cpp11-migrate: Refactor for driver model of operation

Re-commit of r189691 and r189689 now with a proper autoconf fix.

Massive simplification of how replacements and file overrides are
handled by the migrator:
* Sources and headers are all treated the same.
* All replacements for a given translation unit are stored in the same
  TranslationUnitReplacements structure.
* Change tracking is updated only from main file; no need for
  propagating "is tracking" flag around.
* Transform base class no longer responsible for applying replacements.
  They are simply stored and main() looks after deduplication and
  application.
* Renamed -yaml-only to -serialize-replacements. Same restrictions apply:
  Can only request one transform. New restriction: formatting cannot also
  be turned on since it's basically a transform.
* If -serialize-replacements is requested, changes to files will not be
  applied on disk.
* Changed behaviour of function generating names for serialized
  replacements: Only the main source file goes into the name of the file
  since a file may contain changes for multiple different files.
* Updated HeaderReplacements LIT test for new serialization behaviour.
  * Replaced old test that ensures replacements are not serialized if
    -serialize-replacements is not provided. New version ensures changes
    are made directly to all files in the translation unit.
* Updated unit tests.
  * Due to major simplification of structures in FileOverrides.h, the
    FileOverridesTest is quite a bit simpler now.

llvm-svn: 189798

9 files changed, 215 insertions, 396 deletions

diff --git a/clang-tools-extra/cpp11-migrate/Core/FileOverrides.cpp b/clang-tools-extra/cpp11-migrate/Core/FileOverrides.cpp
index d8d4b3f27e1..7ab7e91c30c 100644
--- a/clang-tools-extra/cpp11-migrate/Core/FileOverrides.cpp
+++ b/clang-tools-extra/cpp11-migrate/Core/FileOverrides.cpp
@@ -29,157 +29,14 @@
 using namespace clang;
 using namespace clang::tooling;
 
