTriple.str();
 543       if (!TargetTriple.empty())
 544         IRTargetTriple = Triple::normalize(TargetTriple);
 545       TheTriple = Triple(IRTargetTriple);
 546       if (TheTriple.getTriple().empty())
 547         TheTriple.setTriple(sys::getDefaultTargetTriple());
 548
 549       std::string Error;
 550       TheTarget =
 551           TargetRegistry::lookupTarget(codegen::getMArch(), TheTriple, Error);
 552       if (!TheTarget) {
 553         WithColor::error(errs(), argv[0]) << Error;
 554         exit(1);
 555       }
 556
 557       InitializeOptions(TheTriple);
 558       Target = std::unique_ptr<TargetMachine>(TheTarget->createTargetMachine(
 559           TheTriple.getTriple(), CPUStr, FeaturesStr, Options, RM, CM, OLvl));
 560       assert(Target && "Could not allocate target machine!");
 561
 562       return Target->createDataLayout().getStringRepresentation();
 563     };
 564     if (InputLanguage == "mir" ||
 565         (InputLanguage == "" && StringRef(InputFilename).ends_with(".mir"))) {
 566       MIR = createMIRParserFromFile(InputFilename, Err, Context,
 567                                     setMIRFunctionAttributes);
 568       if (MIR)
 569         M = MIR->parseIRModule(SetDataLayout);
 570     } else {
 571       M = parseIRFile(InputFilename, Err, Context,
 572                       ParserCallbacks(SetDataLayout));
 573     }
 574     if (!M) {
 575       Err.print(argv[0], WithColor::error(errs(), argv[0]));
 576       return 1;
 577     }
 578     if (!TargetTriple.empty())
 579       M->setTargetTriple(Triple::normalize(TargetTriple));
 580
 581     std::optional<CodeModel::Model> CM_IR = M->getCodeModel();
 582     if (!CM && CM_IR)
 583       Target->setCodeModel(*CM_IR);
 584     if (std::optional<uint64_t> LDT = codegen::getExplicitLargeDataThreshold())
 585       Target->setLargeDataThreshold(*LDT);
 586   } else {
 587     TheTriple = Triple(Triple::normalize(TargetTriple));
 588     if (TheTriple.getTriple().empty())
 589       TheTriple.setTriple(sys::getDefaultTargetTriple());
 590
 591     // Get the target specific parser.
 592     std::string Error;
 593     TheTarget =
 594         TargetRegistry::lookupTarget(codegen::getMArch(), TheTriple, Error);
 595     if (!TheTarget) {
 596       WithColor::error(errs(), argv[0]) << Error;
 597       return 1;
 598     }
 599
 600     InitializeOptions(TheTriple);
 601     Target = std::unique_ptr<TargetMachine>(TheTarget->createTargetMachine(
 602         TheTriple.getTriple(), CPUStr, FeaturesStr, Options, RM, CM, OLvl));
 603     assert(Target && "Could not allocate target machine!");
 604
 605     // If we don't have a module then just exit now. We do this down
 606     // here since the CPU/Feature help is underneath the target machine
 607     // creation.
 608     return 0;
 609   }
 610
 611   assert(M && "Should have exited if we didn't have a module!");
 612   if (codegen::getFloatABIForCalls() != FloatABI::Default)
 613     Target->Options.FloatABIType = codegen::getFloatABIForCalls();
 614
 615   // Figure out where we are going to send the output.
 616   std::unique_ptr<ToolOutputFile> Out =
 617       GetOutputStream(TheTarget->getName(), TheTriple.getOS(), argv[0]);
 618   if (!Out) return 1;
 619
 620   // Ensure the filename is passed down to CodeViewDebug.
 621   Target->Options.ObjectFilenameForDebug = Out->outputFilename();
 622
 623   std::unique_ptr<ToolOutputFile> DwoOut;
 624   if (!SplitDwarfOutputFile.empty()) {
 625     std::error_code EC;
 626     DwoOut = std::make_unique<ToolOutputFile>(SplitDwarfOutputFile, EC,
 627                                                sys::fs::OF_None);
 628     if (EC)
 629       reportError(EC.message(), SplitDwarfOutputFile);
 630   }
 631
 632   // Add an appropriate TargetLibraryInfo pass for the module's triple.
 633   TargetLibraryInfoImpl TLII(Triple(M->getTargetTriple()));
 634
 635   // The -disable-simplify-libcalls flag actually disables all builtin optzns.
 636   if (DisableSimplifyLibCalls)
 637     TLII.disableAllFunctions();
 638
 639   // Verify module immediately to catch problems before doInitialization() is
 640   // called on any passes.
 641   if (!NoVerify && verifyModule(*M, &errs()))
 642     reportError("input module cannot be verified", InputFilename);
 643
 644   // Override function attributes based on CPUStr, FeaturesStr, and command line
 645   // flags.
