Merge branch 'master' of ssh://bitbucket.org/czan/honours

1 files changed, 1400 insertions, 0 deletions

diff --git a/clang/lib/Lex/LiteralSupport.cpp b/clang/lib/Lex/LiteralSupport.cpp
new file mode 100644
index 0000000..c1d228b
--- /dev/null
+++ b/clang/lib/Lex/LiteralSupport.cpp
@@ -0,0 +1,1400 @@
+//===--- LiteralSupport.cpp - Code to parse and process literals ----------===//
+//
+//                     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 NumericLiteralParser, CharLiteralParser, and
+// StringLiteralParser interfaces.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Lex/LiteralSupport.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/Lex/LexDiagnostic.h"
+#include "clang/Basic/TargetInfo.h"
+#include "clang/Basic/ConvertUTF.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/ErrorHandling.h"
+using namespace clang;
+
+/// HexDigitValue - Return the value of the specified hex digit, or -1 if it's
+/// not valid.
+static int HexDigitValue(char C) {
+  if (C >= '0' && C <= '9') return C-'0';
+  if (C >= 'a' && C <= 'f') return C-'a'+10;
+  if (C >= 'A' && C <= 'F') return C-'A'+10;
+  return -1;
+}
+
+static unsigned getCharWidth(tok::TokenKind kind, const TargetInfo &Target) {
+  switch (kind) {
+  default: llvm_unreachable("Unknown token type!");
+  case tok::char_constant:
+  case tok::string_literal:
+  case tok::utf8_string_literal:
+    return Target.getCharWidth();
+  case tok::wide_char_constant:
+  case tok::wide_string_literal:
+    return Target.getWCharWidth();
+  case tok::utf16_char_constant:
+  case tok::utf16_string_literal:
+    return Target.getChar16Width();
+  case tok::utf32_char_constant:
+  case tok::utf32_string_literal:
+    return Target.getChar32Width();
+  }
+}
+
+/// ProcessCharEscape - Parse a standard C escape sequence, which can occur in
+/// either a character or a string literal.
+static unsigned ProcessCharEscape(const char *&ThisTokBuf,
+                                  const char *ThisTokEnd, bool &HadError,
+                                  FullSourceLoc Loc, unsigned CharWidth,
+                                  DiagnosticsEngine *Diags) {
+  // Skip the '\' char.
+  ++ThisTokBuf;
+
+  // We know that this character can't be off the end of the buffer, because
+  // that would have been \", which would not have been the end of string.
+  unsigned ResultChar = *ThisTokBuf++;
+  switch (ResultChar) {
+  // These map to themselves.
+  case '\\': case '\'': case '"': case '?': break;
+
+    // These have fixed mappings.
+  case 'a':
+    // TODO: K&R: the meaning of '\\a' is different in traditional C
+    ResultChar = 7;
+    break;
+  case 'b':
+    ResultChar = 8;
+    break;
+  case 'e':
+    if (Diags)
+      Diags->Report(Loc, diag::ext_nonstandard_escape) << "e";
+    ResultChar = 27;
+    break;
+  case 'E':
+    if (Diags)
+      Diags->Report(Loc, diag::ext_nonstandard_escape) << "E";
+    ResultChar = 27;
+    break;
+  case 'f':
+    ResultChar = 12;
+    break;
+  case 'n':
+    ResultChar = 10;
+    break;
+  case 'r':
+    ResultChar = 13;
+    break;
+  case 't':
+    ResultChar = 9;
+    break;
+  case 'v':
+    ResultChar = 11;
+    break;
+  case 'x': { // Hex escape.
+    ResultChar = 0;
+    if (ThisTokBuf == ThisTokEnd || !isxdigit(*ThisTokBuf)) {
+      if (Diags)
+        Diags->Report(Loc, diag::err_hex_escape_no_digits);
+      HadError = 1;
+      break;
+    }
+
+    // Hex escapes are a maximal series of hex digits.
+    bool Overflow = false;
+    for (; ThisTokBuf != ThisTokEnd; ++ThisTokBuf) {
+      int CharVal = HexDigitValue(ThisTokBuf[0]);
+      if (CharVal == -1) break;
+      // About to shift out a digit?
+      Overflow |= (ResultChar & 0xF0000000) ? true : false;
+      ResultChar <<= 4;
+      ResultChar |= CharVal;
+    }
+
+    // See if any bits will be truncated when evaluated as a character.
+    if (CharWidth != 32 && (ResultChar >> CharWidth) != 0) {
+      Overflow = true;
+      ResultChar &= ~0U >> (32-CharWidth);
+    }
+
+    // Check for overflow.
+    if (Overflow && Diags)   // Too many digits to fit in
+      Diags->Report(Loc, diag::warn_hex_escape_too_large);
+    break;
+  }
+  case '0': case '1': case '2': case '3':
+  case '4': case '5': case '6': case '7': {
+    // Octal escapes.
+    --ThisTokBuf;
+    ResultChar = 0;
+
+    // Octal escapes are a series of octal digits with maximum length 3.
+    // "\0123" is a two digit sequence equal to "\012" "3".
+    unsigned NumDigits = 0;
+    do {
+      ResultChar <<= 3;
+      ResultChar |= *ThisTokBuf++ - '0';
+      ++NumDigits;
+    } while (ThisTokBuf != ThisTokEnd && NumDigits < 3 &&
+             ThisTokBuf[0] >= '0' && ThisTokBuf[0] <= '7');
+
+    // Check for overflow.  Reject '\777', but not L'\777'.
+    if (CharWidth != 32 && (ResultChar >> CharWidth) != 0) {
+      if (Diags)
+        Diags->Report(Loc, diag::warn_octal_escape_too_large);
+      ResultChar &= ~0U >> (32-CharWidth);
+    }
+    break;
+  }
+
+    // Otherwise, these are not valid escapes.
