Add the clang library to the repo (with some of my changes, too).

1 files changed, 3234 insertions, 0 deletions

diff --git a/clang/lib/Lex/Lexer.cpp b/clang/lib/Lex/Lexer.cpp
new file mode 100644
index 0000000..535a852
--- /dev/null
+++ b/clang/lib/Lex/Lexer.cpp
@@ -0,0 +1,3234 @@
+//===--- Lexer.cpp - C Language Family Lexer ------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file implements the Lexer and Token interfaces.
+//
+//===----------------------------------------------------------------------===//
+//
+// TODO: GCC Diagnostics emitted by the lexer:
+// PEDWARN: (form feed|vertical tab) in preprocessing directive
+//
+// Universal characters, unicode, char mapping:
+// WARNING: `%.*s' is not in NFKC
+// WARNING: `%.*s' is not in NFC
+//
+// Other:
+// TODO: Options to support:
+//    -fexec-charset,-fwide-exec-charset
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Lex/Lexer.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/Lex/LexDiagnostic.h"
+#include "clang/Lex/CodeCompletionHandler.h"
+#include "clang/Basic/SourceManager.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include <cstring>
+using namespace clang;
+
+static void InitCharacterInfo();
+
+//===----------------------------------------------------------------------===//
+// Token Class Implementation
+//===----------------------------------------------------------------------===//
+
+/// isObjCAtKeyword - Return true if we have an ObjC keyword identifier.
+bool Token::isObjCAtKeyword(tok::ObjCKeywordKind objcKey) const {
+  if (IdentifierInfo *II = getIdentifierInfo())
+    return II->getObjCKeywordID() == objcKey;
+  return false;
+}
+
+/// getObjCKeywordID - Return the ObjC keyword kind.
+tok::ObjCKeywordKind Token::getObjCKeywordID() const {
+  IdentifierInfo *specId = getIdentifierInfo();
+  return specId ? specId->getObjCKeywordID() : tok::objc_not_keyword;
+}
+
+
+//===----------------------------------------------------------------------===//
+// Lexer Class Implementation
+//===----------------------------------------------------------------------===//
+
+void Lexer::anchor() { }
+
+void Lexer::InitLexer(const char *BufStart, const char *BufPtr,
+                      const char *BufEnd) {
+  InitCharacterInfo();
+
+  BufferStart = BufStart;
+  BufferPtr = BufPtr;
+  BufferEnd = BufEnd;
+
+  assert(BufEnd[0] == 0 &&
+         "We assume that the input buffer has a null character at the end"
+         " to simplify lexing!");
+
+  // Check whether we have a BOM in the beginning of the buffer. If yes - act
+  // accordingly. Right now we support only UTF-8 with and without BOM, so, just
+  // skip the UTF-8 BOM if it's present.
+  if (BufferStart == BufferPtr) {
+    // Determine the size of the BOM.
+    StringRef Buf(BufferStart, BufferEnd - BufferStart);
+    size_t BOMLength = llvm::StringSwitch<size_t>(Buf)
+      .StartsWith("\xEF\xBB\xBF", 3) // UTF-8 BOM
+      .Default(0);
+
+    // Skip the BOM.
+    BufferPtr += BOMLength;
+  }
+
+  Is_PragmaLexer = false;
+  CurrentConflictMarkerState = CMK_None;
+
+  // Start of the file is a start of line.
+  IsAtStartOfLine = true;
+
+  // We are not after parsing a #.
+  ParsingPreprocessorDirective = false;
+
+  // We are not after parsing #include.
+  ParsingFilename = false;
+
+  // We are not in raw mode.  Raw mode disables diagnostics and interpretation
+  // of tokens (e.g. identifiers, thus disabling macro expansion).  It is used
+  // to quickly lex the tokens of the buffer, e.g. when handling a "#if 0" block
+  // or otherwise skipping over tokens.
+  LexingRawMode = false;
+
+  // Default to not keeping comments.
+  ExtendedTokenMode = 0;
+}
+
+/// Lexer constructor - Create a new lexer object for the specified buffer
+/// with the specified preprocessor managing the lexing process.  This lexer
+/// assumes that the associated file buffer and Preprocessor objects will
+/// outlive it, so it doesn't take ownership of either of them.
+Lexer::Lexer(FileID FID, const llvm::MemoryBuffer *InputFile, Preprocessor &PP)
+  : PreprocessorLexer(&PP, FID),
+    FileLoc(PP.getSourceManager().getLocForStartOfFile(FID)),
+    LangOpts(PP.getLangOpts()) {
+
+  InitLexer(InputFile->getBufferStart(), InputFile->getBufferStart(),
+            InputFile->getBufferEnd());
+
+  // Default to keeping comments if the preprocessor wants them.
+  SetCommentRetentionState(PP.getCommentRetentionState());
+}
+
+/// Lexer constructor - Create a new raw lexer object.  This object is only
+/// suitable for calls to 'LexRawToken'.  This lexer assumes that the text
+/// range will outlive it, so it doesn't take ownership of it.
+Lexer::Lexer(SourceLocation fileloc, const LangOptions &langOpts,
+             const char *BufStart, const char *BufPtr, const char *BufEnd)
+  : FileLoc(fileloc), LangOpts(langOpts) {
+
+  InitLexer(BufStart, BufPtr, BufEnd);
+
+  // We *are* in raw mode.
+  LexingRawMode = true;
+}
+
+/// Lexer constructor - Create a new raw lexer object.  This object is only
+/// suitable for calls to 'LexRawToken'.  This lexer assumes that the text
+/// range will outlive it, so it doesn't take ownership of it.
+Lexer::Lexer(FileID FID, const llvm::MemoryBuffer *FromFile,
+             const SourceManager &SM, const LangOptions &langOpts)
+  : FileLoc(SM.getLocForStartOfFile(FID)), LangOpts(langOpts) {
+
+  InitLexer(FromFile->getBufferStart(), FromFile->getBufferStart(),
+            FromFile->getBufferEnd());
+
+  // We *are* in raw mode.
+  LexingRawMode = true;
+}
+
+/// Create_PragmaLexer: Lexer constructor - Create a new lexer object for
+/// _Pragma expansion.  This has a variety of magic semantics that this method
+/// sets up.  It returns a new'd Lexer that must be delete'd when done.
+///
+/// On entrance to this routine, TokStartLoc is a macro location which has a
+/// spelling loc that indicates the bytes to be lexed for the token and an
+/// expansion location that indicates where all lexed tokens should be
+/// "expanded from".
+///
+/// FIXME: It would really be nice to make _Pragma just be a wrapper around a
+/// normal lexer that remaps tokens as they fly by.  This would require making
+/// Preprocessor::Lex virtual.  Given that, we could just dump in a magic lexer
+/// interface that could handle this stuff.  This would pull GetMappedTokenLoc
+/// out of the critical path of the lexer!
+///
+Lexer *Lexer::Create_PragmaLexer(SourceLocation SpellingLoc,
+                                 SourceLocation ExpansionLocStart,
+                                 SourceLocation ExpansionLocEnd,
+                                 unsigned TokLen, Preprocessor &PP) {
+  SourceManager &SM = PP.getSourceManager();
+
+  // Create the lexer as if we were going to lex the file normally.
+  FileID SpellingFID = SM.getFileID(SpellingLoc);
+  const llvm::MemoryBuffer *InputFile = SM.getBuffer(SpellingFID);
+  Lexer *L = new Lexer(SpellingFID, InputFile, PP);
+
+  // Now that the lexer is created, change the start/end locations so that we
+  // just lex the subsection of the file that we want.  This is lexing from a
+  // scratch buffer.
+  const char *StrData = SM.getCharacterData(SpellingLoc);
+
+  L->BufferPtr = StrData;
+  L->BufferEnd = StrData+TokLen;
+  assert(L->BufferEnd[0] == 0 && "Buffer is not nul terminated!");
+
+  // Set the SourceLocation with the remapping information.  This ensures that
+  // GetMappedTokenLoc will remap the tokens as they are lexed.
+  L->FileLoc = SM.createExpansionLoc(SM.getLocForStartOfFile(SpellingFID),
+                                     ExpansionLocStart,
+                                     ExpansionLocEnd, TokLen);
+
+  // Ensure that the lexer thinks it is inside a directive, so that end \n will
+  // return an EOD token.
+  L->ParsingPreprocessorDirective = true;
+
+  // This lexer really is for _Pragma.
+  L->Is_PragmaLexer = true;
+  return L;
+}
+
+
+/// Stringify - Convert the specified string into a C string, with surrounding
+/// ""'s, and with escaped \ and " characters.
+std::string Lexer::Stringify(const std::string &Str, bool Charify) {
+  std::string Result = Str;
+  char Quote = Charify ? '\'' : '"';
+  for (unsigned i = 0, e = Result.size(); i != e; ++i) {
+    if (Result[i] == '\\' || Result[i] == Quote) {
+      Result.insert(Result.begin()+i, '\\');
+      ++i; ++e;
+    }
+  }
+  return Result;
+}
+
+/// Stringify - Convert the specified string into a C string by escaping '\'
+/// and " characters.  This does not add surrounding ""'s to the string.
+void Lexer::Stringify(SmallVectorImpl<char> &Str) {
+  for (unsigned i = 0, e = Str.size(); i != e; ++i) {
+    if (Str[i] == '\\' || Str[i] == '"') {
+      Str.insert(Str.begin()+i, '\\');
+      ++i; ++e;
+    }
+  }
+}
+
+//===----------------------------------------------------------------------===//
+// Token Spelling
+//===----------------------------------------------------------------------===//
+
+/// getSpelling() - Return the 'spelling' of this token.  The spelling of a
+/// token are the characters used to represent the token in the source file
+/// after trigraph expansion and escaped-newline folding.  In particular, this
+/// wants to get the true, uncanonicalized, spelling of things like digraphs
+/// UCNs, etc.
+StringRef Lexer::getSpelling(SourceLocation loc,
+                                   SmallVectorImpl<char> &buffer,
+                                   const SourceManager &SM,
+                                   const LangOptions &options,
+                                   bool *invalid) {
+  // Break down the source location.
+  std::pair<FileID, unsigned> locInfo = SM.getDecomposedLoc(loc);
+
+  // Try to the load the file buffer.
+  bool invalidTemp = false;
+  StringRef file = SM.getBufferData(locInfo.first, &invalidTemp);
+  if (invalidTemp) {
+    if (invalid) *invalid = true;
+    return StringRef();
+  }
+
+  const char *tokenBegin = file.data() + locInfo.second;
+
+  // Lex from the start of the given location.
+  Lexer lexer(SM.getLocForStartOfFile(locInfo.first), options,
+              file.begin(), tokenBegin, file.end());
+  Token token;
+  lexer.LexFromRawLexer(token);
+
+  unsigned length = token.getLength();
+
+  // Common case:  no need for cleaning.
+  if (!token.needsCleaning())
+    return StringRef(tokenBegin, length);
+  
+  // Hard case, we need to relex the characters into the string.
+  buffer.clear();
+  buffer.reserve(length);
+  
+  for (const char *ti = tokenBegin, *te = ti + length; ti != te; ) {
+    unsigned charSize;
+    buffer.push_back(Lexer::getCharAndSizeNoWarn(ti, charSize, options));
+    ti += charSize;
+  }
+
+  return StringRef(buffer.data(), buffer.size());
+}
+
+/// getSpelling() - Return the 'spelling' of this token.  The spelling of a
+/// token are the characters used to represent the token in the source file
+/// after trigraph expansion and escaped-newline folding.  In particular, this
+/// wants to get the true, uncanonicalized, spelling of things like digraphs
+/// UCNs, etc.
+std::string Lexer::getSpelling(const Token &Tok, const SourceManager &SourceMgr,
+                               const LangOptions &LangOpts, bool *Invalid) {
+  assert((int)Tok.getLength() >= 0 && "Token character range is bogus!");
+  
+  // If this token contains nothing interesting, return it directly.
+  bool CharDataInvalid = false;
+  const char* TokStart = SourceMgr.getCharacterData(Tok.getLocation(), 
+                                                    &CharDataInvalid);
+  if (Invalid)
+    *Invalid = CharDataInvalid;
+  if (CharDataInvalid)
+    return std::string();
+  
+  if (!Tok.needsCleaning())
+    return std::string(TokStart, TokStart+Tok.getLength());
+  
+  std::string Result;
+  Result.reserve(Tok.getLength());
+  
+  // Otherwise, hard case, relex the characters into the string.
+  for (const char *Ptr = TokStart, *End = TokStart+Tok.getLength();
+       Ptr != End; ) {
+    unsigned CharSize;
+    Result.push_back(Lexer::getCharAndSizeNoWarn(Ptr, CharSize, LangOpts));
+    Ptr += CharSize;
+  }
+  assert(Result.size() != unsigned(Tok.getLength()) &&
+         "NeedsCleaning flag set on something that didn't need cleaning!");
+  return Result;
+}
+
+/// getSpelling - This method is used to get the spelling of a token into a
+/// preallocated buffer, instead of as an std::string.  The caller is required
+/// to allocate enough space for the token, which is guaranteed to be at least
+/// Tok.getLength() bytes long.  The actual length of the token is returned.
+///
+/// Note that this method may do two possible things: it may either fill in
+/// the buffer specified with characters, or it may *change the input pointer*
+/// to point to a constant buffer with the data already in it (avoiding a
+/// copy).  The caller is not allowed to modify the returned buffer pointer
+/// if an internal buffer is returned.
+unsigned Lexer::getSpelling(const Token &Tok, const char *&Buffer, 
+                            const SourceManager &SourceMgr,
+                            const LangOptions &LangOpts, bool *Invalid) {
+  assert((int)Tok.getLength() >= 0 && "Token character range is bogus!");
+
+  const char *TokStart = 0;
+  // NOTE: this has to be checked *before* testing for an IdentifierInfo.
+  if (Tok.is(tok::raw_identifier))
+    TokStart = Tok.getRawIdentifierData();
+  else if (const IdentifierInfo *II = Tok.getIdentifierInfo()) {
+    // Just return the string from the identifier table, which is very quick.
+    Buffer = II->getNameStart();
+    return II->getLength();
+  }
+
+  // NOTE: this can be checked even after testing for an IdentifierInfo.
+  if (Tok.isLiteral())
+    TokStart = Tok.getLiteralData();
+
+  if (TokStart == 0) {
+    // Compute the start of the token in the input lexer buffer.
+    bool CharDataInvalid = false;
+    TokStart = SourceMgr.getCharacterData(Tok.getLocation(), &CharDataInvalid);
+    if (Invalid)
+      *Invalid = CharDataInvalid;
+    if (CharDataInvalid) {
+      Buffer = "";
+      return 0;
+    }
+  }
+
+  // If this token contains nothing interesting, return it directly.
+  if (!Tok.needsCleaning()) {
+    Buffer = TokStart;
+    return Tok.getLength();
+  }
+
+  // Otherwise, hard case, relex the characters into the string.
+  char *OutBuf = const_cast<char*>(Buffer);
+  for (const char *Ptr = TokStart, *End = TokStart+Tok.getLength();
+       Ptr != End; ) {
+    unsigned CharSize;
+    *OutBuf++ = Lexer::getCharAndSizeNoWarn(Ptr, CharSize, LangOpts);
+    Ptr += CharSize;
+  }
+  assert(unsigned(OutBuf-Buffer) != Tok.getLength() &&
+         "NeedsCleaning flag set on something that didn't need cleaning!");
+
+  return OutBuf-Buffer;
+}
+
+
+
+static bool isWhitespace(unsigned char c);
+
+/// MeasureTokenLength - Relex the token at the specified location and return
+/// its length in bytes in the input file.  If the token needs cleaning (e.g.
+/// includes a trigraph or an escaped newline) then this count includes bytes
+/// that are part of that.
+unsigned Lexer::MeasureTokenLength(SourceLocation Loc,
+                                   const SourceManager &SM,
+                                   const LangOptions &LangOpts) {
+  // TODO: this could be special cased for common tokens like identifiers, ')',
+  // etc to make this faster, if it mattered.  Just look at StrData[0] to handle
+  // all obviously single-char tokens.  This could use
+  // Lexer::isObviouslySimpleCharacter for example to handle identifiers or
+  // something.
+
+  // If this comes from a macro expansion, we really do want the macro name, not
+  // the token this macro expanded to.
