clang/tools/driver/cc1as_main.cpp

   1 //===-- cc1as_main.cpp - Clang Assembler  ---------------------------------===//
   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 entry point to the clang -cc1as functionality, which implements
  10 // the direct interface to the LLVM MC based assembler.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "clang/Basic/Diagnostic.h"
  15 #include "clang/Basic/DiagnosticOptions.h"
  16 #include "clang/Driver/DriverDiagnostic.h"
  17 #include "clang/Driver/Options.h"
  18 #include "clang/Frontend/FrontendDiagnostic.h"
  19 #include "clang/Frontend/TextDiagnosticPrinter.h"
  20 #include "clang/Frontend/Utils.h"
  21 #include "llvm/ADT/STLExtras.h"
  22 #include "llvm/ADT/StringExtras.h"
  23 #include "llvm/ADT/StringSwitch.h"
  24 #include "llvm/IR/DataLayout.h"
  25 #include "llvm/MC/MCAsmBackend.h"
  26 #include "llvm/MC/MCAsmInfo.h"
  27 #include "llvm/MC/MCCodeEmitter.h"
  28 #include "llvm/MC/MCContext.h"
  29 #include "llvm/MC/MCInstrInfo.h"
  30 #include "llvm/MC/MCObjectFileInfo.h"
  31 #include "llvm/MC/MCObjectWriter.h"
  32 #include "llvm/MC/MCParser/MCAsmParser.h"
  33 #include "llvm/MC/MCParser/MCTargetAsmParser.h"
  34 #include "llvm/MC/MCRegisterInfo.h"
  35 #include "llvm/MC/MCSectionMachO.h"
  36 #include "llvm/MC/MCStreamer.h"
  37 #include "llvm/MC/MCSubtargetInfo.h"
  38 #include "llvm/MC/MCTargetOptions.h"
  39 #include "llvm/MC/TargetRegistry.h"
  40 #include "llvm/Option/Arg.h"
  41 #include "llvm/Option/ArgList.h"
  42 #include "llvm/Option/OptTable.h"
  43 #include "llvm/Support/CommandLine.h"
  44 #include "llvm/Support/ErrorHandling.h"
  45 #include "llvm/Support/FileSystem.h"
  46 #include "llvm/Support/FormattedStream.h"
  47 #include "llvm/Support/MemoryBuffer.h"
  48 #include "llvm/Support/Path.h"
  49 #include "llvm/Support/Process.h"
  50 #include "llvm/Support/Signals.h"
  51 #include "llvm/Support/SourceMgr.h"
  52 #include "llvm/Support/TargetSelect.h"
  53 #include "llvm/Support/Timer.h"
  54 #include "llvm/Support/raw_ostream.h"
  55 #include "llvm/TargetParser/Host.h"
  56 #include "llvm/TargetParser/Triple.h"
  57 #include <memory>
  58 #include <optional>
  59 #include <system_error>
  60 using namespace clang;
  61 using namespace clang::driver;
  62 using namespace clang::driver::options;
  63 using namespace llvm;
  64 using namespace llvm::opt;
  65
  66 namespace {
  67
  68 /// Helper class for representing a single invocation of the assembler.
  69 struct AssemblerInvocation {
  70   /// @name Target Options
  71   /// @{
  72
  73   /// The name of the target triple to assemble for.
  74   std::string Triple;
  75
  76   /// If given, the name of the target CPU to determine which instructions
  77   /// are legal.
  78   std::string CPU;
  79
  80   /// The list of target specific features to enable or disable -- this should
  81   /// be a list of strings starting with '+' or '-'.
  82   std::vector<std::string> Features;
  83
  84   /// The list of symbol definitions.