+  case '(': case '{': case '[': case '%':
+    // GCC accepts these as extensions.  We warn about them as such though.
+    if (Diags)
+      Diags->Report(Loc, diag::ext_nonstandard_escape)
+        << std::string()+(char)ResultChar;
+    break;
+  default:
+    if (Diags == 0)
+      break;
+      
+    if (isgraph(ResultChar))
+      Diags->Report(Loc, diag::ext_unknown_escape)
+        << std::string()+(char)ResultChar;
+    else
+      Diags->Report(Loc, diag::ext_unknown_escape)
+        << "x"+llvm::utohexstr(ResultChar);
+    break;
+  }
+
+  return ResultChar;
+}
+
+/// ProcessUCNEscape - Read the Universal Character Name, check constraints and
+/// return the UTF32.
+static bool ProcessUCNEscape(const char *ThisTokBegin, const char *&ThisTokBuf,
+                             const char *ThisTokEnd,
+                             uint32_t &UcnVal, unsigned short &UcnLen,
+                             FullSourceLoc Loc, DiagnosticsEngine *Diags, 
+                             const LangOptions &Features,
+                             bool in_char_string_literal = false) {
+  if (!Features.CPlusPlus && !Features.C99 && Diags)
+    Diags->Report(Loc, diag::warn_ucn_not_valid_in_c89);
+
+  const char *UcnBegin = ThisTokBuf;
+
+  // Skip the '\u' char's.
+  ThisTokBuf += 2;
+
+  if (ThisTokBuf == ThisTokEnd || !isxdigit(*ThisTokBuf)) {
+    if (Diags)
+      Diags->Report(Loc, diag::err_ucn_escape_no_digits);
+    return false;
+  }
+  UcnLen = (ThisTokBuf[-1] == 'u' ? 4 : 8);
+  unsigned short UcnLenSave = UcnLen;
+  for (; ThisTokBuf != ThisTokEnd && UcnLenSave; ++ThisTokBuf, UcnLenSave--) {
+    int CharVal = HexDigitValue(ThisTokBuf[0]);
+    if (CharVal == -1) break;
+    UcnVal <<= 4;
+    UcnVal |= CharVal;
+  }
+  // If we didn't consume the proper number of digits, there is a problem.
+  if (UcnLenSave) {
+    if (Diags) {
+      SourceLocation L =
+        Lexer::AdvanceToTokenCharacter(Loc, UcnBegin - ThisTokBegin,
+                                       Loc.getManager(), Features);
+      Diags->Report(L, diag::err_ucn_escape_incomplete);
+    }
+    return false;
+  }
+
+  // Check UCN constraints (C99 6.4.3p2) [C++11 lex.charset p2]
+  if ((0xD800 <= UcnVal && UcnVal <= 0xDFFF) || // surrogate codepoints
+      UcnVal > 0x10FFFF) {                      // maximum legal UTF32 value
+    if (Diags)
+      Diags->Report(Loc, diag::err_ucn_escape_invalid);
+    return false;
+  }
+
+  // C++11 allows UCNs that refer to control characters and basic source
+  // characters inside character and string literals
+  if (UcnVal < 0xa0 &&
+      (UcnVal != 0x24 && UcnVal != 0x40 && UcnVal != 0x60)) {  // $, @, `
+    bool IsError = (!Features.CPlusPlus0x || !in_char_string_literal);
+    if (Diags) {
+      SourceLocation UcnBeginLoc =
+        Lexer::AdvanceToTokenCharacter(Loc, UcnBegin - ThisTokBegin,
+                                       Loc.getManager(), Features);
+      char BasicSCSChar = UcnVal;
+      if (UcnVal >= 0x20 && UcnVal < 0x7f)
+        Diags->Report(UcnBeginLoc, IsError ? diag::err_ucn_escape_basic_scs :
+                      diag::warn_cxx98_compat_literal_ucn_escape_basic_scs)
+          << StringRef(&BasicSCSChar, 1);
+      else
+        Diags->Report(UcnBeginLoc, IsError ? diag::err_ucn_control_character :
+                      diag::warn_cxx98_compat_literal_ucn_control_character);
+    }
+    if (IsError)
+      return false;
+  }
+
+  return true;
+}
+
+/// EncodeUCNEscape - Read the Universal Character Name, check constraints and
+/// convert the UTF32 to UTF8 or UTF16. This is a subroutine of
+/// StringLiteralParser. When we decide to implement UCN's for identifiers,
+/// we will likely rework our support for UCN's.
+static void EncodeUCNEscape(const char *ThisTokBegin, const char *&ThisTokBuf,
+                            const char *ThisTokEnd,
+                            char *&ResultBuf, bool &HadError,
+                            FullSourceLoc Loc, unsigned CharByteWidth,
+                            DiagnosticsEngine *Diags,
+                            const LangOptions &Features) {
+  typedef uint32_t UTF32;
+  UTF32 UcnVal = 0;
+  unsigned short UcnLen = 0;
+  if (!ProcessUCNEscape(ThisTokBegin, ThisTokBuf, ThisTokEnd, UcnVal, UcnLen,
+                        Loc, Diags, Features, true)) {
+    HadError = 1;
+    return;
+  }
+
+  assert((CharByteWidth == 1 || CharByteWidth == 2 || CharByteWidth) &&
+         "only character widths of 1, 2, or 4 bytes supported");
+
+  (void)UcnLen;
+  assert((UcnLen== 4 || UcnLen== 8) && "only ucn length of 4 or 8 supported");
+
+  if (CharByteWidth == 4) {
+    // FIXME: Make the type of the result buffer correct instead of
+    // using reinterpret_cast.
+    UTF32 *ResultPtr = reinterpret_cast<UTF32*>(ResultBuf);
+    *ResultPtr = UcnVal;
+    ResultBuf += 4;
+    return;
+  }
+
+  if (CharByteWidth == 2) {
+    // FIXME: Make the type of the result buffer correct instead of
+    // using reinterpret_cast.