-void HeaderOverride::recordReplacements(
-    const clang::tooling::Replacements &Replaces) {
-  Replacements.Replacements.resize(Replaces.size());
-  std::copy(Replaces.begin(), Replaces.end(),
-            Replacements.Replacements.begin());
-}
-
-SourceOverrides::SourceOverrides(llvm::StringRef MainFileName,
-                                 bool TrackChanges)
-    : MainFileName(MainFileName), TrackChanges(TrackChanges) {}
-
-void
-SourceOverrides::applyReplacements(clang::tooling::Replacements &Replaces) {
-  llvm::IntrusiveRefCntPtr<clang::DiagnosticOptions> DiagOpts(
-      new DiagnosticOptions());
-  DiagnosticsEngine Diagnostics(
-      llvm::IntrusiveRefCntPtr<DiagnosticIDs>(new DiagnosticIDs()),
-      DiagOpts.getPtr());
-  FileManager Files((FileSystemOptions()));
-  SourceManager SM(Diagnostics, Files);
-  applyReplacements(Replaces, SM);
-}
-
-void SourceOverrides::applyReplacements(clang::tooling::Replacements &Replaces,
-                                        clang::SourceManager &SM) {
-  applyOverrides(SM);
-
-  Rewriter Rewrites(SM, LangOptions());
-
-  // FIXME: applyAllReplacements will indicate if it couldn't apply all
-  // replacements. Handle that case.
-  bool Success = tooling::applyAllReplacements(Replaces, Rewrites);
-
-  if (!Success)
-    llvm::errs() << "error: failed to apply some replacements.";
-
-  std::string ResultBuf;
-
-  for (Rewriter::buffer_iterator I = Rewrites.buffer_begin(),
-                                 E = Rewrites.buffer_end();
-       I != E; ++I) {
-    const FileEntry *Entry =
-        Rewrites.getSourceMgr().getFileEntryForID(I->first);
-    assert(Entry != NULL && "unexpected null FileEntry");
-    assert(Entry->getName() != NULL &&
-           "unexpected null return from FileEntry::getName()");
-    llvm::StringRef FileName = Entry->getName();
-
-    // Get a copy of the rewritten buffer from the Rewriter.
-    ResultBuf.clear();
-    llvm::raw_string_ostream StringStream(ResultBuf);
-    I->second.write(StringStream);
-    StringStream.flush();
-
-    if (MainFileName == FileName) {
-      MainFileOverride.swap(ResultBuf);
-      continue;
-    }
-
-    // Header overrides are treated differently. Eventually, raw replacements
-    // will be stored as well for later output to disk. Applying replacements
-    // in memory will always be necessary as the source goes down the transform
-    // pipeline.
-    HeaderOverride &HeaderOv = Headers[FileName];
-    // "Create" HeaderOverride if not already existing
-    if (HeaderOv.getHeaderPath().empty())
-      HeaderOv = HeaderOverride(FileName, MainFileName);
-
-    HeaderOv.swapContentOverride(ResultBuf);
-  }
-
-  // Separate replacements to header files
-  Replacements MainFileReplaces;
-  ReplacementsMap HeadersReplaces;
-  for (Replacements::const_iterator I = Replaces.begin(), E = Replaces.end();
-      I != E; ++I) {
-    llvm::StringRef ReplacementFileName = I->getFilePath();
-
-    if (ReplacementFileName == MainFileName) {
-      MainFileReplaces.insert(*I);
-      continue;
-    }
-
-    HeadersReplaces[ReplacementFileName].insert(*I);
-  }
-
-  // Record all replacements to headers.
-  for (ReplacementsMap::const_iterator I = HeadersReplaces.begin(),
-                                       E = HeadersReplaces.end();
-       I != E; ++I) {
-    HeaderOverride &HeaderOv = Headers[I->getKey()];
-    HeaderOv.recordReplacements(I->getValue());
-  }
-
-  if (TrackChanges)
-    adjustChangedRanges(MainFileReplaces, HeadersReplaces);
-}
-
-void
-SourceOverrides::adjustChangedRanges(const Replacements &MainFileReplaces,
-                                     const ReplacementsMap &HeadersReplaces) {
-  // Adjust the changed ranges for each individual file
-  MainFileChanges.adjustChangedRanges(MainFileReplaces);
-  for (ReplacementsMap::const_iterator I = HeadersReplaces.begin(),
-                                       E = HeadersReplaces.end();
-       I != E; ++I) {
-    Headers[I->getKey()].adjustChangedRanges(I->getValue());
-  }
-}
-
-void SourceOverrides::applyOverrides(SourceManager &SM) const {
-  FileManager &FM = SM.getFileManager();
-
-  if (isSourceOverriden())
-    SM.overrideFileContents(FM.getFile(MainFileName),
-                            llvm::MemoryBuffer::getMemBuffer(MainFileOverride));
-
-  for (HeaderOverrides::const_iterator I = Headers.begin(), E = Headers.end();
-       I != E; ++I) {
-    assert(!I->second.getContentOverride().empty() &&
-           "Header override should not be empty!");
-    SM.overrideFileContents(
-        FM.getFile(I->second.getHeaderPath()),
-        llvm::MemoryBuffer::getMemBuffer(I->second.getContentOverride()));
-  }
-}
-
-bool generateReplacementsFileName(llvm::StringRef SourceFile,
-                                    llvm::StringRef HeaderFile,
-                                    llvm::SmallVectorImpl<char> &Result,
-                                    llvm::SmallVectorImpl<char> &Error) {
+bool generateReplacementsFileName(const llvm::StringRef MainSourceFile,
+                                  llvm::SmallVectorImpl<char> &Result,
+                                  llvm::SmallVectorImpl<char> &Error) {
   using namespace llvm::sys;
-  std::string UniqueHeaderNameModel;
-
-  // Get the filename portion of the path.
-  llvm::StringRef SourceFileRef(path::filename(SourceFile));
-  llvm::StringRef HeaderFileRef(path::filename(HeaderFile));
-
-  // Get the actual path for the header file.
-  llvm::SmallString<128> HeaderPath(HeaderFile);
-  path::remove_filename(HeaderPath);
-
-  // Build the model of the filename.
-  llvm::raw_string_ostream UniqueHeaderNameStream(UniqueHeaderNameModel);
-  UniqueHeaderNameStream << SourceFileRef << "_" << HeaderFileRef
-                         << "_%%_%%_%%_%%_%%_%%" << ".yaml";
-  path::append(HeaderPath, UniqueHeaderNameStream.str());
 
   Error.clear();
-  if (llvm::error_code EC =
-          fs::createUniqueFile(HeaderPath.c_str(), Result)) {
+  if (llvm::error_code EC = fs::createUniqueFile(
+          MainSourceFile + "_%%_%%_%%_%%_%%_%%.yaml", Result)) {
     Error.append(EC.message().begin(), EC.message().end());
     return false;
   }
@@ -187,20 +44,6 @@ bool generateReplacementsFileName(llvm::StringRef SourceFile,
   return true;
 }
 
-FileOverrides::~FileOverrides() {
-  for (SourceOverridesMap::iterator I = Overrides.begin(), E = Overrides.end();
-       I != E; ++I)
-    delete I->getValue();
-}
-
-SourceOverrides &FileOverrides::getOrCreate(llvm::StringRef Filename) {
-  SourceOverrides *&Override = Overrides[Filename];
-
-  if (Override == NULL)
-    Override = new SourceOverrides(Filename, TrackChanges);
-  return *Override;
-}
-
 namespace {
 
 /// \brief Comparator to be able to order tooling::Range based on their offset.
@@ -247,10 +90,11 @@ struct RangeReplacedAdjuster {
 
