10 files changed, 14722 insertions, 0 deletions

diff --git a/lib/Rewrite/Frontend/CMakeLists.txt b/lib/Rewrite/Frontend/CMakeLists.txt
new file mode 100644
index 0000000000..9017e479ab
--- /dev/null
+++ b/lib/Rewrite/Frontend/CMakeLists.txt
@@ -0,0 +1,28 @@
+add_clang_library(clangRewriteFrontend
+  FixItRewriter.cpp
+  FrontendActions.cpp
+  HTMLPrint.cpp
+  InclusionRewriter.cpp
+  RewriteMacros.cpp
+  RewriteModernObjC.cpp
+  RewriteObjC.cpp
+  RewriteTest.cpp
+  )
+
+add_dependencies(clangRewriteFrontend
+  ClangAttrClasses
+  ClangAttrList
+  ClangAttrParsedAttrList
+  ClangCommentNodes
+  ClangDeclNodes
+  ClangDiagnosticCommon
+  ClangDiagnosticFrontend
+  ClangStmtNodes
+  )
+
+target_link_libraries(clangRewriteFrontend
+  clangBasic
+  clangAST
+  clangParse
+  clangFrontend
+  )
diff --git a/lib/Rewrite/Frontend/FixItRewriter.cpp b/lib/Rewrite/Frontend/FixItRewriter.cpp
new file mode 100644
index 0000000000..43a1ab1ac1
--- /dev/null
+++ b/lib/Rewrite/Frontend/FixItRewriter.cpp
@@ -0,0 +1,205 @@
+//===--- FixItRewriter.cpp - Fix-It Rewriter Diagnostic Client --*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This is a diagnostic client adaptor that performs rewrites as
+// suggested by code modification hints attached to diagnostics. It
+// then forwards any diagnostics to the adapted diagnostic client.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Rewrite/Frontend/FixItRewriter.h"
+#include "clang/Edit/Commit.h"
+#include "clang/Edit/EditsReceiver.h"
+#include "clang/Basic/FileManager.h"
+#include "clang/Basic/SourceLocation.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Frontend/FrontendDiagnostic.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/Path.h"
+#include "llvm/ADT/OwningPtr.h"
+#include <cstdio>
+
+using namespace clang;
+
+FixItRewriter::FixItRewriter(DiagnosticsEngine &Diags, SourceManager &SourceMgr,
+                             const LangOptions &LangOpts,
+                             FixItOptions *FixItOpts)
+  : Diags(Diags),
+    Editor(SourceMgr, LangOpts),
+    Rewrite(SourceMgr, LangOpts),
+    FixItOpts(FixItOpts),
+    NumFailures(0),
+    PrevDiagSilenced(false) {
+  OwnsClient = Diags.ownsClient();
+  Client = Diags.takeClient();
+  Diags.setClient(this);
+}
+
+FixItRewriter::~FixItRewriter() {
+  Diags.takeClient();
+  Diags.setClient(Client, OwnsClient);
+}
+
+bool FixItRewriter::WriteFixedFile(FileID ID, raw_ostream &OS) {
+  const RewriteBuffer *RewriteBuf = Rewrite.getRewriteBufferFor(ID);
+  if (!RewriteBuf) return true;
+  RewriteBuf->write(OS);
+  OS.flush();
+  return false;
+}
+
+namespace {
+
+class RewritesReceiver : public edit::EditsReceiver {
+  Rewriter &Rewrite;
+
+public:
+  RewritesReceiver(Rewriter &Rewrite) : Rewrite(Rewrite) { }
+
+  virtual void insert(SourceLocation loc, StringRef text) {
+    Rewrite.InsertText(loc, text);
+  }
+  virtual void replace(CharSourceRange range, StringRef text) {
+    Rewrite.ReplaceText(range.getBegin(), Rewrite.getRangeSize(range), text);
+  }
+};
+
+}
+
+bool FixItRewriter::WriteFixedFiles(
+            std::vector<std::pair<std::string, std::string> > *RewrittenFiles) {
+  if (NumFailures > 0 && !FixItOpts->FixWhatYouCan) {
+    Diag(FullSourceLoc(), diag::warn_fixit_no_changes);
+    return true;
+  }
+
+  RewritesReceiver Rec(Rewrite);
+  Editor.applyRewrites(Rec);
+
+  for (iterator I = buffer_begin(), E = buffer_end(); I != E; ++I) {
+    const FileEntry *Entry = Rewrite.getSourceMgr().getFileEntryForID(I->first);
+    int fd;
+    std::string Filename = FixItOpts->RewriteFilename(Entry->getName(), fd);
+    std::string Err;
+    OwningPtr<llvm::raw_fd_ostream> OS;
+    if (fd != -1) {
+      OS.reset(new llvm::raw_fd_ostream(fd, /*shouldClose=*/true));
+    } else {
+      OS.reset(new llvm::raw_fd_ostream(Filename.c_str(), Err,
+                                        llvm::raw_fd_ostream::F_Binary));
+    }
+    if (!Err.empty()) {
+      Diags.Report(clang::diag::err_fe_unable_to_open_output)
+          << Filename << Err;
+      continue;
+    }
+    RewriteBuffer &RewriteBuf = I->second;
+    RewriteBuf.write(*OS);
+    OS->flush();
+
+    if (RewrittenFiles)
+      RewrittenFiles->push_back(std::make_pair(Entry->getName(), Filename));
+  }
+
+  return false;
+}
+
+bool FixItRewriter::IncludeInDiagnosticCounts() const {
+  return Client ? Client->IncludeInDiagnosticCounts() : true;
+}
+
+void FixItRewriter::HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
+                                     const Diagnostic &Info) {
+  // Default implementation (Warnings/errors count).
