Index: CMakeLists.txt
===================================================================
--- CMakeLists.txt
+++ CMakeLists.txt
@@ -1,5 +1,6 @@
 add_subdirectory(clang-apply-replacements)
 add_subdirectory(clang-rename)
+add_subdirectory(clang-refactor)
 add_subdirectory(clang-reorder-fields)
 add_subdirectory(modularize)
 if(CLANG_ENABLE_STATIC_ANALYZER)
@@ -24,4 +25,3 @@
 if( CLANG_TOOLS_EXTRA_INCLUDE_DOCS )
   add_subdirectory(docs)
 endif()
-
Index: clang-refactor/CMakeLists.txt
===================================================================
--- /dev/null
+++ clang-refactor/CMakeLists.txt
@@ -0,0 +1,4 @@
+include_directories(core)
+
+add_subdirectory(core)
+add_subdirectory(driver)
Index: clang-refactor/core/BasicExecutor.h
===================================================================
--- /dev/null
+++ clang-refactor/core/BasicExecutor.h
@@ -0,0 +1,36 @@
+//===--- BasicExecutor.h - clang-refactor -----------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_BASIC_EXECUTOR_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_BASIC_EXECUTOR_H
+
+#include "Executor.h"
+#include "clang/Basic/LLVM.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Error.h"
+#include <string>
+#include <vector>
+
+namespace clang {
+namespace refactor {
+
+class BasicExecutor : public Executor {
+public:
+  void addTask(StringRef TU, const RefactoringOptions &Opts);
+
+  llvm::Error runTasks();
+private:
+  std::vector<std::pair<std::string, RefactoringOptions>> Tasks;
+};
+
+} // end namespace refactor
+} // end namespace refactor
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_BASIC_EXECUTOR
Index: clang-refactor/core/BasicExecutor.cpp
===================================================================
--- /dev/null
+++ clang-refactor/core/BasicExecutor.cpp
@@ -0,0 +1,30 @@
+//===--- BasicExecutor.cpp - clang-refactor ---------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "BasicExecutor.h"
+
+namespace clang {
+namespace refactor {
+
+void BasicExecutor::addTask(StringRef TU,
+                            const RefactoringOptions &Opts) {
+  Tasks.push_back({TU, Opts});
+}
+
+llvm::Error BasicExecutor::runTasks() {
+  llvm::Error Err;
+  for (const auto &Task : Tasks) {
+    // FIXME: Actually do stuff.
+    (void)Task;
+  }
+  return Err;
+}
+
+} // end namespace refactor
+} // end namespace refactor
Index: clang-refactor/core/CMakeLists.txt
===================================================================
--- /dev/null
+++ clang-refactor/core/CMakeLists.txt
@@ -0,0 +1,16 @@
+add_clang_library(clangRefactorCore
+  RefactoringContext.cpp
+  RefactoringModule.cpp
+  BasicExecutor.cpp
+  ModuleManager.cpp
+  ModuleEntryPoint.cpp
+
+  LINK_LIBS
+  clangAST
+  clangASTMatchers
+  clangBasic
+  clangFrontend
+  clangLex
+  clangTooling
+  clangToolingCore
+  )
Index: clang-refactor/core/Executor.h
===================================================================
--- /dev/null
+++ clang-refactor/core/Executor.h
@@ -0,0 +1,34 @@
+//===--- Executor.h - clang-refactor ----------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_EXECUTOR_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_EXECUTOR_H
+
+#include "RefactoringOptions.h"
+#include "clang/Basic/LLVM.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Error.h"
+#include <string>
+#include <vector>
+
+namespace clang {
+namespace refactor {
+
+class Executor {
+public:
+  virtual void addTask(StringRef TU, const RefactoringOptions &Opts) = 0;
+  virtual llvm::Error runTasks() = 0;
+  virtual ~Executor() = default;
+};
+
+} // end namespace refactor
+} // end namespace refactor
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_EXECUTOR_H
Index: clang-refactor/core/ModuleEntryPoint.h
===================================================================
--- /dev/null
+++ clang-refactor/core/ModuleEntryPoint.h
@@ -0,0 +1,29 @@
+//===--- ModuleEntryPoint.h - clang-refactor --------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_MODULE_ENTRY_POINT_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_MODULE_ENTRY_POINT_H
+
+#include "BasicExecutor.h"
+#include "RefactoringModule.h"
+#include "RefactoringContext.h"
+#include "SymbolIndexClient.h"
+#include "llvm/Support/Error.h"
+
+namespace clang {
+namespace refactor {
+
+class RefactoringModule;
+llvm::Error EntryPoint(std::unique_ptr<RefactoringModule> &Module, int argc,
+                       const char **argv);
+
+} // end namespace refactor
+} // end namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_MODULE_ENTRY_POINT
Index: clang-refactor/core/ModuleEntryPoint.cpp
===================================================================
--- /dev/null
+++ clang-refactor/core/ModuleEntryPoint.cpp
@@ -0,0 +1,38 @@
+//===--- ModuleEntryPoint.cpp - clang-refactor ------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ModuleEntryPoint.h"
+
+namespace clang {
+namespace refactor {
+
+llvm::Error EntryPoint(std::unique_ptr<RefactoringModule> &Module,
+                              int argc, const char **argv) {
+  llvm::Error Err;
+
+  Module->registerOptions();
+
+  // FIXME: Create RefactoringOptions from CLI arguments.
