C++ SmallString::c_str方法代码示例

static std::string ProcessFailure(StringRef ProgPath, const char** Args,
                                  unsigned Timeout = 0,
                                  unsigned MemoryLimit = 0) {
  std::ostringstream OS;
  OS << "\nError running tool:\n ";
  for (const char **Arg = Args; *Arg; ++Arg)
    OS << " " << *Arg;
  OS << "\n";

  // Rerun the compiler, capturing any error messages to print them.
  SmallString<128> ErrorFilename;
  int ErrorFD;
  error_code EC = sys::fs::createTemporaryFile(
      "bugpoint.program_error_messages", "", ErrorFD, ErrorFilename);
  if (EC) {
    errs() << "Error making unique filename: " << EC.message() << "\n";
    exit(1);
  }
  RunProgramWithTimeout(ProgPath, Args, "", ErrorFilename.str(),
                        ErrorFilename.str(), Timeout, MemoryLimit);
  // FIXME: check return code ?

  // Print out the error messages generated by GCC if possible...
  std::ifstream ErrorFile(ErrorFilename.c_str());
  if (ErrorFile) {
    std::copy(std::istreambuf_iterator<char>(ErrorFile),
              std::istreambuf_iterator<char>(),
              std::ostreambuf_iterator<char>(OS));
    ErrorFile.close();
  }

  sys::fs::remove(ErrorFilename.c_str());
  return OS.str();
}

// Implement the 'x' operation. This function extracts files back to the file
// system.
static void doExtract(StringRef Name, object::Archive::child_iterator I) {
  // Retain the original mode.
  sys::fs::perms Mode = I->getAccessMode();
  SmallString<128> Storage = Name;

  int FD;
  failIfError(
      sys::fs::openFileForWrite(Storage.c_str(), FD, sys::fs::F_None, Mode),
      Storage.c_str());

  {
    raw_fd_ostream file(FD, false);

    // Get the data and its length
    StringRef Data = I->getBuffer();

    // Write the data.
    file.write(Data.data(), Data.size());
  }

  // If we're supposed to retain the original modification times, etc. do so
  // now.
  if (OriginalDates)
    failIfError(
        sys::fs::setLastModificationAndAccessTime(FD, I->getLastModified()));

  if (close(FD))
    fail("Could not close the file");
}

bool LTOCodeGenerator::compileOptimizedToFile(const char **name,
                                              std::string &errMsg) {
  // make unique temp .o file to put generated object file
  SmallString<128> Filename;
  int FD;
  std::error_code EC =
      sys::fs::createTemporaryFile("lto-llvm", "o", FD, Filename);
  if (EC) {
    errMsg = EC.message();
    return false;
  }

  // generate object file
  tool_output_file objFile(Filename.c_str(), FD);

  bool genResult = compileOptimized(objFile.os(), errMsg);
  objFile.os().close();
  if (objFile.os().has_error()) {
    objFile.os().clear_error();
    sys::fs::remove(Twine(Filename));
    return false;
  }

  objFile.keep();
  if (!genResult) {
    sys::fs::remove(Twine(Filename));
    return false;
  }

  NativeObjectPath = Filename.c_str();
  *name = NativeObjectPath.c_str();
  return true;
}

std::unique_ptr<Module>
BugDriver::extractMappedBlocksFromModule(const std::vector<BasicBlock *> &BBs,
                                         Module *M) {
  SmallString<128> Filename;
  int FD;
  std::error_code EC = sys::fs::createUniqueFile(
      OutputPrefix + "-extractblocks%%%%%%%", FD, Filename);
  if (EC) {
    outs() << "*** Basic Block extraction failed!\n";
    errs() << "Error creating temporary file: " << EC.message() << "\n";
    EmitProgressBitcode(M, "basicblockextractfail", true);
    return nullptr;
  }
  sys::RemoveFileOnSignal(Filename);