+  DiagnosticConsumer::HandleDiagnostic(DiagLevel, Info);
+
+  if (!FixItOpts->Silent ||
+      DiagLevel >= DiagnosticsEngine::Error ||
+      (DiagLevel == DiagnosticsEngine::Note && !PrevDiagSilenced) ||
+      (DiagLevel > DiagnosticsEngine::Note && Info.getNumFixItHints())) {
+    Client->HandleDiagnostic(DiagLevel, Info);
+    PrevDiagSilenced = false;
+  } else {
+    PrevDiagSilenced = true;
+  }
+
+  // Skip over any diagnostics that are ignored or notes.
+  if (DiagLevel <= DiagnosticsEngine::Note)
+    return;
+  // Skip over errors if we are only fixing warnings.
+  if (DiagLevel >= DiagnosticsEngine::Error && FixItOpts->FixOnlyWarnings) {
+    ++NumFailures;
+    return;
+  }
+
+  // Make sure that we can perform all of the modifications we
+  // in this diagnostic.
+  edit::Commit commit(Editor);
+  for (unsigned Idx = 0, Last = Info.getNumFixItHints();
+       Idx < Last; ++Idx) {
+    const FixItHint &Hint = Info.getFixItHint(Idx);
+
+    if (Hint.CodeToInsert.empty()) {
+      if (Hint.InsertFromRange.isValid())
+        commit.insertFromRange(Hint.RemoveRange.getBegin(),
+                           Hint.InsertFromRange, /*afterToken=*/false,
+                           Hint.BeforePreviousInsertions);
+      else
+        commit.remove(Hint.RemoveRange);
+    } else {
+      if (Hint.RemoveRange.isTokenRange() ||
+          Hint.RemoveRange.getBegin() != Hint.RemoveRange.getEnd())
+        commit.replace(Hint.RemoveRange, Hint.CodeToInsert);
+      else
+        commit.insert(Hint.RemoveRange.getBegin(), Hint.CodeToInsert,
+                    /*afterToken=*/false, Hint.BeforePreviousInsertions);
+    }
+  }
+  bool CanRewrite = Info.getNumFixItHints() > 0 && commit.isCommitable();
+
+  if (!CanRewrite) {
+    if (Info.getNumFixItHints() > 0)
+      Diag(Info.getLocation(), diag::note_fixit_in_macro);
+
+    // If this was an error, refuse to perform any rewriting.
+    if (DiagLevel >= DiagnosticsEngine::Error) {
+      if (++NumFailures == 1)
+        Diag(Info.getLocation(), diag::note_fixit_unfixed_error);
+    }
+    return;
+  }
+  
+  if (!Editor.commit(commit)) {
+    ++NumFailures;
+    Diag(Info.getLocation(), diag::note_fixit_failed);
+    return;
+  }
+
+  Diag(Info.getLocation(), diag::note_fixit_applied);
+}
+
+/// \brief Emit a diagnostic via the adapted diagnostic client.
+void FixItRewriter::Diag(SourceLocation Loc, unsigned DiagID) {
+  // When producing this diagnostic, we temporarily bypass ourselves,
+  // clear out any current diagnostic, and let the downstream client
+  // format the diagnostic.