+  RefactoringOptions CommandLineOptions;
+
+  SymbolIndexClient IndexClient;
+  BasicExecutor Exec;
+
+  RefactoringContext Ctx(&IndexClient, &Exec);
+
+  RefactoringOptions PlanExecutionOptions =
+      Module->planExecution(Ctx, CommandLineOptions);
+
+  Exec.runTasks();
+
+  return Err;
+}
+
+} // end namespace refactor
+} // end namespace clang
Index: clang-refactor/core/ModuleManager.h
===================================================================
--- /dev/null
+++ clang-refactor/core/ModuleManager.h
@@ -0,0 +1,46 @@
+//===--- ModuleManager.h - clang-refactor -----------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_MODULE_MANAGER_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_MODULE_MANAGER_H
+
+#include "ModuleEntryPoint.h"
+#include "BasicExecutor.h"
+#include "RefactoringModule.h"
+#include "clang/Basic/LLVM.h"
+#include "llvm/ADT/StringRef.h"
+#include <map>
+#include <string>
+#include <vector>
+
+namespace clang {
+namespace refactor {
+
+class ModuleManager {
+public:
+  void addModule(StringRef Command, std::unique_ptr<RefactoringModule> Module);
+
+  int dispatch(StringRef Command, int argc, const char **argv);
+
+  std::string getTopLevelHelp();
+
+private:
+  const std::string HelpHead = "USAGE: clang-refactor [subcommand] [options] "
+                               "<source0> [... <sourceN>]\n"
+                               "\n"
+                               "Subcommands:\n";
+
+  std::map<std::string, std::unique_ptr<RefactoringModule>>
+      CommandToModule;
+};
+
+} // end namespace refactor
+} // end namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_MODULE_MANAGER_H
Index: clang-refactor/core/ModuleManager.cpp
===================================================================
--- /dev/null
+++ clang-refactor/core/ModuleManager.cpp
@@ -0,0 +1,38 @@
+//===--- ModuleManager.cpp - clang-refactor ---------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ModuleManager.h"
+
+namespace clang {
+namespace refactor {
+
+void ModuleManager::addModule(StringRef Command,
+                              std::unique_ptr<RefactoringModule> Module) {
+  CommandToModule[Command] = std::move(Module);
+}
+
+int ModuleManager::dispatch(StringRef Command, int argc,
+                                    const char **argv) {
+  auto it = CommandToModule.find(Command);
+  if (it != CommandToModule.end()) {
+    EntryPoint(it->second, argc, argv);
+  }
+  return 1;
+}
+
+std::string ModuleManager::getTopLevelHelp() {
+  std::string Result = HelpHead;
+  for (const auto &CommandToModulePair : CommandToModule) {
+    Result += std::string(CommandToModulePair.second->getModuleName());
+  }
+  return Result;
+}
+
+} // end namespace refactor
+} // end namespace clang
Index: clang-refactor/core/RefactoringContext.h
===================================================================
--- /dev/null
+++ clang-refactor/core/RefactoringContext.h
@@ -0,0 +1,43 @@
+//===--- RefactoringContext.h - clang-refactor ------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_REFACTORING_CONTEXT_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_REFACTORING_CONTEXT_H
+
+#include "BasicExecutor.h"
+#include "ModuleEntryPoint.h"
+#include "SymbolIndexClient.h"
+#include "clang/Basic/LLVM.h"
+#include "llvm/ADT/StringRef.h"
+#include <functional>
+#include <map>
+#include <string>
+#include <vector>
+
+namespace clang {
+namespace refactor {
+
+class RefactoringContext {
+public:
+  RefactoringContext(SymbolIndexClient *IndexClient, Executor *Exec);
+
+  void parseAST(/* ... */);
+
+private:
+  SymbolIndexClient *IndexClient;
+  Executor *Exec;
+  // FIXME: What else?
