diff --git a/lib/Frontend/PrintPreprocessedOutput.cpp b/lib/Frontend/PrintPreprocessedOutput.cpp
new file mode 100644
index 0000000..43deaee
--- /dev/null
+++ b/lib/Frontend/PrintPreprocessedOutput.cpp
@@ -0,0 +1,519 @@
+//===--- PrintPreprocessedOutput.cpp - Implement the -E mode --------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This code simply runs the preprocessor on the input file and prints out the
+// result.  This is the traditional behavior of the -E option.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Frontend/Utils.h"
+#include "clang/Basic/Diagnostic.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Frontend/PreprocessorOutputOptions.h"
+#include "clang/Lex/MacroInfo.h"
+#include "clang/Lex/PPCallbacks.h"
+#include "clang/Lex/Pragma.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/Lex/TokenConcatenation.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/Config/config.h"
+#include "llvm/Support/raw_ostream.h"
+#include <cstdio>
+using namespace clang;
+
+/// PrintMacroDefinition - Print a macro definition in a form that will be
+/// properly accepted back as a definition.
+static void PrintMacroDefinition(const IdentifierInfo &II, const MacroInfo &MI,
+                                 Preprocessor &PP, llvm::raw_ostream &OS) {
+  OS << "#define " << II.getName();
+
+  if (MI.isFunctionLike()) {
+    OS << '(';
+    if (!MI.arg_empty()) {
+      MacroInfo::arg_iterator AI = MI.arg_begin(), E = MI.arg_end();
+      for (; AI+1 != E; ++AI) {
+        OS << (*AI)->getName();
+        OS << ',';
+      }
+
+      // Last argument.
+      if ((*AI)->getName() == "__VA_ARGS__")
+        OS << "...";
+      else
+        OS << (*AI)->getName();
+    }
+
+    if (MI.isGNUVarargs())
+      OS << "...";  // #define foo(x...)
+    
+    OS << ')';
+  }
+
+  // GCC always emits a space, even if the macro body is empty.  However, do not
+  // want to emit two spaces if the first token has a leading space.
+  if (MI.tokens_empty() || !MI.tokens_begin()->hasLeadingSpace())
+    OS << ' ';
+
+  llvm::SmallVector<char, 128> SpellingBuffer;
+  for (MacroInfo::tokens_iterator I = MI.tokens_begin(), E = MI.tokens_end();
+       I != E; ++I) {
+    if (I->hasLeadingSpace())
+      OS << ' ';
+
+    // Make sure we have enough space in the spelling buffer.
+    if (I->getLength() > SpellingBuffer.size())
+      SpellingBuffer.resize(I->getLength());
+    const char *Buffer = SpellingBuffer.data();
+    unsigned SpellingLen = PP.getSpelling(*I, Buffer);
+    OS.write(Buffer, SpellingLen);
+  }
+}
+
+//===----------------------------------------------------------------------===//
+// Preprocessed token printer
+//===----------------------------------------------------------------------===//
+
+namespace {
+class PrintPPOutputPPCallbacks : public PPCallbacks {
+  Preprocessor &PP;
+  TokenConcatenation ConcatInfo;
+public:
+  llvm::raw_ostream &OS;
+private:
+  unsigned CurLine;
+  bool EmittedTokensOnThisLine;
+  bool EmittedMacroOnThisLine;
+  SrcMgr::CharacteristicKind FileType;
+  llvm::SmallString<512> CurFilename;
+  bool Initialized;
+  bool DisableLineMarkers;
+  bool DumpDefines;
+  bool UseLineDirective;
+public:
+  PrintPPOutputPPCallbacks(Preprocessor &pp, llvm::raw_ostream &os,
+                           bool lineMarkers, bool defines)
+     : PP(pp), ConcatInfo(PP), OS(os), DisableLineMarkers(lineMarkers),
+       DumpDefines(defines) {
+    CurLine = 0;
+    CurFilename += "<uninit>";
+    EmittedTokensOnThisLine = false;
+    EmittedMacroOnThisLine = false;
+    FileType = SrcMgr::C_User;
+    Initialized = false;
+         
+    // If we're in microsoft mode, use normal #line instead of line markers.