+  Diags.takeClient();
+  Diags.setClient(Client);
+  Diags.Clear();
+  Diags.Report(Loc, DiagID);
+  Diags.takeClient();
+  Diags.setClient(this);
+}
+
+DiagnosticConsumer *FixItRewriter::clone(DiagnosticsEngine &Diags) const {
+  return new FixItRewriter(Diags, Diags.getSourceManager(), 
+                           Rewrite.getLangOpts(), FixItOpts);
+}
+
+FixItOptions::~FixItOptions() {}
diff --git a/lib/Rewrite/Frontend/FrontendActions.cpp b/lib/Rewrite/Frontend/FrontendActions.cpp
new file mode 100644
index 0000000000..7d29b6d421
--- /dev/null
+++ b/lib/Rewrite/Frontend/FrontendActions.cpp
@@ -0,0 +1,192 @@
+//===--- FrontendActions.cpp ----------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Rewrite/Frontend/FrontendActions.h"
+#include "clang/AST/ASTConsumer.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/Parse/Parser.h"
+#include "clang/Basic/FileManager.h"
+#include "clang/Frontend/FrontendActions.h"
+#include "clang/Frontend/CompilerInstance.h"
+#include "clang/Frontend/FrontendDiagnostic.h"
+#include "clang/Frontend/Utils.h"
+#include "clang/Rewrite/Frontend/ASTConsumers.h"
+#include "clang/Rewrite/Frontend/FixItRewriter.h"
+#include "clang/Rewrite/Frontend/Rewriters.h"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/FileSystem.h"
+
+using namespace clang;
+
+//===----------------------------------------------------------------------===//
+// AST Consumer Actions
+//===----------------------------------------------------------------------===//
+
+ASTConsumer *HTMLPrintAction::CreateASTConsumer(CompilerInstance &CI,
+                                                StringRef InFile) {
+  if (raw_ostream *OS = CI.createDefaultOutputFile(false, InFile))
+    return CreateHTMLPrinter(OS, CI.getPreprocessor());
+  return 0;
+}
+
+FixItAction::FixItAction() {}
+FixItAction::~FixItAction() {}
+
+ASTConsumer *FixItAction::CreateASTConsumer(CompilerInstance &CI,
+                                            StringRef InFile) {
+  return new ASTConsumer();
+}
+
+namespace {
+class FixItRewriteInPlace : public FixItOptions {
+public:
+  std::string RewriteFilename(const std::string &Filename, int &fd) {
+    fd = -1;
+    return Filename;
+  }
+};
+
+class FixItActionSuffixInserter : public FixItOptions {
+  std::string NewSuffix;
+
+public:
+  FixItActionSuffixInserter(std::string NewSuffix, bool FixWhatYouCan)
+    : NewSuffix(NewSuffix) {
+      this->FixWhatYouCan = FixWhatYouCan;
+  }
+
+  std::string RewriteFilename(const std::string &Filename, int &fd) {
+    fd = -1;
+    SmallString<128> Path(Filename);
+    llvm::sys::path::replace_extension(Path,
+      NewSuffix + llvm::sys::path::extension(Path));
+    return Path.str();
+  }
+};
+
+class FixItRewriteToTemp : public FixItOptions {
+public:
+  std::string RewriteFilename(const std::string &Filename, int &fd) {
+    SmallString<128> Path;
+    Path = llvm::sys::path::filename(Filename);
+    Path += "-%%%%%%%%";
+    Path += llvm::sys::path::extension(Filename);
+    SmallString<128> NewPath;
+    llvm::sys::fs::unique_file(Path.str(), fd, NewPath);
+    return NewPath.str();
+  }
+};
+} // end anonymous namespace
+
+bool FixItAction::BeginSourceFileAction(CompilerInstance &CI,
+                                        StringRef Filename) {
+  const FrontendOptions &FEOpts = getCompilerInstance().getFrontendOpts();
+  if (!FEOpts.FixItSuffix.empty()) {
+    FixItOpts.reset(new FixItActionSuffixInserter(FEOpts.FixItSuffix,
+                                                  FEOpts.FixWhatYouCan));
+  } else {
+    FixItOpts.reset(new FixItRewriteInPlace);
+    FixItOpts->FixWhatYouCan = FEOpts.FixWhatYouCan;
+  }
+  Rewriter.reset(new FixItRewriter(CI.getDiagnostics(), CI.getSourceManager(),
+                                   CI.getLangOpts(), FixItOpts.get()));
+  return true;
+}
+
+void FixItAction::EndSourceFileAction() {
+  // Otherwise rewrite all files.