 } // end anonymous namespace
 
-void ChangedRanges::adjustChangedRanges(const tooling::Replacements &Replaces) {
+void
+ChangedRanges::adjustChangedRanges(const tooling::ReplacementsVec &Replaces) {
   // first adjust existing ranges in case they overlap with the replacements
-  for (Replacements::iterator I = Replaces.begin(), E = Replaces.end(); I != E;
-       ++I) {
+  for (ReplacementsVec::const_iterator I = Replaces.begin(), E = Replaces.end();
+       I != E; ++I) {
     const tooling::Replacement &Replace = *I;
 
     std::transform(Ranges.begin(), Ranges.end(), Ranges.begin(),
@@ -265,8 +109,8 @@ void ChangedRanges::adjustChangedRanges(const tooling::Replacements &Replaces) {
   }
 
   // then generate the new ranges from the replacements
-  for (Replacements::iterator I = Replaces.begin(), E = Replaces.end(); I != E;
-       ++I) {
+  for (ReplacementsVec::const_iterator I = Replaces.begin(), E = Replaces.end();
+       I != E; ++I) {
     const tooling::Replacement &R = *I;
     unsigned Offset = tooling::shiftedCodePosition(Replaces, R.getOffset());
     unsigned Length = R.getReplacementText().size();
@@ -303,3 +147,52 @@ void ChangedRanges::coalesceRanges() {
                            std::mem_fun_ref(&Range::contains)),
                Ranges.end());
 }
+
+void FileOverrides::applyOverrides(clang::SourceManager &SM) const {
+  FileManager &FM = SM.getFileManager();
+
+  for (FileStateMap::const_iterator I = FileStates.begin(),
+                                    E = FileStates.end();
+       I != E; ++I) {
+    SM.overrideFileContents(FM.getFile(I->getKey()),
+                            llvm::MemoryBuffer::getMemBuffer(I->getValue()));
+  }
+}
+
+void FileOverrides::adjustChangedRanges(
+    const clang::replace::FileToReplacementsMap &Replaces) {
+
+  for (replace::FileToReplacementsMap::const_iterator I = Replaces.begin(),
+       E = Replaces.end(); I != E; ++I) {
+    ChangeTracking[I->getKey()].adjustChangedRanges(I->getValue());
+  }
+}
+
+void FileOverrides::updateState(const clang::Rewriter &Rewrites) {
+  for (Rewriter::const_buffer_iterator BufferI = Rewrites.buffer_begin(),
+                                       BufferE = Rewrites.buffer_end();
+       BufferI != BufferE; ++BufferI) {
+    const char *FileName =
+        Rewrites.getSourceMgr().getFileEntryForID(BufferI->first)->getName();
+    const RewriteBuffer &RewriteBuf = BufferI->second;
+    FileStates[FileName].assign(RewriteBuf.begin(), RewriteBuf.end());
+  }
+}
+
+bool FileOverrides::writeToDisk(DiagnosticsEngine &Diagnostics) const {
+  bool Errors = false;
+  for (FileStateMap::const_iterator I = FileStates.begin(),
+                                    E = FileStates.end();
+       I != E; ++I) {
+    std::string ErrorInfo;
+    // The extra transform through std::string is to ensure null-termination
+    // of the filename stored as the key of the StringMap.
+    llvm::raw_fd_ostream FileStream(I->getKey().str().c_str(), ErrorInfo);
+    if (!ErrorInfo.empty()) {
+      llvm::errs() << "Failed to write new state for " << I->getKey() << ".\n";
+      Errors = true;
+    }
+    FileStream << I->getValue();
+  }
+  return !Errors;
+}
diff --git a/clang-tools-extra/cpp11-migrate/Core/FileOverrides.h b/clang-tools-extra/cpp11-migrate/Core/FileOverrides.h
index 3e81abc6d34..8cde7591303 100644
--- a/clang-tools-extra/cpp11-migrate/Core/FileOverrides.h
+++ b/clang-tools-extra/cpp11-migrate/Core/FileOverrides.h
@@ -16,7 +16,8 @@
 #ifndef CPP11_MIGRATE_FILE_OVERRIDES_H
 #define CPP11_MIGRATE_FILE_OVERRIDES_H
 
-#include "clang/Tooling/Refactoring.h"
+#include "Core/Refactoring.h"
+#include "clang-replace/Tooling/ApplyReplacements.h"
 #include "clang/Tooling/ReplacementsYaml.h"
 #include "llvm/ADT/StringMap.h"
 
@@ -44,13 +45,13 @@ public:
   /// to remove replaced parts.
   ///
   /// Note that all replacements should come from the same file.
-  void adjustChangedRanges(const clang::tooling::Replacements &Replaces);
+  void adjustChangedRanges(const clang::tooling::ReplacementsVec &Replaces);
 
   /// \brief Iterators.
-  /// @{
+  /// \{
   const_iterator begin() const { return Ranges.begin(); }
   const_iterator end() const { return Ranges.end(); }
-  /// @}
+  /// \}
 
 private:
   void coalesceRanges();
@@ -58,178 +59,71 @@ private:
   RangeVec Ranges;
 };
 