+    UseLineDirective = PP.getLangOptions().Microsoft;
+  }
+
+  void SetEmittedTokensOnThisLine() { EmittedTokensOnThisLine = true; }
+  bool hasEmittedTokensOnThisLine() const { return EmittedTokensOnThisLine; }
+
+  virtual void FileChanged(SourceLocation Loc, FileChangeReason Reason,
+                           SrcMgr::CharacteristicKind FileType);
+  virtual void Ident(SourceLocation Loc, const std::string &str);
+  virtual void PragmaComment(SourceLocation Loc, const IdentifierInfo *Kind,
+                             const std::string &Str);
+
+
+  bool HandleFirstTokOnLine(Token &Tok);
+  bool MoveToLine(SourceLocation Loc);
+  bool AvoidConcat(const Token &PrevTok, const Token &Tok) {
+    return ConcatInfo.AvoidConcat(PrevTok, Tok);
+  }
+  void WriteLineInfo(unsigned LineNo, const char *Extra=0, unsigned ExtraLen=0);
+
+  void HandleNewlinesInToken(const char *TokStr, unsigned Len);
+
+  /// MacroDefined - This hook is called whenever a macro definition is seen.
+  void MacroDefined(const IdentifierInfo *II, const MacroInfo *MI);
+
+};
+}  // end anonymous namespace
+
+void PrintPPOutputPPCallbacks::WriteLineInfo(unsigned LineNo,
+                                             const char *Extra,
+                                             unsigned ExtraLen) {
+  if (EmittedTokensOnThisLine || EmittedMacroOnThisLine) {
+    OS << '\n';
+    EmittedTokensOnThisLine = false;
+    EmittedMacroOnThisLine = false;
+  }
+
+  // Emit #line directives or GNU line markers depending on what mode we're in.
+  if (UseLineDirective) {
+    OS << "#line" << ' ' << LineNo << ' ' << '"';
+    OS.write(&CurFilename[0], CurFilename.size());
+    OS << '"';
+  } else {
+    OS << '#' << ' ' << LineNo << ' ' << '"';
+    OS.write(&CurFilename[0], CurFilename.size());
+    OS << '"';
+    
+    if (ExtraLen)
+      OS.write(Extra, ExtraLen);
+
+    if (FileType == SrcMgr::C_System)
+      OS.write(" 3", 2);
+    else if (FileType == SrcMgr::C_ExternCSystem)
+      OS.write(" 3 4", 4);
+  }
+  OS << '\n';
+}
+
+/// MoveToLine - Move the output to the source line specified by the location
+/// object.  We can do this by emitting some number of \n's, or be emitting a
+/// #line directive.  This returns false if already at the specified line, true
+/// if some newlines were emitted.
+bool PrintPPOutputPPCallbacks::MoveToLine(SourceLocation Loc) {
+  unsigned LineNo = PP.getSourceManager().getInstantiationLineNumber(Loc);
+
+  if (DisableLineMarkers) {
+    if (LineNo == CurLine) return false;
+
+    CurLine = LineNo;
+
+    if (!EmittedTokensOnThisLine && !EmittedMacroOnThisLine)
+      return true;
+
+    OS << '\n';
+    EmittedTokensOnThisLine = false;
+    EmittedMacroOnThisLine = false;
+    return true;
+  }
+
+  // If this line is "close enough" to the original line, just print newlines,
+  // otherwise print a #line directive.
+  if (LineNo-CurLine <= 8) {
+    if (LineNo-CurLine == 1)
+      OS << '\n';
+    else if (LineNo == CurLine)
+      return false;    // Spelling line moved, but instantiation line didn't.
+    else {
+      const char *NewLines = "\n\n\n\n\n\n\n\n";
+      OS.write(NewLines, LineNo-CurLine);
+    }
+  } else {
+    WriteLineInfo(LineNo, 0, 0);
+  }
+
+  CurLine = LineNo;
+  return true;
+}
+
+
+/// FileChanged - Whenever the preprocessor enters or exits a #include file
+/// it invokes this handler.  Update our conception of the current source
+/// position.
+void PrintPPOutputPPCallbacks::FileChanged(SourceLocation Loc,
+                                           FileChangeReason Reason,
+                                       SrcMgr::CharacteristicKind NewFileType) {
+  // Unless we are exiting a #include, make sure to skip ahead to the line the
+  // #include directive was at.