  85   std::vector<std::string> SymbolDefs;
  86
  87   /// @}
  88   /// @name Language Options
  89   /// @{
  90
  91   std::vector<std::string> IncludePaths;
  92   unsigned NoInitialTextSection : 1;
  93   unsigned SaveTemporaryLabels : 1;
  94   unsigned GenDwarfForAssembly : 1;
  95   unsigned RelaxELFRelocations : 1;
  96   unsigned Dwarf64 : 1;
  97   unsigned DwarfVersion;
  98   std::string DwarfDebugFlags;
  99   std::string DwarfDebugProducer;
 100   std::string DebugCompilationDir;
 101   llvm::SmallVector<std::pair<std::string, std::string>, 0> DebugPrefixMap;
 102   llvm::DebugCompressionType CompressDebugSections =
 103       llvm::DebugCompressionType::None;
 104   std::string MainFileName;
 105   std::string SplitDwarfOutput;
 106
 107   /// @}
 108   /// @name Frontend Options
 109   /// @{
 110
 111   std::string InputFile;
 112   std::vector<std::string> LLVMArgs;
 113   std::string OutputPath;
 114   enum FileType {
 115     FT_Asm,  ///< Assembly (.s) output, transliterate mode.
 116     FT_Null, ///< No output, for timing purposes.
 117     FT_Obj   ///< Object file output.
 118   };
 119   FileType OutputType;
 120   unsigned ShowHelp : 1;
 121   unsigned ShowVersion : 1;
 122
 123   /// @}
 124   /// @name Transliterate Options
 125   /// @{
 126
 127   unsigned OutputAsmVariant;
 128   unsigned ShowEncoding : 1;
 129   unsigned ShowInst : 1;
 130
 131   /// @}
 132   /// @name Assembler Options
 133   /// @{
 134
 135   unsigned RelaxAll : 1;
 136   unsigned NoExecStack : 1;
 137   unsigned FatalWarnings : 1;
 138   unsigned NoWarn : 1;
 139   unsigned NoTypeCheck : 1;
 140   unsigned IncrementalLinkerCompatible : 1;
 141   unsigned EmbedBitcode : 1;
 142
 143   /// Whether to emit DWARF unwind info.
 144   EmitDwarfUnwindType EmitDwarfUnwind;
 145
 146   // Whether to emit compact-unwind for non-canonical entries.
 147   // Note: maybe overriden by other constraints.
 148   unsigned EmitCompactUnwindNonCanonical : 1;
 149
 150   /// The name of the relocation model to use.
 151   std::string RelocationModel;
 152
 153   /// The ABI targeted by the backend. Specified using -target-abi. Empty
 154   /// otherwise.
 155   std::string TargetABI;
 156
 157   /// Darwin target variant triple, the variant of the deployment target
 158   /// for which the code is being compiled.
 159   std::optional<llvm::Triple> DarwinTargetVariantTriple;
 160
 161   /// The version of the darwin target variant SDK which was used during the
 162   /// compilation
 163   llvm::VersionTuple DarwinTargetVariantSDKVersion;
 164
 165   /// The name of a file to use with \c .secure_log_unique directives.
 166   std::string AsSecureLogFile;
 167   /// @}
 168
 169 public:
 170   AssemblerInvocation() {
 171     Triple = "";
 172     NoInitialTextSection = 0;
 173     InputFile = "-";
 174     OutputPath = "-";
 175     OutputType = FT_Asm;
 176     OutputAsmVariant = 0;
 177     ShowInst = 0;
 178     ShowEncoding = 0;
 179     RelaxAll = 0;
 180     NoExecStack = 0;
 181     FatalWarnings = 0;
 182     NoWarn = 0;
 183     NoTypeCheck = 0;
 184     IncrementalLinkerCompatible = 0;
 185     Dwarf64 = 0;
 186     DwarfVersion = 0;
 187     EmbedBitcode = 0;
 188     EmitDwarfUnwind = EmitDwarfUnwindType::Default;
 189     EmitCompactUnwindNonCanonical = false;
 190   }
 191
 192   static bool CreateFromArgs(AssemblerInvocation &Res,
 193                              ArrayRef<const char *> Argv,
 194                              DiagnosticsEngine &Diags);
 195 };
 196
 197 }
 198
 199 bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
 200                                          ArrayRef<const char *> Argv,
 201                                          DiagnosticsEngine &Diags) {
 202   bool Success = true;
 203
 204   // Parse the arguments.