+  Loc = SM.getExpansionLoc(Loc);
+  std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(Loc);
+  bool Invalid = false;
+  StringRef Buffer = SM.getBufferData(LocInfo.first, &Invalid);
+  if (Invalid)
+    return 0;
+
+  const char *StrData = Buffer.data()+LocInfo.second;
+
+  if (isWhitespace(StrData[0]))
+    return 0;
+
+  // Create a lexer starting at the beginning of this token.
+  Lexer TheLexer(SM.getLocForStartOfFile(LocInfo.first), LangOpts,
+                 Buffer.begin(), StrData, Buffer.end());
+  TheLexer.SetCommentRetentionState(true);
+  Token TheTok;
+  TheLexer.LexFromRawLexer(TheTok);
+  return TheTok.getLength();
+}
+
+static SourceLocation getBeginningOfFileToken(SourceLocation Loc,
+                                              const SourceManager &SM,
+                                              const LangOptions &LangOpts) {
+  assert(Loc.isFileID());
+  std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(Loc);
+  if (LocInfo.first.isInvalid())
+    return Loc;
+  
+  bool Invalid = false;
+  StringRef Buffer = SM.getBufferData(LocInfo.first, &Invalid);
+  if (Invalid)
+    return Loc;
+
+  // Back up from the current location until we hit the beginning of a line
+  // (or the buffer). We'll relex from that point.
+  const char *BufStart = Buffer.data();
+  if (LocInfo.second >= Buffer.size())
+    return Loc;
+  
+  const char *StrData = BufStart+LocInfo.second;
+  if (StrData[0] == '\n' || StrData[0] == '\r')
+    return Loc;
+
+  const char *LexStart = StrData;
+  while (LexStart != BufStart) {
+    if (LexStart[0] == '\n' || LexStart[0] == '\r') {
+      ++LexStart;
+      break;
+    }
+
+    --LexStart;
+  }
+  
+  // Create a lexer starting at the beginning of this token.
+  SourceLocation LexerStartLoc = Loc.getLocWithOffset(-LocInfo.second);
+  Lexer TheLexer(LexerStartLoc, LangOpts, BufStart, LexStart, Buffer.end());
+  TheLexer.SetCommentRetentionState(true);
+  
+  // Lex tokens until we find the token that contains the source location.
+  Token TheTok;
+  do {
+    TheLexer.LexFromRawLexer(TheTok);
+    
+    if (TheLexer.getBufferLocation() > StrData) {
+      // Lexing this token has taken the lexer past the source location we're
+      // looking for. If the current token encompasses our source location,
+      // return the beginning of that token.
+      if (TheLexer.getBufferLocation() - TheTok.getLength() <= StrData)
+        return TheTok.getLocation();
+      
+      // We ended up skipping over the source location entirely, which means
+      // that it points into whitespace. We're done here.
+      break;
+    }
+  } while (TheTok.getKind() != tok::eof);
+  
+  // We've passed our source location; just return the original source location.
+  return Loc;
+}
+
+SourceLocation Lexer::GetBeginningOfToken(SourceLocation Loc,
+                                          const SourceManager &SM,
+                                          const LangOptions &LangOpts) {
+ if (Loc.isFileID())
+   return getBeginningOfFileToken(Loc, SM, LangOpts);
+ 
+ if (!SM.isMacroArgExpansion(Loc))
+   return Loc;
+
+ SourceLocation FileLoc = SM.getSpellingLoc(Loc);
+ SourceLocation BeginFileLoc = getBeginningOfFileToken(FileLoc, SM, LangOpts);
+ std::pair<FileID, unsigned> FileLocInfo = SM.getDecomposedLoc(FileLoc);
+ std::pair<FileID, unsigned> BeginFileLocInfo
+   = SM.getDecomposedLoc(BeginFileLoc);
+ assert(FileLocInfo.first == BeginFileLocInfo.first &&
+        FileLocInfo.second >= BeginFileLocInfo.second);
+ return Loc.getLocWithOffset(BeginFileLocInfo.second - FileLocInfo.second);
+}
+
+namespace {
+  enum PreambleDirectiveKind {
+    PDK_Skipped,
+    PDK_StartIf,
+    PDK_EndIf,
+    PDK_Unknown
+  };
+}
+
+std::pair<unsigned, bool>
+Lexer::ComputePreamble(const llvm::MemoryBuffer *Buffer,
+                       const LangOptions &LangOpts, unsigned MaxLines) {
+  // Create a lexer starting at the beginning of the file. Note that we use a
+  // "fake" file source location at offset 1 so that the lexer will track our
+  // position within the file.
+  const unsigned StartOffset = 1;
+  SourceLocation StartLoc = SourceLocation::getFromRawEncoding(StartOffset);
+  Lexer TheLexer(StartLoc, LangOpts, Buffer->getBufferStart(),
+                 Buffer->getBufferStart(), Buffer->getBufferEnd());
+  
+  bool InPreprocessorDirective = false;
+  Token TheTok;
+  Token IfStartTok;
+  unsigned IfCount = 0;
+
+  unsigned MaxLineOffset = 0;
+  if (MaxLines) {
+    const char *CurPtr = Buffer->getBufferStart();
+    unsigned CurLine = 0;
+    while (CurPtr != Buffer->getBufferEnd()) {
+      char ch = *CurPtr++;
+      if (ch == '\n') {
+        ++CurLine;
+        if (CurLine == MaxLines)
+          break;
+      }
+    }
+    if (CurPtr != Buffer->getBufferEnd())
+      MaxLineOffset = CurPtr - Buffer->getBufferStart();
+  }
+
+  do {
+    TheLexer.LexFromRawLexer(TheTok);
+
+    if (InPreprocessorDirective) {
+      // If we've hit the end of the file, we're done.
+      if (TheTok.getKind() == tok::eof) {
+        InPreprocessorDirective = false;
+        break;
+      }
+      
+      // If we haven't hit the end of the preprocessor directive, skip this
+      // token.
+      if (!TheTok.isAtStartOfLine())
+        continue;
+        
+      // We've passed the end of the preprocessor directive, and will look
+      // at this token again below.
+      InPreprocessorDirective = false;
+    }
+    
+    // Keep track of the # of lines in the preamble.
+    if (TheTok.isAtStartOfLine()) {
+      unsigned TokOffset = TheTok.getLocation().getRawEncoding() - StartOffset;
+
+      // If we were asked to limit the number of lines in the preamble,
+      // and we're about to exceed that limit, we're done.
+      if (MaxLineOffset && TokOffset >= MaxLineOffset)
+        break;
+    }
+
+    // Comments are okay; skip over them.
+    if (TheTok.getKind() == tok::comment)
+      continue;
+    
+    if (TheTok.isAtStartOfLine() && TheTok.getKind() == tok::hash) {
+      // This is the start of a preprocessor directive. 
+      Token HashTok = TheTok;
+      InPreprocessorDirective = true;
+      
+      // Figure out which directive this is. Since we're lexing raw tokens,
+      // we don't have an identifier table available. Instead, just look at
+      // the raw identifier to recognize and categorize preprocessor directives.
+      TheLexer.LexFromRawLexer(TheTok);
+      if (TheTok.getKind() == tok::raw_identifier && !TheTok.needsCleaning()) {
+        StringRef Keyword(TheTok.getRawIdentifierData(),
+                                TheTok.getLength());
+        PreambleDirectiveKind PDK
+          = llvm::StringSwitch<PreambleDirectiveKind>(Keyword)
+              .Case("include", PDK_Skipped)
+              .Case("__include_macros", PDK_Skipped)
+              .Case("define", PDK_Skipped)
+              .Case("undef", PDK_Skipped)
+              .Case("line", PDK_Skipped)
+              .Case("error", PDK_Skipped)
+              .Case("pragma", PDK_Skipped)
+              .Case("import", PDK_Skipped)
+              .Case("include_next", PDK_Skipped)
+              .Case("warning", PDK_Skipped)
+              .Case("ident", PDK_Skipped)
+              .Case("sccs", PDK_Skipped)
+              .Case("assert", PDK_Skipped)
+              .Case("unassert", PDK_Skipped)
+              .Case("if", PDK_StartIf)
+              .Case("ifdef", PDK_StartIf)
+              .Case("ifndef", PDK_StartIf)
+              .Case("elif", PDK_Skipped)
+              .Case("else", PDK_Skipped)
+              .Case("endif", PDK_EndIf)
+              .Default(PDK_Unknown);
+
+        switch (PDK) {
+        case PDK_Skipped:
+          continue;
+
+        case PDK_StartIf:
+          if (IfCount == 0)
+            IfStartTok = HashTok;
+            
+          ++IfCount;
+          continue;
+            
+        case PDK_EndIf:
+          // Mismatched #endif. The preamble ends here.
+          if (IfCount == 0)
+            break;
+
+          --IfCount;
+          continue;
+            
+        case PDK_Unknown:
+          // We don't know what this directive is; stop at the '#'.
+          break;
+        }
+      }
+      
+      // We only end up here if we didn't recognize the preprocessor
+      // directive or it was one that can't occur in the preamble at this
+      // point. Roll back the current token to the location of the '#'.
+      InPreprocessorDirective = false;
+      TheTok = HashTok;
+    }
+
+    // We hit a token that we don't recognize as being in the
+    // "preprocessing only" part of the file, so we're no longer in
+    // the preamble.
+    break;
+  } while (true);
+  
+  SourceLocation End = IfCount? IfStartTok.getLocation() : TheTok.getLocation();
+  return std::make_pair(End.getRawEncoding() - StartLoc.getRawEncoding(),
+                        IfCount? IfStartTok.isAtStartOfLine()
+                               : TheTok.isAtStartOfLine());
+}
+
+
+/// AdvanceToTokenCharacter - Given a location that specifies the start of a
+/// token, return a new location that specifies a character within the token.
+SourceLocation Lexer::AdvanceToTokenCharacter(SourceLocation TokStart,
+                                              unsigned CharNo,
+                                              const SourceManager &SM,
+                                              const LangOptions &LangOpts) {
+  // Figure out how many physical characters away the specified expansion
+  // character is.  This needs to take into consideration newlines and
+  // trigraphs.
+  bool Invalid = false;
+  const char *TokPtr = SM.getCharacterData(TokStart, &Invalid);
+  
+  // If they request the first char of the token, we're trivially done.
+  if (Invalid || (CharNo == 0 && Lexer::isObviouslySimpleCharacter(*TokPtr)))
+    return TokStart;
+  
+  unsigned PhysOffset = 0;
+  
+  // The usual case is that tokens don't contain anything interesting.  Skip
+  // over the uninteresting characters.  If a token only consists of simple
+  // chars, this method is extremely fast.
+  while (Lexer::isObviouslySimpleCharacter(*TokPtr)) {
+    if (CharNo == 0)
+      return TokStart.getLocWithOffset(PhysOffset);
+    ++TokPtr, --CharNo, ++PhysOffset;
+  }
+  
+  // If we have a character that may be a trigraph or escaped newline, use a
+  // lexer to parse it correctly.
+  for (; CharNo; --CharNo) {
+    unsigned Size;
+    Lexer::getCharAndSizeNoWarn(TokPtr, Size, LangOpts);
+    TokPtr += Size;
+    PhysOffset += Size;
+  }
+  
+  // Final detail: if we end up on an escaped newline, we want to return the
+  // location of the actual byte of the token.  For example foo\<newline>bar
+  // advanced by 3 should return the location of b, not of \\.  One compounding
+  // detail of this is that the escape may be made by a trigraph.
+  if (!Lexer::isObviouslySimpleCharacter(*TokPtr))
+    PhysOffset += Lexer::SkipEscapedNewLines(TokPtr)-TokPtr;
+  
+  return TokStart.getLocWithOffset(PhysOffset);
+}
+
+/// \brief Computes the source location just past the end of the
+/// token at this source location.
+///
+/// This routine can be used to produce a source location that
+/// points just past the end of the token referenced by \p Loc, and
+/// is generally used when a diagnostic needs to point just after a
+/// token where it expected something different that it received. If
+/// the returned source location would not be meaningful (e.g., if
+/// it points into a macro), this routine returns an invalid
+/// source location.
+///
+/// \param Offset an offset from the end of the token, where the source
+/// location should refer to. The default offset (0) produces a source
+/// location pointing just past the end of the token; an offset of 1 produces
+/// a source location pointing to the last character in the token, etc.
+SourceLocation Lexer::getLocForEndOfToken(SourceLocation Loc, unsigned Offset,
+                                          const SourceManager &SM,
+                                          const LangOptions &LangOpts) {
+  if (Loc.isInvalid())
+    return SourceLocation();
+
+  if (Loc.isMacroID()) {
+    if (Offset > 0 || !isAtEndOfMacroExpansion(Loc, SM, LangOpts, &Loc))
+      return SourceLocation(); // Points inside the macro expansion.
+  }
+
+  unsigned Len = Lexer::MeasureTokenLength(Loc, SM, LangOpts);
+  if (Len > Offset)
+    Len = Len - Offset;
+  else
+    return Loc;
+  
+  return Loc.getLocWithOffset(Len);
+}
+
+/// \brief Returns true if the given MacroID location points at the first
+/// token of the macro expansion.
+bool Lexer::isAtStartOfMacroExpansion(SourceLocation loc,
+                                      const SourceManager &SM,
+                                      const LangOptions &LangOpts,
+                                      SourceLocation *MacroBegin) {
+  assert(loc.isValid() && loc.isMacroID() && "Expected a valid macro loc");
+
+  std::pair<FileID, unsigned> infoLoc = SM.getDecomposedLoc(loc);
+  // FIXME: If the token comes from the macro token paste operator ('##')
+  // this function will always return false;
+  if (infoLoc.second > 0)
+    return false; // Does not point at the start of token.
+
+  SourceLocation expansionLoc =
+    SM.getSLocEntry(infoLoc.first).getExpansion().getExpansionLocStart();
+  if (expansionLoc.isFileID()) {
+    // No other macro expansions, this is the first.
+    if (MacroBegin)
+      *MacroBegin = expansionLoc;
+    return true;
+  }
+
+  return isAtStartOfMacroExpansion(expansionLoc, SM, LangOpts, MacroBegin);
+}
+
+/// \brief Returns true if the given MacroID location points at the last
+/// token of the macro expansion.
+bool Lexer::isAtEndOfMacroExpansion(SourceLocation loc,
+                                    const SourceManager &SM,
+                                    const LangOptions &LangOpts,
+                                    SourceLocation *MacroEnd) {
+  assert(loc.isValid() && loc.isMacroID() && "Expected a valid macro loc");
+
+  SourceLocation spellLoc = SM.getSpellingLoc(loc);
+  unsigned tokLen = MeasureTokenLength(spellLoc, SM, LangOpts);
+  if (tokLen == 0)
+    return false;
+
+  FileID FID = SM.getFileID(loc);
+  SourceLocation afterLoc = loc.getLocWithOffset(tokLen+1);
+  if (SM.isInFileID(afterLoc, FID))
+    return false; // Still in the same FileID, does not point to the last token.
+
+  // FIXME: If the token comes from the macro token paste operator ('##')
+  // or the stringify operator ('#') this function will always return false;
+
+  SourceLocation expansionLoc =
+    SM.getSLocEntry(FID).getExpansion().getExpansionLocEnd();
+  if (expansionLoc.isFileID()) {
+    // No other macro expansions.
+    if (MacroEnd)
+      *MacroEnd = expansionLoc;
+    return true;
+  }
+
+  return isAtEndOfMacroExpansion(expansionLoc, SM, LangOpts, MacroEnd);
+}
+
+static CharSourceRange makeRangeFromFileLocs(CharSourceRange Range,
+                                             const SourceManager &SM,
+                                             const LangOptions &LangOpts) {
+  SourceLocation Begin = Range.getBegin();
+  SourceLocation End = Range.getEnd();
+  assert(Begin.isFileID() && End.isFileID());
+  if (Range.isTokenRange()) {
+    End = Lexer::getLocForEndOfToken(End, 0, SM,LangOpts);
+    if (End.isInvalid())
+      return CharSourceRange();
+  }
+
+  // Break down the source locations.
+  FileID FID;
+  unsigned BeginOffs;
+  llvm::tie(FID, BeginOffs) = SM.getDecomposedLoc(Begin);
+  if (FID.isInvalid())
+    return CharSourceRange();
+
+  unsigned EndOffs;
+  if (!SM.isInFileID(End, FID, &EndOffs) ||
+      BeginOffs > EndOffs)
+    return CharSourceRange();
+
+  return CharSourceRange::getCharRange(Begin, End);
+}
+
+/// \brief Accepts a range and returns a character range with file locations.