+  SourceManager &SourceMgr = PP.getSourceManager();
+  if (Reason == PPCallbacks::EnterFile) {
+    SourceLocation IncludeLoc = SourceMgr.getPresumedLoc(Loc).getIncludeLoc();
+    if (IncludeLoc.isValid())
+      MoveToLine(IncludeLoc);
+  } else if (Reason == PPCallbacks::SystemHeaderPragma) {
+    MoveToLine(Loc);
+
+    // TODO GCC emits the # directive for this directive on the line AFTER the
+    // directive and emits a bunch of spaces that aren't needed.  Emulate this
+    // strange behavior.
+  }
+
+  Loc = SourceMgr.getInstantiationLoc(Loc);
+  // FIXME: Should use presumed line #!
+  CurLine = SourceMgr.getInstantiationLineNumber(Loc);
+
+  if (DisableLineMarkers) return;
+
+  CurFilename.clear();
+  CurFilename += SourceMgr.getPresumedLoc(Loc).getFilename();
+  Lexer::Stringify(CurFilename);
+  FileType = NewFileType;
+
+  if (!Initialized) {
+    WriteLineInfo(CurLine);
+    Initialized = true;
+  }
+
+  switch (Reason) {
+  case PPCallbacks::EnterFile:
+    WriteLineInfo(CurLine, " 1", 2);
+    break;
+  case PPCallbacks::ExitFile:
+    WriteLineInfo(CurLine, " 2", 2);
+    break;
+  case PPCallbacks::SystemHeaderPragma:
+  case PPCallbacks::RenameFile:
+    WriteLineInfo(CurLine);
+    break;
+  }
+}
+
+/// Ident - Handle #ident directives when read by the preprocessor.
+///
+void PrintPPOutputPPCallbacks::Ident(SourceLocation Loc, const std::string &S) {
+  MoveToLine(Loc);
+
+  OS.write("#ident ", strlen("#ident "));
+  OS.write(&S[0], S.size());
+  EmittedTokensOnThisLine = true;
+}
+
+/// MacroDefined - This hook is called whenever a macro definition is seen.
+void PrintPPOutputPPCallbacks::MacroDefined(const IdentifierInfo *II,
+                                            const MacroInfo *MI) {
+  // Only print out macro definitions in -dD mode.
+  if (!DumpDefines ||
+      // Ignore __FILE__ etc.
+      MI->isBuiltinMacro()) return;
+
+  MoveToLine(MI->getDefinitionLoc());
+  PrintMacroDefinition(*II, *MI, PP, OS);
+  EmittedMacroOnThisLine = true;
+}
+
+
+void PrintPPOutputPPCallbacks::PragmaComment(SourceLocation Loc,
+                                             const IdentifierInfo *Kind,
+                                             const std::string &Str) {
+  MoveToLine(Loc);
+  OS << "#pragma comment(" << Kind->getName();
+
+  if (!Str.empty()) {
+    OS << ", \"";
+
+    for (unsigned i = 0, e = Str.size(); i != e; ++i) {
+      unsigned char Char = Str[i];
+      if (isprint(Char) && Char != '\\' && Char != '"')
+        OS << (char)Char;
+      else  // Output anything hard as an octal escape.
+        OS << '\\'
+           << (char)('0'+ ((Char >> 6) & 7))
+           << (char)('0'+ ((Char >> 3) & 7))
+           << (char)('0'+ ((Char >> 0) & 7));
+    }
+    OS << '"';
+  }
+
+  OS << ')';
+  EmittedTokensOnThisLine = true;
+}
+
+
+/// HandleFirstTokOnLine - When emitting a preprocessed file in -E mode, this
+/// is called for the first token on each new line.  If this really is the start
+/// of a new logical line, handle it and return true, otherwise return false.
+/// This may not be the start of a logical line because the "start of line"
+/// marker is set for spelling lines, not instantiation ones.
+bool PrintPPOutputPPCallbacks::HandleFirstTokOnLine(Token &Tok) {
+  // Figure out what line we went to and insert the appropriate number of
+  // newline characters.