+    UTF16 *ResultPtr = reinterpret_cast<UTF16*>(ResultBuf);
+
+    if (UcnVal < (UTF32)0xFFFF) {
+      *ResultPtr = UcnVal;
+      ResultBuf += 2;
+      return;
+    }
+
+    // Convert to UTF16.
+    UcnVal -= 0x10000;
+    *ResultPtr     = 0xD800 + (UcnVal >> 10);
+    *(ResultPtr+1) = 0xDC00 + (UcnVal & 0x3FF);
+    ResultBuf += 4;
+    return;
+  }
+
+  assert(CharByteWidth == 1 && "UTF-8 encoding is only for 1 byte characters");
+
+  // Now that we've parsed/checked the UCN, we convert from UTF32->UTF8.
+  // The conversion below was inspired by:
+  //   http://www.unicode.org/Public/PROGRAMS/CVTUTF/ConvertUTF.c
+  // First, we determine how many bytes the result will require.
+  typedef uint8_t UTF8;
+
+  unsigned short bytesToWrite = 0;
+  if (UcnVal < (UTF32)0x80)
+    bytesToWrite = 1;
+  else if (UcnVal < (UTF32)0x800)
+    bytesToWrite = 2;
+  else if (UcnVal < (UTF32)0x10000)
+    bytesToWrite = 3;
+  else
+    bytesToWrite = 4;
+
+  const unsigned byteMask = 0xBF;
+  const unsigned byteMark = 0x80;
+
+  // Once the bits are split out into bytes of UTF8, this is a mask OR-ed
+  // into the first byte, depending on how many bytes follow.
+  static const UTF8 firstByteMark[5] = {
+    0x00, 0x00, 0xC0, 0xE0, 0xF0
+  };
+  // Finally, we write the bytes into ResultBuf.
+  ResultBuf += bytesToWrite;
+  switch (bytesToWrite) { // note: everything falls through.
+    case 4: *--ResultBuf = (UTF8)((UcnVal | byteMark) & byteMask); UcnVal >>= 6;
+    case 3: *--ResultBuf = (UTF8)((UcnVal | byteMark) & byteMask); UcnVal >>= 6;
+    case 2: *--ResultBuf = (UTF8)((UcnVal | byteMark) & byteMask); UcnVal >>= 6;
+    case 1: *--ResultBuf = (UTF8) (UcnVal | firstByteMark[bytesToWrite]);
+  }
+  // Update the buffer.
+  ResultBuf += bytesToWrite;
+}
+
+
+///       integer-constant: [C99 6.4.4.1]
+///         decimal-constant integer-suffix
+///         octal-constant integer-suffix
+///         hexadecimal-constant integer-suffix
+///       user-defined-integer-literal: [C++11 lex.ext]
+///         decimal-literal ud-suffix
+///         octal-literal ud-suffix
+///         hexadecimal-literal ud-suffix
+///       decimal-constant:
+///         nonzero-digit
+///         decimal-constant digit
+///       octal-constant:
+///         0
+///         octal-constant octal-digit
+///       hexadecimal-constant:
+///         hexadecimal-prefix hexadecimal-digit
+///         hexadecimal-constant hexadecimal-digit
+///       hexadecimal-prefix: one of
+///         0x 0X
+///       integer-suffix:
+///         unsigned-suffix [long-suffix]
+///         unsigned-suffix [long-long-suffix]
+///         long-suffix [unsigned-suffix]
+///         long-long-suffix [unsigned-sufix]
+///       nonzero-digit:
+///         1 2 3 4 5 6 7 8 9
+///       octal-digit:
+///         0 1 2 3 4 5 6 7
+///       hexadecimal-digit:
+///         0 1 2 3 4 5 6 7 8 9
+///         a b c d e f
+///         A B C D E F
+///       unsigned-suffix: one of
+///         u U
+///       long-suffix: one of
+///         l L
+///       long-long-suffix: one of
+///         ll LL
+///
+///       floating-constant: [C99 6.4.4.2]
+///         TODO: add rules...
+///
+NumericLiteralParser::
+NumericLiteralParser(const char *begin, const char *end,
+                     SourceLocation TokLoc, Preprocessor &pp)
+  : PP(pp), ThisTokBegin(begin), ThisTokEnd(end) {
+
+  // This routine assumes that the range begin/end matches the regex for integer
+  // and FP constants (specifically, the 'pp-number' regex), and assumes that
+  // the byte at "*end" is both valid and not part of the regex.  Because of
+  // this, it doesn't have to check for 'overscan' in various places.
+  assert(!isalnum(*end) && *end != '.' && *end != '_' &&
+         "Lexer didn't maximally munch?");
+
+  s = DigitsBegin = begin;
+  saw_exponent = false;
+  saw_period = false;
+  saw_ud_suffix = false;
+  isLong = false;
+  isUnsigned = false;
+  isLongLong = false;
+  isFloat = false;
+  isImaginary = false;
+  isMicrosoftInteger = false;
+  hadError = false;
+
+  if (*s == '0') { // parse radix
+    ParseNumberStartingWithZero(TokLoc);
+    if (hadError)
+      return;
+  } else { // the first digit is non-zero
+    radix = 10;
+    s = SkipDigits(s);
+    if (s == ThisTokEnd) {
+      // Done.
+    } else if (isxdigit(*s) && !(*s == 'e' || *s == 'E')) {
+      PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s-begin),
+              diag::err_invalid_decimal_digit) << StringRef(s, 1);
+      hadError = true;
+      return;
+    } else if (*s == '.') {
+      s++;
+      saw_period = true;
+      s = SkipDigits(s);
+    }
+    if ((*s == 'e' || *s == 'E')) { // exponent
+      const char *Exponent = s;
+      s++;
+      saw_exponent = true;
+      if (*s == '+' || *s == '-')  s++; // sign
+      const char *first_non_digit = SkipDigits(s);
+      if (first_non_digit != s) {
+        s = first_non_digit;
+      } else {
+        PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, Exponent-begin),
+                diag::err_exponent_has_no_digits);
+        hadError = true;
+        return;
+      }
+    }
+  }
+
+  SuffixBegin = s;
+
+  // Parse the suffix.  At this point we can classify whether we have an FP or
+  // integer constant.