+  Rewriter->WriteFixedFiles();
+}
+
+bool FixItRecompile::BeginInvocation(CompilerInstance &CI) {
+
+  std::vector<std::pair<std::string, std::string> > RewrittenFiles;
+  bool err = false;
+  {
+    const FrontendOptions &FEOpts = CI.getFrontendOpts();
+    OwningPtr<FrontendAction> FixAction(new SyntaxOnlyAction());
+    if (FixAction->BeginSourceFile(CI, FEOpts.Inputs[0])) {
+      OwningPtr<FixItOptions> FixItOpts;
+      if (FEOpts.FixToTemporaries)
+        FixItOpts.reset(new FixItRewriteToTemp());
+      else
+        FixItOpts.reset(new FixItRewriteInPlace());
+      FixItOpts->Silent = true;
+      FixItOpts->FixWhatYouCan = FEOpts.FixWhatYouCan;
+      FixItOpts->FixOnlyWarnings = FEOpts.FixOnlyWarnings;
+      FixItRewriter Rewriter(CI.getDiagnostics(), CI.getSourceManager(),
+                             CI.getLangOpts(), FixItOpts.get());
+      FixAction->Execute();
+  
+      err = Rewriter.WriteFixedFiles(&RewrittenFiles);
+    
+      FixAction->EndSourceFile();
+      CI.setSourceManager(0);
+      CI.setFileManager(0);
+    } else {
+      err = true;
+    }
+  }
+  if (err)
+    return false;
+  CI.getDiagnosticClient().clear();
+  CI.getDiagnostics().Reset();
+
+  PreprocessorOptions &PPOpts = CI.getPreprocessorOpts();
+  PPOpts.RemappedFiles.insert(PPOpts.RemappedFiles.end(),
+                              RewrittenFiles.begin(), RewrittenFiles.end());
+  PPOpts.RemappedFilesKeepOriginalName = false;
+
+  return true;
+}
+
+//===----------------------------------------------------------------------===//
+// Preprocessor Actions
+//===----------------------------------------------------------------------===//
+
+ASTConsumer *RewriteObjCAction::CreateASTConsumer(CompilerInstance &CI,
+                                                  StringRef InFile) {
+  if (raw_ostream *OS = CI.createDefaultOutputFile(false, InFile, "cpp")) {
+    if (CI.getLangOpts().ObjCRuntime.isNonFragile())
+      return CreateModernObjCRewriter(InFile, OS,
+                                CI.getDiagnostics(), CI.getLangOpts(),
+                                CI.getDiagnosticOpts().NoRewriteMacros);
+    return CreateObjCRewriter(InFile, OS,
+                              CI.getDiagnostics(), CI.getLangOpts(),
+                              CI.getDiagnosticOpts().NoRewriteMacros);
+  }
+  return 0;
+}
+
+void RewriteMacrosAction::ExecuteAction() {
+  CompilerInstance &CI = getCompilerInstance();
+  raw_ostream *OS = CI.createDefaultOutputFile(true, getCurrentFile());
+  if (!OS) return;
+
+  RewriteMacrosInInput(CI.getPreprocessor(), OS);
+}
+
+void RewriteTestAction::ExecuteAction() {
+  CompilerInstance &CI = getCompilerInstance();
+  raw_ostream *OS = CI.createDefaultOutputFile(false, getCurrentFile());
+  if (!OS) return;
+
+  DoRewriteTest(CI.getPreprocessor(), OS);
+}
+
+void RewriteIncludesAction::ExecuteAction() {
+  CompilerInstance &CI = getCompilerInstance();
+  raw_ostream *OS = CI.createDefaultOutputFile(true, getCurrentFile());
+  if (!OS) return;
+
+  RewriteIncludesInInput(CI.getPreprocessor(), OS,
+                         CI.getPreprocessorOutputOpts());
+}
diff --git a/lib/Rewrite/Frontend/HTMLPrint.cpp b/lib/Rewrite/Frontend/HTMLPrint.cpp
new file mode 100644
index 0000000000..79e44470ad
--- /dev/null
+++ b/lib/Rewrite/Frontend/HTMLPrint.cpp
@@ -0,0 +1,94 @@
+//===--- HTMLPrint.cpp - Source code -> HTML pretty-printing --------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Pretty-printing of source code to HTML.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Rewrite/Frontend/ASTConsumers.h"
+#include "clang/AST/ASTConsumer.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/Decl.h"
+#include "clang/Basic/Diagnostic.h"
+#include "clang/Basic/FileManager.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/Rewrite/Core/HTMLRewrite.h"
+#include "clang/Rewrite/Core/Rewriter.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/raw_ostream.h"
+using namespace clang;
+
+//===----------------------------------------------------------------------===//
+// Functional HTML pretty-printing.