-/// \brief Container for storing override information for a single headers.
-class HeaderOverride {
+/// \brief Maintains current state of transformed files and tracks source ranges
+/// where changes have been made.
+class FileOverrides {
 public:
-  /// \brief Constructors.
-  /// @{
-  HeaderOverride() {}
-  HeaderOverride(llvm::StringRef HeaderPath,
-                 llvm::StringRef MainSourceFile) : HeaderPath(HeaderPath) {
-    Replacements.MainSourceFile = MainSourceFile;
-  }
-  /// @}
-
-  /// \brief Getter for HeaderPath.
-  llvm::StringRef getHeaderPath() const {
-    return HeaderPath;
-  }
+  /// \brief Maps file names to file contents.
+  typedef llvm::StringMap<std::string> FileStateMap;
 
-  /// \brief Accessor for ContentOverride.
-  /// @{
-  llvm::StringRef getContentOverride() const { return ContentOverride; }
-  void setContentOverride(const llvm::StringRef S) { ContentOverride = S; }
-  /// @}
+  /// \brief Maps file names to change tracking info for a file.
+  typedef llvm::StringMap<ChangedRanges> ChangeMap;
 
-  /// \brief Getter for Changes.
-  const ChangedRanges &getChanges() const { return Changes; }
 
-  /// \brief Swaps the content of ContentOverride with \p S.
-  void swapContentOverride(std::string &S) { ContentOverride.swap(S); }
-
-  /// \brief Getter for Replacements.
-  const clang::tooling::TranslationUnitReplacements &getReplacements() const {
-    return Replacements;
-  }
+  /// \brief Override file contents seen by \c SM for all files stored by this
+  /// object.
+  void applyOverrides(clang::SourceManager &SM) const;
 
-  /// \brief Stores the replacements made by a transform to the header this
-  /// object represents.
-  void recordReplacements(const clang::tooling::Replacements &Replaces);
+  /// \brief Update change tracking information based on replacements stored in
+  /// \c Replaces.
+  void
+  adjustChangedRanges(const clang::replace::FileToReplacementsMap &Replaces);
 
-  /// \brief Helper function to adjust the changed ranges.
-  void adjustChangedRanges(const clang::tooling::Replacements &Replaces) {
-    Changes.adjustChangedRanges(Replaces);
+  /// \brief Accessor for change tracking information.
+  const ChangeMap &getChangedRanges() const {
+    return ChangeTracking;
   }
 
-private:
-  std::string ContentOverride;
-  ChangedRanges Changes;
-  std::string HeaderPath;
-  clang::tooling::TranslationUnitReplacements Replacements;
-};
-
-/// \brief Container mapping header file names to override information.
-typedef llvm::StringMap<HeaderOverride> HeaderOverrides;
-
-/// \brief Container storing the file content overrides for a source file and
-/// any headers included by the source file either directly or indirectly to
-/// which changes have been made.
-class SourceOverrides {
-public:
-  SourceOverrides(llvm::StringRef MainFileName, bool TrackChanges);
-
-  /// \brief Accessors.
-  /// @{
-  llvm::StringRef getMainFileName() const { return MainFileName; }
-  llvm::StringRef getMainFileContent() const { return MainFileOverride; }
-  const ChangedRanges &getChangedRanges() const { return MainFileChanges; }
-
-  /// \brief Is file change tracking enabled?
+  /// \brief Coalesce changes stored in \c Rewrites and replace file contents 
+  /// overrides stored in this object.
   ///
-  /// Tracking file changes can be useful to reformat the code for example.
-  bool isTrackingFileChanges() const { return TrackChanges; }
-  /// @}
+  /// \param Rewrites Rewriter containing changes to files.
+  void updateState(const clang::Rewriter &Rewrites);
 
-  /// \brief Indicates if the source file has been overridden.
-  ///
-  /// It's possible for a source to remain unchanged while only headers are
-  /// changed.
-  bool isSourceOverriden() const { return !MainFileOverride.empty(); }
+  /// \brief Accessor for current file state.
+  const FileStateMap &getState() const { return FileStates; }
 