+  bool isFPConstant = isFloatingLiteral();
+
+  // Loop over all of the characters of the suffix.  If we see something bad,
+  // we break out of the loop.
+  for (; s != ThisTokEnd; ++s) {
+    switch (*s) {
+    case 'f':      // FP Suffix for "float"
+    case 'F':
+      if (!isFPConstant) break;  // Error for integer constant.
+      if (isFloat || isLong) break; // FF, LF invalid.
+      isFloat = true;
+      continue;  // Success.
+    case 'u':
+    case 'U':
+      if (isFPConstant) break;  // Error for floating constant.
+      if (isUnsigned) break;    // Cannot be repeated.
+      isUnsigned = true;
+      continue;  // Success.
+    case 'l':
+    case 'L':
+      if (isLong || isLongLong) break;  // Cannot be repeated.
+      if (isFloat) break;               // LF invalid.
+
+      // Check for long long.  The L's need to be adjacent and the same case.
+      if (s+1 != ThisTokEnd && s[1] == s[0]) {
+        if (isFPConstant) break;        // long long invalid for floats.
+        isLongLong = true;
+        ++s;  // Eat both of them.
+      } else {
+        isLong = true;
+      }
+      continue;  // Success.
+    case 'i':
+    case 'I':
+      if (PP.getLangOpts().MicrosoftExt) {
+        if (isFPConstant || isLong || isLongLong) break;
+
+        // Allow i8, i16, i32, i64, and i128.
+        if (s + 1 != ThisTokEnd) {
+          switch (s[1]) {
+            case '8':
+              s += 2; // i8 suffix
+              isMicrosoftInteger = true;
+              break;
+            case '1':
+              if (s + 2 == ThisTokEnd) break;
+              if (s[2] == '6') {
+                s += 3; // i16 suffix
+                isMicrosoftInteger = true;
+              }
+              else if (s[2] == '2') {
+                if (s + 3 == ThisTokEnd) break;
+                if (s[3] == '8') {
+                  s += 4; // i128 suffix
+                  isMicrosoftInteger = true;
+                }
+              }
+              break;
+            case '3':
+              if (s + 2 == ThisTokEnd) break;
+              if (s[2] == '2') {
+                s += 3; // i32 suffix
+                isLong = true;
+                isMicrosoftInteger = true;
+              }
+              break;
+            case '6':
+              if (s + 2 == ThisTokEnd) break;
+              if (s[2] == '4') {
+                s += 3; // i64 suffix
+                isLongLong = true;
+                isMicrosoftInteger = true;
+              }
+              break;
+            default:
+              break;
+          }
+          break;
+        }
+      }
+      // fall through.
+    case 'j':
+    case 'J':
+      if (isImaginary) break;   // Cannot be repeated.
+      PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s-begin),
+              diag::ext_imaginary_constant);
+      isImaginary = true;
+      continue;  // Success.
+    }
+    // If we reached here, there was an error or a ud-suffix.
+    break;
+  }
+
+  if (s != ThisTokEnd) {
+    if (PP.getLangOpts().CPlusPlus0x && s == SuffixBegin && *s == '_') {
+      // We have a ud-suffix! By C++11 [lex.ext]p10, ud-suffixes not starting
+      // with an '_' are ill-formed.
+      saw_ud_suffix = true;
+      return;
+    }
+
+    // Report an error if there are any.
+    PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, SuffixBegin-begin),
+            isFPConstant ? diag::err_invalid_suffix_float_constant :
+                           diag::err_invalid_suffix_integer_constant)
+      << StringRef(SuffixBegin, ThisTokEnd-SuffixBegin);
+    hadError = true;
+    return;
+  }
+}
+
+/// ParseNumberStartingWithZero - This method is called when the first character
+/// of the number is found to be a zero.  This means it is either an octal
+/// number (like '04') or a hex number ('0x123a') a binary number ('0b1010') or
+/// a floating point number (01239.123e4).  Eat the prefix, determining the
+/// radix etc.
+void NumericLiteralParser::ParseNumberStartingWithZero(SourceLocation TokLoc) {
+  assert(s[0] == '0' && "Invalid method call");
+  s++;
+
+  // Handle a hex number like 0x1234.
+  if ((*s == 'x' || *s == 'X') && (isxdigit(s[1]) || s[1] == '.')) {
+    s++;
+    radix = 16;
+    DigitsBegin = s;
+    s = SkipHexDigits(s);
+    bool noSignificand = (s == DigitsBegin);
+    if (s == ThisTokEnd) {
+      // Done.
+    } else if (*s == '.') {
+      s++;
+      saw_period = true;
+      const char *floatDigitsBegin = s;
+      s = SkipHexDigits(s);
+      noSignificand &= (floatDigitsBegin == s);
+    }
+
+    if (noSignificand) {
+      PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s-ThisTokBegin), \
+        diag::err_hexconstant_requires_digits);
+      hadError = true;
+      return;
+    }
+
+    // A binary exponent can appear with or with a '.'. If dotted, the
+    // binary exponent is required.
+    if (*s == 'p' || *s == 'P') {
+      const char *Exponent = s;
+      s++;
+      saw_exponent = true;
+      if (*s == '+' || *s == '-')  s++; // sign
+      const char *first_non_digit = SkipDigits(s);
+      if (first_non_digit == s) {
+        PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, Exponent-ThisTokBegin),
+                diag::err_exponent_has_no_digits);
+        hadError = true;
+        return;
+      }
+      s = first_non_digit;
+
+      if (!PP.getLangOpts().HexFloats)
+        PP.Diag(TokLoc, diag::ext_hexconstant_invalid);
+    } else if (saw_period) {
+      PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s-ThisTokBegin),
+              diag::err_hexconstant_requires_exponent);
+      hadError = true;
+    }
+    return;
+  }
+
+  // Handle simple binary numbers 0b01010
+  if (*s == 'b' || *s == 'B') {
+    // 0b101010 is a GCC extension.