+//===----------------------------------------------------------------------===//
+
+namespace {
+  class HTMLPrinter : public ASTConsumer {
+    Rewriter R;
+    raw_ostream *Out;
+    Preprocessor &PP;
+    bool SyntaxHighlight, HighlightMacros;
+
+  public:
+    HTMLPrinter(raw_ostream *OS, Preprocessor &pp,
+                bool _SyntaxHighlight, bool _HighlightMacros)
+      : Out(OS), PP(pp), SyntaxHighlight(_SyntaxHighlight),
+        HighlightMacros(_HighlightMacros) {}
+
+    void Initialize(ASTContext &context);
+    void HandleTranslationUnit(ASTContext &Ctx);
+  };
+}
+
+ASTConsumer* clang::CreateHTMLPrinter(raw_ostream *OS,
+                                      Preprocessor &PP,
+                                      bool SyntaxHighlight,
+                                      bool HighlightMacros) {
+  return new HTMLPrinter(OS, PP, SyntaxHighlight, HighlightMacros);
+}
+
+void HTMLPrinter::Initialize(ASTContext &context) {
+  R.setSourceMgr(context.getSourceManager(), context.getLangOpts());
+}
+
+void HTMLPrinter::HandleTranslationUnit(ASTContext &Ctx) {
+  if (PP.getDiagnostics().hasErrorOccurred())
+    return;
+
+  // Format the file.
+  FileID FID = R.getSourceMgr().getMainFileID();
+  const FileEntry* Entry = R.getSourceMgr().getFileEntryForID(FID);
+  const char* Name;
+  // In some cases, in particular the case where the input is from stdin,
+  // there is no entry.  Fall back to the memory buffer for a name in those
+  // cases.
+  if (Entry)
+    Name = Entry->getName();
+  else
+    Name = R.getSourceMgr().getBuffer(FID)->getBufferIdentifier();
+
+  html::AddLineNumbers(R, FID);
+  html::AddHeaderFooterInternalBuiltinCSS(R, FID, Name);
+
+  // If we have a preprocessor, relex the file and syntax highlight.
+  // We might not have a preprocessor if we come from a deserialized AST file,
+  // for example.
+
+  if (SyntaxHighlight) html::SyntaxHighlight(R, FID, PP);
+  if (HighlightMacros) html::HighlightMacros(R, FID, PP);
+  html::EscapeText(R, FID, false, true);
+
+  // Emit the HTML.
+  const RewriteBuffer &RewriteBuf = R.getEditBuffer(FID);
+  char *Buffer = (char*)malloc(RewriteBuf.size());
+  std::copy(RewriteBuf.begin(), RewriteBuf.end(), Buffer);
+  Out->write(Buffer, RewriteBuf.size());
+  free(Buffer);
+}
diff --git a/lib/Rewrite/Frontend/InclusionRewriter.cpp b/lib/Rewrite/Frontend/InclusionRewriter.cpp
new file mode 100644
index 0000000000..1929d72123
--- /dev/null
+++ b/lib/Rewrite/Frontend/InclusionRewriter.cpp
@@ -0,0 +1,361 @@
+//===--- InclusionRewriter.cpp - Rewrite includes into their expansions ---===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This code rewrites include invocations into their expansions.  This gives you
+// a file with all included files merged into it.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Rewrite/Frontend/Rewriters.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Frontend/PreprocessorOutputOptions.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace clang;
+using namespace llvm;
+
+namespace {
+
+class InclusionRewriter : public PPCallbacks {
+  /// Information about which #includes were actually performed,
+  /// created by preprocessor callbacks.
+  struct FileChange {
+    SourceLocation From;
+    FileID Id;
+    SrcMgr::CharacteristicKind FileType;
+    FileChange(SourceLocation From) : From(From) {
+    }
+  };
+  Preprocessor &PP; ///< Used to find inclusion directives.
+  SourceManager &SM; ///< Used to read and manage source files.
+  raw_ostream &OS; ///< The destination stream for rewritten contents.
+  bool ShowLineMarkers; ///< Show #line markers.
+  bool UseLineDirective; ///< Use of line directives or line markers.
+  typedef std::map<unsigned, FileChange> FileChangeMap;
+  FileChangeMap FileChanges; /// Tracks which files were included where.
+  /// Used transitively for building up the FileChanges mapping over the
+  /// various \c PPCallbacks callbacks.
+  FileChangeMap::iterator LastInsertedFileChange;
+public:
+  InclusionRewriter(Preprocessor &PP, raw_ostream &OS, bool ShowLineMarkers);
+  bool Process(FileID FileId, SrcMgr::CharacteristicKind FileType);
+private:
+  virtual void FileChanged(SourceLocation Loc, FileChangeReason Reason,
+                           SrcMgr::CharacteristicKind FileType,
+                           FileID PrevFID);
+  virtual void FileSkipped(const FileEntry &ParentFile,
+                           const Token &FilenameTok,
+                           SrcMgr::CharacteristicKind FileType);
+  virtual void InclusionDirective(SourceLocation HashLoc,
+                                  const Token &IncludeTok,
+                                  StringRef FileName,
+                                  bool IsAngled,
+                                  const FileEntry *File,
+                                  SourceLocation EndLoc,
+                                  StringRef SearchPath,
+                                  StringRef RelativePath);
+  void WriteLineInfo(const char *Filename, int Line,
+                     SrcMgr::CharacteristicKind FileType,
+                     StringRef EOL, StringRef Extra = StringRef());
+  void OutputContentUpTo(const MemoryBuffer &FromFile,
+                         unsigned &WriteFrom, unsigned WriteTo,
+                         StringRef EOL, int &lines,
+                         bool EnsureNewline = false);
+  void CommentOutDirective(Lexer &DirectivesLex, const Token &StartToken,
+                           const MemoryBuffer &FromFile, StringRef EOL,
+                           unsigned &NextToWrite, int &Lines);
+  const FileChange *FindFileChangeLocation(SourceLocation Loc) const;
+  StringRef NextIdentifierName(Lexer &RawLex, Token &RawToken);
+};
+
+}  // end anonymous namespace
+
+/// Initializes an InclusionRewriter with a \p PP source and \p OS destination.