+  //        File?
+  //        ...?
+};
+
+} // end namespace refactor
+} // end namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_REFACTORING_CONTEXT_H
Index: clang-refactor/core/RefactoringContext.cpp
===================================================================
--- /dev/null
+++ clang-refactor/core/RefactoringContext.cpp
@@ -0,0 +1,22 @@
+//===--- RefactoringContext.cpp - clang-refactor ----------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "RefactoringContext.h"
+
+namespace clang {
+namespace refactor {
+
+RefactoringContext::RefactoringContext(SymbolIndexClient *IndexClient,
+                                       Executor *Exec)
+    : IndexClient(IndexClient), Exec(Exec) {}
+
+void RefactoringContext::parseAST(/* ... */) {}
+
+} // end namespace refactor
+} // end namespace clang
Index: clang-refactor/core/RefactoringModule.h
===================================================================
--- /dev/null
+++ clang-refactor/core/RefactoringModule.h
@@ -0,0 +1,98 @@
+//===--- RefactoringModule.h - clang-refactor -------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_REFACTORING_MODULE_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_REFACTORING_MODULE_H
+
+#include "Executor.h"
+#include "RefactoringContext.h"
+#include "RefactoringOptions.h"
+#include "SymbolIndexClient.h"
+#include "clang/Basic/Diagnostic.h"
+#include "clang/Basic/LLVM.h"
+#include "clang/Tooling/CommonOptionsParser.h"
+#include "clang/Tooling/CompilationDatabase.h"
+#include "clang/Tooling/Refactoring.h"
+#include "clang/Tooling/Tooling.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/ErrorOr.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Signals.h"
+#include <string>
+
+namespace clang {
+namespace refactor {
+
+class RefactoringContext;
+
+class RefactoringModule {
+public:
+  RefactoringModule(StringRef ModuleName, StringRef ModuleDescription);
+
+  //===--------------------------------------------------------------------===//
+  // Pre-stage I: register CLI options.
+  //===--------------------------------------------------------------------===//
+  virtual llvm::cl::OptionCategory registerOptions() = 0;
+  //===--------------------------------------------------------------------===//
+
+  //===--------------------------------------------------------------------===//
+  // Stage I: Plan execution.
+  //
+  // FIXME: Describe current stage.
+  //
+  // Input: Options retrieved from command line arguments, ASTContext for
+  // translation unit, to which <source0> belongs to, cross-reference symbol
+  // index, executor.
+  //
+  // Ouput: Submodule-specific information for independent translation unit
+  // processing.
+  //
+  //===--------------------------------------------------------------------===//
+  virtual RefactoringOptions planExecution(const RefactoringContext &Ctx,
+                                           const RefactoringOptions &Opts) = 0;
+  //===--------------------------------------------------------------------===//
+
+  //===--------------------------------------------------------------------===//
+  // Stage II: Running on a single translation unit.
+  //
+  // FIXME: Describe current stage.
+  //
+  // Input: Compiler instance, translation unit main file.
+  //
+  // Output: list of replacements and diagnostics.
+  //
+  // Has access to: AST of given translation unit.
+  //
+  //===--------------------------------------------------------------------===//
+  virtual std::unique_ptr<ASTConsumer>
+  createASTConsumer(CompilerInstance &CI, StringRef InputFile,
+                    const RefactoringOptions &Opts) = 0;
+  //===--------------------------------------------------------------------===//
+
+  StringRef getModuleName();
+  StringRef getModuleDescription();
+
+  virtual ~RefactoringModule();
+
+private:
+  // ModuleName is the lowercase submodule name, which will be passed to
+  // clang-refactor to invoke the submodule tool.