+///
+/// Returns a null range if a part of the range resides inside a macro
+/// expansion or the range does not reside on the same FileID.
+CharSourceRange Lexer::makeFileCharRange(CharSourceRange Range,
+                                         const SourceManager &SM,
+                                         const LangOptions &LangOpts) {
+  SourceLocation Begin = Range.getBegin();
+  SourceLocation End = Range.getEnd();
+  if (Begin.isInvalid() || End.isInvalid())
+    return CharSourceRange();
+
+  if (Begin.isFileID() && End.isFileID())
+    return makeRangeFromFileLocs(Range, SM, LangOpts);
+
+  if (Begin.isMacroID() && End.isFileID()) {
+    if (!isAtStartOfMacroExpansion(Begin, SM, LangOpts, &Begin))
+      return CharSourceRange();
+    Range.setBegin(Begin);
+    return makeRangeFromFileLocs(Range, SM, LangOpts);
+  }
+
+  if (Begin.isFileID() && End.isMacroID()) {
+    if ((Range.isTokenRange() && !isAtEndOfMacroExpansion(End, SM, LangOpts,
+                                                          &End)) ||
+        (Range.isCharRange() && !isAtStartOfMacroExpansion(End, SM, LangOpts,
+                                                           &End)))
+      return CharSourceRange();
+    Range.setEnd(End);
+    return makeRangeFromFileLocs(Range, SM, LangOpts);
+  }
+
+  assert(Begin.isMacroID() && End.isMacroID());
+  SourceLocation MacroBegin, MacroEnd;
+  if (isAtStartOfMacroExpansion(Begin, SM, LangOpts, &MacroBegin) &&
+      ((Range.isTokenRange() && isAtEndOfMacroExpansion(End, SM, LangOpts,
+                                                        &MacroEnd)) ||
+       (Range.isCharRange() && isAtStartOfMacroExpansion(End, SM, LangOpts,
+                                                         &MacroEnd)))) {
+    Range.setBegin(MacroBegin);
+    Range.setEnd(MacroEnd);
+    return makeRangeFromFileLocs(Range, SM, LangOpts);
+  }
+
+  FileID FID;
+  unsigned BeginOffs;
+  llvm::tie(FID, BeginOffs) = SM.getDecomposedLoc(Begin);
+  if (FID.isInvalid())
+    return CharSourceRange();
+
+  unsigned EndOffs;
+  if (!SM.isInFileID(End, FID, &EndOffs) ||
+      BeginOffs > EndOffs)
+    return CharSourceRange();
+
+  const SrcMgr::SLocEntry *E = &SM.getSLocEntry(FID);
+  const SrcMgr::ExpansionInfo &Expansion = E->getExpansion();
+  if (Expansion.isMacroArgExpansion() &&
+      Expansion.getSpellingLoc().isFileID()) {
+    SourceLocation SpellLoc = Expansion.getSpellingLoc();
+    Range.setBegin(SpellLoc.getLocWithOffset(BeginOffs));
+    Range.setEnd(SpellLoc.getLocWithOffset(EndOffs));
+    return makeRangeFromFileLocs(Range, SM, LangOpts);
+  }
+
+  return CharSourceRange();
+}
+
+StringRef Lexer::getSourceText(CharSourceRange Range,
+                               const SourceManager &SM,
+                               const LangOptions &LangOpts,
+                               bool *Invalid) {
+  Range = makeFileCharRange(Range, SM, LangOpts);
+  if (Range.isInvalid()) {
+    if (Invalid) *Invalid = true;
+    return StringRef();
+  }
+
+  // Break down the source location.
+  std::pair<FileID, unsigned> beginInfo = SM.getDecomposedLoc(Range.getBegin());
+  if (beginInfo.first.isInvalid()) {
+    if (Invalid) *Invalid = true;
+    return StringRef();
+  }
+
+  unsigned EndOffs;
+  if (!SM.isInFileID(Range.getEnd(), beginInfo.first, &EndOffs) ||
+      beginInfo.second > EndOffs) {
+    if (Invalid) *Invalid = true;
+    return StringRef();
+  }
+
+  // Try to the load the file buffer.
+  bool invalidTemp = false;
+  StringRef file = SM.getBufferData(beginInfo.first, &invalidTemp);
+  if (invalidTemp) {
+    if (Invalid) *Invalid = true;
+    return StringRef();
+  }
+
+  if (Invalid) *Invalid = false;
+  return file.substr(beginInfo.second, EndOffs - beginInfo.second);
+}
+
+StringRef Lexer::getImmediateMacroName(SourceLocation Loc,
+                                       const SourceManager &SM,
+                                       const LangOptions &LangOpts) {
+  assert(Loc.isMacroID() && "Only reasonble to call this on macros");
+
+  // Find the location of the immediate macro expansion.
+  while (1) {
+    FileID FID = SM.getFileID(Loc);
+    const SrcMgr::SLocEntry *E = &SM.getSLocEntry(FID);
+    const SrcMgr::ExpansionInfo &Expansion = E->getExpansion();
+    Loc = Expansion.getExpansionLocStart();
+    if (!Expansion.isMacroArgExpansion())
+      break;
+
+    // For macro arguments we need to check that the argument did not come
+    // from an inner macro, e.g: "MAC1( MAC2(foo) )"
+    
+    // Loc points to the argument id of the macro definition, move to the
+    // macro expansion.
+    Loc = SM.getImmediateExpansionRange(Loc).first;
+    SourceLocation SpellLoc = Expansion.getSpellingLoc();
+    if (SpellLoc.isFileID())
+      break; // No inner macro.
+
+    // If spelling location resides in the same FileID as macro expansion
+    // location, it means there is no inner macro.
+    FileID MacroFID = SM.getFileID(Loc);
+    if (SM.isInFileID(SpellLoc, MacroFID))
+      break;
+
+    // Argument came from inner macro.
+    Loc = SpellLoc;
+  }
+
+  // Find the spelling location of the start of the non-argument expansion
+  // range. This is where the macro name was spelled in order to begin
+  // expanding this macro.
+  Loc = SM.getSpellingLoc(Loc);
+
+  // Dig out the buffer where the macro name was spelled and the extents of the
+  // name so that we can render it into the expansion note.
+  std::pair<FileID, unsigned> ExpansionInfo = SM.getDecomposedLoc(Loc);
+  unsigned MacroTokenLength = Lexer::MeasureTokenLength(Loc, SM, LangOpts);
+  StringRef ExpansionBuffer = SM.getBufferData(ExpansionInfo.first);
+  return ExpansionBuffer.substr(ExpansionInfo.second, MacroTokenLength);
+}
+
+//===----------------------------------------------------------------------===//
+// Character information.
+//===----------------------------------------------------------------------===//
+
+enum {
+  CHAR_HORZ_WS  = 0x01,  // ' ', '\t', '\f', '\v'.  Note, no '\0'
+  CHAR_VERT_WS  = 0x02,  // '\r', '\n'
+  CHAR_LETTER   = 0x04,  // a-z,A-Z
+  CHAR_NUMBER   = 0x08,  // 0-9
+  CHAR_UNDER    = 0x10,  // _
+  CHAR_PERIOD   = 0x20,  // .
+  CHAR_RAWDEL   = 0x40   // {}[]#<>%:;?*+-/^&|~!=,"'
+};
+
+// Statically initialize CharInfo table based on ASCII character set
+// Reference: FreeBSD 7.2 /usr/share/misc/ascii
+static const unsigned char CharInfo[256] =
+{
+// 0 NUL         1 SOH         2 STX         3 ETX
+// 4 EOT         5 ENQ         6 ACK         7 BEL
+   0           , 0           , 0           , 0           ,
+   0           , 0           , 0           , 0           ,
+// 8 BS          9 HT         10 NL         11 VT
+//12 NP         13 CR         14 SO         15 SI
+   0           , CHAR_HORZ_WS, CHAR_VERT_WS, CHAR_HORZ_WS,
+   CHAR_HORZ_WS, CHAR_VERT_WS, 0           , 0           ,
+//16 DLE        17 DC1        18 DC2        19 DC3
+//20 DC4        21 NAK        22 SYN        23 ETB
+   0           , 0           , 0           , 0           ,
+   0           , 0           , 0           , 0           ,
+//24 CAN        25 EM         26 SUB        27 ESC
+//28 FS         29 GS         30 RS         31 US
+   0           , 0           , 0           , 0           ,
+   0           , 0           , 0           , 0           ,
+//32 SP         33  !         34  "         35  #
+//36  $         37  %         38  &         39  '
+   CHAR_HORZ_WS, CHAR_RAWDEL , CHAR_RAWDEL , CHAR_RAWDEL ,
+   0           , CHAR_RAWDEL , CHAR_RAWDEL , CHAR_RAWDEL ,
+//40  (         41  )         42  *         43  +
+//44  ,         45  -         46  .         47  /
+   0           , 0           , CHAR_RAWDEL , CHAR_RAWDEL ,
+   CHAR_RAWDEL , CHAR_RAWDEL , CHAR_PERIOD , CHAR_RAWDEL ,
+//48  0         49  1         50  2         51  3
+//52  4         53  5         54  6         55  7
+   CHAR_NUMBER , CHAR_NUMBER , CHAR_NUMBER , CHAR_NUMBER ,
+   CHAR_NUMBER , CHAR_NUMBER , CHAR_NUMBER , CHAR_NUMBER ,
+//56  8         57  9         58  :         59  ;
+//60  <         61  =         62  >         63  ?
+   CHAR_NUMBER , CHAR_NUMBER , CHAR_RAWDEL , CHAR_RAWDEL ,
+   CHAR_RAWDEL , CHAR_RAWDEL , CHAR_RAWDEL , CHAR_RAWDEL ,
+//64  @         65  A         66  B         67  C
+//68  D         69  E         70  F         71  G
+   0           , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
+//72  H         73  I         74  J         75  K
+//76  L         77  M         78  N         79  O
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
+//80  P         81  Q         82  R         83  S
+//84  T         85  U         86  V         87  W
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
+//88  X         89  Y         90  Z         91  [
+//92  \         93  ]         94  ^         95  _
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_RAWDEL ,
+   0           , CHAR_RAWDEL , CHAR_RAWDEL , CHAR_UNDER  ,
+//96  `         97  a         98  b         99  c
+//100  d       101  e        102  f        103  g
+   0           , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
+//104  h       105  i        106  j        107  k
+//108  l       109  m        110  n        111  o
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
+//112  p       113  q        114  r        115  s
+//116  t       117  u        118  v        119  w
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_LETTER ,
+//120  x       121  y        122  z        123  {
+//124  |       125  }        126  ~        127 DEL
+   CHAR_LETTER , CHAR_LETTER , CHAR_LETTER , CHAR_RAWDEL ,
+   CHAR_RAWDEL , CHAR_RAWDEL , CHAR_RAWDEL , 0
+};
+
+static void InitCharacterInfo() {
+  static bool isInited = false;
+  if (isInited) return;
+  // check the statically-initialized CharInfo table
+  assert(CHAR_HORZ_WS == CharInfo[(int)' ']);
+  assert(CHAR_HORZ_WS == CharInfo[(int)'\t']);
+  assert(CHAR_HORZ_WS == CharInfo[(int)'\f']);
+  assert(CHAR_HORZ_WS == CharInfo[(int)'\v']);
+  assert(CHAR_VERT_WS == CharInfo[(int)'\n']);
+  assert(CHAR_VERT_WS == CharInfo[(int)'\r']);
+  assert(CHAR_UNDER   == CharInfo[(int)'_']);
+  assert(CHAR_PERIOD  == CharInfo[(int)'.']);
+  for (unsigned i = 'a'; i <= 'z'; ++i) {
+    assert(CHAR_LETTER == CharInfo[i]);
+    assert(CHAR_LETTER == CharInfo[i+'A'-'a']);
+  }
+  for (unsigned i = '0'; i <= '9'; ++i)
+    assert(CHAR_NUMBER == CharInfo[i]);
+    
+  isInited = true;
+}
+
+
+/// isIdentifierHead - Return true if this is the first character of an
+/// identifier, which is [a-zA-Z_].
+static inline bool isIdentifierHead(unsigned char c) {
+  return (CharInfo[c] & (CHAR_LETTER|CHAR_UNDER)) ? true : false;
+}
+
+/// isIdentifierBody - Return true if this is the body character of an
+/// identifier, which is [a-zA-Z0-9_].
+static inline bool isIdentifierBody(unsigned char c) {
+  return (CharInfo[c] & (CHAR_LETTER|CHAR_NUMBER|CHAR_UNDER)) ? true : false;
+}
+
+/// isHorizontalWhitespace - Return true if this character is horizontal
+/// whitespace: ' ', '\t', '\f', '\v'.  Note that this returns false for '\0'.
+static inline bool isHorizontalWhitespace(unsigned char c) {
+  return (CharInfo[c] & CHAR_HORZ_WS) ? true : false;
+}
+
+/// isVerticalWhitespace - Return true if this character is vertical
+/// whitespace: '\n', '\r'.  Note that this returns false for '\0'.
+static inline bool isVerticalWhitespace(unsigned char c) {
+  return (CharInfo[c] & CHAR_VERT_WS) ? true : false;
+}
+
+/// isWhitespace - Return true if this character is horizontal or vertical
+/// whitespace: ' ', '\t', '\f', '\v', '\n', '\r'.  Note that this returns false
+/// for '\0'.
+static inline bool isWhitespace(unsigned char c) {
+  return (CharInfo[c] & (CHAR_HORZ_WS|CHAR_VERT_WS)) ? true : false;
+}
+
+/// isNumberBody - Return true if this is the body character of an
+/// preprocessing number, which is [a-zA-Z0-9_.].
+static inline bool isNumberBody(unsigned char c) {
+  return (CharInfo[c] & (CHAR_LETTER|CHAR_NUMBER|CHAR_UNDER|CHAR_PERIOD)) ?
+    true : false;
+}
+
+/// isRawStringDelimBody - Return true if this is the body character of a
+/// raw string delimiter.
+static inline bool isRawStringDelimBody(unsigned char c) {
+  return (CharInfo[c] &
+          (CHAR_LETTER|CHAR_NUMBER|CHAR_UNDER|CHAR_PERIOD|CHAR_RAWDEL)) ?
+    true : false;
+}
+
+
+//===----------------------------------------------------------------------===//
+// Diagnostics forwarding code.
+//===----------------------------------------------------------------------===//
+
+/// GetMappedTokenLoc - If lexing out of a 'mapped buffer', where we pretend the
+/// lexer buffer was all expanded at a single point, perform the mapping.
+/// This is currently only used for _Pragma implementation, so it is the slow
+/// path of the hot getSourceLocation method.  Do not allow it to be inlined.
+static LLVM_ATTRIBUTE_NOINLINE SourceLocation GetMappedTokenLoc(
+    Preprocessor &PP, SourceLocation FileLoc, unsigned CharNo, unsigned TokLen);
+static SourceLocation GetMappedTokenLoc(Preprocessor &PP,
+                                        SourceLocation FileLoc,
+                                        unsigned CharNo, unsigned TokLen) {
+  assert(FileLoc.isMacroID() && "Must be a macro expansion");
+
+  // Otherwise, we're lexing "mapped tokens".  This is used for things like
+  // _Pragma handling.  Combine the expansion location of FileLoc with the
+  // spelling location.
+  SourceManager &SM = PP.getSourceManager();
+
+  // Create a new SLoc which is expanded from Expansion(FileLoc) but whose
+  // characters come from spelling(FileLoc)+Offset.
+  SourceLocation SpellingLoc = SM.getSpellingLoc(FileLoc);
+  SpellingLoc = SpellingLoc.getLocWithOffset(CharNo);
+
+  // Figure out the expansion loc range, which is the range covered by the
+  // original _Pragma(...) sequence.
+  std::pair<SourceLocation,SourceLocation> II =
+    SM.getImmediateExpansionRange(FileLoc);
+
+  return SM.createExpansionLoc(SpellingLoc, II.first, II.second, TokLen);
+}
+
+/// getSourceLocation - Return a source location identifier for the specified
+/// offset in the current file.
+SourceLocation Lexer::getSourceLocation(const char *Loc,
+                                        unsigned TokLen) const {
+  assert(Loc >= BufferStart && Loc <= BufferEnd &&
+         "Location out of range for this buffer!");
+
+  // In the normal case, we're just lexing from a simple file buffer, return
+  // the file id from FileLoc with the offset specified.