 205   const OptTable &OptTbl = getDriverOptTable();
 206
 207   llvm::opt::Visibility VisibilityMask(options::CC1AsOption);
 208   unsigned MissingArgIndex, MissingArgCount;
 209   InputArgList Args =
 210       OptTbl.ParseArgs(Argv, MissingArgIndex, MissingArgCount, VisibilityMask);
 211
 212   // Check for missing argument error.
 213   if (MissingArgCount) {
 214     Diags.Report(diag::err_drv_missing_argument)
 215         << Args.getArgString(MissingArgIndex) << MissingArgCount;
 216     Success = false;
 217   }
 218
 219   // Issue errors on unknown arguments.
 220   for (const Arg *A : Args.filtered(OPT_UNKNOWN)) {
 221     auto ArgString = A->getAsString(Args);
 222     std::string Nearest;
 223     if (OptTbl.findNearest(ArgString, Nearest, VisibilityMask) > 1)
 224       Diags.Report(diag::err_drv_unknown_argument) << ArgString;
 225     else
 226       Diags.Report(diag::err_drv_unknown_argument_with_suggestion)
 227           << ArgString << Nearest;
 228     Success = false;
 229   }
 230
 231   // Construct the invocation.
 232
 233   // Target Options
 234   Opts.Triple = llvm::Triple::normalize(Args.getLastArgValue(OPT_triple));
 235   if (Arg *A = Args.getLastArg(options::OPT_darwin_target_variant_triple))
 236     Opts.DarwinTargetVariantTriple = llvm::Triple(A->getValue());
 237   if (Arg *A = Args.getLastArg(OPT_darwin_target_variant_sdk_version_EQ)) {
 238     VersionTuple Version;
 239     if (Version.tryParse(A->getValue()))
 240       Diags.Report(diag::err_drv_invalid_value)
 241           << A->getAsString(Args) << A->getValue();
 242     else
 243       Opts.DarwinTargetVariantSDKVersion = Version;
 244   }
 245
 246   Opts.CPU = std::string(Args.getLastArgValue(OPT_target_cpu));
 247   Opts.Features = Args.getAllArgValues(OPT_target_feature);
 248
 249   // Use the default target triple if unspecified.
 250   if (Opts.Triple.empty())
 251     Opts.Triple = llvm::sys::getDefaultTargetTriple();
 252
 253   // Language Options
 254   Opts.IncludePaths = Args.getAllArgValues(OPT_I);
 255   Opts.NoInitialTextSection = Args.hasArg(OPT_n);
 256   Opts.SaveTemporaryLabels = Args.hasArg(OPT_msave_temp_labels);
 257   // Any DebugInfoKind implies GenDwarfForAssembly.
 258   Opts.GenDwarfForAssembly = Args.hasArg(OPT_debug_info_kind_EQ);
 259
 260   if (const Arg *A = Args.getLastArg(OPT_compress_debug_sections_EQ)) {
 261     Opts.CompressDebugSections =
 262         llvm::StringSwitch<llvm::DebugCompressionType>(A->getValue())
 263             .Case("none", llvm::DebugCompressionType::None)
 264             .Case("zlib", llvm::DebugCompressionType::Zlib)
 265             .Case("zstd", llvm::DebugCompressionType::Zstd)
 266             .Default(llvm::DebugCompressionType::None);
 267   }
 268
 269   Opts.RelaxELFRelocations = !Args.hasArg(OPT_mrelax_relocations_no);
 270   if (auto *DwarfFormatArg = Args.getLastArg(OPT_gdwarf64, OPT_gdwarf32))
 271     Opts.Dwarf64 = DwarfFormatArg->getOption().matches(OPT_gdwarf64);
 272   Opts.DwarfVersion = getLastArgIntValue(Args, OPT_dwarf_version_EQ, 2, Diags);
