C++ Path::isEmpty方法代码示例

bool LTOCodeGenerator::assemble(const std::string& asmPath, 
                                const std::string& objPath, std::string& errMsg)
{
    // find compiler driver
    const sys::Path gcc = sys::Program::FindProgramByName("gcc");
    if ( gcc.isEmpty() ) {
        errMsg = "can't locate gcc";
        return true;
    }

    // build argument list
    std::vector<const char*> args;
    std::string targetTriple = _linker.getModule()->getTargetTriple();
    args.push_back(gcc.c_str());
    if ( targetTriple.find("darwin") != targetTriple.size() ) {
        if (strncmp(targetTriple.c_str(), "i686-apple-", 11) == 0) {
            args.push_back("-arch");
            args.push_back("i386");
        }
        else if (strncmp(targetTriple.c_str(), "x86_64-apple-", 13) == 0) {
            args.push_back("-arch");
            args.push_back("x86_64");
        }
        else if (strncmp(targetTriple.c_str(), "powerpc-apple-", 14) == 0) {
            args.push_back("-arch");
            args.push_back("ppc");
        }
        else if (strncmp(targetTriple.c_str(), "powerpc64-apple-", 16) == 0) {
            args.push_back("-arch");
            args.push_back("ppc64");
        }
    }
    args.push_back("-c");
    args.push_back("-x");
    args.push_back("assembler");
    args.push_back("-o");
    args.push_back(objPath.c_str());
    args.push_back(asmPath.c_str());
    args.push_back(0);

    // invoke assembler
    if ( sys::Program::ExecuteAndWait(gcc, &args[0], 0, 0, 0, 0, &errMsg) ) {
        errMsg = "error in assembly";    
        return true;
    }
    return false; // success
}

///Link all modules together and optimize them using IPO. Generate
/// native object file using OutputFilename
/// Return appropriate LTOStatus.
enum LTOStatus
LTO::optimizeModules(const std::string &OutputFilename,
                     std::vector<const char *> &exportList,
                     std::string &targetTriple,
                     bool saveTemps, const char *FinalOutputFilename)
{
  if (modules.empty())
    return LTO_NO_WORK;

  std::ios::openmode io_mode = 
    std::ios::out | std::ios::trunc | std::ios::binary; 
  std::string *errMsg = NULL;
  Module *bigOne = modules[0];
  Linker theLinker("LinkTimeOptimizer", bigOne, false);
  for (unsigned i = 1, e = modules.size(); i != e; ++i)
    if (theLinker.LinkModules(bigOne, modules[i], errMsg))
      return LTO_MODULE_MERGE_FAILURE;
  //  all modules have been handed off to the linker.
  modules.clear();

  sys::Path FinalOutputPath(FinalOutputFilename);
  FinalOutputPath.eraseSuffix();

  switch(CGModel) {
  case LTO_CGM_Dynamic:
    Target->setRelocationModel(Reloc::PIC_);
    break;
  case LTO_CGM_DynamicNoPIC:
    Target->setRelocationModel(Reloc::DynamicNoPIC);
    break;
  case LTO_CGM_Static:
    Target->setRelocationModel(Reloc::Static);
    break;
  }

  if (saveTemps) {
    std::string tempFileName(FinalOutputPath.c_str());
    tempFileName += "0.bc";
    std::ofstream Out(tempFileName.c_str(), io_mode);
    WriteBitcodeToFile(bigOne, Out);
  }

  // Strip leading underscore because it was added to match names
  // seen by linker.
  for (unsigned i = 0, e = exportList.size(); i != e; ++i) {
    const char *name = exportList[i];
    NameToSymbolMap::iterator itr = allSymbols.find(name);
    if (itr != allSymbols.end())
      exportList[i] = allSymbols[name]->getName();
  }


  std::string ErrMsg;
  sys::Path TempDir = sys::Path::GetTemporaryDirectory(&ErrMsg);
  if (TempDir.isEmpty()) {
    cerr << "lto: " << ErrMsg << "\n";
    return LTO_WRITE_FAILURE;
  }
  sys::Path tmpAsmFilePath(TempDir);
  if (!tmpAsmFilePath.appendComponent("lto")) {
    cerr << "lto: " << ErrMsg << "\n";
    TempDir.eraseFromDisk(true);
    return LTO_WRITE_FAILURE;
  }
  if (tmpAsmFilePath.createTemporaryFileOnDisk(true, &ErrMsg)) {
    cerr << "lto: " << ErrMsg << "\n";
    TempDir.eraseFromDisk(true);
    return LTO_WRITE_FAILURE;
  }
  sys::RemoveFileOnSignal(tmpAsmFilePath);

  std::ofstream asmFile(tmpAsmFilePath.c_str(), io_mode);
  if (!asmFile.is_open() || asmFile.bad()) {
    if (tmpAsmFilePath.exists()) {
      tmpAsmFilePath.eraseFromDisk();
      TempDir.eraseFromDisk(true);
    }
    return LTO_WRITE_FAILURE;
  }

  enum LTOStatus status = optimize(bigOne, asmFile, exportList);
  asmFile.close();
  if (status != LTO_OPT_SUCCESS) {
    tmpAsmFilePath.eraseFromDisk();
    TempDir.eraseFromDisk(true);
    return status;
  }

  if (saveTemps) {
    std::string tempFileName(FinalOutputPath.c_str());
    tempFileName += "1.bc";
    std::ofstream Out(tempFileName.c_str(), io_mode);
    WriteBitcodeToFile(bigOne, Out);
  }

  targetTriple = bigOne->getTargetTriple();

//.........这里部分代码省略.........