+    PP.Diag(TokLoc, diag::ext_binary_literal);
+    ++s;
+    radix = 2;
+    DigitsBegin = s;
+    s = SkipBinaryDigits(s);
+    if (s == ThisTokEnd) {
+      // Done.
+    } else if (isxdigit(*s)) {
+      PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s-ThisTokBegin),
+              diag::err_invalid_binary_digit) << StringRef(s, 1);
+      hadError = true;
+    }
+    // Other suffixes will be diagnosed by the caller.
+    return;
+  }
+
+  // For now, the radix is set to 8. If we discover that we have a
+  // floating point constant, the radix will change to 10. Octal floating
+  // point constants are not permitted (only decimal and hexadecimal).
+  radix = 8;
+  DigitsBegin = s;
+  s = SkipOctalDigits(s);
+  if (s == ThisTokEnd)
+    return; // Done, simple octal number like 01234
+
+  // If we have some other non-octal digit that *is* a decimal digit, see if
+  // this is part of a floating point number like 094.123 or 09e1.
+  if (isdigit(*s)) {
+    const char *EndDecimal = SkipDigits(s);
+    if (EndDecimal[0] == '.' || EndDecimal[0] == 'e' || EndDecimal[0] == 'E') {
+      s = EndDecimal;
+      radix = 10;
+    }
+  }
+
+  // If we have a hex digit other than 'e' (which denotes a FP exponent) then
+  // the code is using an incorrect base.
+  if (isxdigit(*s) && *s != 'e' && *s != 'E') {
+    PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, s-ThisTokBegin),
+            diag::err_invalid_octal_digit) << StringRef(s, 1);
+    hadError = true;
+    return;
+  }
+
+  if (*s == '.') {
+    s++;
+    radix = 10;
+    saw_period = true;
+    s = SkipDigits(s); // Skip suffix.
+  }
+  if (*s == 'e' || *s == 'E') { // exponent
+    const char *Exponent = s;
+    s++;
+    radix = 10;
+    saw_exponent = true;
+    if (*s == '+' || *s == '-')  s++; // sign
+    const char *first_non_digit = SkipDigits(s);
+    if (first_non_digit != s) {
+      s = first_non_digit;
+    } else {
+      PP.Diag(PP.AdvanceToTokenCharacter(TokLoc, Exponent-ThisTokBegin),
+              diag::err_exponent_has_no_digits);
+      hadError = true;
+      return;
+    }
+  }
+}
+
+
+/// GetIntegerValue - Convert this numeric literal value to an APInt that
+/// matches Val's input width.  If there is an overflow, set Val to the low bits
+/// of the result and return true.  Otherwise, return false.
+bool NumericLiteralParser::GetIntegerValue(llvm::APInt &Val) {
+  // Fast path: Compute a conservative bound on the maximum number of
+  // bits per digit in this radix. If we can't possibly overflow a
+  // uint64 based on that bound then do the simple conversion to
+  // integer. This avoids the expensive overflow checking below, and
+  // handles the common cases that matter (small decimal integers and
+  // hex/octal values which don't overflow).
+  unsigned MaxBitsPerDigit = 1;
+  while ((1U << MaxBitsPerDigit) < radix)
+    MaxBitsPerDigit += 1;
+  if ((SuffixBegin - DigitsBegin) * MaxBitsPerDigit <= 64) {
+    uint64_t N = 0;
+    for (s = DigitsBegin; s != SuffixBegin; ++s)
+      N = N*radix + HexDigitValue(*s);
+
+    // This will truncate the value to Val's input width. Simply check
+    // for overflow by comparing.
+    Val = N;
+    return Val.getZExtValue() != N;
+  }
+
+  Val = 0;
+  s = DigitsBegin;
+
+  llvm::APInt RadixVal(Val.getBitWidth(), radix);
+  llvm::APInt CharVal(Val.getBitWidth(), 0);
+  llvm::APInt OldVal = Val;
+
+  bool OverflowOccurred = false;
+  while (s < SuffixBegin) {
+    unsigned C = HexDigitValue(*s++);
+
+    // If this letter is out of bound for this radix, reject it.
+    assert(C < radix && "NumericLiteralParser ctor should have rejected this");
+
+    CharVal = C;
+
+    // Add the digit to the value in the appropriate radix.  If adding in digits
+    // made the value smaller, then this overflowed.
+    OldVal = Val;
+
+    // Multiply by radix, did overflow occur on the multiply?
+    Val *= RadixVal;
+    OverflowOccurred |= Val.udiv(RadixVal) != OldVal;
+
+    // Add value, did overflow occur on the value?