 273   Opts.DwarfDebugFlags =
 274       std::string(Args.getLastArgValue(OPT_dwarf_debug_flags));
 275   Opts.DwarfDebugProducer =
 276       std::string(Args.getLastArgValue(OPT_dwarf_debug_producer));
 277   if (const Arg *A = Args.getLastArg(options::OPT_ffile_compilation_dir_EQ,
 278                                      options::OPT_fdebug_compilation_dir_EQ))
 279     Opts.DebugCompilationDir = A->getValue();
 280   Opts.MainFileName = std::string(Args.getLastArgValue(OPT_main_file_name));
 281
 282   for (const auto &Arg : Args.getAllArgValues(OPT_fdebug_prefix_map_EQ)) {
 283     auto Split = StringRef(Arg).split('=');
 284     Opts.DebugPrefixMap.emplace_back(Split.first, Split.second);
 285   }
 286
 287   // Frontend Options
 288   if (Args.hasArg(OPT_INPUT)) {
 289     bool First = true;
 290     for (const Arg *A : Args.filtered(OPT_INPUT)) {
 291       if (First) {
 292         Opts.InputFile = A->getValue();
 293         First = false;
 294       } else {
 295         Diags.Report(diag::err_drv_unknown_argument) << A->getAsString(Args);
 296         Success = false;
 297       }
 298     }
 299   }
 300   Opts.LLVMArgs = Args.getAllArgValues(OPT_mllvm);
 301   Opts.OutputPath = std::string(Args.getLastArgValue(OPT_o));
 302   Opts.SplitDwarfOutput =
 303       std::string(Args.getLastArgValue(OPT_split_dwarf_output));
 304   if (Arg *A = Args.getLastArg(OPT_filetype)) {
 305     StringRef Name = A->getValue();
 306     unsigned OutputType = StringSwitch<unsigned>(Name)
 307       .Case("asm", FT_Asm)
 308       .Case("null", FT_Null)
 309       .Case("obj", FT_Obj)
 310       .Default(~0U);
 311     if (OutputType == ~0U) {
 312       Diags.Report(diag::err_drv_invalid_value) << A->getAsString(Args) << Name;
 313       Success = false;
 314     } else
 315       Opts.OutputType = FileType(OutputType);
 316   }
 317   Opts.ShowHelp = Args.hasArg(OPT_help);
 318   Opts.ShowVersion = Args.hasArg(OPT_version);
 319
 320   // Transliterate Options
 321   Opts.OutputAsmVariant =
 322       getLastArgIntValue(Args, OPT_output_asm_variant, 0, Diags);
 323   Opts.ShowEncoding = Args.hasArg(OPT_show_encoding);
 324   Opts.ShowInst = Args.hasArg(OPT_show_inst);
 325
 326   // Assemble Options
 327   Opts.RelaxAll = Args.hasArg(OPT_mrelax_all);
 328   Opts.NoExecStack = Args.hasArg(OPT_mno_exec_stack);
 329   Opts.FatalWarnings = Args.hasArg(OPT_massembler_fatal_warnings);
 330   Opts.NoWarn = Args.hasArg(OPT_massembler_no_warn);
 331   Opts.NoTypeCheck = Args.hasArg(OPT_mno_type_check);
 332   Opts.RelocationModel =
 333       std::string(Args.getLastArgValue(OPT_mrelocation_model, "pic"));
 334   Opts.TargetABI = std::string(Args.getLastArgValue(OPT_target_abi));
 335   Opts.IncrementalLinkerCompatible =
 336       Args.hasArg(OPT_mincremental_linker_compatible);
 337   Opts.SymbolDefs = Args.getAllArgValues(OPT_defsym);
 338
 339   // EmbedBitcode Option. If -fembed-bitcode is enabled, set the flag.
 340   // EmbedBitcode behaves the same for all embed options for assembly files.