-  /// \brief Override the file contents by applying all the replacements.
+  /// \brief Write all file contents overrides to disk.
   ///
-  /// \param Replaces The replacements to apply.
-  /// \param SM A user provided SourceManager to be used when applying rewrites.
-  void applyReplacements(clang::tooling::Replacements &Replaces,
-                         clang::SourceManager &SM);
-  void applyReplacements(clang::tooling::Replacements &Replaces);
-
-  /// \brief Convenience function for applying this source's overrides to
-  /// the given SourceManager.
-  void applyOverrides(clang::SourceManager &SM) const;
-
-  /// \brief Iterators.
-  /// @{
-  HeaderOverrides::iterator headers_begin() { return Headers.begin(); }
-  HeaderOverrides::iterator headers_end() { return Headers.end(); }
-  HeaderOverrides::const_iterator headers_begin() const {
-    return Headers.begin();
-  }
-  HeaderOverrides::const_iterator headers_end() const { return Headers.end(); }
-  /// @}
-
-private:
-  typedef llvm::StringMap<clang::tooling::Replacements> ReplacementsMap;
-
-  /// \brief Flatten the Rewriter buffers of \p Rewrite and store results as
-  /// file content overrides.
-  void applyRewrites(clang::Rewriter &Rewrite);
-
-  /// \brief Adjust the changed ranges to reflect the parts of the files that
-  /// have been replaced.
-  void adjustChangedRanges(const clang::tooling::Replacements &Replaces,
-                           const ReplacementsMap &HeadersReplaces);
-
-  const std::string MainFileName;
-  std::string MainFileOverride;
-  const bool TrackChanges;
-  ChangedRanges MainFileChanges;
-  HeaderOverrides Headers;
-};
-
-/// \brief Maps source file names to content override information.
-class FileOverrides {
-public:
-  typedef llvm::StringMap<SourceOverrides *> SourceOverridesMap;
-  typedef SourceOverridesMap::const_iterator const_iterator;
-
-  /// \brief Construct the SourceOverrides manager.
+  /// \param Diagnostics DiagnosticsEngine for error output.
   ///
-  /// \param TrackChanges Wether or not the \c SourceOverrides should keep track
-  /// of changes. See \c SourceOverrides::isTrackingFileChanges().
-  FileOverrides(bool TrackChanges) : TrackChanges(TrackChanges) {}
-  ~FileOverrides();
-
-  const_iterator find(llvm::StringRef Filename) const {
-    return Overrides.find(Filename);
-  }
-
-  /// \brief Get the \c SourceOverrides for \p Filename, creating it if
-  /// necessary.
-  SourceOverrides &getOrCreate(llvm::StringRef Filename);
-
-  /// \brief Iterators.
-  /// @{
-  const_iterator begin() const { return Overrides.begin(); }
-  const_iterator end() const { return Overrides.end(); }
-  /// @}
+  /// \returns \li true if all files with overridden file contents were written
+  ///              to disk successfully.
+  ///          \li false if any failure occurred.
+  bool writeToDisk(clang::DiagnosticsEngine &Diagnostics) const;
 
 private:
-  FileOverrides(const FileOverrides &) LLVM_DELETED_FUNCTION;
-  FileOverrides &operator=(const FileOverrides &) LLVM_DELETED_FUNCTION;
-
-  SourceOverridesMap Overrides;
-  const bool TrackChanges;
+  FileStateMap FileStates;
+  ChangeMap ChangeTracking;
 };
 
 /// \brief Generate a unique filename to store the replacements.
 ///
-/// Generates a unique filename in the same directory as the header file. The
-/// filename is based on the following model:
+/// Generates a unique filename in the same directory as \c MainSourceFile. The
+/// filename is generated following this pattern:
 ///
-/// source.cpp_header.h_%%_%%_%%_%%_%%_%%.yaml
+/// MainSourceFile_%%_%%_%%_%%_%%_%%.yaml
 ///
 /// where all '%' will be replaced by a randomly chosen hex number.
 ///
-/// @param SourceFile Full path to the source file.
-/// @param HeaderFile Full path to the header file.
-/// @param Result The resulting unique filename in the same directory as the
-///        header file.
-/// @param Error Description of the error if there is any.
-/// @returns true if succeeded, false otherwise.
-bool generateReplacementsFileName(llvm::StringRef SourceFile,
-                                    llvm::StringRef HeaderFile,
-                                    llvm::SmallVectorImpl<char> &Result,
-                                    llvm::SmallVectorImpl<char> &Error);
+/// \param[in] MainSourceFile Full path to the source file.
+/// \param[out] Result The resulting unique filename in the same directory as
+///             the \c MainSourceFile.
+/// \param[out] Error If an error occurs a description of that error is
+///             placed in this string.
+/// \returns true on success, false if a unique file name could not be created.
+bool generateReplacementsFileName(const llvm::StringRef MainSourceFile,
+                                  llvm::SmallVectorImpl<char> &Result,
+                                  llvm::SmallVectorImpl<char> &Error);
 