  tool_output_file BlocksToNotExtractFile(Filename.c_str(), FD);
  for (std::vector<BasicBlock*>::const_iterator I = BBs.begin(), E = BBs.end();
       I != E; ++I) {
    BasicBlock *BB = *I;
    // If the BB doesn't have a name, give it one so we have something to key
    // off of.
    if (!BB->hasName()) BB->setName("tmpbb");
    BlocksToNotExtractFile.os() << BB->getParent()->getName() << " "
                                << BB->getName() << "\n";
  }
  BlocksToNotExtractFile.os().close();
  if (BlocksToNotExtractFile.os().has_error()) {
    errs() << "Error writing list of blocks to not extract\n";
    EmitProgressBitcode(M, "basicblockextractfail", true);
    BlocksToNotExtractFile.os().clear_error();
    return nullptr;
  }
  BlocksToNotExtractFile.keep();

  std::string uniqueFN = "--extract-blocks-file=";
  uniqueFN += Filename.str();
  const char *ExtraArg = uniqueFN.c_str();

  std::vector<std::string> PI;
  PI.push_back("extract-blocks");
  std::unique_ptr<Module> Ret = runPassesOn(M, PI, false, 1, &ExtraArg);

  sys::fs::remove(Filename.c_str());

  if (!Ret) {
    outs() << "*** Basic Block extraction failed, please report a bug!\n";
    EmitProgressBitcode(M, "basicblockextractfail", true);
  }
  return Ret;
}

bool ReplacementHandling::serializeReplacements(
    const TUReplacementsMap &Replacements) {
  assert(!DestinationDir.empty() && "Destination directory not set");

  bool Errors = false;

  for (TUReplacementsMap::const_iterator I = Replacements.begin(),
                                         E = Replacements.end();
       I != E; ++I) {
    SmallString<128> ReplacementsFileName;
    SmallString<64> Error;
    bool Result = generateReplacementsFileName(DestinationDir,
                                               I->getValue().MainSourceFile,
                                               ReplacementsFileName, Error);
    if (!Result) {
      errs() << "Failed to generate replacements filename:" << Error << "\n";
      Errors = true;
      continue;
    }

    std::string ErrorInfo;
    raw_fd_ostream ReplacementsFile(ReplacementsFileName.c_str(), ErrorInfo,
                                    fs::F_None);
    if (!ErrorInfo.empty()) {
      errs() << "Error opening file: " << ErrorInfo << "\n";
      Errors = true;
      continue;
    }
    yaml::Output YAML(ReplacementsFile);
    YAML << const_cast<TranslationUnitReplacements &>(I->getValue());
  }
  return !Errors;
}

llvm::GlobalVariable *
MSRTTIBuilder::getBaseClassArray(SmallVectorImpl<MSRTTIClass> &Classes) {
  SmallString<256> MangledName;
  {
    llvm::raw_svector_ostream Out(MangledName);
    Mangler.mangleCXXRTTIBaseClassArray(RD, Out);
  }

  // Forward-declare the base class array.
  // cl.exe pads the base class array with 1 (in 32 bit mode) or 4 (in 64 bit
  // mode) bytes of padding.  We provide a pointer sized amount of padding by
  // adding +1 to Classes.size().  The sections have pointer alignment and are
  // marked pick-any so it shouldn't matter.
  auto PtrType = getBaseClassDescriptorType(CGM)->getPointerTo();
  auto ArrayType = llvm::ArrayType::get(PtrType, Classes.size() + 1);
  auto BCA = new llvm::GlobalVariable(Module, ArrayType,
      /*Constant=*/true, Linkage, /*Initializer=*/0, MangledName.c_str());

  // Initialize the BaseClassArray.
  SmallVector<llvm::Constant *, 8> BaseClassArrayData;
  for (MSRTTIClass &Class : Classes)
    BaseClassArrayData.push_back(getBaseClassDescriptor(Class));
  BaseClassArrayData.push_back(llvm::ConstantPointerNull::get(PtrType));
  BCA->setInitializer(llvm::ConstantArray::get(ArrayType, BaseClassArrayData));
  return BCA;
}