+    //   (a + b) ult b  <=> overflow
+    Val += CharVal;
+    OverflowOccurred |= Val.ult(CharVal);
+  }
+  return OverflowOccurred;
+}
+
+llvm::APFloat::opStatus
+NumericLiteralParser::GetFloatValue(llvm::APFloat &Result) {
+  using llvm::APFloat;
+
+  unsigned n = std::min(SuffixBegin - ThisTokBegin, ThisTokEnd - ThisTokBegin);
+  return Result.convertFromString(StringRef(ThisTokBegin, n),
+                                  APFloat::rmNearestTiesToEven);
+}
+
+
+///       user-defined-character-literal: [C++11 lex.ext]
+///         character-literal ud-suffix
+///       ud-suffix:
+///         identifier
+///       character-literal: [C++11 lex.ccon]
+///         ' c-char-sequence '
+///         u' c-char-sequence '
+///         U' c-char-sequence '
+///         L' c-char-sequence '
+///       c-char-sequence:
+///         c-char
+///         c-char-sequence c-char
+///       c-char:
+///         any member of the source character set except the single-quote ',
+///           backslash \, or new-line character
+///         escape-sequence
+///         universal-character-name
+///       escape-sequence:
+///         simple-escape-sequence
+///         octal-escape-sequence
+///         hexadecimal-escape-sequence
+///       simple-escape-sequence:
+///         one of \' \" \? \\ \a \b \f \n \r \t \v
+///       octal-escape-sequence:
+///         \ octal-digit
+///         \ octal-digit octal-digit
+///         \ octal-digit octal-digit octal-digit
+///       hexadecimal-escape-sequence:
+///         \x hexadecimal-digit
+///         hexadecimal-escape-sequence hexadecimal-digit
+///       universal-character-name: [C++11 lex.charset]
+///         \u hex-quad
+///         \U hex-quad hex-quad
+///       hex-quad:
+///         hex-digit hex-digit hex-digit hex-digit
+///
+CharLiteralParser::CharLiteralParser(const char *begin, const char *end,
+                                     SourceLocation Loc, Preprocessor &PP,
+                                     tok::TokenKind kind) {
+  // At this point we know that the character matches the regex "(L|u|U)?'.*'".
+  HadError = false;
+
+  Kind = kind;
+
+  const char *TokBegin = begin;
+
+  // Skip over wide character determinant.
+  if (Kind != tok::char_constant) {
+    ++begin;
+  }
+
+  // Skip over the entry quote.
+  assert(begin[0] == '\'' && "Invalid token lexed");
+  ++begin;
+
+  // Remove an optional ud-suffix.
+  if (end[-1] != '\'') {
+    const char *UDSuffixEnd = end;
+    do {
+      --end;
+    } while (end[-1] != '\'');
+    UDSuffixBuf.assign(end, UDSuffixEnd);
+    UDSuffixOffset = end - TokBegin;
+  }
+
+  // Trim the ending quote.
+  assert(end != begin && "Invalid token lexed");
+  --end;
+
+  // FIXME: The "Value" is an uint64_t so we can handle char literals of
+  // up to 64-bits.
+  // FIXME: This extensively assumes that 'char' is 8-bits.
+  assert(PP.getTargetInfo().getCharWidth() == 8 &&
+         "Assumes char is 8 bits");
+  assert(PP.getTargetInfo().getIntWidth() <= 64 &&
+         (PP.getTargetInfo().getIntWidth() & 7) == 0 &&
+         "Assumes sizeof(int) on target is <= 64 and a multiple of char");
+  assert(PP.getTargetInfo().getWCharWidth() <= 64 &&
+         "Assumes sizeof(wchar) on target is <= 64");
+
+  SmallVector<uint32_t,4> codepoint_buffer;
+  codepoint_buffer.resize(end-begin);
+  uint32_t *buffer_begin = &codepoint_buffer.front();
+  uint32_t *buffer_end = buffer_begin + codepoint_buffer.size();
+
+  // Unicode escapes representing characters that cannot be correctly
+  // represented in a single code unit are disallowed in character literals
+  // by this implementation.
+  uint32_t largest_character_for_kind;
+  if (tok::wide_char_constant == Kind) {
+    largest_character_for_kind = 0xFFFFFFFFu >> (32-PP.getTargetInfo().getWCharWidth());
+  } else if (tok::utf16_char_constant == Kind) {
+    largest_character_for_kind = 0xFFFF;
+  } else if (tok::utf32_char_constant == Kind) {
+    largest_character_for_kind = 0x10FFFF;
+  } else {
+    largest_character_for_kind = 0x7Fu;
+  }
+
+  while (begin!=end) {
+    // Is this a span of non-escape characters?
+    if (begin[0] != '\\') {
+      char const *start = begin;
+      do {
+        ++begin;
+      } while (begin != end && *begin != '\\');
+
+      char const *tmp_in_start = start;
+      uint32_t *tmp_out_start = buffer_begin;
+      ConversionResult res =
+      ConvertUTF8toUTF32(reinterpret_cast<UTF8 const **>(&start),
+                         reinterpret_cast<UTF8 const *>(begin),
+                         &buffer_begin,buffer_end,strictConversion);
+      if (res!=conversionOK) {
+        // If we see bad encoding for unprefixed character literals, warn and 
+        // simply copy the byte values, for compatibility with gcc and 
+        // older versions of clang.
+        bool NoErrorOnBadEncoding = isAscii();
+        unsigned Msg = diag::err_bad_character_encoding;
+        if (NoErrorOnBadEncoding)
+          Msg = diag::warn_bad_character_encoding;
+        PP.Diag(Loc, Msg);
+        if (NoErrorOnBadEncoding) {
+          start = tmp_in_start;
+          buffer_begin = tmp_out_start;
+          for ( ; start != begin; ++start, ++buffer_begin)
+            *buffer_begin = static_cast<uint8_t>(*start);
+        } else {
+          HadError = true;
+        }
+      } else {
+        for (; tmp_out_start <buffer_begin; ++tmp_out_start) {
+          if (*tmp_out_start > largest_character_for_kind) {
+            HadError = true;
+            PP.Diag(Loc, diag::err_character_too_large);
+          }
+        }
+      }
+
+      continue;
+    }
+    // Is this a Universal Character Name excape?