 #endif // CPP11_MIGRATE_FILE_OVERRIDES_H
diff --git a/clang-tools-extra/cpp11-migrate/Core/Makefile b/clang-tools-extra/cpp11-migrate/Core/Makefile
index 5da4cec8481..51bc98defee 100644
--- a/clang-tools-extra/cpp11-migrate/Core/Makefile
+++ b/clang-tools-extra/cpp11-migrate/Core/Makefile
@@ -11,4 +11,4 @@ LIBRARYNAME := migrateCore
 
 include $(CLANG_LEVEL)/Makefile
 
-CPP.Flags += -I$(PROJ_SRC_DIR)/..
+CPP.Flags += -I$(PROJ_SRC_DIR)/.. -I$(PROJ_SRC_DIR)/../../clang-replace/include
diff --git a/clang-tools-extra/cpp11-migrate/Core/Refactoring.h b/clang-tools-extra/cpp11-migrate/Core/Refactoring.h
new file mode 100644
index 00000000000..a15634a3704
--- /dev/null
+++ b/clang-tools-extra/cpp11-migrate/Core/Refactoring.h
@@ -0,0 +1,31 @@
+//===-- Core/Refactoring.h - Stand-in for Tooling/Refactoring.h -*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief This file is meant to be used instead of clang/Tooling/Refactoring.h
+/// until such time as clang::tooling::Replacements is re-implemented as a
+/// vector instead of a set.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef CPP11_MIGRATE_REPLACEMENTS_VEC_H
+#define CPP11_MIGRATE_REPLACEMENTS_VEC_H
+
+#include "clang/Tooling/Refactoring.h"
+
+// FIXME: Remove this file when clang::tooling::Replacements becomes a vector
+// instead of a set.
+
+namespace clang {
+namespace tooling {
+typedef std::vector<clang::tooling::Replacement> ReplacementsVec;
+}
+}
+
+#endif // CPP11_MIGRATE_REPLACEMENTS_VEC_H
diff --git a/clang-tools-extra/cpp11-migrate/Core/Reformatting.cpp b/clang-tools-extra/cpp11-migrate/Core/Reformatting.cpp
index 4e14ea5784e..50ba1f19f7a 100644
--- a/clang-tools-extra/cpp11-migrate/Core/Reformatting.cpp
+++ b/clang-tools-extra/cpp11-migrate/Core/Reformatting.cpp
@@ -22,39 +22,23 @@
 
 using namespace clang;
 
-void Reformatter::reformatChanges(SourceOverrides &Overrides) {
-  llvm::IntrusiveRefCntPtr<clang::DiagnosticOptions> DiagOpts(
-      new DiagnosticOptions());
-  DiagnosticsEngine Diagnostics(
-      llvm::IntrusiveRefCntPtr<DiagnosticIDs>(new DiagnosticIDs()),
-      DiagOpts.getPtr());
-  FileManager Files((FileSystemOptions()));
-  SourceManager SM(Diagnostics, Files);
-
-  reformatChanges(Overrides, SM);
-}
-
-void Reformatter::reformatChanges(SourceOverrides &Overrides,
-                                  clang::SourceManager &SM) {
-  tooling::Replacements Replaces;
-  Overrides.applyOverrides(SM);
-  if (Overrides.isSourceOverriden())
-    Replaces = reformatSingleFile(Overrides.getMainFileName(),
-                                  Overrides.getChangedRanges(), SM);
-
-  for (HeaderOverrides::const_iterator I = Overrides.headers_begin(),
-                                       E = Overrides.headers_end();
+void Reformatter::reformatChanges(const FileOverrides &FileStates,
+                                  clang::SourceManager &SM,
+                                  clang::tooling::ReplacementsVec &Replaces) {
+  FileStates.applyOverrides(SM);
+
+  for (FileOverrides::ChangeMap::const_iterator
+           I = FileStates.getChangedRanges().begin(),
+           E = FileStates.getChangedRanges().end();
        I != E; ++I) {
-    const HeaderOverride &Header = I->getValue();
-    const tooling::Replacements &HeaderReplaces =
-        reformatSingleFile(Header.getHeaderPath(), Header.getChanges(), SM);
-    Replaces.insert(HeaderReplaces.begin(), HeaderReplaces.end());
+    reformatSingleFile(I->getKey(), I->getValue(), SM, Replaces);
   }
-  Overrides.applyReplacements(Replaces, SM);
 }
 
-tooling::Replacements Reformatter::reformatSingleFile(
-    llvm::StringRef FileName, const ChangedRanges &Changes, SourceManager &SM) {
+void Reformatter::reformatSingleFile(
+    const llvm::StringRef FileName, const ChangedRanges &Changes,
+    SourceManager &SM, clang::tooling::ReplacementsVec &FormatReplacements) {
+
   const clang::FileEntry *Entry = SM.getFileManager().getFile(FileName);
   assert(Entry && "expected an existing file");
 