+  unsigned CharNo = Loc-BufferStart;
+  if (FileLoc.isFileID())
+    return FileLoc.getLocWithOffset(CharNo);
+
+  // Otherwise, this is the _Pragma lexer case, which pretends that all of the
+  // tokens are lexed from where the _Pragma was defined.
+  assert(PP && "This doesn't work on raw lexers");
+  return GetMappedTokenLoc(*PP, FileLoc, CharNo, TokLen);
+}
+
+/// Diag - Forwarding function for diagnostics.  This translate a source
+/// position in the current buffer into a SourceLocation object for rendering.
+DiagnosticBuilder Lexer::Diag(const char *Loc, unsigned DiagID) const {
+  return PP->Diag(getSourceLocation(Loc), DiagID);
+}
+
+//===----------------------------------------------------------------------===//
+// Trigraph and Escaped Newline Handling Code.
+//===----------------------------------------------------------------------===//
+
+/// GetTrigraphCharForLetter - Given a character that occurs after a ?? pair,
+/// return the decoded trigraph letter it corresponds to, or '\0' if nothing.
+static char GetTrigraphCharForLetter(char Letter) {
+  switch (Letter) {
+  default:   return 0;
+  case '=':  return '#';
+  case ')':  return ']';
+  case '(':  return '[';
+  case '!':  return '|';
+  case '\'': return '^';
+  case '>':  return '}';
+  case '/':  return '\\';
+  case '<':  return '{';
+  case '-':  return '~';
+  }
+}
+
+/// DecodeTrigraphChar - If the specified character is a legal trigraph when
+/// prefixed with ??, emit a trigraph warning.  If trigraphs are enabled,
+/// return the result character.  Finally, emit a warning about trigraph use
+/// whether trigraphs are enabled or not.
+static char DecodeTrigraphChar(const char *CP, Lexer *L) {
+  char Res = GetTrigraphCharForLetter(*CP);
+  if (!Res || !L) return Res;
+
+  if (!L->getLangOpts().Trigraphs) {
+    if (!L->isLexingRawMode())
+      L->Diag(CP-2, diag::trigraph_ignored);
+    return 0;
+  }
+
+  if (!L->isLexingRawMode())
+    L->Diag(CP-2, diag::trigraph_converted) << StringRef(&Res, 1);
+  return Res;
+}
+
+/// getEscapedNewLineSize - Return the size of the specified escaped newline,
+/// or 0 if it is not an escaped newline. P[-1] is known to be a "\" or a
+/// trigraph equivalent on entry to this function.
+unsigned Lexer::getEscapedNewLineSize(const char *Ptr) {
+  unsigned Size = 0;
+  while (isWhitespace(Ptr[Size])) {
+    ++Size;
+
+    if (Ptr[Size-1] != '\n' && Ptr[Size-1] != '\r')
+      continue;
+
+    // If this is a \r\n or \n\r, skip the other half.
+    if ((Ptr[Size] == '\r' || Ptr[Size] == '\n') &&
+        Ptr[Size-1] != Ptr[Size])
+      ++Size;
+
+    return Size;
+  }
+
+  // Not an escaped newline, must be a \t or something else.
+  return 0;
+}
+
+/// SkipEscapedNewLines - If P points to an escaped newline (or a series of
+/// them), skip over them and return the first non-escaped-newline found,
+/// otherwise return P.
+const char *Lexer::SkipEscapedNewLines(const char *P) {
+  while (1) {
+    const char *AfterEscape;
+    if (*P == '\\') {
+      AfterEscape = P+1;
+    } else if (*P == '?') {
+      // If not a trigraph for escape, bail out.
+      if (P[1] != '?' || P[2] != '/')
+        return P;
+      AfterEscape = P+3;
+    } else {
+      return P;
+    }
+
+    unsigned NewLineSize = Lexer::getEscapedNewLineSize(AfterEscape);
+    if (NewLineSize == 0) return P;
+    P = AfterEscape+NewLineSize;
+  }
+}
+
+/// \brief Checks that the given token is the first token that occurs after the
+/// given location (this excludes comments and whitespace). Returns the location
+/// immediately after the specified token. If the token is not found or the
+/// location is inside a macro, the returned source location will be invalid.
+SourceLocation Lexer::findLocationAfterToken(SourceLocation Loc,
+                                        tok::TokenKind TKind,
+                                        const SourceManager &SM,
+                                        const LangOptions &LangOpts,
+                                        bool SkipTrailingWhitespaceAndNewLine) {
+  if (Loc.isMacroID()) {
+    if (!Lexer::isAtEndOfMacroExpansion(Loc, SM, LangOpts, &Loc))
+      return SourceLocation();
+  }
+  Loc = Lexer::getLocForEndOfToken(Loc, 0, SM, LangOpts);
+
+  // Break down the source location.
+  std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(Loc);
+
+  // Try to load the file buffer.
+  bool InvalidTemp = false;
+  llvm::StringRef File = SM.getBufferData(LocInfo.first, &InvalidTemp);
+  if (InvalidTemp)
+    return SourceLocation();
+
+  const char *TokenBegin = File.data() + LocInfo.second;
+
+  // Lex from the start of the given location.
+  Lexer lexer(SM.getLocForStartOfFile(LocInfo.first), LangOpts, File.begin(),
+                                      TokenBegin, File.end());
+  // Find the token.
+  Token Tok;
+  lexer.LexFromRawLexer(Tok);
+  if (Tok.isNot(TKind))
+    return SourceLocation();
+  SourceLocation TokenLoc = Tok.getLocation();
+
+  // Calculate how much whitespace needs to be skipped if any.
+  unsigned NumWhitespaceChars = 0;
+  if (SkipTrailingWhitespaceAndNewLine) {
+    const char *TokenEnd = SM.getCharacterData(TokenLoc) +
+                           Tok.getLength();
+    unsigned char C = *TokenEnd;
+    while (isHorizontalWhitespace(C)) {
+      C = *(++TokenEnd);
+      NumWhitespaceChars++;
+    }
+    if (isVerticalWhitespace(C))
+      NumWhitespaceChars++;
+  }
+
+  return TokenLoc.getLocWithOffset(Tok.getLength() + NumWhitespaceChars);
+}
+
+/// getCharAndSizeSlow - Peek a single 'character' from the specified buffer,
+/// get its size, and return it.  This is tricky in several cases:
+///   1. If currently at the start of a trigraph, we warn about the trigraph,
+///      then either return the trigraph (skipping 3 chars) or the '?',
+///      depending on whether trigraphs are enabled or not.
+///   2. If this is an escaped newline (potentially with whitespace between
+///      the backslash and newline), implicitly skip the newline and return
+///      the char after it.
+///   3. If this is a UCN, return it.  FIXME: C++ UCN's?
+///
+/// This handles the slow/uncommon case of the getCharAndSize method.  Here we
+/// know that we can accumulate into Size, and that we have already incremented
+/// Ptr by Size bytes.
+///
+/// NOTE: When this method is updated, getCharAndSizeSlowNoWarn (below) should
+/// be updated to match.
+///
+char Lexer::getCharAndSizeSlow(const char *Ptr, unsigned &Size,
+                               Token *Tok) {
+  // If we have a slash, look for an escaped newline.
+  if (Ptr[0] == '\\') {
+    ++Size;
+    ++Ptr;
+Slash:
+    // Common case, backslash-char where the char is not whitespace.
+    if (!isWhitespace(Ptr[0])) return '\\';
+
+    // See if we have optional whitespace characters between the slash and
+    // newline.
+    if (unsigned EscapedNewLineSize = getEscapedNewLineSize(Ptr)) {
+      // Remember that this token needs to be cleaned.
+      if (Tok) Tok->setFlag(Token::NeedsCleaning);
+
+      // Warn if there was whitespace between the backslash and newline.
+      if (Ptr[0] != '\n' && Ptr[0] != '\r' && Tok && !isLexingRawMode())
+        Diag(Ptr, diag::backslash_newline_space);
+
+      // Found backslash<whitespace><newline>.  Parse the char after it.
+      Size += EscapedNewLineSize;
+      Ptr  += EscapedNewLineSize;
+
+      // If the char that we finally got was a \n, then we must have had
+      // something like \<newline><newline>.  We don't want to consume the
+      // second newline.
+      if (*Ptr == '\n' || *Ptr == '\r' || *Ptr == '\0')
+        return ' ';
+
+      // Use slow version to accumulate a correct size field.
+      return getCharAndSizeSlow(Ptr, Size, Tok);
+    }
+
+    // Otherwise, this is not an escaped newline, just return the slash.
+    return '\\';
+  }
+
+  // If this is a trigraph, process it.
+  if (Ptr[0] == '?' && Ptr[1] == '?') {
+    // If this is actually a legal trigraph (not something like "??x"), emit
+    // a trigraph warning.  If so, and if trigraphs are enabled, return it.
+    if (char C = DecodeTrigraphChar(Ptr+2, Tok ? this : 0)) {
+      // Remember that this token needs to be cleaned.
+      if (Tok) Tok->setFlag(Token::NeedsCleaning);
+
+      Ptr += 3;
+      Size += 3;
+      if (C == '\\') goto Slash;
+      return C;
+    }
+  }
+
+  // If this is neither, return a single character.
+  ++Size;
+  return *Ptr;
+}
+
+
+/// getCharAndSizeSlowNoWarn - Handle the slow/uncommon case of the
+/// getCharAndSizeNoWarn method.  Here we know that we can accumulate into Size,
+/// and that we have already incremented Ptr by Size bytes.
+///
+/// NOTE: When this method is updated, getCharAndSizeSlow (above) should
+/// be updated to match.
+char Lexer::getCharAndSizeSlowNoWarn(const char *Ptr, unsigned &Size,
+                                     const LangOptions &LangOpts) {
+  // If we have a slash, look for an escaped newline.
+  if (Ptr[0] == '\\') {
+    ++Size;
+    ++Ptr;
+Slash:
+    // Common case, backslash-char where the char is not whitespace.
+    if (!isWhitespace(Ptr[0])) return '\\';
+
+    // See if we have optional whitespace characters followed by a newline.
+    if (unsigned EscapedNewLineSize = getEscapedNewLineSize(Ptr)) {
+      // Found backslash<whitespace><newline>.  Parse the char after it.
+      Size += EscapedNewLineSize;
+      Ptr  += EscapedNewLineSize;
+
+      // If the char that we finally got was a \n, then we must have had
+      // something like \<newline><newline>.  We don't want to consume the
+      // second newline.
+      if (*Ptr == '\n' || *Ptr == '\r' || *Ptr == '\0')
+        return ' ';
+
+      // Use slow version to accumulate a correct size field.
+      return getCharAndSizeSlowNoWarn(Ptr, Size, LangOpts);
+    }
+
+    // Otherwise, this is not an escaped newline, just return the slash.
+    return '\\';
+  }
+
+  // If this is a trigraph, process it.
+  if (LangOpts.Trigraphs && Ptr[0] == '?' && Ptr[1] == '?') {
+    // If this is actually a legal trigraph (not something like "??x"), return
+    // it.
+    if (char C = GetTrigraphCharForLetter(Ptr[2])) {
+      Ptr += 3;
+      Size += 3;
+      if (C == '\\') goto Slash;
+      return C;
+    }
+  }
+
+  // If this is neither, return a single character.
+  ++Size;
+  return *Ptr;
+}
+
+//===----------------------------------------------------------------------===//
+// Helper methods for lexing.
+//===----------------------------------------------------------------------===//
+
+/// \brief Routine that indiscriminately skips bytes in the source file.
+void Lexer::SkipBytes(unsigned Bytes, bool StartOfLine) {
+  BufferPtr += Bytes;
+  if (BufferPtr > BufferEnd)
+    BufferPtr = BufferEnd;
+  IsAtStartOfLine = StartOfLine;
+}
+
+void Lexer::LexIdentifier(Token &Result, const char *CurPtr) {
+  // Match [_A-Za-z0-9]*, we have already matched [_A-Za-z$]
+  unsigned Size;
+  unsigned char C = *CurPtr++;
+  while (isIdentifierBody(C))
+    C = *CurPtr++;
+
+  --CurPtr;   // Back up over the skipped character.
+
+  // Fast path, no $,\,? in identifier found.  '\' might be an escaped newline
+  // or UCN, and ? might be a trigraph for '\', an escaped newline or UCN.
+  // FIXME: UCNs.
+  //
+  // TODO: Could merge these checks into a CharInfo flag to make the comparison
+  // cheaper
+  if (C != '\\' && C != '?' && (C != '$' || !LangOpts.DollarIdents)) {
+FinishIdentifier:
+    const char *IdStart = BufferPtr;
+    FormTokenWithChars(Result, CurPtr, tok::raw_identifier);
+    Result.setRawIdentifierData(IdStart);
+
+    // If we are in raw mode, return this identifier raw.  There is no need to
+    // look up identifier information or attempt to macro expand it.
+    if (LexingRawMode)
+      return;
+
+    // Fill in Result.IdentifierInfo and update the token kind,
+    // looking up the identifier in the identifier table.
+    IdentifierInfo *II = PP->LookUpIdentifierInfo(Result);
+
+    // Finally, now that we know we have an identifier, pass this off to the
+    // preprocessor, which may macro expand it or something.
+    if (II->isHandleIdentifierCase())
+      PP->HandleIdentifier(Result);
+    
+    return;
+  }
+
+  // Otherwise, $,\,? in identifier found.  Enter slower path.
+
+  C = getCharAndSize(CurPtr, Size);
+  while (1) {
+    if (C == '$') {
+      // If we hit a $ and they are not supported in identifiers, we are done.
+      if (!LangOpts.DollarIdents) goto FinishIdentifier;
+
+      // Otherwise, emit a diagnostic and continue.
+      if (!isLexingRawMode())
+        Diag(CurPtr, diag::ext_dollar_in_identifier);
+      CurPtr = ConsumeChar(CurPtr, Size, Result);
+      C = getCharAndSize(CurPtr, Size);
+      continue;
+    } else if (!isIdentifierBody(C)) { // FIXME: UCNs.
+      // Found end of identifier.
+      goto FinishIdentifier;
+    }
+
+    // Otherwise, this character is good, consume it.
+    CurPtr = ConsumeChar(CurPtr, Size, Result);
+
+    C = getCharAndSize(CurPtr, Size);
+    while (isIdentifierBody(C)) { // FIXME: UCNs.
+      CurPtr = ConsumeChar(CurPtr, Size, Result);
+      C = getCharAndSize(CurPtr, Size);
+    }
+  }
+}
+
+/// isHexaLiteral - Return true if Start points to a hex constant.
+/// in microsoft mode (where this is supposed to be several different tokens).
+static bool isHexaLiteral(const char *Start, const LangOptions &LangOpts) {
+  unsigned Size;
+  char C1 = Lexer::getCharAndSizeNoWarn(Start, Size, LangOpts);
+  if (C1 != '0')
+    return false;
+  char C2 = Lexer::getCharAndSizeNoWarn(Start + Size, Size, LangOpts);
+  return (C2 == 'x' || C2 == 'X');
+}
+
+/// LexNumericConstant - Lex the remainder of a integer or floating point
+/// constant. From[-1] is the first character lexed.  Return the end of the
+/// constant.
+void Lexer::LexNumericConstant(Token &Result, const char *CurPtr) {
+  unsigned Size;
+  char C = getCharAndSize(CurPtr, Size);
+  char PrevCh = 0;
+  while (isNumberBody(C)) { // FIXME: UCNs.
+    CurPtr = ConsumeChar(CurPtr, Size, Result);
+    PrevCh = C;
+    C = getCharAndSize(CurPtr, Size);
+  }
+
+  // If we fell out, check for a sign, due to 1e+12.  If we have one, continue.
+  if ((C == '-' || C == '+') && (PrevCh == 'E' || PrevCh == 'e')) {
+    // If we are in Microsoft mode, don't continue if the constant is hex.
+    // For example, MSVC will accept the following as 3 tokens: 0x1234567e+1
+    if (!LangOpts.MicrosoftExt || !isHexaLiteral(BufferPtr, LangOpts))
+      return LexNumericConstant(Result, ConsumeChar(CurPtr, Size, Result));
+  }
+
+  // If we have a hex FP constant, continue.