+    if (begin[1] == 'u' || begin[1] == 'U') {
+      unsigned short UcnLen = 0;
+      if (!ProcessUCNEscape(TokBegin, begin, end, *buffer_begin, UcnLen,
+                            FullSourceLoc(Loc, PP.getSourceManager()),
+                            &PP.getDiagnostics(), PP.getLangOpts(),
+                            true))
+      {
+        HadError = true;
+      } else if (*buffer_begin > largest_character_for_kind) {
+        HadError = true;
+        PP.Diag(Loc,diag::err_character_too_large);
+      }
+
+      ++buffer_begin;
+      continue;
+    }
+    unsigned CharWidth = getCharWidth(Kind, PP.getTargetInfo());
+    uint64_t result =
+    ProcessCharEscape(begin, end, HadError,
+                      FullSourceLoc(Loc,PP.getSourceManager()),
+                      CharWidth, &PP.getDiagnostics());
+    *buffer_begin++ = result;
+  }
+
+  unsigned NumCharsSoFar = buffer_begin-&codepoint_buffer.front();
+
+  if (NumCharsSoFar > 1) {
+    if (isWide())
+      PP.Diag(Loc, diag::warn_extraneous_char_constant);
+    else if (isAscii() && NumCharsSoFar == 4)
+      PP.Diag(Loc, diag::ext_four_char_character_literal);
+    else if (isAscii())
+      PP.Diag(Loc, diag::ext_multichar_character_literal);
+    else
+      PP.Diag(Loc, diag::err_multichar_utf_character_literal);
+    IsMultiChar = true;
+  } else
+    IsMultiChar = false;
+
+  llvm::APInt LitVal(PP.getTargetInfo().getIntWidth(), 0);
+
+  // Narrow character literals act as though their value is concatenated
+  // in this implementation, but warn on overflow.
+  bool multi_char_too_long = false;
+  if (isAscii() && isMultiChar()) {
+    LitVal = 0;
+    for (size_t i=0;i<NumCharsSoFar;++i) {
+      // check for enough leading zeros to shift into
+      multi_char_too_long |= (LitVal.countLeadingZeros() < 8);
+      LitVal <<= 8;
+      LitVal = LitVal + (codepoint_buffer[i] & 0xFF);
+    }
+  } else if (NumCharsSoFar > 0) {
+    // otherwise just take the last character
+    LitVal = buffer_begin[-1];
+  }
+
+  if (!HadError && multi_char_too_long) {
+    PP.Diag(Loc,diag::warn_char_constant_too_large);
+  }
+
+  // Transfer the value from APInt to uint64_t
+  Value = LitVal.getZExtValue();
+
+  // If this is a single narrow character, sign extend it (e.g. '\xFF' is "-1")
+  // if 'char' is signed for this target (C99 6.4.4.4p10).  Note that multiple
+  // character constants are not sign extended in the this implementation:
+  // '\xFF\xFF' = 65536 and '\x0\xFF' = 255, which matches GCC.
+  if (isAscii() && NumCharsSoFar == 1 && (Value & 128) &&
+      PP.getLangOpts().CharIsSigned)
+    Value = (signed char)Value;
+}
+
+
+///       string-literal: [C++0x lex.string]
+///         encoding-prefix " [s-char-sequence] "
+///         encoding-prefix R raw-string
+///       encoding-prefix:
+///         u8
+///         u
+///         U
+///         L
+///       s-char-sequence:
+///         s-char
+///         s-char-sequence s-char
+///       s-char:
+///         any member of the source character set except the double-quote ",
+///           backslash \, or new-line character
+///         escape-sequence
+///         universal-character-name
+///       raw-string:
+///         " d-char-sequence ( r-char-sequence ) d-char-sequence "
+///       r-char-sequence:
+///         r-char
+///         r-char-sequence r-char
+///       r-char:
+///         any member of the source character set, except a right parenthesis )
+///           followed by the initial d-char-sequence (which may be empty)
+///           followed by a double quote ".
+///       d-char-sequence:
+///         d-char
+///         d-char-sequence d-char
+///       d-char:
+///         any member of the basic source character set except:
+///           space, the left parenthesis (, the right parenthesis ),
+///           the backslash \, and the control characters representing horizontal
+///           tab, vertical tab, form feed, and newline.
+///       escape-sequence: [C++0x lex.ccon]
+///         simple-escape-sequence
+///         octal-escape-sequence
+///         hexadecimal-escape-sequence
+///       simple-escape-sequence:
+///         one of \' \" \? \\ \a \b \f \n \r \t \v
+///       octal-escape-sequence:
+///         \ octal-digit
+///         \ octal-digit octal-digit
+///         \ octal-digit octal-digit octal-digit
+///       hexadecimal-escape-sequence:
+///         \x hexadecimal-digit
+///         hexadecimal-escape-sequence hexadecimal-digit
+///       universal-character-name:
+///         \u hex-quad
+///         \U hex-quad hex-quad
+///       hex-quad:
+///         hex-digit hex-digit hex-digit hex-digit
+///
+StringLiteralParser::
+StringLiteralParser(const Token *StringToks, unsigned NumStringToks,
+                    Preprocessor &PP, bool Complain)
+  : SM(PP.getSourceManager()), Features(PP.getLangOpts()),
+    Target(PP.getTargetInfo()), Diags(Complain ? &PP.getDiagnostics() : 0),
+    MaxTokenLength(0), SizeBound(0), CharByteWidth(0), Kind(tok::unknown),
+    ResultPtr(ResultBuf.data()), hadError(false), Pascal(false) {
+  init(StringToks, NumStringToks);
+}
+
+void StringLiteralParser::init(const Token *StringToks, unsigned NumStringToks){
+  // The literal token may have come from an invalid source location (e.g. due
+  // to a PCH error), in which case the token length will be 0.
+  if (NumStringToks == 0 || StringToks[0].getLength() < 2) {
+    hadError = true;
+    return;
+  }
+
+  // Scan all of the string portions, remember the max individual token length,
+  // computing a bound on the concatenated string length, and see whether any
+  // piece is a wide-string.  If any of the string portions is a wide-string
+  // literal, the result is a wide-string literal [C99 6.4.5p4].
+  assert(NumStringToks && "expected at least one token");
+  MaxTokenLength = StringToks[0].getLength();
+  assert(StringToks[0].getLength() >= 2 && "literal token is invalid!");
+  SizeBound = StringToks[0].getLength()-2;  // -2 for "".