@@ -72,5 +56,7 @@ tooling::Replacements Reformatter::reformatSingleFile(
   }
 
   Lexer Lex(ID, SM.getBuffer(ID), SM, getFormattingLangOpts(Style.Standard));
-  return format::reformat(Style, Lex, SM, ReformatRanges);
+  const tooling::Replacements &R =
+      format::reformat(Style, Lex, SM, ReformatRanges);
+  std::copy(R.begin(), R.end(), std::back_inserter(FormatReplacements));
 }
diff --git a/clang-tools-extra/cpp11-migrate/Core/Reformatting.h b/clang-tools-extra/cpp11-migrate/Core/Reformatting.h
index e63e51d2160..9a10171a742 100644
--- a/clang-tools-extra/cpp11-migrate/Core/Reformatting.h
+++ b/clang-tools-extra/cpp11-migrate/Core/Reformatting.h
@@ -16,9 +16,10 @@
 #ifndef CPP11_MIGRATE_REFORMATTING_H
 #define CPP11_MIGRATE_REFORMATTING_H
 
+#include "Core/Refactoring.h"
 #include "clang/Format/Format.h"
 
-class SourceOverrides;
+class FileOverrides;
 class ChangedRanges;
 
 class Reformatter {
@@ -27,31 +28,30 @@ public:
 
   /// \brief Reformat the changes made to the file overrides.
   ///
-  /// \param Overrides Overriden source files to reformat. Note that since only
-  /// the changes are reformatted, file change tracking has to be enabled.
-  /// \param SM A SourceManager where the overridens files can be found.
+  /// This function will apply the state of files stored in \c FileState to \c
+  /// SM.
   ///
-  /// \sa \c SourceOverrides::isTrackingFileChanges()
-  void reformatChanges(SourceOverrides &Overrides, clang::SourceManager &SM);
-
-  /// \brief Overload of \c reformatChanges() providing it's own
-  /// \c SourceManager.
-  void reformatChanges(SourceOverrides &Overrides);
+  /// \param[in] FileState Files to reformat.
+  /// \param[in] SM SourceManager for access to source files.
+  /// \param[out] Replaces Container to store all reformatting replacements.
+  void reformatChanges(const FileOverrides &FileState, clang::SourceManager &SM,
+                       clang::tooling::ReplacementsVec &Replaces);
 
   /// \brief Produce a list of replacements to apply on \p FileName, only the
   /// ranges in \p Changes are replaced.
   ///
-  /// Since this routine use \c clang::format::reformat() the rules that applies
-  /// on the ranges are identical:
+  /// Since this routine use \c clang::format::reformat() the rules that
+  /// function applies to ranges also apply here.
   ///
-  /// \par
-  /// Each range is extended on either end to its next bigger logic
-  /// unit, i.e. everything that might influence its formatting or might be
-  /// influenced by its formatting.
-  /// -- \c clang::format::reformat()
-  clang::tooling::Replacements reformatSingleFile(llvm::StringRef FileName,
-                                                  const ChangedRanges &Changes,
-                                                  clang::SourceManager &SM);
+  /// \param[in] FileName Name of file to reformat.
+  /// \param[in] Changes Description of where changes were made to the file.
+  /// \param[in] SM SourceManager required to create replacements.
+  /// \param[out] FormatReplacements New reformatting replacements are appended
+  /// to this container.
+  void reformatSingleFile(const llvm::StringRef FileName,
+                          const ChangedRanges &Changes,
+                          clang::SourceManager &SM,
+                          clang::tooling::ReplacementsVec &FormatReplacements);
 
 private:
   clang::format::FormatStyle Style;
diff --git a/clang-tools-extra/cpp11-migrate/Core/SyntaxCheck.cpp b/clang-tools-extra/cpp11-migrate/Core/SyntaxCheck.cpp
index 7315768f360..bd2eb63044f 100644
--- a/clang-tools-extra/cpp11-migrate/Core/SyntaxCheck.cpp
+++ b/clang-tools-extra/cpp11-migrate/Core/SyntaxCheck.cpp
@@ -30,9 +30,7 @@ public:
     if (!SyntaxOnlyAction::BeginSourceFileAction(CI, Filename))
       return false;
 
-    FileOverrides::const_iterator I = Overrides.find(Filename);
-    if (I != Overrides.end())
-      I->second->applyOverrides(CI.getSourceManager());
+    Overrides.applyOverrides(CI.getSourceManager());
 
     return true;
   }
diff --git a/clang-tools-extra/cpp11-migrate/Core/Transform.cpp b/clang-tools-extra/cpp11-migrate/Core/Transform.cpp
index 4354df2987e..cd76723d316 100644
--- a/clang-tools-extra/cpp11-migrate/Core/Transform.cpp
+++ b/clang-tools-extra/cpp11-migrate/Core/Transform.cpp
@@ -100,13 +100,8 @@ bool Transform::isFileModifiable(const SourceManager &SM,
 bool Transform::handleBeginSource(CompilerInstance &CI, StringRef Filename) {
   assert(Overrides != 0 && "Subclass transform didn't provide InputState");
 