+  if (!MoveToLine(Tok.getLocation()))
+    return false;
+
+  // Print out space characters so that the first token on a line is
+  // indented for easy reading.
+  const SourceManager &SourceMgr = PP.getSourceManager();
+  unsigned ColNo = SourceMgr.getInstantiationColumnNumber(Tok.getLocation());
+
+  // This hack prevents stuff like:
+  // #define HASH #
+  // HASH define foo bar
+  // From having the # character end up at column 1, which makes it so it
+  // is not handled as a #define next time through the preprocessor if in
+  // -fpreprocessed mode.
+  if (ColNo <= 1 && Tok.is(tok::hash))
+    OS << ' ';
+
+  // Otherwise, indent the appropriate number of spaces.
+  for (; ColNo > 1; --ColNo)
+    OS << ' ';
+
+  return true;
+}
+
+void PrintPPOutputPPCallbacks::HandleNewlinesInToken(const char *TokStr,
+                                                     unsigned Len) {
+  unsigned NumNewlines = 0;
+  for (; Len; --Len, ++TokStr) {
+    if (*TokStr != '\n' &&
+        *TokStr != '\r')
+      continue;
+
+    ++NumNewlines;
+
+    // If we have \n\r or \r\n, skip both and count as one line.
+    if (Len != 1 &&
+        (TokStr[1] == '\n' || TokStr[1] == '\r') &&
+        TokStr[0] != TokStr[1])
+      ++TokStr, --Len;
+  }
+
+  if (NumNewlines == 0) return;
+
+  CurLine += NumNewlines;
+}
+
+
+namespace {
+struct UnknownPragmaHandler : public PragmaHandler {
+  const char *Prefix;
+  PrintPPOutputPPCallbacks *Callbacks;
+
+  UnknownPragmaHandler(const char *prefix, PrintPPOutputPPCallbacks *callbacks)
+    : PragmaHandler(0), Prefix(prefix), Callbacks(callbacks) {}
+  virtual void HandlePragma(Preprocessor &PP, Token &PragmaTok) {
+    // Figure out what line we went to and insert the appropriate number of
+    // newline characters.
+    Callbacks->MoveToLine(PragmaTok.getLocation());
+    Callbacks->OS.write(Prefix, strlen(Prefix));
+
+    // Read and print all of the pragma tokens.
+    while (PragmaTok.isNot(tok::eom)) {
+      if (PragmaTok.hasLeadingSpace())
+        Callbacks->OS << ' ';
+      std::string TokSpell = PP.getSpelling(PragmaTok);
+      Callbacks->OS.write(&TokSpell[0], TokSpell.size());
+      PP.LexUnexpandedToken(PragmaTok);
+    }
+    Callbacks->OS << '\n';
+  }
+};
+} // end anonymous namespace
+
+
+static void PrintPreprocessedTokens(Preprocessor &PP, Token &Tok,
+                                    PrintPPOutputPPCallbacks *Callbacks,
+                                    llvm::raw_ostream &OS) {
+  char Buffer[256];
+  Token PrevTok;
+  while (1) {
+
+    // If this token is at the start of a line, emit newlines if needed.
+    if (Tok.isAtStartOfLine() && Callbacks->HandleFirstTokOnLine(Tok)) {
+      // done.
+    } else if (Tok.hasLeadingSpace() ||
+               // If we haven't emitted a token on this line yet, PrevTok isn't
+               // useful to look at and no concatenation could happen anyway.
+               (Callbacks->hasEmittedTokensOnThisLine() &&
+                // Don't print "-" next to "-", it would form "--".
+                Callbacks->AvoidConcat(PrevTok, Tok))) {
+      OS << ' ';
+    }
+
+    if (IdentifierInfo *II = Tok.getIdentifierInfo()) {
+      OS << II->getName();
+    } else if (Tok.isLiteral() && !Tok.needsCleaning() &&
+               Tok.getLiteralData()) {
+      OS.write(Tok.getLiteralData(), Tok.getLength());
+    } else if (Tok.getLength() < 256) {
+      const char *TokPtr = Buffer;
+      unsigned Len = PP.getSpelling(Tok, TokPtr);
+      OS.write(TokPtr, Len);
+
+      // Tokens that can contain embedded newlines need to adjust our current
+      // line number.