 341   if (auto *A = Args.getLastArg(OPT_fembed_bitcode_EQ)) {
 342     Opts.EmbedBitcode = llvm::StringSwitch<unsigned>(A->getValue())
 343                             .Case("all", 1)
 344                             .Case("bitcode", 1)
 345                             .Case("marker", 1)
 346                             .Default(0);
 347   }
 348
 349   if (auto *A = Args.getLastArg(OPT_femit_dwarf_unwind_EQ)) {
 350     Opts.EmitDwarfUnwind =
 351         llvm::StringSwitch<EmitDwarfUnwindType>(A->getValue())
 352             .Case("always", EmitDwarfUnwindType::Always)
 353             .Case("no-compact-unwind", EmitDwarfUnwindType::NoCompactUnwind)
 354             .Case("default", EmitDwarfUnwindType::Default);
 355   }
 356
 357   Opts.EmitCompactUnwindNonCanonical =
 358       Args.hasArg(OPT_femit_compact_unwind_non_canonical);
 359
 360   Opts.AsSecureLogFile = Args.getLastArgValue(OPT_as_secure_log_file);
 361
 362   return Success;
 363 }
 364
 365 static std::unique_ptr<raw_fd_ostream>
 366 getOutputStream(StringRef Path, DiagnosticsEngine &Diags, bool Binary) {
 367   // Make sure that the Out file gets unlinked from the disk if we get a
 368   // SIGINT.
 369   if (Path != "-")
 370     sys::RemoveFileOnSignal(Path);
 371
 372   std::error_code EC;
 373   auto Out = std::make_unique<raw_fd_ostream>(
 374       Path, EC, (Binary ? sys::fs::OF_None : sys::fs::OF_TextWithCRLF));
 375   if (EC) {
 376     Diags.Report(diag::err_fe_unable_to_open_output) << Path << EC.message();
 377     return nullptr;
 378   }
 379
 380   return Out;
 381 }
 382
 383 static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,
 384                                  DiagnosticsEngine &Diags) {
 385   // Get the target specific parser.
 386   std::string Error;
 387   const Target *TheTarget = TargetRegistry::lookupTarget(Opts.Triple, Error);
 388   if (!TheTarget)
 389     return Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
 390
 391   ErrorOr<std::unique_ptr<MemoryBuffer>> Buffer =
 392       MemoryBuffer::getFileOrSTDIN(Opts.InputFile, /*IsText=*/true);
 393
 394   if (std::error_code EC = Buffer.getError()) {
 395     return Diags.Report(diag::err_fe_error_reading)
 396            << Opts.InputFile << EC.message();
 397   }
 398
 399   SourceMgr SrcMgr;
 400
 401   // Tell SrcMgr about this buffer, which is what the parser will pick up.
 402   unsigned BufferIndex = SrcMgr.AddNewSourceBuffer(std::move(*Buffer), SMLoc());
 403
 404   // Record the location of the include directories so that the lexer can find
 405   // it later.
 406   SrcMgr.setIncludeDirs(Opts.IncludePaths);
 407
 408   std::unique_ptr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(Opts.Triple));
 409   assert(MRI && "Unable to create target register info!");
 410
 411   MCTargetOptions MCOptions;
 412   MCOptions.EmitDwarfUnwind = Opts.EmitDwarfUnwind;
 413   MCOptions.EmitCompactUnwindNonCanonical = Opts.EmitCompactUnwindNonCanonical;
 414   MCOptions.AsSecureLogFile = Opts.AsSecureLogFile;
 415
 416   std::unique_ptr<MCAsmInfo> MAI(
 417       TheTarget->createMCAsmInfo(*MRI, Opts.Triple, MCOptions));
 418   assert(MAI && "Unable to create target asm info!");
 419
 420   // Ensure MCAsmInfo initialization occurs before any use, otherwise sections
 421   // may be created with a combination of default and explicit settings.
 422   MAI->setCompressDebugSections(Opts.CompressDebugSections);
 423
 424   MAI->setRelaxELFRelocations(Opts.RelaxELFRelocations);
 425
 426   bool IsBinary = Opts.OutputType == AssemblerInvocation::FT_Obj;
 427   if (Opts.OutputPath.empty())
 428     Opts.OutputPath = "-";
 429   std::unique_ptr<raw_fd_ostream> FDOS =
 430       getOutputStream(Opts.OutputPath, Diags, IsBinary);
 431   if (!FDOS)
 432     return true;
 433   std::unique_ptr<raw_fd_ostream> DwoOS;
 434   if (!Opts.SplitDwarfOutput.empty())
 435     DwoOS = getOutputStream(Opts.SplitDwarfOutput, Diags, IsBinary);
 436
 437   // Build up the feature string from the target feature list.