-  CurrentSource = Filename.str();
-
-  FileOverrides::const_iterator I = Overrides->find(CurrentSource);
-  if (I != Overrides->end())
-    I->second->applyOverrides(CI.getSourceManager());
-
-  Replace.clear();
+  Overrides->applyOverrides(CI.getSourceManager());
+  CurrentSource = Filename;
 
   if (Options().EnableTiming) {
     Timings.push_back(std::make_pair(Filename.str(), llvm::TimeRecord()));
@@ -116,11 +111,7 @@ bool Transform::handleBeginSource(CompilerInstance &CI, StringRef Filename) {
 }
 
 void Transform::handleEndSource() {
-  if (!getReplacements().empty()) {
-    SourceOverrides &SO = Overrides->getOrCreate(CurrentSource);
-    SO.applyReplacements(getReplacements());
-  }
-
+  CurrentSource.clear();
   if (Options().EnableTiming)
     Timings.back().second += llvm::TimeRecord::getCurrentTime(false);
 }
@@ -129,6 +120,19 @@ void Transform::addTiming(llvm::StringRef Label, llvm::TimeRecord Duration) {
   Timings.push_back(std::make_pair(Label.str(), Duration));
 }
 
+bool
+Transform::addReplacementForCurrentTU(const clang::tooling::Replacement &R) {
+  if (CurrentSource.empty())
+    return false;
+
+  TranslationUnitReplacements &TU = Replacements[CurrentSource];
+  if (TU.MainSourceFile.empty())
+    TU.MainSourceFile = CurrentSource;
+  TU.Replacements.push_back(R);
+
+  return true;
+}
+
 FrontendActionFactory *Transform::createActionFactory(MatchFinder &Finder) {
   return new ActionFactory(Finder, /*Owner=*/ *this);
 }
diff --git a/clang-tools-extra/cpp11-migrate/Core/Transform.h b/clang-tools-extra/cpp11-migrate/Core/Transform.h
index 43082111d54..45e470d64e4 100644
--- a/clang-tools-extra/cpp11-migrate/Core/Transform.h
+++ b/clang-tools-extra/cpp11-migrate/Core/Transform.h
@@ -17,7 +17,7 @@
 #define CPP11_MIGRATE_TRANSFORM_H
 
 #include "Core/IncludeExcludeInfo.h"
-#include "clang/Tooling/Refactoring.h"
+#include "Core/Refactoring.h"
 #include "llvm/ADT/OwningPtr.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Registry.h"
@@ -52,6 +52,12 @@ class MatchFinder;
 
 class FileOverrides;
 
+
+// \brief Maps main source file names to a TranslationUnitReplacements
+// structure storing replacements for that translation unit.
+typedef llvm::StringMap<clang::tooling::TranslationUnitReplacements>
+TUReplacementsMap;
+
 /// \brief To group transforms' options together when printing the help.
 extern llvm::cl::OptionCategory TransformsOptionsCategory;
 
@@ -99,7 +105,7 @@ public:
   /// SourcePaths and should take precedence over content of files on disk.
   /// Upon return, \p ResultStates shall contain the result of performing this
   /// transform on the files listed in \p SourcePaths.
-  virtual int apply(FileOverrides &InputStates,
+  virtual int apply(const FileOverrides &InputStates,
                     const clang::tooling::CompilationDatabase &Database,
                     const std::vector<std::string> &SourcePaths) = 0;
 
@@ -172,6 +178,17 @@ public:
   /// \brief Return an iterator to the start of collected timing data.
   TimingVec::const_iterator timing_end() const { return Timings.end(); }
 
+  /// \brief Add a Replacement to the list for the current translation unit.
+  ///
+  /// \returns \li true on success
+  ///          \li false if there is no current translation unit
+  bool addReplacementForCurrentTU(const clang::tooling::Replacement &R);
+
+  /// \brief Accessor to Replacements across all transformed translation units.
+  const TUReplacementsMap &getAllReplacements() const {
+    return Replacements;
+  }
+
 protected:
 
   void setAcceptedChanges(unsigned Changes) {
@@ -195,16 +212,12 @@ protected:
   /// created with.
   const TransformOptions &Options() { return GlobalOptions; }
 
-  /// \brief Provide access for subclasses for the container to store
-  /// translation unit replacements.
-  clang::tooling::Replacements &getReplacements() { return Replace; }
-
   /// \brief Affords a subclass to provide file contents overrides before
   /// applying frontend actions.
   ///
   /// It is an error not to call this function before calling ClangTool::run()
   /// with the factory provided by createActionFactory().
-  void setOverrides(FileOverrides &Overrides) {
+  void setOverrides(const FileOverrides &Overrides) {
     this->Overrides = &Overrides;
   }
 
@@ -219,8 +232,8 @@ protected:
 private:
   const std::string Name;
   const TransformOptions &GlobalOptions;
-  FileOverrides *Overrides;
-  clang::tooling::Replacements Replace;
+  const FileOverrides *Overrides;
+  TUReplacementsMap Replacements;
   std::string CurrentSource;
   TimingVec Timings;
   unsigned AcceptedChanges;