C++ ArrayRef::front方法代码示例

static Variable::RangeList
MakeRangeList(const PdbIndex &index, const LocalVariableAddrRange &range,
              llvm::ArrayRef<LocalVariableAddrGap> gaps) {
  lldb::addr_t start =
      index.MakeVirtualAddress(range.ISectStart, range.OffsetStart);
  lldb::addr_t end = start + range.Range;

  Variable::RangeList result;
  while (!gaps.empty()) {
    const LocalVariableAddrGap &gap = gaps.front();

    lldb::addr_t size = gap.GapStartOffset - start;
    result.Append(start, size);
    start += gap.Range;
    gaps = gaps.drop_front();
  }

  result.Append(start, end - start);
  return result;
}

void BuildSystemInvocation::parse(llvm::ArrayRef<std::string> args,
                                  llvm::SourceMgr& sourceMgr) {
  auto error = [&](const Twine &message) {
    sourceMgr.PrintMessage(llvm::SMLoc{}, llvm::SourceMgr::DK_Error, message);
    hadErrors = true;
  };

  while (!args.empty()) {
    const auto& option = args.front();
    args = args.slice(1);

    if (option == "-") {
      for (const auto& arg: args) {
        positionalArgs.push_back(arg);
      }
      break;
    }

    if (!option.empty() && option[0] != '-') {
      positionalArgs.push_back(option);
      continue;
    }
    
    if (option == "--help") {
      showUsage = true;
      break;
    } else if (option == "--version") {
      showVersion = true;
      break;
    } else if (option == "--no-db") {
      dbPath = "";
    } else if (option == "--db") {
      if (args.empty()) {
        error("missing argument to '" + option + "'");
        break;
      }
      dbPath = args[0];
      args = args.slice(1);
    } else if (option == "-C" || option == "--chdir") {
      if (args.empty()) {
        error("missing argument to '" + option + "'");
        break;
      }
      chdirPath = args[0];
      args = args.slice(1);
    } else if (option == "-f") {
      if (args.empty()) {
        error("missing argument to '" + option + "'");
        break;
      }
      buildFilePath = args[0];
      args = args.slice(1);
    } else if (option == "--serial") {
      useSerialBuild = true;
    } else if (option == "-v" || option == "--verbose") {
      showVerboseStatus = true;
    } else if (option == "--trace") {
      if (args.empty()) {
        error("missing argument to '" + option + "'");
        break;
      }
      traceFilePath = args[0];
      args = args.slice(1);
    } else {
      error("invalid option '" + option + "'");
      break;
    }
  }
}

llvm::Error AllTUsToolExecutor::execute(
    llvm::ArrayRef<
        std::pair<std::unique_ptr<FrontendActionFactory>, ArgumentsAdjuster>>
        Actions) {
  if (Actions.empty())
    return make_string_error("No action to execute.");

  if (Actions.size() != 1)
    return make_string_error(
        "Only support executing exactly 1 action at this point.");

  std::string ErrorMsg;
  std::mutex TUMutex;
  auto AppendError = [&](llvm::Twine Err) {
    std::unique_lock<std::mutex> LockGuard(TUMutex);
    ErrorMsg += Err.str();
  };

  auto Log = [&](llvm::Twine Msg) {
    std::unique_lock<std::mutex> LockGuard(TUMutex);
    llvm::errs() << Msg.str() << "\n";
  };

  std::vector<std::string> Files;
  llvm::Regex RegexFilter(Filter);
  for (const auto& File : Compilations.getAllFiles()) {
    if (RegexFilter.match(File))
      Files.push_back(File);
  }
  // Add a counter to track the progress.
  const std::string TotalNumStr = std::to_string(Files.size());
  unsigned Counter = 0;
  auto Count = [&]() {
    std::unique_lock<std::mutex> LockGuard(TUMutex);
    return ++Counter;
  };

  auto &Action = Actions.front();

  {
    llvm::ThreadPool Pool(ThreadCount == 0 ? llvm::hardware_concurrency()
                                           : ThreadCount);
    llvm::SmallString<128> InitialWorkingDir;
    if (auto EC = llvm::sys::fs::current_path(InitialWorkingDir)) {
      InitialWorkingDir = "";
      llvm::errs() << "Error while getting current working directory: "
                   << EC.message() << "\n";
    }
    for (std::string File : Files) {
      Pool.async(
          [&](std::string Path) {
            Log("[" + std::to_string(Count()) + "/" + TotalNumStr +
                "] Processing file " + Path);
            ClangTool Tool(Compilations, {Path});
            Tool.appendArgumentsAdjuster(Action.second);
            Tool.appendArgumentsAdjuster(getDefaultArgumentsAdjusters());
            for (const auto &FileAndContent : OverlayFiles)
              Tool.mapVirtualFile(FileAndContent.first(),
                                  FileAndContent.second);
            // Do not restore working dir from multiple threads to avoid races.
            Tool.setRestoreWorkingDir(false);
            if (Tool.run(Action.first.get()))
              AppendError(llvm::Twine("Failed to run action on ") + Path +
                          "\n");
          },
          File);
    }
    // Make sure all tasks have finished before resetting the working directory.
    Pool.wait();
    if (!InitialWorkingDir.empty()) {
      if (auto EC = llvm::sys::fs::set_current_path(InitialWorkingDir))
        llvm::errs() << "Error while restoring working directory: "
                     << EC.message() << "\n";
    }
  }