+  if ((C == '-' || C == '+') && (PrevCh == 'P' || PrevCh == 'p'))
+    return LexNumericConstant(Result, ConsumeChar(CurPtr, Size, Result));
+
+  // Update the location of token as well as BufferPtr.
+  const char *TokStart = BufferPtr;
+  FormTokenWithChars(Result, CurPtr, tok::numeric_constant);
+  Result.setLiteralData(TokStart);
+}
+
+/// LexUDSuffix - Lex the ud-suffix production for user-defined literal suffixes
+/// in C++11, or warn on a ud-suffix in C++98.
+const char *Lexer::LexUDSuffix(Token &Result, const char *CurPtr) {
+  assert(getLangOpts().CPlusPlus);
+
+  // Maximally munch an identifier. FIXME: UCNs.
+  unsigned Size;
+  char C = getCharAndSize(CurPtr, Size);
+  if (isIdentifierHead(C)) {
+    if (!getLangOpts().CPlusPlus0x) {
+      if (!isLexingRawMode())
+        Diag(CurPtr,
+             C == '_' ? diag::warn_cxx11_compat_user_defined_literal
+                      : diag::warn_cxx11_compat_reserved_user_defined_literal)
+          << FixItHint::CreateInsertion(getSourceLocation(CurPtr), " ");
+      return CurPtr;
+    }
+
+    // C++11 [lex.ext]p10, [usrlit.suffix]p1: A program containing a ud-suffix
+    // that does not start with an underscore is ill-formed. As a conforming
+    // extension, we treat all such suffixes as if they had whitespace before
+    // them.
+    if (C != '_') {
+      if (!isLexingRawMode())
+        Diag(CurPtr, getLangOpts().MicrosoftMode ? 
+            diag::ext_ms_reserved_user_defined_literal :
+            diag::ext_reserved_user_defined_literal)
+          << FixItHint::CreateInsertion(getSourceLocation(CurPtr), " ");
+      return CurPtr;
+    }
+
+    Result.setFlag(Token::HasUDSuffix);
+    do {
+      CurPtr = ConsumeChar(CurPtr, Size, Result);
+      C = getCharAndSize(CurPtr, Size);
+    } while (isIdentifierBody(C));
+  }
+  return CurPtr;
+}
+
+/// LexStringLiteral - Lex the remainder of a string literal, after having lexed
+/// either " or L" or u8" or u" or U".
+void Lexer::LexStringLiteral(Token &Result, const char *CurPtr,
+                             tok::TokenKind Kind) {
+  const char *NulCharacter = 0; // Does this string contain the \0 character?
+
+  if (!isLexingRawMode() &&
+      (Kind == tok::utf8_string_literal ||
+       Kind == tok::utf16_string_literal ||
+       Kind == tok::utf32_string_literal))
+    Diag(BufferPtr, diag::warn_cxx98_compat_unicode_literal);
+
+  char C = getAndAdvanceChar(CurPtr, Result);
+  while (C != '"') {
+    // Skip escaped characters.  Escaped newlines will already be processed by
+    // getAndAdvanceChar.
+    if (C == '\\')
+      C = getAndAdvanceChar(CurPtr, Result);
+    
+    if (C == '\n' || C == '\r' ||             // Newline.
+        (C == 0 && CurPtr-1 == BufferEnd)) {  // End of file.
+      if (!isLexingRawMode() && !LangOpts.AsmPreprocessor)
+        Diag(BufferPtr, diag::warn_unterminated_string);
+      FormTokenWithChars(Result, CurPtr-1, tok::unknown);
+      return;
+    }
+    
+    if (C == 0) {
+      if (isCodeCompletionPoint(CurPtr-1)) {
+        PP->CodeCompleteNaturalLanguage();
+        FormTokenWithChars(Result, CurPtr-1, tok::unknown);
+        return cutOffLexing();
+      }
+
+      NulCharacter = CurPtr-1;
+    }
+    C = getAndAdvanceChar(CurPtr, Result);
+  }
+
+  // If we are in C++11, lex the optional ud-suffix.
+  if (getLangOpts().CPlusPlus)
+    CurPtr = LexUDSuffix(Result, CurPtr);
+
+  // If a nul character existed in the string, warn about it.
+  if (NulCharacter && !isLexingRawMode())
+    Diag(NulCharacter, diag::null_in_string);
+
+  // Update the location of the token as well as the BufferPtr instance var.
+  const char *TokStart = BufferPtr;
+  FormTokenWithChars(Result, CurPtr, Kind);
+  Result.setLiteralData(TokStart);
+}
+
+/// LexRawStringLiteral - Lex the remainder of a raw string literal, after
+/// having lexed R", LR", u8R", uR", or UR".
+void Lexer::LexRawStringLiteral(Token &Result, const char *CurPtr,
+                                tok::TokenKind Kind) {
+  // This function doesn't use getAndAdvanceChar because C++0x [lex.pptoken]p3:
+  //  Between the initial and final double quote characters of the raw string,
+  //  any transformations performed in phases 1 and 2 (trigraphs,
+  //  universal-character-names, and line splicing) are reverted.
+
+  if (!isLexingRawMode())
+    Diag(BufferPtr, diag::warn_cxx98_compat_raw_string_literal);
+
+  unsigned PrefixLen = 0;
+
+  while (PrefixLen != 16 && isRawStringDelimBody(CurPtr[PrefixLen]))
+    ++PrefixLen;
+
+  // If the last character was not a '(', then we didn't lex a valid delimiter.
+  if (CurPtr[PrefixLen] != '(') {
+    if (!isLexingRawMode()) {
+      const char *PrefixEnd = &CurPtr[PrefixLen];
+      if (PrefixLen == 16) {
+        Diag(PrefixEnd, diag::err_raw_delim_too_long);
+      } else {
+        Diag(PrefixEnd, diag::err_invalid_char_raw_delim)
+          << StringRef(PrefixEnd, 1);
+      }
+    }
+
+    // Search for the next '"' in hopes of salvaging the lexer. Unfortunately,
+    // it's possible the '"' was intended to be part of the raw string, but
+    // there's not much we can do about that.
+    while (1) {
+      char C = *CurPtr++;
+
+      if (C == '"')
+        break;
+      if (C == 0 && CurPtr-1 == BufferEnd) {
+        --CurPtr;
+        break;
+      }
+    }
+
+    FormTokenWithChars(Result, CurPtr, tok::unknown);
+    return;
+  }
+
+  // Save prefix and move CurPtr past it
+  const char *Prefix = CurPtr;
+  CurPtr += PrefixLen + 1; // skip over prefix and '('
+
+  while (1) {
+    char C = *CurPtr++;
+
+    if (C == ')') {
+      // Check for prefix match and closing quote.
+      if (strncmp(CurPtr, Prefix, PrefixLen) == 0 && CurPtr[PrefixLen] == '"') {
+        CurPtr += PrefixLen + 1; // skip over prefix and '"'
+        break;
+      }
+    } else if (C == 0 && CurPtr-1 == BufferEnd) { // End of file.
+      if (!isLexingRawMode())
+        Diag(BufferPtr, diag::err_unterminated_raw_string)
+          << StringRef(Prefix, PrefixLen);
+      FormTokenWithChars(Result, CurPtr-1, tok::unknown);
+      return;
+    }
+  }
+
+  // If we are in C++11, lex the optional ud-suffix.
+  if (getLangOpts().CPlusPlus)
+    CurPtr = LexUDSuffix(Result, CurPtr);
+
+  // Update the location of token as well as BufferPtr.
+  const char *TokStart = BufferPtr;
+  FormTokenWithChars(Result, CurPtr, Kind);
+  Result.setLiteralData(TokStart);
+}
+
+/// LexAngledStringLiteral - Lex the remainder of an angled string literal,
+/// after having lexed the '<' character.  This is used for #include filenames.
+void Lexer::LexAngledStringLiteral(Token &Result, const char *CurPtr) {
+  const char *NulCharacter = 0; // Does this string contain the \0 character?
+  const char *AfterLessPos = CurPtr;
+  char C = getAndAdvanceChar(CurPtr, Result);
+  while (C != '>') {
+    // Skip escaped characters.
+    if (C == '\\') {
+      // Skip the escaped character.
+      C = getAndAdvanceChar(CurPtr, Result);
+    } else if (C == '\n' || C == '\r' ||             // Newline.
+               (C == 0 && (CurPtr-1 == BufferEnd ||  // End of file.
+                           isCodeCompletionPoint(CurPtr-1)))) {
+      // If the filename is unterminated, then it must just be a lone <
+      // character.  Return this as such.
+      FormTokenWithChars(Result, AfterLessPos, tok::less);
+      return;
+    } else if (C == 0) {
+      NulCharacter = CurPtr-1;
+    }
+    C = getAndAdvanceChar(CurPtr, Result);
+  }
+
+  // If a nul character existed in the string, warn about it.
+  if (NulCharacter && !isLexingRawMode())
+    Diag(NulCharacter, diag::null_in_string);
+
+  // Update the location of token as well as BufferPtr.
+  const char *TokStart = BufferPtr;
+  FormTokenWithChars(Result, CurPtr, tok::angle_string_literal);
+  Result.setLiteralData(TokStart);
+}
+
+
+/// LexCharConstant - Lex the remainder of a character constant, after having
+/// lexed either ' or L' or u' or U'.
+void Lexer::LexCharConstant(Token &Result, const char *CurPtr,
+                            tok::TokenKind Kind) {
+  const char *NulCharacter = 0; // Does this character contain the \0 character?
+
+  if (!isLexingRawMode() &&
+      (Kind == tok::utf16_char_constant || Kind == tok::utf32_char_constant))
+    Diag(BufferPtr, diag::warn_cxx98_compat_unicode_literal);
+
+  char C = getAndAdvanceChar(CurPtr, Result);
+  if (C == '\'') {
+    if (!isLexingRawMode() && !LangOpts.AsmPreprocessor)
+      Diag(BufferPtr, diag::err_empty_character);
+    FormTokenWithChars(Result, CurPtr, tok::unknown);
+    return;
+  }
+
+  while (C != '\'') {
+    // Skip escaped characters.
+    if (C == '\\') {
+      // Skip the escaped character.
+      // FIXME: UCN's
+      C = getAndAdvanceChar(CurPtr, Result);
+    } else if (C == '\n' || C == '\r' ||             // Newline.
+               (C == 0 && CurPtr-1 == BufferEnd)) {  // End of file.
+      if (!isLexingRawMode() && !LangOpts.AsmPreprocessor)
+        Diag(BufferPtr, diag::warn_unterminated_char);
+      FormTokenWithChars(Result, CurPtr-1, tok::unknown);
+      return;
+    } else if (C == 0) {
+      if (isCodeCompletionPoint(CurPtr-1)) {
+        PP->CodeCompleteNaturalLanguage();
+        FormTokenWithChars(Result, CurPtr-1, tok::unknown);
+        return cutOffLexing();
+      }
+
+      NulCharacter = CurPtr-1;
+    }
+    C = getAndAdvanceChar(CurPtr, Result);
+  }
+
+  // If we are in C++11, lex the optional ud-suffix.
+  if (getLangOpts().CPlusPlus)
+    CurPtr = LexUDSuffix(Result, CurPtr);
+
+  // If a nul character existed in the character, warn about it.
+  if (NulCharacter && !isLexingRawMode())
+    Diag(NulCharacter, diag::null_in_char);
+
+  // Update the location of token as well as BufferPtr.
+  const char *TokStart = BufferPtr;
+  FormTokenWithChars(Result, CurPtr, Kind);
+  Result.setLiteralData(TokStart);
+}
+
+/// SkipWhitespace - Efficiently skip over a series of whitespace characters.
+/// Update BufferPtr to point to the next non-whitespace character and return.
+///
+/// This method forms a token and returns true if KeepWhitespaceMode is enabled.
+///
+bool Lexer::SkipWhitespace(Token &Result, const char *CurPtr) {
+  // Whitespace - Skip it, then return the token after the whitespace.
+  unsigned char Char = *CurPtr;  // Skip consequtive spaces efficiently.
+  while (1) {
+    // Skip horizontal whitespace very aggressively.
+    while (isHorizontalWhitespace(Char))
+      Char = *++CurPtr;
+
+    // Otherwise if we have something other than whitespace, we're done.
+    if (Char != '\n' && Char != '\r')
+      break;
+
+    if (ParsingPreprocessorDirective) {
+      // End of preprocessor directive line, let LexTokenInternal handle this.
+      BufferPtr = CurPtr;
+      return false;
+    }
+
+    // ok, but handle newline.
+    // The returned token is at the start of the line.
+    Result.setFlag(Token::StartOfLine);
+    // No leading whitespace seen so far.
+    Result.clearFlag(Token::LeadingSpace);
+    Char = *++CurPtr;
+  }
+
+  // If this isn't immediately after a newline, there is leading space.
+  char PrevChar = CurPtr[-1];
+  if (PrevChar != '\n' && PrevChar != '\r')
+    Result.setFlag(Token::LeadingSpace);
+
+  // If the client wants us to return whitespace, return it now.
+  if (isKeepWhitespaceMode()) {
+    FormTokenWithChars(Result, CurPtr, tok::unknown);
+    return true;
+  }
+
+  BufferPtr = CurPtr;
+  return false;
+}
+
+// SkipBCPLComment - We have just read the // characters from input.  Skip until
+// we find the newline character thats terminate the comment.  Then update
+/// BufferPtr and return.
+///
+/// If we're in KeepCommentMode or any CommentHandler has inserted
+/// some tokens, this will store the first token and return true.
+bool Lexer::SkipBCPLComment(Token &Result, const char *CurPtr) {
+  // If BCPL comments aren't explicitly enabled for this language, emit an
+  // extension warning.
+  if (!LangOpts.BCPLComment && !isLexingRawMode()) {
+    Diag(BufferPtr, diag::ext_bcpl_comment);
+
+    // Mark them enabled so we only emit one warning for this translation
+    // unit.
+    LangOpts.BCPLComment = true;
+  }
+
+  // Scan over the body of the comment.  The common case, when scanning, is that
+  // the comment contains normal ascii characters with nothing interesting in
+  // them.  As such, optimize for this case with the inner loop.
+  char C;
+  do {
+    C = *CurPtr;
+    // Skip over characters in the fast loop.
+    while (C != 0 &&                // Potentially EOF.
+           C != '\n' && C != '\r')  // Newline or DOS-style newline.
+      C = *++CurPtr;
+
+    const char *NextLine = CurPtr;
+    if (C != 0) {
+      // We found a newline, see if it's escaped.
+      const char *EscapePtr = CurPtr-1;
+      while (isHorizontalWhitespace(*EscapePtr)) // Skip whitespace.
+        --EscapePtr;
+
+      if (*EscapePtr == '\\') // Escaped newline.
+        CurPtr = EscapePtr;
+      else if (EscapePtr[0] == '/' && EscapePtr[-1] == '?' &&
+               EscapePtr[-2] == '?') // Trigraph-escaped newline.
+        CurPtr = EscapePtr-2;
+      else
+        break; // This is a newline, we're done.
+
+      C = *CurPtr;
+    }
+
+    // Otherwise, this is a hard case.  Fall back on getAndAdvanceChar to
+    // properly decode the character.  Read it in raw mode to avoid emitting
+    // diagnostics about things like trigraphs.  If we see an escaped newline,
+    // we'll handle it below.
+    const char *OldPtr = CurPtr;
+    bool OldRawMode = isLexingRawMode();
+    LexingRawMode = true;
+    C = getAndAdvanceChar(CurPtr, Result);
+    LexingRawMode = OldRawMode;
+
+    // If we only read only one character, then no special handling is needed.
+    // We're done and can skip forward to the newline.
+    if (C != 0 && CurPtr == OldPtr+1) {
+      CurPtr = NextLine;
+      break;
+    }
+
+    // If we read multiple characters, and one of those characters was a \r or
+    // \n, then we had an escaped newline within the comment.  Emit diagnostic
+    // unless the next line is also a // comment.
+    if (CurPtr != OldPtr+1 && C != '/' && CurPtr[0] != '/') {
+      for (; OldPtr != CurPtr; ++OldPtr)
+        if (OldPtr[0] == '\n' || OldPtr[0] == '\r') {
+          // Okay, we found a // comment that ends in a newline, if the next
+          // line is also a // comment, but has spaces, don't emit a diagnostic.
+          if (isWhitespace(C)) {
+            const char *ForwardPtr = CurPtr;
+            while (isWhitespace(*ForwardPtr))  // Skip whitespace.