 438   std::string FS = llvm::join(Opts.Features, ",");
 439
 440   std::unique_ptr<MCSubtargetInfo> STI(
 441       TheTarget->createMCSubtargetInfo(Opts.Triple, Opts.CPU, FS));
 442   assert(STI && "Unable to create subtarget info!");
 443
 444   MCContext Ctx(Triple(Opts.Triple), MAI.get(), MRI.get(), STI.get(), &SrcMgr,
 445                 &MCOptions);
 446
 447   bool PIC = false;
 448   if (Opts.RelocationModel == "static") {
 449     PIC = false;
 450   } else if (Opts.RelocationModel == "pic") {
 451     PIC = true;
 452   } else {
 453     assert(Opts.RelocationModel == "dynamic-no-pic" &&
 454            "Invalid PIC model!");
 455     PIC = false;
 456   }
 457
 458   // FIXME: This is not pretty. MCContext has a ptr to MCObjectFileInfo and
 459   // MCObjectFileInfo needs a MCContext reference in order to initialize itself.
 460   std::unique_ptr<MCObjectFileInfo> MOFI(
 461       TheTarget->createMCObjectFileInfo(Ctx, PIC));
 462   if (Opts.DarwinTargetVariantTriple)
 463     MOFI->setDarwinTargetVariantTriple(*Opts.DarwinTargetVariantTriple);
 464   if (!Opts.DarwinTargetVariantSDKVersion.empty())
 465     MOFI->setDarwinTargetVariantSDKVersion(Opts.DarwinTargetVariantSDKVersion);
 466   Ctx.setObjectFileInfo(MOFI.get());
 467
 468   if (Opts.SaveTemporaryLabels)
 469     Ctx.setAllowTemporaryLabels(false);
 470   if (Opts.GenDwarfForAssembly)
 471     Ctx.setGenDwarfForAssembly(true);
 472   if (!Opts.DwarfDebugFlags.empty())
 473     Ctx.setDwarfDebugFlags(StringRef(Opts.DwarfDebugFlags));
 474   if (!Opts.DwarfDebugProducer.empty())
 475     Ctx.setDwarfDebugProducer(StringRef(Opts.DwarfDebugProducer));
 476   if (!Opts.DebugCompilationDir.empty())
 477     Ctx.setCompilationDir(Opts.DebugCompilationDir);
 478   else {
 479     // If no compilation dir is set, try to use the current directory.
 480     SmallString<128> CWD;
 481     if (!sys::fs::current_path(CWD))
 482       Ctx.setCompilationDir(CWD);
 483   }
 484   if (!Opts.DebugPrefixMap.empty())
 485     for (const auto &KV : Opts.DebugPrefixMap)
 486       Ctx.addDebugPrefixMapEntry(KV.first, KV.second);
 487   if (!Opts.MainFileName.empty())
 488     Ctx.setMainFileName(StringRef(Opts.MainFileName));
 489   Ctx.setDwarfFormat(Opts.Dwarf64 ? dwarf::DWARF64 : dwarf::DWARF32);
 490   Ctx.setDwarfVersion(Opts.DwarfVersion);
 491   if (Opts.GenDwarfForAssembly)
 492     Ctx.setGenDwarfRootFile(Opts.InputFile,
 493                             SrcMgr.getMemoryBuffer(BufferIndex)->getBuffer());
 494
 495   std::unique_ptr<MCStreamer> Str;
 496
 497   std::unique_ptr<MCInstrInfo> MCII(TheTarget->createMCInstrInfo());
 498   assert(MCII && "Unable to create instruction info!");
 499
 500   raw_pwrite_stream *Out = FDOS.get();
 501   std::unique_ptr<buffer_ostream> BOS;
 502
 503   MCOptions.MCNoWarn = Opts.NoWarn;
 504   MCOptions.MCFatalWarnings = Opts.FatalWarnings;
 505   MCOptions.MCNoTypeCheck = Opts.NoTypeCheck;
 506   MCOptions.ABIName = Opts.TargetABI;
 507
 508   // FIXME: There is a bit of code duplication with addPassesToEmitFile.