// This method allows an ArchiveMember to be replaced with the data for a
// different file, presumably as an update to the member. It also makes sure
// the flags are reset correctly.
bool ArchiveMember::replaceWith(StringRef newFile, std::string* ErrMsg) {
  bool Exists;
  if (sys::fs::exists(newFile.str(), Exists) || !Exists) {
    if (ErrMsg)
      *ErrMsg = "Can not replace an archive member with a non-existent file";
    return true;
  }

  data = 0;
  path = newFile.str();

  // SVR4 symbol tables have an empty name
  if (path == ARFILE_SVR4_SYMTAB_NAME)
    flags |= SVR4SymbolTableFlag;
  else
    flags &= ~SVR4SymbolTableFlag;

  // BSD4.4 symbol tables have a special name
  if (path == ARFILE_BSD4_SYMTAB_NAME)
    flags |= BSD4SymbolTableFlag;
  else
    flags &= ~BSD4SymbolTableFlag;

  // String table name
  if (path == ARFILE_STRTAB_NAME)
    flags |= StringTableFlag;
  else
    flags &= ~StringTableFlag;

  // If it has a slash or its over 15 chars then its a long filename format
  if (path.length() > 15)
    flags |= HasLongFilenameFlag;
  else
    flags &= ~HasLongFilenameFlag;

  // Get the signature and status info
  const char* signature = (const char*) data;
  SmallString<4> magic;
  if (!signature) {
    sys::fs::get_magic(path, magic.capacity(), magic);
    signature = magic.c_str();

    sys::fs::file_status Status;
    error_code EC = sys::fs::status(path, Status);
    if (EC)
      return true;

    User = Status.getUser();
    Group = Status.getGroup();
    Mode = Status.permissions();
    ModTime = Status.getLastModificationTime();

    // FIXME: On posix this is a second stat.
    EC = sys::fs::file_size(path, Size);
    if (EC)
      return true;
  }

  return false;
}

/// Add a symbol which isn't defined just yet to a list to be resolved later.
void LTOModule::addPotentialUndefinedSymbol(ModuleSymbolTable::Symbol Sym,
                                            bool isFunc) {
  SmallString<64> name;
  {
    raw_svector_ostream OS(name);
    SymTab.printSymbolName(OS, Sym);
    name.c_str();
  }

  auto IterBool = _undefines.insert(std::make_pair(name, NameAndAttributes()));

  // we already have the symbol
  if (!IterBool.second)
    return;

  NameAndAttributes &info = IterBool.first->second;

  info.name = IterBool.first->first();

  const GlobalValue *decl = Sym.dyn_cast<GlobalValue *>();

  if (decl->hasExternalWeakLinkage())
    info.attributes = LTO_SYMBOL_DEFINITION_WEAKUNDEF;
  else
    info.attributes = LTO_SYMBOL_DEFINITION_UNDEFINED;

  info.isFunction = isFunc;
  info.symbol = decl;
}

/// parseSymbols - Parse the symbols from the module and model-level ASM and add
/// them to either the defined or undefined lists.
bool LTOModule::parseSymbols(std::string &errMsg) {
  for (auto &Sym : IRFile->symbols()) {
    const GlobalValue *GV = IRFile->getSymbolGV(Sym.getRawDataRefImpl());
    uint32_t Flags = Sym.getFlags();
    if (Flags & object::BasicSymbolRef::SF_FormatSpecific)
      continue;

    bool IsUndefined = Flags & object::BasicSymbolRef::SF_Undefined;

    if (!GV) {
      SmallString<64> Buffer;
      {
        raw_svector_ostream OS(Buffer);
        Sym.printName(OS);
      }
      const char *Name = Buffer.c_str();