+              ++ForwardPtr;
+            if (ForwardPtr[0] == '/' && ForwardPtr[1] == '/')
+              break;
+          }
+
+          if (!isLexingRawMode())
+            Diag(OldPtr-1, diag::ext_multi_line_bcpl_comment);
+          break;
+        }
+    }
+
+    if (CurPtr == BufferEnd+1) { 
+      --CurPtr; 
+      break; 
+    }
+
+    if (C == '\0' && isCodeCompletionPoint(CurPtr-1)) {
+      PP->CodeCompleteNaturalLanguage();
+      cutOffLexing();
+      return false;
+    }
+
+  } while (C != '\n' && C != '\r');
+
+  // Found but did not consume the newline.  Notify comment handlers about the
+  // comment unless we're in a #if 0 block.
+  if (PP && !isLexingRawMode() &&
+      PP->HandleComment(Result, SourceRange(getSourceLocation(BufferPtr),
+                                            getSourceLocation(CurPtr)))) {
+    BufferPtr = CurPtr;
+    return true; // A token has to be returned.
+  }
+
+  // If we are returning comments as tokens, return this comment as a token.
+  if (inKeepCommentMode())
+    return SaveBCPLComment(Result, CurPtr);
+
+  // If we are inside a preprocessor directive and we see the end of line,
+  // return immediately, so that the lexer can return this as an EOD token.
+  if (ParsingPreprocessorDirective || CurPtr == BufferEnd) {
+    BufferPtr = CurPtr;
+    return false;
+  }
+
+  // Otherwise, eat the \n character.  We don't care if this is a \n\r or
+  // \r\n sequence.  This is an efficiency hack (because we know the \n can't
+  // contribute to another token), it isn't needed for correctness.  Note that
+  // this is ok even in KeepWhitespaceMode, because we would have returned the
+  /// comment above in that mode.
+  ++CurPtr;
+
+  // The next returned token is at the start of the line.
+  Result.setFlag(Token::StartOfLine);
+  // No leading whitespace seen so far.
+  Result.clearFlag(Token::LeadingSpace);
+  BufferPtr = CurPtr;
+  return false;
+}
+
+/// SaveBCPLComment - If in save-comment mode, package up this BCPL comment in
+/// an appropriate way and return it.
+bool Lexer::SaveBCPLComment(Token &Result, const char *CurPtr) {
+  // If we're not in a preprocessor directive, just return the // comment
+  // directly.
+  FormTokenWithChars(Result, CurPtr, tok::comment);
+
+  if (!ParsingPreprocessorDirective)
+    return true;
+
+  // If this BCPL-style comment is in a macro definition, transmogrify it into
+  // a C-style block comment.
+  bool Invalid = false;
+  std::string Spelling = PP->getSpelling(Result, &Invalid);
+  if (Invalid)
+    return true;
+  
+  assert(Spelling[0] == '/' && Spelling[1] == '/' && "Not bcpl comment?");
+  Spelling[1] = '*';   // Change prefix to "/*".
+  Spelling += "*/";    // add suffix.
+
+  Result.setKind(tok::comment);
+  PP->CreateString(&Spelling[0], Spelling.size(), Result,
+                   Result.getLocation(), Result.getLocation());
+  return true;
+}
+
+/// isBlockCommentEndOfEscapedNewLine - Return true if the specified newline
+/// character (either \n or \r) is part of an escaped newline sequence.  Issue a
+/// diagnostic if so.  We know that the newline is inside of a block comment.
+static bool isEndOfBlockCommentWithEscapedNewLine(const char *CurPtr,
+                                                  Lexer *L) {
+  assert(CurPtr[0] == '\n' || CurPtr[0] == '\r');
+
+  // Back up off the newline.
+  --CurPtr;
+
+  // If this is a two-character newline sequence, skip the other character.
+  if (CurPtr[0] == '\n' || CurPtr[0] == '\r') {
+    // \n\n or \r\r -> not escaped newline.
+    if (CurPtr[0] == CurPtr[1])
+      return false;
+    // \n\r or \r\n -> skip the newline.
+    --CurPtr;
+  }
+
+  // If we have horizontal whitespace, skip over it.  We allow whitespace
+  // between the slash and newline.
+  bool HasSpace = false;
+  while (isHorizontalWhitespace(*CurPtr) || *CurPtr == 0) {
+    --CurPtr;
+    HasSpace = true;
+  }
+
+  // If we have a slash, we know this is an escaped newline.
+  if (*CurPtr == '\\') {
+    if (CurPtr[-1] != '*') return false;
+  } else {
+    // It isn't a slash, is it the ?? / trigraph?
+    if (CurPtr[0] != '/' || CurPtr[-1] != '?' || CurPtr[-2] != '?' ||
+        CurPtr[-3] != '*')
+      return false;
+
+    // This is the trigraph ending the comment.  Emit a stern warning!
+    CurPtr -= 2;
+
+    // If no trigraphs are enabled, warn that we ignored this trigraph and
+    // ignore this * character.
+    if (!L->getLangOpts().Trigraphs) {
+      if (!L->isLexingRawMode())
+        L->Diag(CurPtr, diag::trigraph_ignored_block_comment);
+      return false;
+    }
+    if (!L->isLexingRawMode())
+      L->Diag(CurPtr, diag::trigraph_ends_block_comment);
+  }
+
+  // Warn about having an escaped newline between the */ characters.
+  if (!L->isLexingRawMode())
+    L->Diag(CurPtr, diag::escaped_newline_block_comment_end);
+
+  // If there was space between the backslash and newline, warn about it.
+  if (HasSpace && !L->isLexingRawMode())
+    L->Diag(CurPtr, diag::backslash_newline_space);
+
+  return true;
+}
+
+#ifdef __SSE2__
+#include <emmintrin.h>
+#elif __ALTIVEC__
+#include <altivec.h>
+#undef bool
+#endif
+
+/// SkipBlockComment - We have just read the /* characters from input.  Read
+/// until we find the */ characters that terminate the comment.  Note that we
+/// don't bother decoding trigraphs or escaped newlines in block comments,
+/// because they cannot cause the comment to end.  The only thing that can
+/// happen is the comment could end with an escaped newline between the */ end
+/// of comment.
+///
+/// If we're in KeepCommentMode or any CommentHandler has inserted
+/// some tokens, this will store the first token and return true.
+bool Lexer::SkipBlockComment(Token &Result, const char *CurPtr) {
+  // Scan one character past where we should, looking for a '/' character.  Once
+  // we find it, check to see if it was preceded by a *.  This common
+  // optimization helps people who like to put a lot of * characters in their
+  // comments.
+
+  // The first character we get with newlines and trigraphs skipped to handle
+  // the degenerate /*/ case below correctly if the * has an escaped newline
+  // after it.
+  unsigned CharSize;
+  unsigned char C = getCharAndSize(CurPtr, CharSize);
+  CurPtr += CharSize;
+  if (C == 0 && CurPtr == BufferEnd+1) {
+    if (!isLexingRawMode())
+      Diag(BufferPtr, diag::err_unterminated_block_comment);
+    --CurPtr;
+
+    // KeepWhitespaceMode should return this broken comment as a token.  Since
+    // it isn't a well formed comment, just return it as an 'unknown' token.
+    if (isKeepWhitespaceMode()) {
+      FormTokenWithChars(Result, CurPtr, tok::unknown);
+      return true;
+    }
+
+    BufferPtr = CurPtr;
+    return false;
+  }
+
+  // Check to see if the first character after the '/*' is another /.  If so,
+  // then this slash does not end the block comment, it is part of it.
+  if (C == '/')
+    C = *CurPtr++;
+
+  while (1) {
+    // Skip over all non-interesting characters until we find end of buffer or a
+    // (probably ending) '/' character.
+    if (CurPtr + 24 < BufferEnd &&
+        // If there is a code-completion point avoid the fast scan because it
+        // doesn't check for '\0'.
+        !(PP && PP->getCodeCompletionFileLoc() == FileLoc)) {
+      // While not aligned to a 16-byte boundary.
+      while (C != '/' && ((intptr_t)CurPtr & 0x0F) != 0)
+        C = *CurPtr++;
+
+      if (C == '/') goto FoundSlash;
+
+#ifdef __SSE2__
+      __m128i Slashes = _mm_set1_epi8('/');
+      while (CurPtr+16 <= BufferEnd) {
+        int cmp = _mm_movemask_epi8(_mm_cmpeq_epi8(*(__m128i*)CurPtr, Slashes));
+        if (cmp != 0) {
+          // Adjust the pointer to point directly after the first slash. It's
+          // not necessary to set C here, it will be overwritten at the end of
+          // the outer loop.
+          CurPtr += llvm::CountTrailingZeros_32(cmp) + 1;
+          goto FoundSlash;
+        }
+        CurPtr += 16;
+      }
+#elif __ALTIVEC__
+      __vector unsigned char Slashes = {
+        '/', '/', '/', '/',  '/', '/', '/', '/',
+        '/', '/', '/', '/',  '/', '/', '/', '/'
+      };
+      while (CurPtr+16 <= BufferEnd &&
+             !vec_any_eq(*(vector unsigned char*)CurPtr, Slashes))
+        CurPtr += 16;
+#else
+      // Scan for '/' quickly.  Many block comments are very large.
+      while (CurPtr[0] != '/' &&
+             CurPtr[1] != '/' &&
+             CurPtr[2] != '/' &&
+             CurPtr[3] != '/' &&
+             CurPtr+4 < BufferEnd) {
+        CurPtr += 4;
+      }
+#endif
+
+      // It has to be one of the bytes scanned, increment to it and read one.
+      C = *CurPtr++;
+    }
+
+    // Loop to scan the remainder.
+    while (C != '/' && C != '\0')
+      C = *CurPtr++;
+
+    if (C == '/') {
+  FoundSlash:
+      if (CurPtr[-2] == '*')  // We found the final */.  We're done!
+        break;
+
+      if ((CurPtr[-2] == '\n' || CurPtr[-2] == '\r')) {
+        if (isEndOfBlockCommentWithEscapedNewLine(CurPtr-2, this)) {
+          // We found the final */, though it had an escaped newline between the
+          // * and /.  We're done!
+          break;
+        }
+      }
+      if (CurPtr[0] == '*' && CurPtr[1] != '/') {
+        // If this is a /* inside of the comment, emit a warning.  Don't do this
+        // if this is a /*/, which will end the comment.  This misses cases with
+        // embedded escaped newlines, but oh well.
+        if (!isLexingRawMode())
+          Diag(CurPtr-1, diag::warn_nested_block_comment);
+      }
+    } else if (C == 0 && CurPtr == BufferEnd+1) {
+      if (!isLexingRawMode())
+        Diag(BufferPtr, diag::err_unterminated_block_comment);
+      // Note: the user probably forgot a */.  We could continue immediately
+      // after the /*, but this would involve lexing a lot of what really is the
+      // comment, which surely would confuse the parser.
+      --CurPtr;
+
+      // KeepWhitespaceMode should return this broken comment as a token.  Since
+      // it isn't a well formed comment, just return it as an 'unknown' token.
+      if (isKeepWhitespaceMode()) {
+        FormTokenWithChars(Result, CurPtr, tok::unknown);
+        return true;
+      }
+
+      BufferPtr = CurPtr;
+      return false;
+    } else if (C == '\0' && isCodeCompletionPoint(CurPtr-1)) {
+      PP->CodeCompleteNaturalLanguage();
+      cutOffLexing();
+      return false;
+    }
+
+    C = *CurPtr++;
+  }
+
+  // Notify comment handlers about the comment unless we're in a #if 0 block.
+  if (PP && !isLexingRawMode() &&
+      PP->HandleComment(Result, SourceRange(getSourceLocation(BufferPtr),
+                                            getSourceLocation(CurPtr)))) {
+    BufferPtr = CurPtr;
+    return true; // A token has to be returned.
+  }
+
+  // If we are returning comments as tokens, return this comment as a token.
+  if (inKeepCommentMode()) {
+    FormTokenWithChars(Result, CurPtr, tok::comment);
+    return true;
+  }
+
+  // It is common for the tokens immediately after a /**/ comment to be
+  // whitespace.  Instead of going through the big switch, handle it
+  // efficiently now.  This is safe even in KeepWhitespaceMode because we would
+  // have already returned above with the comment as a token.
+  if (isHorizontalWhitespace(*CurPtr)) {
+    Result.setFlag(Token::LeadingSpace);
+    SkipWhitespace(Result, CurPtr+1);
+    return false;
+  }
+
+  // Otherwise, just return so that the next character will be lexed as a token.
+  BufferPtr = CurPtr;
+  Result.setFlag(Token::LeadingSpace);
+  return false;
+}
+
+//===----------------------------------------------------------------------===//
+// Primary Lexing Entry Points
+//===----------------------------------------------------------------------===//
+
+/// ReadToEndOfLine - Read the rest of the current preprocessor line as an
+/// uninterpreted string.  This switches the lexer out of directive mode.
+std::string Lexer::ReadToEndOfLine() {
+  assert(ParsingPreprocessorDirective && ParsingFilename == false &&
+         "Must be in a preprocessing directive!");
+  std::string Result;
+  Token Tmp;
+
+  // CurPtr - Cache BufferPtr in an automatic variable.
+  const char *CurPtr = BufferPtr;
+  while (1) {
+    char Char = getAndAdvanceChar(CurPtr, Tmp);
+    switch (Char) {
+    default:
+      Result += Char;
+      break;
+    case 0:  // Null.
+      // Found end of file?
+      if (CurPtr-1 != BufferEnd) {
+        if (isCodeCompletionPoint(CurPtr-1)) {
+          PP->CodeCompleteNaturalLanguage();
+          cutOffLexing();
+          return Result;
+        }
+
+        // Nope, normal character, continue.
+        Result += Char;
+        break;
+      }
+      // FALL THROUGH.
+    case '\r':
+    case '\n':
+      // Okay, we found the end of the line. First, back up past the \0, \r, \n.
+      assert(CurPtr[-1] == Char && "Trigraphs for newline?");
+      BufferPtr = CurPtr-1;
+
+      // Next, lex the character, which should handle the EOD transition.
+      Lex(Tmp);
+      if (Tmp.is(tok::code_completion)) {
+        if (PP)
+          PP->CodeCompleteNaturalLanguage();
+        Lex(Tmp);
+      }
+      assert(Tmp.is(tok::eod) && "Unexpected token!");
+
+      // Finally, we're done, return the string we found.
+      return Result;
+    }
+  }
+}
+
+/// LexEndOfFile - CurPtr points to the end of this file.  Handle this
+/// condition, reporting diagnostics and handling other edge cases as required.
+/// This returns true if Result contains a token, false if PP.Lex should be
+/// called again.
+bool Lexer::LexEndOfFile(Token &Result, const char *CurPtr) {
+  // If we hit the end of the file while parsing a preprocessor directive,
+  // end the preprocessor directive first.  The next token returned will
+  // then be the end of file.
+  if (ParsingPreprocessorDirective) {
+    // Done parsing the "line".
+    ParsingPreprocessorDirective = false;
+    // Update the location of token as well as BufferPtr.
+    FormTokenWithChars(Result, CurPtr, tok::eod);
+
+    // Restore comment saving mode, in case it was disabled for directive.
+    SetCommentRetentionState(PP->getCommentRetentionState());
+    return true;  // Have a token.
+  }
+ 
+  // If we are in raw mode, return this event as an EOF token.  Let the caller
+  // that put us in raw mode handle the event.
+  if (isLexingRawMode()) {
+    Result.startToken();
+    BufferPtr = BufferEnd;
+    FormTokenWithChars(Result, BufferEnd, tok::eof);
+    return true;
+  }
+  
+  // Issue diagnostics for unterminated #if and missing newline.
+
+  // If we are in a #if directive, emit an error.
+  while (!ConditionalStack.empty()) {
+    if (PP->getCodeCompletionFileLoc() != FileLoc)
+      PP->Diag(ConditionalStack.back().IfLoc,
+               diag::err_pp_unterminated_conditional);
+    ConditionalStack.pop_back();
+  }
+
+  // C99 5.1.1.2p2: If the file is non-empty and didn't end in a newline, issue
+  // a pedwarn.