+InclusionRewriter::InclusionRewriter(Preprocessor &PP, raw_ostream &OS,
+                                     bool ShowLineMarkers)
+    : PP(PP), SM(PP.getSourceManager()), OS(OS),
+    ShowLineMarkers(ShowLineMarkers),
+    LastInsertedFileChange(FileChanges.end()) {
+  // If we're in microsoft mode, use normal #line instead of line markers.
+  UseLineDirective = PP.getLangOpts().MicrosoftExt;
+}
+
+/// Write appropriate line information as either #line directives or GNU line
+/// markers depending on what mode we're in, including the \p Filename and
+/// \p Line we are located at, using the specified \p EOL line separator, and
+/// any \p Extra context specifiers in GNU line directives.
+void InclusionRewriter::WriteLineInfo(const char *Filename, int Line,
+                                      SrcMgr::CharacteristicKind FileType,
+                                      StringRef EOL, StringRef Extra) {
+  if (!ShowLineMarkers)
+    return;
+  if (UseLineDirective) {
+    OS << "#line" << ' ' << Line << ' ' << '"' << Filename << '"';
+  } else {
+    // Use GNU linemarkers as described here:
+    // http://gcc.gnu.org/onlinedocs/cpp/Preprocessor-Output.html
+    OS << '#' << ' ' << Line << ' ' << '"' << Filename << '"';
+    if (!Extra.empty())
+      OS << Extra;
+    if (FileType == SrcMgr::C_System)
+      // "`3' This indicates that the following text comes from a system header
+      // file, so certain warnings should be suppressed."
+      OS << " 3";
+    else if (FileType == SrcMgr::C_ExternCSystem)
+      // as above for `3', plus "`4' This indicates that the following text
+      // should be treated as being wrapped in an implicit extern "C" block."
+      OS << " 3 4";
+  }
+  OS << EOL;
+}
+
+/// FileChanged - Whenever the preprocessor enters or exits a #include file
+/// it invokes this handler.
+void InclusionRewriter::FileChanged(SourceLocation Loc,
+                                    FileChangeReason Reason,
+                                    SrcMgr::CharacteristicKind NewFileType,
+                                    FileID) {
+  if (Reason != EnterFile)
+    return;
+  if (LastInsertedFileChange == FileChanges.end())
+    // we didn't reach this file (eg: the main file) via an inclusion directive
+    return;
+  LastInsertedFileChange->second.Id = FullSourceLoc(Loc, SM).getFileID();
+  LastInsertedFileChange->second.FileType = NewFileType;
+  LastInsertedFileChange = FileChanges.end();
+}
+
+/// Called whenever an inclusion is skipped due to canonical header protection
+/// macros.
+void InclusionRewriter::FileSkipped(const FileEntry &/*ParentFile*/,
+                                    const Token &/*FilenameTok*/,
+                                    SrcMgr::CharacteristicKind /*FileType*/) {
+  assert(LastInsertedFileChange != FileChanges.end() && "A file, that wasn't "
+    "found via an inclusion directive, was skipped");
+  FileChanges.erase(LastInsertedFileChange);
+  LastInsertedFileChange = FileChanges.end();
+}
+
+/// This should be called whenever the preprocessor encounters include
+/// directives. It does not say whether the file has been included, but it
+/// provides more information about the directive (hash location instead
+/// of location inside the included file). It is assumed that the matching
+/// FileChanged() or FileSkipped() is called after this.
+void InclusionRewriter::InclusionDirective(SourceLocation HashLoc,
+                                           const Token &/*IncludeTok*/,
+                                           StringRef /*FileName*/,
+                                           bool /*IsAngled*/,
+                                           const FileEntry * /*File*/,
+                                           SourceLocation /*EndLoc*/,
+                                           StringRef /*SearchPath*/,
+                                           StringRef /*RelativePath*/) {
+  assert(LastInsertedFileChange == FileChanges.end() && "Another inclusion "
+    "directive was found before the previous one was processed");
+  std::pair<FileChangeMap::iterator, bool> p = FileChanges.insert(
+    std::make_pair(HashLoc.getRawEncoding(), FileChange(HashLoc)));
+  assert(p.second && "Unexpected revisitation of the same include directive");
+  LastInsertedFileChange = p.first;
+}
+
+/// Simple lookup for a SourceLocation (specifically one denoting the hash in
+/// an inclusion directive) in the map of inclusion information, FileChanges.