 509   if (Opts.OutputType == AssemblerInvocation::FT_Asm) {
 510     MCInstPrinter *IP = TheTarget->createMCInstPrinter(
 511         llvm::Triple(Opts.Triple), Opts.OutputAsmVariant, *MAI, *MCII, *MRI);
 512
 513     std::unique_ptr<MCCodeEmitter> CE;
 514     if (Opts.ShowEncoding)
 515       CE.reset(TheTarget->createMCCodeEmitter(*MCII, Ctx));
 516     std::unique_ptr<MCAsmBackend> MAB(
 517         TheTarget->createMCAsmBackend(*STI, *MRI, MCOptions));
 518
 519     auto FOut = std::make_unique<formatted_raw_ostream>(*Out);
 520     Str.reset(TheTarget->createAsmStreamer(
 521         Ctx, std::move(FOut), /*asmverbose*/ true,
 522         /*useDwarfDirectory*/ true, IP, std::move(CE), std::move(MAB),
 523         Opts.ShowInst));
 524   } else if (Opts.OutputType == AssemblerInvocation::FT_Null) {
 525     Str.reset(createNullStreamer(Ctx));
 526   } else {
 527     assert(Opts.OutputType == AssemblerInvocation::FT_Obj &&
 528            "Invalid file type!");
 529     if (!FDOS->supportsSeeking()) {
 530       BOS = std::make_unique<buffer_ostream>(*FDOS);
 531       Out = BOS.get();
 532     }
 533
 534     std::unique_ptr<MCCodeEmitter> CE(
 535         TheTarget->createMCCodeEmitter(*MCII, Ctx));
 536     std::unique_ptr<MCAsmBackend> MAB(
 537         TheTarget->createMCAsmBackend(*STI, *MRI, MCOptions));
 538     assert(MAB && "Unable to create asm backend!");
 539
 540     std::unique_ptr<MCObjectWriter> OW =
 541         DwoOS ? MAB->createDwoObjectWriter(*Out, *DwoOS)
 542               : MAB->createObjectWriter(*Out);
 543
 544     Triple T(Opts.Triple);
 545     Str.reset(TheTarget->createMCObjectStreamer(
 546         T, Ctx, std::move(MAB), std::move(OW), std::move(CE), *STI,
 547         Opts.RelaxAll, Opts.IncrementalLinkerCompatible,
 548         /*DWARFMustBeAtTheEnd*/ true));
 549     Str.get()->initSections(Opts.NoExecStack, *STI);
 550   }
 551
 552   // When -fembed-bitcode is passed to clang_as, a 1-byte marker
 553   // is emitted in __LLVM,__asm section if the object file is MachO format.
 554   if (Opts.EmbedBitcode && Ctx.getObjectFileType() == MCContext::IsMachO) {
 555     MCSection *AsmLabel = Ctx.getMachOSection(
 556         "__LLVM", "__asm", MachO::S_REGULAR, 4, SectionKind::getReadOnly());
 557     Str.get()->switchSection(AsmLabel);
 558     Str.get()->emitZeros(1);
 559   }
 560
 561   // Assembly to object compilation should leverage assembly info.
 562   Str->setUseAssemblerInfoForParsing(true);
 563
 564   bool Failed = false;
 565
 566   std::unique_ptr<MCAsmParser> Parser(
 567       createMCAsmParser(SrcMgr, Ctx, *Str.get(), *MAI));
 568
 569   // FIXME: init MCTargetOptions from sanitizer flags here.
 570   std::unique_ptr<MCTargetAsmParser> TAP(
 571       TheTarget->createMCAsmParser(*STI, *Parser, *MCII, MCOptions));
 572   if (!TAP)
 573     Failed = Diags.Report(diag::err_target_unknown_triple) << Opts.Triple;
 574
 575   // Set values for symbols, if any.
 576   for (auto &S : Opts.SymbolDefs) {
 577     auto Pair = StringRef(S).split('=');
 578     auto Sym = Pair.first;
 579     auto Val = Pair.second;
 580     int64_t Value;
 581     // We have already error checked this in the driver.