+  const std::string ModuleName;
+
+  // ModuleDescription will appear as the module description upon calling
+  // $ clang-refactor --help
+  const std::string ModuleDescription;
+};
+
+} // end namespace refactor
+} // end namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_REFACTORING_MODULE_H
Index: clang-refactor/core/RefactoringModule.cpp
===================================================================
--- /dev/null
+++ clang-refactor/core/RefactoringModule.cpp
@@ -0,0 +1,28 @@
+//===--- RefactoringModule.cpp - clang-refactor -----------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "RefactoringModule.h"
+
+namespace clang {
+namespace refactor {
+
+RefactoringModule::RefactoringModule(StringRef ModuleName,
+                                     StringRef ModuleDescription)
+    : ModuleName(ModuleName), ModuleDescription(ModuleDescription) {}
+
+StringRef RefactoringModule::getModuleName() { return ModuleName; }
+
+StringRef RefactoringModule::getModuleDescription() {
+  return ModuleDescription;
+}
+
+RefactoringModule::~RefactoringModule() = default;
+
+} // end namespace refactor
+} // end namespace clang
Index: clang-refactor/core/RefactoringOptions.h
===================================================================
--- /dev/null
+++ clang-refactor/core/RefactoringOptions.h
@@ -0,0 +1,25 @@
+//===--- RefactoringOptions.h - clang-refactor ------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_REFACTORING_OPTIONS_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_REFACTORING_OPTIONS_H
+
+#include "llvm/ADT/StringMap.h"
+#include <string>
+
+namespace clang {
+namespace refactor {
+
+// FIXME: Once it's not enough, implement <class RefactoringOptions>.
+typedef llvm::StringMap<std::string> RefactoringOptions;
+
+} // end namespace refactor
+} // end namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_REFACTORING_OPTIONS_H
Index: clang-refactor/core/SymbolIndexClient.h
===================================================================
--- /dev/null
+++ clang-refactor/core/SymbolIndexClient.h
@@ -0,0 +1,33 @@
+//===--- SymbolIndexClient.h - clang-refactor -------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_SYMBOL_INDEX_CLIENT_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_SYMBOL_INDEX_CLIENT_H
+
+#include <vector>
+#include <string>
+
+namespace clang {
+namespace refactor {
+
+// FIXME: Implement two following classes.
+// SymbolDeclaration and SymbolUsage might reuse clang::tooling::Range.
+struct SymbolDeclaration {};
+struct SymbolUsage {};
+
+class SymbolIndexClient {
+public:
+  std::vector<SymbolDeclaration> getDeclarationsForUSR(StringRef USR);
+  std::vector<SymbolUsage> getReferencesForUSR(StringRef USR);
+};
+
+} // end namespace refactor
+} // end namespace refactor
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_REFACTOR_SYMBOL_INDEX_CLIENT_H
Index: clang-refactor/driver/CMakeLists.txt
===================================================================
--- /dev/null
+++ clang-refactor/driver/CMakeLists.txt
@@ -0,0 +1,17 @@
+set(LLVM_LINK_COMPONENTS
+  Support
+  )
+
+add_clang_executable(clang-refactor
+  Driver.cpp
+  )
+
+target_link_libraries(clang-refactor
+  clangAST
+  clangASTMatchers
+  clangBasic
+  clangFrontend
+  clangTooling
+
+  clangRefactorCore
+  )
Index: clang-refactor/driver/Driver.cpp
===================================================================
--- /dev/null
+++ clang-refactor/driver/Driver.cpp
@@ -0,0 +1,48 @@
+//===--- Driver.cpp - clang-refactor ----------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+///  \file This file implements a clang-refactor tool.
+///
+////===----------------------------------------------------------------------===//
+
+#include "clang/Tooling/CommonOptionsParser.h"
+#include "llvm/Support/raw_ostream.h"
+
+#include "ModuleManager.h"
+
+namespace clang {
+namespace refactor {
+
+static int printHelpMessage(ModuleManager &Manager) {
+  llvm::outs() << Manager.getTopLevelHelp();
+  return 1;
+}
+
+int clangRefactorMain(int argc, const char **argv) {
+  ModuleManager Manager;
+  if (argc > 1) {
+    llvm::StringRef FirstArgument(argv[1]);
+    if (FirstArgument == "-h" || FirstArgument == "-help" ||
+        FirstArgument == "--help")
+      return printHelpMessage(Manager);
+    const std::string Command = argv[1];
+    argv[1] = (llvm::Twine(argv[0]) + " " + llvm::Twine(argv[1])).str().c_str();
+    Manager.dispatch(Command, argc - 1, argv + 1);
+  } else {
+    return printHelpMessage(Manager);
+  }
+  return 0;
+}
+
+} // end namespace refactor
+} // end namespace clang
+
+int main(int argc, const char **argv) {
+  return clang::refactor::clangRefactorMain(argc, argv);
+}