+  if (CurPtr != BufferStart && (CurPtr[-1] != '\n' && CurPtr[-1] != '\r'))
+    Diag(BufferEnd, LangOpts.CPlusPlus0x ? // C++11 [lex.phases] 2.2 p2
+         diag::warn_cxx98_compat_no_newline_eof : diag::ext_no_newline_eof)
+    << FixItHint::CreateInsertion(getSourceLocation(BufferEnd), "\n");
+
+  BufferPtr = CurPtr;
+
+  // Finally, let the preprocessor handle this.
+  return PP->HandleEndOfFile(Result);
+}
+
+/// isNextPPTokenLParen - Return 1 if the next unexpanded token lexed from
+/// the specified lexer will return a tok::l_paren token, 0 if it is something
+/// else and 2 if there are no more tokens in the buffer controlled by the
+/// lexer.
+unsigned Lexer::isNextPPTokenLParen() {
+  assert(!LexingRawMode && "How can we expand a macro from a skipping buffer?");
+
+  // Switch to 'skipping' mode.  This will ensure that we can lex a token
+  // without emitting diagnostics, disables macro expansion, and will cause EOF
+  // to return an EOF token instead of popping the include stack.
+  LexingRawMode = true;
+
+  // Save state that can be changed while lexing so that we can restore it.
+  const char *TmpBufferPtr = BufferPtr;
+  bool inPPDirectiveMode = ParsingPreprocessorDirective;
+
+  Token Tok;
+  Tok.startToken();
+  LexTokenInternal(Tok);
+
+  // Restore state that may have changed.
+  BufferPtr = TmpBufferPtr;
+  ParsingPreprocessorDirective = inPPDirectiveMode;
+
+  // Restore the lexer back to non-skipping mode.
+  LexingRawMode = false;
+
+  if (Tok.is(tok::eof))
+    return 2;
+  return Tok.is(tok::l_paren);
+}
+
+/// FindConflictEnd - Find the end of a version control conflict marker.
+static const char *FindConflictEnd(const char *CurPtr, const char *BufferEnd,
+                                   ConflictMarkerKind CMK) {
+  const char *Terminator = CMK == CMK_Perforce ? "<<<<\n" : ">>>>>>>";
+  size_t TermLen = CMK == CMK_Perforce ? 5 : 7;
+  StringRef RestOfBuffer(CurPtr+TermLen, BufferEnd-CurPtr-TermLen);
+  size_t Pos = RestOfBuffer.find(Terminator);
+  while (Pos != StringRef::npos) {
+    // Must occur at start of line.
+    if (RestOfBuffer[Pos-1] != '\r' &&
+        RestOfBuffer[Pos-1] != '\n') {
+      RestOfBuffer = RestOfBuffer.substr(Pos+TermLen);
+      Pos = RestOfBuffer.find(Terminator);
+      continue;
+    }
+    return RestOfBuffer.data()+Pos;
+  }
+  return 0;
+}
+
+/// IsStartOfConflictMarker - If the specified pointer is the start of a version
+/// control conflict marker like '<<<<<<<', recognize it as such, emit an error
+/// and recover nicely.  This returns true if it is a conflict marker and false
+/// if not.
+bool Lexer::IsStartOfConflictMarker(const char *CurPtr) {
+  // Only a conflict marker if it starts at the beginning of a line.
+  if (CurPtr != BufferStart &&
+      CurPtr[-1] != '\n' && CurPtr[-1] != '\r')
+    return false;
+  
+  // Check to see if we have <<<<<<< or >>>>.
+  if ((BufferEnd-CurPtr < 8 || StringRef(CurPtr, 7) != "<<<<<<<") &&
+      (BufferEnd-CurPtr < 6 || StringRef(CurPtr, 5) != ">>>> "))
+    return false;
+
+  // If we have a situation where we don't care about conflict markers, ignore
+  // it.
+  if (CurrentConflictMarkerState || isLexingRawMode())
+    return false;
+  
+  ConflictMarkerKind Kind = *CurPtr == '<' ? CMK_Normal : CMK_Perforce;
+
+  // Check to see if there is an ending marker somewhere in the buffer at the
+  // start of a line to terminate this conflict marker.
+  if (FindConflictEnd(CurPtr, BufferEnd, Kind)) {
+    // We found a match.  We are really in a conflict marker.
+    // Diagnose this, and ignore to the end of line.
+    Diag(CurPtr, diag::err_conflict_marker);
+    CurrentConflictMarkerState = Kind;
+    
+    // Skip ahead to the end of line.  We know this exists because the
+    // end-of-conflict marker starts with \r or \n.
+    while (*CurPtr != '\r' && *CurPtr != '\n') {
+      assert(CurPtr != BufferEnd && "Didn't find end of line");
+      ++CurPtr;
+    }
+    BufferPtr = CurPtr;
+    return true;
+  }
+  
+  // No end of conflict marker found.
+  return false;
+}
+
+
+/// HandleEndOfConflictMarker - If this is a '====' or '||||' or '>>>>', or if
+/// it is '<<<<' and the conflict marker started with a '>>>>' marker, then it
+/// is the end of a conflict marker.  Handle it by ignoring up until the end of
+/// the line.  This returns true if it is a conflict marker and false if not.
+bool Lexer::HandleEndOfConflictMarker(const char *CurPtr) {
+  // Only a conflict marker if it starts at the beginning of a line.
+  if (CurPtr != BufferStart &&
+      CurPtr[-1] != '\n' && CurPtr[-1] != '\r')
+    return false;
+  
+  // If we have a situation where we don't care about conflict markers, ignore
+  // it.
+  if (!CurrentConflictMarkerState || isLexingRawMode())
+    return false;
+  
+  // Check to see if we have the marker (4 characters in a row).
+  for (unsigned i = 1; i != 4; ++i)
+    if (CurPtr[i] != CurPtr[0])
+      return false;
+  
+  // If we do have it, search for the end of the conflict marker.  This could
+  // fail if it got skipped with a '#if 0' or something.  Note that CurPtr might
+  // be the end of conflict marker.
+  if (const char *End = FindConflictEnd(CurPtr, BufferEnd,
+                                        CurrentConflictMarkerState)) {
+    CurPtr = End;
+    
+    // Skip ahead to the end of line.
+    while (CurPtr != BufferEnd && *CurPtr != '\r' && *CurPtr != '\n')
+      ++CurPtr;
+    
+    BufferPtr = CurPtr;
+    
+    // No longer in the conflict marker.
+    CurrentConflictMarkerState = CMK_None;
+    return true;
+  }
+  
+  return false;
+}
+
+bool Lexer::isCodeCompletionPoint(const char *CurPtr) const {
+  if (PP && PP->isCodeCompletionEnabled()) {
+    SourceLocation Loc = FileLoc.getLocWithOffset(CurPtr-BufferStart);
+    return Loc == PP->getCodeCompletionLoc();
+  }
+
+  return false;
+}
+
+
+/// LexTokenInternal - This implements a simple C family lexer.  It is an
+/// extremely performance critical piece of code.  This assumes that the buffer
+/// has a null character at the end of the file.  This returns a preprocessing
+/// token, not a normal token, as such, it is an internal interface.  It assumes
+/// that the Flags of result have been cleared before calling this.
+void Lexer::LexTokenInternal(Token &Result) {
+LexNextToken:
+  // New token, can't need cleaning yet.
+  Result.clearFlag(Token::NeedsCleaning);
+  Result.setIdentifierInfo(0);
+
+  // CurPtr - Cache BufferPtr in an automatic variable.
+  const char *CurPtr = BufferPtr;
+
+  // Small amounts of horizontal whitespace is very common between tokens.
+  if ((*CurPtr == ' ') || (*CurPtr == '\t')) {
+    ++CurPtr;
+    while ((*CurPtr == ' ') || (*CurPtr == '\t'))
+      ++CurPtr;
+
+    // If we are keeping whitespace and other tokens, just return what we just
+    // skipped.  The next lexer invocation will return the token after the
+    // whitespace.
+    if (isKeepWhitespaceMode()) {
+      FormTokenWithChars(Result, CurPtr, tok::unknown);
+      return;
+    }
+
+    BufferPtr = CurPtr;
+    Result.setFlag(Token::LeadingSpace);
+  }
+
+  unsigned SizeTmp, SizeTmp2;   // Temporaries for use in cases below.
+
+  // Read a character, advancing over it.
+  char Char = getAndAdvanceChar(CurPtr, Result);
+  tok::TokenKind Kind;
+
+  switch (Char) {
+  case 0:  // Null.
+    // Found end of file?
+    if (CurPtr-1 == BufferEnd) {
+      // Read the PP instance variable into an automatic variable, because
+      // LexEndOfFile will often delete 'this'.
+      Preprocessor *PPCache = PP;
+      if (LexEndOfFile(Result, CurPtr-1))  // Retreat back into the file.
+        return;   // Got a token to return.
+      assert(PPCache && "Raw buffer::LexEndOfFile should return a token");
+      return PPCache->Lex(Result);
+    }
+
+    // Check if we are performing code completion.
+    if (isCodeCompletionPoint(CurPtr-1)) {
+      // Return the code-completion token.
+      Result.startToken();
+      FormTokenWithChars(Result, CurPtr, tok::code_completion);
+      return;
+    }
+
+    if (!isLexingRawMode())
+      Diag(CurPtr-1, diag::null_in_file);
+    Result.setFlag(Token::LeadingSpace);
+    if (SkipWhitespace(Result, CurPtr))
+      return; // KeepWhitespaceMode
+
+    goto LexNextToken;   // GCC isn't tail call eliminating.
+      
+  case 26:  // DOS & CP/M EOF: "^Z".
+    // If we're in Microsoft extensions mode, treat this as end of file.
+    if (LangOpts.MicrosoftExt) {
+      // Read the PP instance variable into an automatic variable, because
+      // LexEndOfFile will often delete 'this'.
+      Preprocessor *PPCache = PP;
+      if (LexEndOfFile(Result, CurPtr-1))  // Retreat back into the file.
+        return;   // Got a token to return.
+      assert(PPCache && "Raw buffer::LexEndOfFile should return a token");
+      return PPCache->Lex(Result);
+    }
+    // If Microsoft extensions are disabled, this is just random garbage.
+    Kind = tok::unknown;
+    break;
+      
+  case '\n':
+  case '\r':
+    // If we are inside a preprocessor directive and we see the end of line,
+    // we know we are done with the directive, so return an EOD token.
+    if (ParsingPreprocessorDirective) {
+      // Done parsing the "line".
+      ParsingPreprocessorDirective = false;
+
+      // Restore comment saving mode, in case it was disabled for directive.
+      SetCommentRetentionState(PP->getCommentRetentionState());
+
+      // Since we consumed a newline, we are back at the start of a line.
+      IsAtStartOfLine = true;
+
+      Kind = tok::eod;
+      break;
+    }
+    // The returned token is at the start of the line.
+    Result.setFlag(Token::StartOfLine);
+    // No leading whitespace seen so far.
+    Result.clearFlag(Token::LeadingSpace);
+
+    if (SkipWhitespace(Result, CurPtr))
+      return; // KeepWhitespaceMode
+    goto LexNextToken;   // GCC isn't tail call eliminating.
+  case ' ':
+  case '\t':
+  case '\f':
+  case '\v':
+  SkipHorizontalWhitespace:
+    Result.setFlag(Token::LeadingSpace);
+    if (SkipWhitespace(Result, CurPtr))
+      return; // KeepWhitespaceMode
+
+  SkipIgnoredUnits:
+    CurPtr = BufferPtr;
+
+    // If the next token is obviously a // or /* */ comment, skip it efficiently
+    // too (without going through the big switch stmt).
+    if (CurPtr[0] == '/' && CurPtr[1] == '/' && !inKeepCommentMode() &&
+        LangOpts.BCPLComment && !LangOpts.TraditionalCPP) {
+      if (SkipBCPLComment(Result, CurPtr+2))
+        return; // There is a token to return.
+      goto SkipIgnoredUnits;
+    } else if (CurPtr[0] == '/' && CurPtr[1] == '*' && !inKeepCommentMode()) {
+      if (SkipBlockComment(Result, CurPtr+2))
+        return; // There is a token to return.
+      goto SkipIgnoredUnits;
+    } else if (isHorizontalWhitespace(*CurPtr)) {
+      goto SkipHorizontalWhitespace;
+    }
+    goto LexNextToken;   // GCC isn't tail call eliminating.
+      
+  // C99 6.4.4.1: Integer Constants.
+  // C99 6.4.4.2: Floating Constants.
+  case '0': case '1': case '2': case '3': case '4':
+  case '5': case '6': case '7': case '8': case '9':
+    // Notify MIOpt that we read a non-whitespace/non-comment token.
+    MIOpt.ReadToken();
+    return LexNumericConstant(Result, CurPtr);
+
+  case 'u':   // Identifier (uber) or C++0x UTF-8 or UTF-16 string literal
+    // Notify MIOpt that we read a non-whitespace/non-comment token.
+    MIOpt.ReadToken();
+
+    if (LangOpts.CPlusPlus0x) {
+      Char = getCharAndSize(CurPtr, SizeTmp);
+
+      // UTF-16 string literal
+      if (Char == '"')
+        return LexStringLiteral(Result, ConsumeChar(CurPtr, SizeTmp, Result),
+                                tok::utf16_string_literal);
+
+      // UTF-16 character constant
+      if (Char == '\'')
+        return LexCharConstant(Result, ConsumeChar(CurPtr, SizeTmp, Result),
+                               tok::utf16_char_constant);
+
+      // UTF-16 raw string literal
+      if (Char == 'R' && getCharAndSize(CurPtr + SizeTmp, SizeTmp2) == '"')
+        return LexRawStringLiteral(Result,
+                               ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                                           SizeTmp2, Result),
+                               tok::utf16_string_literal);
+
+      if (Char == '8') {
+        char Char2 = getCharAndSize(CurPtr + SizeTmp, SizeTmp2);
+
+        // UTF-8 string literal
+        if (Char2 == '"')
+          return LexStringLiteral(Result,
+                               ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                                           SizeTmp2, Result),
+                               tok::utf8_string_literal);
+
+        if (Char2 == 'R') {
+          unsigned SizeTmp3;
+          char Char3 = getCharAndSize(CurPtr + SizeTmp + SizeTmp2, SizeTmp3);
+          // UTF-8 raw string literal
+          if (Char3 == '"') {
+            return LexRawStringLiteral(Result,
+                   ConsumeChar(ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                                           SizeTmp2, Result),
+                               SizeTmp3, Result),
+                   tok::utf8_string_literal);
+          }
+        }
+      }
+    }
+
+    // treat u like the start of an identifier.
+    return LexIdentifier(Result, CurPtr);
+
+  case 'U':   // Identifier (Uber) or C++0x UTF-32 string literal
+    // Notify MIOpt that we read a non-whitespace/non-comment token.
+    MIOpt.ReadToken();
+
+    if (LangOpts.CPlusPlus0x) {
+      Char = getCharAndSize(CurPtr, SizeTmp);
+
+      // UTF-32 string literal
+      if (Char == '"')
+        return LexStringLiteral(Result, ConsumeChar(CurPtr, SizeTmp, Result),
+                                tok::utf32_string_literal);
+
+      // UTF-32 character constant
+      if (Char == '\'')
+        return LexCharConstant(Result, ConsumeChar(CurPtr, SizeTmp, Result),
+                               tok::utf32_char_constant);
+
+      // UTF-32 raw string literal
+      if (Char == 'R' && getCharAndSize(CurPtr + SizeTmp, SizeTmp2) == '"')
+        return LexRawStringLiteral(Result,
+                               ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                                           SizeTmp2, Result),
+                               tok::utf32_string_literal);
+    }
+
+    // treat U like the start of an identifier.
+    return LexIdentifier(Result, CurPtr);
+
+  case 'R': // Identifier or C++0x raw string literal
+    // Notify MIOpt that we read a non-whitespace/non-comment token.
+    MIOpt.ReadToken();
+
+    if (LangOpts.CPlusPlus0x) {
+      Char = getCharAndSize(CurPtr, SizeTmp);
+
+      if (Char == '"')
+        return LexRawStringLiteral(Result,
+                                   ConsumeChar(CurPtr, SizeTmp, Result),
+                                   tok::string_literal);
+    }
+
+    // treat R like the start of an identifier.
+    return LexIdentifier(Result, CurPtr);
+
+  case 'L':   // Identifier (Loony) or wide literal (L'x' or L"xyz").
+    // Notify MIOpt that we read a non-whitespace/non-comment token.
+    MIOpt.ReadToken();
+    Char = getCharAndSize(CurPtr, SizeTmp);
+
+    // Wide string literal.