  if (!ErrorMsg.empty())
    return make_string_error(ErrorMsg);

  return llvm::Error::success();
}

StatementPtr desugarCatchBlocks(llvm::ArrayRef<CatchPtr> catchBlocks,
                                CompilerState* cst) {
    assert(!catchBlocks.empty());
    Location firstCatchLocation = catchBlocks.front()->location;
    IdentifierPtr expVar = Identifier::get("%exp", firstCatchLocation);

    CallPtr activeException = new Call(primitive_expr_activeException(cst), new ExprList());
    activeException->location = firstCatchLocation;

    BindingPtr expBinding =
        new Binding(VAR,
                    identVtoFormalV(vector<IdentifierPtr>(1, expVar)),
                    new ExprList(activeException.ptr()));
    expBinding->location = firstCatchLocation;

    bool lastWasAny = false;
    IfPtr lastIf;
    StatementPtr result;
    for (size_t i = 0; i < catchBlocks.size(); ++i) {
        CatchPtr x = catchBlocks[i];
        if (lastWasAny)
            error(x, "unreachable catch block");
        if (x->exceptionType.ptr()) {
            ExprListPtr asTypeArgs = new ExprList(x->exceptionType);
            ExprPtr expVarName = new NameRef(expVar);
            expVarName->location = x->exceptionVar->location;
            asTypeArgs->add(expVarName);
            CallPtr cond = new Call(operator_expr_exceptionIsP(cst), asTypeArgs);
            cond->location = x->exceptionType->location;

            BlockPtr block = new Block();
            block->location = x->location;

            vector<IdentifierPtr> identifiers;
            makeExceptionVars(identifiers, x);

            CallPtr getter = new Call(operator_expr_exceptionAs(cst), asTypeArgs);
            getter->location = x->exceptionVar->location;
            BindingPtr binding =
                new Binding(VAR,
                            identVtoFormalV(identifiers),
                            new ExprList(getter.ptr()));
            binding->location = x->exceptionVar->location;

            BindingPtr exceptionVarForRethrow =
                new Binding(REF,
                            identVtoFormalV(vector<IdentifierPtr>(1, Identifier::get("%exception", x->location))),
                            new ExprList(new NameRef(Identifier::get(x->exceptionVar->str, x->location))));
            exceptionVarForRethrow->location = x->exceptionVar->location;

            block->statements.push_back(binding.ptr());
            block->statements.push_back(exceptionVarForRethrow.ptr());
            block->statements.push_back(x->body);

            IfPtr ifStatement = new If(cond.ptr(), block.ptr());
            ifStatement->location = x->location;
            if (!result)
                result = ifStatement.ptr();
            if (lastIf.ptr())
                lastIf->elsePart = ifStatement.ptr();
            lastIf = ifStatement;
        }
        else {
            BlockPtr block = new Block();
            block->location = x->location;

            vector<IdentifierPtr> identifiers;
            makeExceptionVars(identifiers, x);

            ExprListPtr asAnyArgs = new ExprList(new NameRef(expVar));
            CallPtr getter = new Call(operator_expr_exceptionAsAny(cst),
                                      asAnyArgs);
            getter->location = x->exceptionVar->location;
            BindingPtr binding =
                new Binding(VAR,
                            identVtoFormalV(identifiers),
                            new ExprList(getter.ptr()));
            binding->location = x->exceptionVar->location;

            BindingPtr exceptionVarForRethrow =
                new Binding(REF,
                            identVtoFormalV(vector<IdentifierPtr>(1, Identifier::get("%exception", x->location))),
                            new ExprList(new NameRef(Identifier::get(x->exceptionVar->str, x->location))));
            exceptionVarForRethrow->location = x->exceptionVar->location;

            block->statements.push_back(binding.ptr());
            block->statements.push_back(exceptionVarForRethrow.ptr());
            block->statements.push_back(x->body);

            if (!result)
                result = block.ptr();
            if (lastIf.ptr())
                lastIf->elsePart = block.ptr();

            lastWasAny = true;
            lastIf = NULL;
        }
    }
    assert(result.ptr());
    if (!lastWasAny) {
//.........这里部分代码省略.........