+const InclusionRewriter::FileChange *
+InclusionRewriter::FindFileChangeLocation(SourceLocation Loc) const {
+  FileChangeMap::const_iterator I = FileChanges.find(Loc.getRawEncoding());
+  if (I != FileChanges.end())
+    return &I->second;
+  return NULL;
+}
+
+/// Detect the likely line ending style of \p FromFile by examining the first
+/// newline found within it.
+static StringRef DetectEOL(const MemoryBuffer &FromFile) {
+  // detect what line endings the file uses, so that added content does not mix
+  // the style
+  const char *Pos = strchr(FromFile.getBufferStart(), '\n');
+  if (Pos == NULL)
+    return "\n";
+  if (Pos + 1 < FromFile.getBufferEnd() && Pos[1] == '\r')
+    return "\n\r";
+  if (Pos - 1 >= FromFile.getBufferStart() && Pos[-1] == '\r')
+    return "\r\n";
+  return "\n";
+}
+
+/// Writes out bytes from \p FromFile, starting at \p NextToWrite and ending at
+/// \p WriteTo - 1.
+void InclusionRewriter::OutputContentUpTo(const MemoryBuffer &FromFile,
+                                          unsigned &WriteFrom, unsigned WriteTo,
+                                          StringRef EOL, int &Line,
+                                          bool EnsureNewline) {
+  if (WriteTo <= WriteFrom)
+    return;
+  OS.write(FromFile.getBufferStart() + WriteFrom, WriteTo - WriteFrom);
+  // count lines manually, it's faster than getPresumedLoc()
+  Line += std::count(FromFile.getBufferStart() + WriteFrom,
+                     FromFile.getBufferStart() + WriteTo, '\n');
+  if (EnsureNewline) {
+    char LastChar = FromFile.getBufferStart()[WriteTo - 1];
+    if (LastChar != '\n' && LastChar != '\r')
+      OS << EOL;
+  }
+  WriteFrom = WriteTo;
+}
+
+/// Print characters from \p FromFile starting at \p NextToWrite up until the
+/// inclusion directive at \p StartToken, then print out the inclusion
+/// inclusion directive disabled by a #if directive, updating \p NextToWrite
+/// and \p Line to track the number of source lines visited and the progress
+/// through the \p FromFile buffer.
+void InclusionRewriter::CommentOutDirective(Lexer &DirectiveLex,
+                                            const Token &StartToken,
+                                            const MemoryBuffer &FromFile,
+                                            StringRef EOL,
+                                            unsigned &NextToWrite, int &Line) {
+  OutputContentUpTo(FromFile, NextToWrite,
+    SM.getFileOffset(StartToken.getLocation()), EOL, Line);
+  Token DirectiveToken;
+  do {
+    DirectiveLex.LexFromRawLexer(DirectiveToken);
+  } while (!DirectiveToken.is(tok::eod) && DirectiveToken.isNot(tok::eof));
+  OS << "#if 0 /* expanded by -frewrite-includes */" << EOL;
+  OutputContentUpTo(FromFile, NextToWrite,
+    SM.getFileOffset(DirectiveToken.getLocation()) + DirectiveToken.getLength(),
+    EOL, Line);
+  OS << "#endif /* expanded by -frewrite-includes */" << EOL;
+}
+
+/// Find the next identifier in the pragma directive specified by \p RawToken.
+StringRef InclusionRewriter::NextIdentifierName(Lexer &RawLex,
+                                                Token &RawToken) {
+  RawLex.LexFromRawLexer(RawToken);
+  if (RawToken.is(tok::raw_identifier))
+    PP.LookUpIdentifierInfo(RawToken);
+  if (RawToken.is(tok::identifier))
+    return RawToken.getIdentifierInfo()->getName();
+  return StringRef();
+}
+
+/// Use a raw lexer to analyze \p FileId, inccrementally copying parts of it
+/// and including content of included files recursively.
+bool InclusionRewriter::Process(FileID FileId,
+                                SrcMgr::CharacteristicKind FileType)
+{
+  bool Invalid;
+  const MemoryBuffer &FromFile = *SM.getBuffer(FileId, &Invalid);
+  if (Invalid) // invalid inclusion
+    return true;
+  const char *FileName = FromFile.getBufferIdentifier();
+  Lexer RawLex(FileId, &FromFile, PP.getSourceManager(), PP.getLangOpts());
+  RawLex.SetCommentRetentionState(false);
+
+  StringRef EOL = DetectEOL(FromFile);
+
+  // Per the GNU docs: "1" indicates the start of a new file.