+    if (Char == '"')
+      return LexStringLiteral(Result, ConsumeChar(CurPtr, SizeTmp, Result),
+                              tok::wide_string_literal);
+
+    // Wide raw string literal.
+    if (LangOpts.CPlusPlus0x && Char == 'R' &&
+        getCharAndSize(CurPtr + SizeTmp, SizeTmp2) == '"')
+      return LexRawStringLiteral(Result,
+                               ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                                           SizeTmp2, Result),
+                               tok::wide_string_literal);
+
+    // Wide character constant.
+    if (Char == '\'')
+      return LexCharConstant(Result, ConsumeChar(CurPtr, SizeTmp, Result),
+                             tok::wide_char_constant);
+    // FALL THROUGH, treating L like the start of an identifier.
+
+  // C99 6.4.2: Identifiers.
+  case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': case 'G':
+  case 'H': case 'I': case 'J': case 'K':    /*'L'*/case 'M': case 'N':
+  case 'O': case 'P': case 'Q':    /*'R'*/case 'S': case 'T':    /*'U'*/
+  case 'V': case 'W': case 'X': case 'Y': case 'Z':
+  case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': case 'g':
+  case 'h': case 'i': case 'j': case 'k': case 'l': case 'm': case 'n':
+  case 'o': case 'p': case 'q': case 'r': case 's': case 't':    /*'u'*/
+  case 'v': case 'w': case 'x': case 'y': case 'z':
+  case '_':
+    // Notify MIOpt that we read a non-whitespace/non-comment token.
+    MIOpt.ReadToken();
+    return LexIdentifier(Result, CurPtr);
+
+  case '$':   // $ in identifiers.
+    if (LangOpts.DollarIdents) {
+      if (!isLexingRawMode())
+        Diag(CurPtr-1, diag::ext_dollar_in_identifier);
+      // Notify MIOpt that we read a non-whitespace/non-comment token.
+      MIOpt.ReadToken();
+      return LexIdentifier(Result, CurPtr);
+    }
+
+    Kind = tok::unknown;
+    break;
+
+  // C99 6.4.4: Character Constants.
+  case '\'':
+    // Notify MIOpt that we read a non-whitespace/non-comment token.
+    MIOpt.ReadToken();
+    return LexCharConstant(Result, CurPtr, tok::char_constant);
+
+  // C99 6.4.5: String Literals.
+  case '"':
+    // Notify MIOpt that we read a non-whitespace/non-comment token.
+    MIOpt.ReadToken();
+    return LexStringLiteral(Result, CurPtr, tok::string_literal);
+
+  // C99 6.4.6: Punctuators.
+  case '?':
+    Kind = tok::question;
+    break;
+  case '[':
+    Kind = tok::l_square;
+    break;
+  case ']':
+    Kind = tok::r_square;
+    break;
+  case '(':
+    Kind = tok::l_paren;
+    break;
+  case ')':
+    Kind = tok::r_paren;
+    break;
+  case '{':
+    Kind = tok::l_brace;
+    break;
+  case '}':
+    Kind = tok::r_brace;
+    break;
+  case '.':
+    Char = getCharAndSize(CurPtr, SizeTmp);
+    if (Char >= '0' && Char <= '9') {
+      // Notify MIOpt that we read a non-whitespace/non-comment token.
+      MIOpt.ReadToken();
+
+      return LexNumericConstant(Result, ConsumeChar(CurPtr, SizeTmp, Result));
+    } else if (LangOpts.CPlusPlus && Char == '*') {
+      Kind = tok::periodstar;
+      CurPtr += SizeTmp;
+    } else if (Char == '.' &&
+               getCharAndSize(CurPtr+SizeTmp, SizeTmp2) == '.') {
+      Kind = tok::ellipsis;
+      CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                           SizeTmp2, Result);
+    } else {
+      Kind = tok::period;
+    }
+    break;
+  case '&':
+    Char = getCharAndSize(CurPtr, SizeTmp);
+    if (Char == '&') {
+      Kind = tok::ampamp;
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+    } else if (Char == '=') {
+      Kind = tok::ampequal;
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+    } else {
+      Kind = tok::amp;
+    }
+    break;
+  case '*':
+    if (getCharAndSize(CurPtr, SizeTmp) == '=') {
+      Kind = tok::starequal;
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+    } else {
+      Kind = tok::star;
+    }
+    break;
+  case '+':
+    Char = getCharAndSize(CurPtr, SizeTmp);
+    if (Char == '+') {
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+      Kind = tok::plusplus;
+    } else if (Char == '=') {
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+      Kind = tok::plusequal;
+    } else {
+      Kind = tok::plus;
+    }
+    break;
+  case '-':
+    Char = getCharAndSize(CurPtr, SizeTmp);
+    if (Char == '-') {      // --
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+      Kind = tok::minusminus;
+    } else if (Char == '>' && LangOpts.CPlusPlus &&
+               getCharAndSize(CurPtr+SizeTmp, SizeTmp2) == '*') {  // C++ ->*
+      CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                           SizeTmp2, Result);
+      Kind = tok::arrowstar;
+    } else if (Char == '>') {   // ->
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+      Kind = tok::arrow;
+    } else if (Char == '=') {   // -=
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+      Kind = tok::minusequal;
+    } else {
+      Kind = tok::minus;
+    }
+    break;
+  case '~':
+    Kind = tok::tilde;
+    break;
+  case '!':
+    if (getCharAndSize(CurPtr, SizeTmp) == '=') {
+      Kind = tok::exclaimequal;
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+    } else {
+      Kind = tok::exclaim;
+    }
+    break;
+  case '/':
+    // 6.4.9: Comments
+    Char = getCharAndSize(CurPtr, SizeTmp);
+    if (Char == '/') {         // BCPL comment.
+      // Even if BCPL comments are disabled (e.g. in C89 mode), we generally
+      // want to lex this as a comment.  There is one problem with this though,
+      // that in one particular corner case, this can change the behavior of the
+      // resultant program.  For example, In  "foo //**/ bar", C89 would lex
+      // this as "foo / bar" and langauges with BCPL comments would lex it as
+      // "foo".  Check to see if the character after the second slash is a '*'.
+      // If so, we will lex that as a "/" instead of the start of a comment.
+      // However, we never do this in -traditional-cpp mode.
+      if ((LangOpts.BCPLComment ||
+           getCharAndSize(CurPtr+SizeTmp, SizeTmp2) != '*') &&
+          !LangOpts.TraditionalCPP) {
+        if (SkipBCPLComment(Result, ConsumeChar(CurPtr, SizeTmp, Result)))
+          return; // There is a token to return.
+
+        // It is common for the tokens immediately after a // comment to be
+        // whitespace (indentation for the next line).  Instead of going through
+        // the big switch, handle it efficiently now.
+        goto SkipIgnoredUnits;
+      }
+    }
+
+    if (Char == '*') {  // /**/ comment.
+      if (SkipBlockComment(Result, ConsumeChar(CurPtr, SizeTmp, Result)))
+        return; // There is a token to return.
+      goto LexNextToken;   // GCC isn't tail call eliminating.
+    }
+
+    if (Char == '=') {
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+      Kind = tok::slashequal;
+    } else {
+      Kind = tok::slash;
+    }
+    break;
+  case '%':
+    Char = getCharAndSize(CurPtr, SizeTmp);
+    if (Char == '=') {
+      Kind = tok::percentequal;
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+    } else if (LangOpts.Digraphs && Char == '>') {
+      Kind = tok::r_brace;                             // '%>' -> '}'
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+    } else if (LangOpts.Digraphs && Char == ':') {
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+      Char = getCharAndSize(CurPtr, SizeTmp);
+      if (Char == '%' && getCharAndSize(CurPtr+SizeTmp, SizeTmp2) == ':') {
+        Kind = tok::hashhash;                          // '%:%:' -> '##'
+        CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                             SizeTmp2, Result);
+      } else if (Char == '@' && LangOpts.MicrosoftExt) {// %:@ -> #@ -> Charize
+        CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+        if (!isLexingRawMode())
+          Diag(BufferPtr, diag::ext_charize_microsoft);
+        Kind = tok::hashat;
+      } else {                                         // '%:' -> '#'
+        // We parsed a # character.  If this occurs at the start of the line,
+        // it's actually the start of a preprocessing directive.  Callback to
+        // the preprocessor to handle it.
+        // FIXME: -fpreprocessed mode??
+        if (Result.isAtStartOfLine() && !LexingRawMode && !Is_PragmaLexer) {
+          FormTokenWithChars(Result, CurPtr, tok::hash);
+          PP->HandleDirective(Result);
+
+          // As an optimization, if the preprocessor didn't switch lexers, tail
+          // recurse.
+          if (PP->isCurrentLexer(this)) {
+            // Start a new token. If this is a #include or something, the PP may
+            // want us starting at the beginning of the line again.  If so, set
+            // the StartOfLine flag and clear LeadingSpace.
+            if (IsAtStartOfLine) {
+              Result.setFlag(Token::StartOfLine);
+              Result.clearFlag(Token::LeadingSpace);
+              IsAtStartOfLine = false;
+            }
+            goto LexNextToken;   // GCC isn't tail call eliminating.
+          }
+
+          return PP->Lex(Result);
+        }
+
+        Kind = tok::hash;
+      }
+    } else {
+      Kind = tok::percent;
+    }
+    break;
+  case '<':
+    Char = getCharAndSize(CurPtr, SizeTmp);
+    if (ParsingFilename) {
+      return LexAngledStringLiteral(Result, CurPtr);
+    } else if (Char == '<') {
+      char After = getCharAndSize(CurPtr+SizeTmp, SizeTmp2);
+      if (After == '=') {
+        Kind = tok::lesslessequal;
+        CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                             SizeTmp2, Result);
+      } else if (After == '<' && IsStartOfConflictMarker(CurPtr-1)) {
+        // If this is actually a '<<<<<<<' version control conflict marker,
+        // recognize it as such and recover nicely.
+        goto LexNextToken;
+      } else if (After == '<' && HandleEndOfConflictMarker(CurPtr-1)) {
+        // If this is '<<<<' and we're in a Perforce-style conflict marker,
+        // ignore it.
+        goto LexNextToken;
+      } else if (LangOpts.CUDA && After == '<') {
+        Kind = tok::lesslessless;
+        CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                             SizeTmp2, Result);
+      } else {
+        CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+        Kind = tok::lessless;
+      }
+    } else if (Char == '=') {
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+      Kind = tok::lessequal;
+    } else if (LangOpts.Digraphs && Char == ':') {     // '<:' -> '['
+      if (LangOpts.CPlusPlus0x &&
+          getCharAndSize(CurPtr + SizeTmp, SizeTmp2) == ':') {
+        // C++0x [lex.pptoken]p3:
+        //  Otherwise, if the next three characters are <:: and the subsequent
+        //  character is neither : nor >, the < is treated as a preprocessor
+        //  token by itself and not as the first character of the alternative
+        //  token <:.
+        unsigned SizeTmp3;
+        char After = getCharAndSize(CurPtr + SizeTmp + SizeTmp2, SizeTmp3);
+        if (After != ':' && After != '>') {
+          Kind = tok::less;
+          if (!isLexingRawMode())
+            Diag(BufferPtr, diag::warn_cxx98_compat_less_colon_colon);
+          break;
+        }
+      }
+
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+      Kind = tok::l_square;
+    } else if (LangOpts.Digraphs && Char == '%') {     // '<%' -> '{'
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+      Kind = tok::l_brace;
+    } else {
+      Kind = tok::less;
+    }
+    break;
+  case '>':
+    Char = getCharAndSize(CurPtr, SizeTmp);
+    if (Char == '=') {
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+      Kind = tok::greaterequal;
+    } else if (Char == '>') {
+      char After = getCharAndSize(CurPtr+SizeTmp, SizeTmp2);
+      if (After == '=') {
+        CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                             SizeTmp2, Result);
+        Kind = tok::greatergreaterequal;
+      } else if (After == '>' && IsStartOfConflictMarker(CurPtr-1)) {
+        // If this is actually a '>>>>' conflict marker, recognize it as such
+        // and recover nicely.
+        goto LexNextToken;
+      } else if (After == '>' && HandleEndOfConflictMarker(CurPtr-1)) {
+        // If this is '>>>>>>>' and we're in a conflict marker, ignore it.
+        goto LexNextToken;
+      } else if (LangOpts.CUDA && After == '>') {
+        Kind = tok::greatergreatergreater;
+        CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result),
+                             SizeTmp2, Result);
+      } else {
+        CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+        Kind = tok::greatergreater;
+      }
+      
+    } else {
+      Kind = tok::greater;
+    }
+    break;
+  case '^':
+    Char = getCharAndSize(CurPtr, SizeTmp);
+    if (Char == '=') {
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+      Kind = tok::caretequal;
+    } else {
+      Kind = tok::caret;
+    }
+    break;
+  case '|':
+    Char = getCharAndSize(CurPtr, SizeTmp);
+    if (Char == '=') {
+      Kind = tok::pipeequal;
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+    } else if (Char == '|') {
+      // If this is '|||||||' and we're in a conflict marker, ignore it.
+      if (CurPtr[1] == '|' && HandleEndOfConflictMarker(CurPtr-1))
+        goto LexNextToken;
+      Kind = tok::pipepipe;
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+    } else {
+      Kind = tok::pipe;
+    }
+    break;
+  case ':':
+    Char = getCharAndSize(CurPtr, SizeTmp);
+    if (LangOpts.Digraphs && Char == '>') {
+      Kind = tok::r_square; // ':>' -> ']'
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+    } else if (LangOpts.CPlusPlus && Char == ':') {
+      Kind = tok::coloncolon;
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+    } else {
+      Kind = tok::colon;
+    }
+    break;
+  case ';':
+    Kind = tok::semi;
+    break;
+  case '=':
+    Char = getCharAndSize(CurPtr, SizeTmp);
+    if (Char == '=') {
+      // If this is '====' and we're in a conflict marker, ignore it.
+      if (CurPtr[1] == '=' && HandleEndOfConflictMarker(CurPtr-1))
+        goto LexNextToken;
+      
+      Kind = tok::equalequal;
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+    } else {
+      Kind = tok::equal;
+    }
+    break;
+  case ',':
+    Kind = tok::comma;
+    break;
+  case '#':
+    Char = getCharAndSize(CurPtr, SizeTmp);
+    if (Char == '#') {
+      Kind = tok::hashhash;
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+    } else if (Char == '@' && LangOpts.MicrosoftExt) {  // #@ -> Charize
+      Kind = tok::hashat;
+      if (!isLexingRawMode())
+        Diag(BufferPtr, diag::ext_charize_microsoft);
+      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result);
+    } else {
+      // We parsed a # character.  If this occurs at the start of the line,
+      // it's actually the start of a preprocessing directive.  Callback to
+      // the preprocessor to handle it.
+      // FIXME: -fpreprocessed mode??
+      if (Result.isAtStartOfLine() && !LexingRawMode && !Is_PragmaLexer) {
+        FormTokenWithChars(Result, CurPtr, tok::hash);
+        PP->HandleDirective(Result);
+
+        // As an optimization, if the preprocessor didn't switch lexers, tail
+        // recurse.
+        if (PP->isCurrentLexer(this)) {
+          // Start a new token.  If this is a #include or something, the PP may
+          // want us starting at the beginning of the line again.  If so, set
+          // the StartOfLine flag and clear LeadingSpace.
+          if (IsAtStartOfLine) {
+            Result.setFlag(Token::StartOfLine);
+            Result.clearFlag(Token::LeadingSpace);
+            IsAtStartOfLine = false;
+          }
+          goto LexNextToken;   // GCC isn't tail call eliminating.
+        }
+        return PP->Lex(Result);
+      }
+
+      Kind = tok::hash;
+    }
+    break;
+
+  case '@':
+    // Objective C support.
+    if (CurPtr[-1] == '@' && LangOpts.ObjC1)
+      Kind = tok::at;
+    else
+      Kind = tok::unknown;
+    break;
+
+  case '\\':
+    // FIXME: UCN's.
+    // FALL THROUGH.
+  default:
+    Kind = tok::unknown;
+    break;
+  }
+
+  // Notify MIOpt that we read a non-whitespace/non-comment token.
+  MIOpt.ReadToken();
+
+  // Update the location of token as well as BufferPtr.
+  FormTokenWithChars(Result, CurPtr, Kind);
+}