      if (IsUndefined)
        addAsmGlobalSymbolUndef(Name);
      else if (Flags & object::BasicSymbolRef::SF_Global)
        addAsmGlobalSymbol(Name, LTO_SYMBOL_SCOPE_DEFAULT);
      else
        addAsmGlobalSymbol(Name, LTO_SYMBOL_SCOPE_INTERNAL);
      continue;
    }

    auto *F = dyn_cast<Function>(GV);
    if (IsUndefined) {
      addPotentialUndefinedSymbol(Sym, F != nullptr);
      continue;
    }

    if (F) {
      addDefinedFunctionSymbol(Sym);
      continue;
    }

    if (isa<GlobalVariable>(GV)) {
      addDefinedDataSymbol(Sym);
      continue;
    }

    assert(isa<GlobalAlias>(GV));
    addDefinedDataSymbol(Sym);
  }

  // make symbols for all undefines
  for (StringMap<NameAndAttributes>::iterator u =_undefines.begin(),
         e = _undefines.end(); u != e; ++u) {
    // If this symbol also has a definition, then don't make an undefine because
    // it is a tentative definition.
    if (_defines.count(u->getKey())) continue;
    NameAndAttributes info = u->getValue();
    _symbols.push_back(info);
  }

  return false;
}

/// Launch each module's backend pipeline in a separate task in a thread pool.
static void thinLTOBackends(raw_fd_ostream *ApiFile,
                            const ModuleSummaryIndex &CombinedIndex) {
  unsigned TaskCount = 0;
  std::vector<ThinLTOTaskInfo> Tasks;
  Tasks.reserve(Modules.size());
  unsigned int MaxThreads = options::Parallelism
                                ? options::Parallelism
                                : thread::hardware_concurrency();

  // Create ThreadPool in nested scope so that threads will be joined
  // on destruction.
  {
    ThreadPool ThinLTOThreadPool(MaxThreads);
    for (claimed_file &F : Modules) {
      // Do all the gold callbacks in the main thread, since gold is not thread
      // safe by default.
      PluginInputFile InputFile(F.handle);
      const void *View = getSymbolsAndView(F);
      if (!View)
        continue;

      SmallString<128> Filename;
      if (!options::obj_path.empty())
        // Note that openOutputFile will append a unique ID for each task
        Filename = options::obj_path;
      else if (options::TheOutputType == options::OT_SAVE_TEMPS) {
        // Use the input file name so that we get a unique and identifiable
        // output file for each ThinLTO backend task.
        Filename = InputFile.file().name;
        Filename += ".thinlto.o";
      }
      bool TempOutFile = Filename.empty();

      SmallString<128> NewFilename;
      int FD = openOutputFile(Filename, TempOutFile, NewFilename,
                              // Only append the TaskID if we will use the
                              // non-unique obj_path.
                              !options::obj_path.empty() ? TaskCount : -1);
      TaskCount++;
      std::unique_ptr<raw_fd_ostream> OS =
          llvm::make_unique<raw_fd_ostream>(FD, true);

      // Enqueue the task
      ThinLTOThreadPool.async(thinLTOBackendTask, std::ref(F), View,
                              std::ref(InputFile.file()), ApiFile,
                              std::ref(CombinedIndex), OS.get(), TaskCount);

      // Record the information needed by the task or during its cleanup
      // to a ThinLTOTaskInfo instance. For information needed by the task
      // the unique_ptr ownership is transferred to the ThinLTOTaskInfo.
      Tasks.emplace_back(std::move(InputFile), std::move(OS),
                         NewFilename.c_str(), TempOutFile);
    }
  }

  for (auto &Task : Tasks)
    Task.cleanup();
}

void CodeGen::runSplitCodeGen(const SmallString<128> &BCFilename) {
  const std::string &TripleStr = M->getTargetTriple();
  Triple TheTriple(TripleStr);

  SubtargetFeatures Features = getFeatures(TheTriple);

  TargetOptions Options = InitTargetOptionsFromCodeGenFlags();
  CodeGenOpt::Level CGOptLevel = getCGOptLevel();