+  WriteLineInfo(FileName, 1, FileType, EOL, " 1");
+
+  if (SM.getFileIDSize(FileId) == 0)
+    return true;
+
+  // The next byte to be copied from the source file
+  unsigned NextToWrite = 0;
+  int Line = 1; // The current input file line number.
+
+  Token RawToken;
+  RawLex.LexFromRawLexer(RawToken);
+
+  // TODO: Consider adding a switch that strips possibly unimportant content,
+  // such as comments, to reduce the size of repro files.
+  while (RawToken.isNot(tok::eof)) {
+    if (RawToken.is(tok::hash) && RawToken.isAtStartOfLine()) {
+      RawLex.setParsingPreprocessorDirective(true);
+      Token HashToken = RawToken;
+      RawLex.LexFromRawLexer(RawToken);
+      if (RawToken.is(tok::raw_identifier))
+        PP.LookUpIdentifierInfo(RawToken);
+      if (RawToken.is(tok::identifier)) {
+        switch (RawToken.getIdentifierInfo()->getPPKeywordID()) {
+          case tok::pp_include:
+          case tok::pp_include_next:
+          case tok::pp_import: {
+            CommentOutDirective(RawLex, HashToken, FromFile, EOL, NextToWrite,
+              Line);
+            if (const FileChange *Change = FindFileChangeLocation(
+                HashToken.getLocation())) {
+              // now include and recursively process the file
+              if (Process(Change->Id, Change->FileType))
+                // and set lineinfo back to this file, if the nested one was
+                // actually included
+                // `2' indicates returning to a file (after having included
+                // another file.
+                WriteLineInfo(FileName, Line, FileType, EOL, " 2");
+            } else
+              // fix up lineinfo (since commented out directive changed line
+              // numbers) for inclusions that were skipped due to header guards
+              WriteLineInfo(FileName, Line, FileType, EOL);
+            break;
+          }
+          case tok::pp_pragma: {
+            StringRef Identifier = NextIdentifierName(RawLex, RawToken);
+            if (Identifier == "clang" || Identifier == "GCC") {
+              if (NextIdentifierName(RawLex, RawToken) == "system_header") {
+                // keep the directive in, commented out
+                CommentOutDirective(RawLex, HashToken, FromFile, EOL,
+                  NextToWrite, Line);
+                // update our own type
+                FileType = SM.getFileCharacteristic(RawToken.getLocation());
+                WriteLineInfo(FileName, Line, FileType, EOL);
+              }
+            } else if (Identifier == "once") {
+              // keep the directive in, commented out
+              CommentOutDirective(RawLex, HashToken, FromFile, EOL,
+                NextToWrite, Line);
+              WriteLineInfo(FileName, Line, FileType, EOL);
+            }
+            break;
+          }
+          default:
+            break;
+        }
+      }
+      RawLex.setParsingPreprocessorDirective(false);
+    }
+    RawLex.LexFromRawLexer(RawToken);
+  }
+  OutputContentUpTo(FromFile, NextToWrite,
+    SM.getFileOffset(SM.getLocForEndOfFile(FileId)) + 1, EOL, Line,
+    /*EnsureNewline*/true);
+  return true;
+}
+
+/// InclusionRewriterInInput - Implement -frewrite-includes mode.
+void clang::RewriteIncludesInInput(Preprocessor &PP, raw_ostream *OS,
+                                   const PreprocessorOutputOptions &Opts) {
+  SourceManager &SM = PP.getSourceManager();
+  InclusionRewriter *Rewrite = new InclusionRewriter(PP, *OS,
+                                                     Opts.ShowLineMarkers);
+  PP.addPPCallbacks(Rewrite);
+
+  // First let the preprocessor process the entire file and call callbacks.
+  // Callbacks will record which #include's were actually performed.
+  PP.EnterMainSourceFile();
+  Token Tok;
+  // Only preprocessor directives matter here, so disable macro expansion
+  // everywhere else as an optimization.
+  // TODO: It would be even faster if the preprocessor could be switched
+  // to a mode where it would parse only preprocessor directives and comments,
+  // nothing else matters for parsing or processing.
+  PP.SetMacroExpansionOnlyInDirectives();
+  do {
+    PP.Lex(Tok);
+  } while (Tok.isNot(tok::eof));
+  Rewrite->Process(SM.getMainFileID(), SrcMgr::C_User);
+  OS->flush();
+}
diff --git a/lib/Rewrite/Frontend/Ma