+      if (Tok.getKind() == tok::comment)
+        Callbacks->HandleNewlinesInToken(TokPtr, Len);
+    } else {
+      std::string S = PP.getSpelling(Tok);
+      OS.write(&S[0], S.size());
+
+      // Tokens that can contain embedded newlines need to adjust our current
+      // line number.
+      if (Tok.getKind() == tok::comment)
+        Callbacks->HandleNewlinesInToken(&S[0], S.size());
+    }
+    Callbacks->SetEmittedTokensOnThisLine();
+
+    if (Tok.is(tok::eof)) break;
+
+    PrevTok = Tok;
+    PP.Lex(Tok);
+  }
+}
+
+typedef std::pair<IdentifierInfo*, MacroInfo*> id_macro_pair;
+static int MacroIDCompare(const void* a, const void* b) {
+  const id_macro_pair *LHS = static_cast<const id_macro_pair*>(a);
+  const id_macro_pair *RHS = static_cast<const id_macro_pair*>(b);
+  return LHS->first->getName().compare(RHS->first->getName());
+}
+
+static void DoPrintMacros(Preprocessor &PP, llvm::raw_ostream *OS) {
+  // -dM mode just scans and ignores all tokens in the files, then dumps out
+  // the macro table at the end.
+  PP.EnterMainSourceFile();
+
+  Token Tok;
+  do PP.Lex(Tok);
+  while (Tok.isNot(tok::eof));
+
+  llvm::SmallVector<id_macro_pair, 128>
+    MacrosByID(PP.macro_begin(), PP.macro_end());
+  llvm::array_pod_sort(MacrosByID.begin(), MacrosByID.end(), MacroIDCompare);
+
+  for (unsigned i = 0, e = MacrosByID.size(); i != e; ++i) {
+    MacroInfo &MI = *MacrosByID[i].second;
+    // Ignore computed macros like __LINE__ and friends.
+    if (MI.isBuiltinMacro()) continue;
+
+    PrintMacroDefinition(*MacrosByID[i].first, MI, PP, *OS);
+    *OS << '\n';
+  }
+}
+
+/// DoPrintPreprocessedInput - This implements -E mode.
+///
+void clang::DoPrintPreprocessedInput(Preprocessor &PP, llvm::raw_ostream *OS,
+                                     const PreprocessorOutputOptions &Opts) {
+  // Show macros with no output is handled specially.
+  if (!Opts.ShowCPP) {
+    assert(Opts.ShowMacros && "Not yet implemented!");
+    DoPrintMacros(PP, OS);
+    return;
+  }
+
+  // Inform the preprocessor whether we want it to retain comments or not, due
+  // to -C or -CC.
+  PP.SetCommentRetentionState(Opts.ShowComments, Opts.ShowMacroComments);
+
+  OS->SetBufferSize(64*1024);
+
+  PrintPPOutputPPCallbacks *Callbacks =
+      new PrintPPOutputPPCallbacks(PP, *OS, !Opts.ShowLineMarkers,
+                                   Opts.ShowMacros);
+  PP.AddPragmaHandler(0, new UnknownPragmaHandler("#pragma", Callbacks));
+  PP.AddPragmaHandler("GCC", new UnknownPragmaHandler("#pragma GCC",
+                                                      Callbacks));
+
+  PP.setPPCallbacks(Callbacks);
+
+  // After we have configured the preprocessor, enter the main file.
+  PP.EnterMainSourceFile();
+
+  // Consume all of the tokens that come from the predefines buffer.  Those
+  // should not be emitted into the output and are guaranteed to be at the
+  // start.
+  const SourceManager &SourceMgr = PP.getSourceManager();
+  Token Tok;
+  do PP.Lex(Tok);
+  while (Tok.isNot(tok::eof) && Tok.getLocation().isFileID() &&
+         !strcmp(SourceMgr.getPresumedLoc(Tok.getLocation()).getFilename(),
+                 "<built-in>"));
+
+  // Read all the preprocessed tokens, printing them out to the stream.
+  PrintPreprocessedTokens(PP, Tok, Callbacks, *OS);
+  *OS << '\n';
+}
+