  SmallString<128> Filename;
  // Note that openOutputFile will append a unique ID for each task
  if (!options::obj_path.empty())
    Filename = options::obj_path;
  else if (options::TheOutputType == options::OT_SAVE_TEMPS)
    Filename = output_name + ".o";

  // Note that the default parallelism is 1 instead of the
  // hardware_concurrency, as there are behavioral differences between
  // parallelism levels (e.g. symbol ordering will be different, and some uses
  // of inline asm currently have issues with parallelism >1).
  unsigned int MaxThreads = options::Parallelism ? options::Parallelism : 1;

  std::vector<SmallString<128>> Filenames(MaxThreads);
  std::vector<SmallString<128>> BCFilenames(MaxThreads);
  bool TempOutFile = Filename.empty();
  {
    // Open a file descriptor for each backend task. This is done in a block
    // so that the output file descriptors are closed before gold opens them.
    std::list<llvm::raw_fd_ostream> OSs;
    std::vector<llvm::raw_pwrite_stream *> OSPtrs(MaxThreads);
    for (unsigned I = 0; I != MaxThreads; ++I) {
      int FD = openOutputFile(Filename, TempOutFile, Filenames[I],
                              // Only append ID if there are multiple tasks.
                              MaxThreads > 1 ? I : -1);
      OSs.emplace_back(FD, true);
      OSPtrs[I] = &OSs.back();
    }

    std::list<llvm::raw_fd_ostream> BCOSs;
    std::vector<llvm::raw_pwrite_stream *> BCOSPtrs;
    if (!BCFilename.empty() && MaxThreads > 1) {
      for (unsigned I = 0; I != MaxThreads; ++I) {
        int FD = openOutputFile(BCFilename, false, BCFilenames[I], I);
        BCOSs.emplace_back(FD, true);
        BCOSPtrs.push_back(&BCOSs.back());
      }
    }

    // Run backend tasks.
    splitCodeGen(std::move(M), OSPtrs, BCOSPtrs, options::mcpu, Features.getString(),
                 Options, RelocationModel, CodeModel::Default, CGOptLevel);
  }

  for (auto &Filename : Filenames)
    recordFile(Filename.c_str(), TempOutFile);
}

void LTOModule::addDefinedDataSymbol(const object::BasicSymbolRef &Sym) {
  SmallString<64> Buffer;
  {
    raw_svector_ostream OS(Buffer);
    Sym.printName(OS);
  }

  const GlobalValue *V = IRFile->getSymbolGV(Sym.getRawDataRefImpl());
  addDefinedDataSymbol(Buffer.c_str(), V);
}

void LTOModule::addDefinedFunctionSymbol(ModuleSymbolTable::Symbol Sym) {
  SmallString<64> Buffer;
  {
    raw_svector_ostream OS(Buffer);
    SymTab.printSymbolName(OS, Sym);
    Buffer.c_str();
  }

  const Function *F = cast<Function>(Sym.get<GlobalValue *>());
  addDefinedFunctionSymbol(Buffer, F);
}

void LTOModule::addDefinedDataSymbol(ModuleSymbolTable::Symbol Sym) {
  SmallString<64> Buffer;
  {
    raw_svector_ostream OS(Buffer);
    SymTab.printSymbolName(OS, Sym);
    Buffer.c_str();
  }

  const GlobalValue *V = Sym.get<GlobalValue *>();
  addDefinedDataSymbol(Buffer, V);
}

void LTOModule::addDefinedFunctionSymbol(const object::BasicSymbolRef &Sym) {
  SmallString<64> Buffer;
  {
    raw_svector_ostream OS(Buffer);
    Sym.printName(OS);
  }

  const Function *F =
      cast<Function>(IRFile->getSymbolGV(Sym.getRawDataRefImpl()));
  addDefinedFunctionSymbol(Buffer.c_str(), F);
}