 646   codegen::setFunctionAttributes(CPUStr, FeaturesStr, *M);
 647
 648   if (mc::getExplicitRelaxAll() &&
 649       codegen::getFileType() != CodeGenFileType::ObjectFile)
 650     WithColor::warning(errs(), argv[0])
 651         << ": warning: ignoring -mc-relax-all because filetype != obj";
 652
 653   if (EnableNewPassManager || !PassPipeline.empty()) {
 654     return compileModuleWithNewPM(argv[0], std::move(M), std::move(MIR),
 655                                   std::move(Target), std::move(Out),
 656                                   std::move(DwoOut), Context, TLII, NoVerify,
 657                                   PassPipeline, codegen::getFileType());
 658   }
 659
 660   // Build up all of the passes that we want to do to the module.
 661   legacy::PassManager PM;
 662   PM.add(new TargetLibraryInfoWrapperPass(TLII));
 663
 664   {
 665     raw_pwrite_stream *OS = &Out->os();
 666
 667     // Manually do the buffering rather than using buffer_ostream,
 668     // so we can memcmp the contents in CompileTwice mode
 669     SmallVector<char, 0> Buffer;
 670     std::unique_ptr<raw_svector_ostream> BOS;
 671     if ((codegen::getFileType() != CodeGenFileType::AssemblyFile &&
 672          !Out->os().supportsSeeking()) ||
 673         CompileTwice) {
 674       BOS = std::make_unique<raw_svector_ostream>(Buffer);
 675       OS = BOS.get();
 676     }
 677
 678     const char *argv0 = argv[0];
 679     LLVMTargetMachine &LLVMTM = static_cast<LLVMTargetMachine &>(*Target);
 680     MachineModuleInfoWrapperPass *MMIWP =
 681         new MachineModuleInfoWrapperPass(&LLVMTM);
 682
 683     // Construct a custom pass pipeline that starts after instruction
 684     // selection.
 685     if (!getRunPassNames().empty()) {
 686       if (!MIR) {
 687         WithColor::warning(errs(), argv[0])
 688             << "run-pass is for .mir file only.\n";
 689         delete MMIWP;
 690         return 1;
 691       }
 692       TargetPassConfig *PTPC = LLVMTM.createPassConfig(PM);
 693       TargetPassConfig &TPC = *PTPC;
 694       if (TPC.hasLimitedCodeGenPipeline()) {
 695         WithColor::warning(errs(), argv[0])
 696             << "run-pass cannot be used with "
 697             << TPC.getLimitedCodeGenPipelineReason() << ".\n";
 698         delete PTPC;
 699         delete MMIWP;
 700         return 1;
 701       }
 702
 703       TPC.setDisableVerify(NoVerify);
 704       PM.add(&TPC);
 705       PM.add(MMIWP);
 706       TPC.printAndVerify("");
 707       for (const std::string &RunPassName : getRunPassNames()) {
 708         if (addPass(PM, argv0, RunPassName, TPC))
 709           return 1;
 710       }
 711       TPC.setInitialized();
 712       PM.add(createPrintMIRPass(*OS));
 713       PM.add(createFreeMachineFunctionPass());
 714     } else if (Target->addPassesToEmitFile(
 715                    PM, *OS, DwoOut ? &DwoOut->os() : nullptr,
 716                    codegen::getFileType(), NoVerify, MMIWP)) {
 717       reportError("target does not support generation of this file type");
 718     }
 719
 720     const_cast<TargetLoweringObjectFile *>(LLVMTM.getObjFileLowering())
 721         ->Initialize(MMIWP->getMMI().getContext(), *Target);
 722     if (MIR) {
 723       assert(MMIWP && "Forgot to create MMIWP?");
 724       if (MIR->parseMachineFunctions(*M, MMIWP->getMMI()))
 725         return 1;
 726     }
 727
 728     // Before executing passes, print the final values of the LLVM options.
 729     cl::PrintOptionValues();
 730
 731     // If requested, run the pass manager over the same module again,
 732     // to catch any bugs due to persistent state in the passes. Note that
 733     // opt has the same functionality, so it may be worth abstracting this out
 734     // in the future.
 735     SmallVector<char, 0> CompileTwiceBuffer;
 736     if (CompileTwice) {
 737       std::unique_ptr<Module> M2(llvm::CloneModule(*M));
 738       PM.run(*M2);
 739       CompileTwiceBuffer = Buffer;
 740       Buffer.clear();
 741     }
 742
 743     PM.run(*M);
 744
 745     if (Context.getDiagHandlerPtr()->HasErrors)
 746       return 1;
 747
 748     // Compare the two outputs and make sure they're the same
 749     if (CompileTwice) {
 750       if (Buffer.size() != CompileTwiceBuffer.size() ||
 751           (memcmp(Buffer.data(), CompileTwiceBuffer.data(), Buffer.size()) !=
 752            0)) {
 753         errs()
 754             << "Running the pass manager twice changed the output.\n"
 755                "Writing the result of the second run to the specified output\n"
 756                "To generate the one-run comparison binary, just run without\n"
 757                "the compile-twice option\n";
 758         Out->os() << Buffer;
 759         Out->keep();
 760         return 1;
 761       }
 762     }
 763
 764     if (BOS) {
 765       Out->os() << Buffer;
 766     }
 767   }
 768
 769   // Declare success.
 770   Out->keep();
 771   if (DwoOut)
 772     DwoOut->keep();
 773
 774   return 0;
 775 }