 582     Val.getAsInteger(0, Value);
 583     Ctx.setSymbolValue(Parser->getStreamer(), Sym, Value);
 584   }
 585
 586   if (!Failed) {
 587     Parser->setTargetParser(*TAP.get());
 588     Failed = Parser->Run(Opts.NoInitialTextSection);
 589   }
 590
 591   return Failed;
 592 }
 593
 594 static bool ExecuteAssembler(AssemblerInvocation &Opts,
 595                              DiagnosticsEngine &Diags) {
 596   bool Failed = ExecuteAssemblerImpl(Opts, Diags);
 597
 598   // Delete output file if there were errors.
 599   if (Failed) {
 600     if (Opts.OutputPath != "-")
 601       sys::fs::remove(Opts.OutputPath);
 602     if (!Opts.SplitDwarfOutput.empty() && Opts.SplitDwarfOutput != "-")
 603       sys::fs::remove(Opts.SplitDwarfOutput);
 604   }
 605
 606   return Failed;
 607 }
 608
 609 static void LLVMErrorHandler(void *UserData, const char *Message,
 610                              bool GenCrashDiag) {
 611   DiagnosticsEngine &Diags = *static_cast<DiagnosticsEngine*>(UserData);
 612
 613   Diags.Report(diag::err_fe_error_backend) << Message;
 614
 615   // We cannot recover from llvm errors.
 616   sys::Process::Exit(1);
 617 }
 618
 619 int cc1as_main(ArrayRef<const char *> Argv, const char *Argv0, void *MainAddr) {
 620   // Initialize targets and assembly printers/parsers.
 621   InitializeAllTargetInfos();
 622   InitializeAllTargetMCs();
 623   InitializeAllAsmParsers();
 624
 625   // Construct our diagnostic client.
 626   IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
 627   TextDiagnosticPrinter *DiagClient
 628     = new TextDiagnosticPrinter(errs(), &*DiagOpts);
 629   DiagClient->setPrefix("clang -cc1as");
 630   IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
 631   DiagnosticsEngine Diags(DiagID, &*DiagOpts, DiagClient);
 632
 633   // Set an error handler, so that any LLVM backend diagnostics go through our
 634   // error handler.
 635   ScopedFatalErrorHandler FatalErrorHandler
 636     (LLVMErrorHandler, static_cast<void*>(&Diags));
 637
 638   // Parse the arguments.
 639   AssemblerInvocation Asm;
 640   if (!AssemblerInvocation::CreateFromArgs(Asm, Argv, Diags))
 641     return 1;
 642
 643   if (Asm.ShowHelp) {
 644     getDriverOptTable().printHelp(
 645         llvm::outs(), "clang -cc1as [options] file...",
 646         "Clang Integrated Assembler", /*ShowHidden=*/false,
 647         /*ShowAllAliases=*/false,
 648         llvm::opt::Visibility(driver::options::CC1AsOption));
 649
 650     return 0;
 651   }
 652
 653   // Honor -version.
 654   //
 655   // FIXME: Use a better -version message?
 656   if (Asm.ShowVersion) {
 657     llvm::cl::PrintVersionMessage();
 658     return 0;
 659   }
 660
 661   // Honor -mllvm.
 662   //
 663   // FIXME: Remove this, one day.
 664   if (!Asm.LLVMArgs.empty()) {
 665     unsigned NumArgs = Asm.LLVMArgs.size();
 666     auto Args = std::make_unique<const char*[]>(NumArgs + 2);
 667     Args[0] = "clang (LLVM option parsing)";
 668     for (unsigned i = 0; i != NumArgs; ++i)
 669       Args[i + 1] = Asm.LLVMArgs[i].c_str();
 670     Args[NumArgs + 1] = nullptr;
 671     llvm::cl::ParseCommandLineOptions(NumArgs + 1, Args.get());
 672   }
 673
 674   // Execute the invocation, unless there were parsing errors.
 675   bool Failed = Diags.hasErrorOccurred() || ExecuteAssembler(Asm, Diags);
 676
 677   // If any timers were active but haven't been destroyed yet, print their
 678   // results now.
 679   TimerGroup::printAll(errs());
 680   TimerGroup::clearAll();
 681
 682   return !!Failed;
 683 }