+  Kind = StringToks[0].getKind();
+
+  hadError = false;
+
+  // Implement Translation Phase #6: concatenation of string literals
+  /// (C99 5.1.1.2p1).  The common case is only one string fragment.
+  for (unsigned i = 1; i != NumStringToks; ++i) {
+    if (StringToks[i].getLength() < 2) {
+      hadError = true;
+      return;
+    }
+
+    // The string could be shorter than this if it needs cleaning, but this is a
+    // reasonable bound, which is all we need.
+    assert(StringToks[i].getLength() >= 2 && "literal token is invalid!");
+    SizeBound += StringToks[i].getLength()-2;  // -2 for "".
+
+    // Remember maximum string piece length.
+    if (StringToks[i].getLength() > MaxTokenLength)
+      MaxTokenLength = StringToks[i].getLength();
+
+    // Remember if we see any wide or utf-8/16/32 strings.
+    // Also check for illegal concatenations.
+    if (StringToks[i].isNot(Kind) && StringToks[i].isNot(tok::string_literal)) {
+      if (isAscii()) {
+        Kind = StringToks[i].getKind();
+      } else {
+        if (Diags)
+          Diags->Report(FullSourceLoc(StringToks[i].getLocation(), SM),
+                        diag::err_unsupported_string_concat);
+        hadError = true;
+      }
+    }
+  }
+
+  // Include space for the null terminator.
+  ++SizeBound;
+
+  // TODO: K&R warning: "traditional C rejects string constant concatenation"
+
+  // Get the width in bytes of char/wchar_t/char16_t/char32_t
+  CharByteWidth = getCharWidth(Kind, Target);
+  assert((CharByteWidth & 7) == 0 && "Assumes character size is byte multiple");
+  CharByteWidth /= 8;
+
+  // The output buffer size needs to be large enough to hold wide characters.
+  // This is a worst-case assumption which basically corresponds to L"" "long".
+  SizeBound *= CharByteWidth;
+
+  // Size the temporary buffer to hold the result string data.
+  ResultBuf.resize(SizeBound);
+
+  // Likewise, but for each string piece.
+  SmallString<512> TokenBuf;
+  TokenBuf.resize(MaxTokenLength);
+
+  // Loop over all the strings, getting their spelling, and expanding them to
+  // wide strings as appropriate.
+  ResultPtr = &ResultBuf[0];   // Next byte to fill in.
+
+  Pascal = false;
+
+  SourceLocation UDSuffixTokLoc;
+
+  for (unsigned i = 0, e = NumStringToks; i != e; ++i) {
+    const char *ThisTokBuf = &TokenBuf[0];
+    // Get the spelling of the token, which eliminates trigraphs, etc.  We know
+    // that ThisTokBuf points to a buffer that is big enough for the whole token
+    // and 'spelled' tokens can only shrink.
+    bool StringInvalid = false;
+    unsigned ThisTokLen = 
+      Lexer::getSpelling(StringToks[i], ThisTokBuf, SM, Features,
+                         &StringInvalid);
+    if (StringInvalid) {
+      hadError = true;
+      continue;
+    }
+
+    const char *ThisTokBegin = ThisTokBuf;
+    const char *ThisTokEnd = ThisTokBuf+ThisTokLen;
+
+    // Remove an optional ud-suffix.
+    if (ThisTokEnd[-1] != '"') {
+      const char *UDSuffixEnd = ThisTokEnd;
+      do {
+        --ThisTokEnd;
+      } while (ThisTokEnd[-1] != '"');
+
+      StringRef UDSuffix(ThisTokEnd, UDSuffixEnd - ThisTokEnd);
+
+      if (UDSuffixBuf.empty()) {
+        UDSuffixBuf.assign(UDSuffix);
+        UDSuffixToken = i;
+        UDSuffixOffset = ThisTokEnd - ThisTokBuf;
+        UDSuffixTokLoc = StringToks[i].getLocation();
+      } else if (!UDSuffixBuf.equals(UDSuffix)) {
+        // C++11 [lex.ext]p8: At the end of phase 6, if a string literal is the
+        // result of a concatenation involving at least one user-defined-string-
+        // literal, all the participating user-defined-string-literals shall
+        // have the same ud-suffix.
+        if (Diags) {
+          SourceLocation TokLoc = StringToks[i].getLocation();
+          Diags->Report(TokLoc, diag::err_string_concat_mixed_suffix)
+            << UDSuffixBuf << UDSuffix
+            << SourceRange(UDSuffixTokLoc, UDSuffixTokLoc)
+            << SourceRange(TokLoc, TokLoc);
+        }
+        hadError = true;
+      }
+    }
+
+    // Strip the end quote.
+    --ThisTokEnd;
+
+    // TODO: Input character set mapping support.
+
+    // Skip marker for wide or unicode strings.
+    if (ThisTokBuf[0] == 'L' || ThisTokBuf[0] == 'u' || ThisTokBuf[0] == 'U') {
+      ++ThisTokBuf;
+      // Skip 8 of u8 marker for utf8 strings.
+      if (ThisTokBuf[0] == '8')
+        ++ThisTokBuf;
+    }
+
+    // Check for raw string
+    if (ThisTokBuf[0] == 'R') {
+      ThisTokBuf += 2; // skip R"
+
+      const char *Prefix = ThisTokBuf;
+      while (ThisTokBuf[0] != '(')
+        ++ThisTokBuf;
+      ++ThisTokBuf; // skip '('
+
+      // Remove same number of characters from the end
+      ThisTokEnd -= ThisTokBuf - Prefix;
+      assert(ThisTokEnd >= ThisTokBuf && "malformed raw string literal");
+
+      // Copy the string over
+      if (CopyStringFragment(StringRef(ThisTokBuf, ThisTokEnd - ThisTokBuf)))
+        if (DiagnoseBadString(StringToks[i]))
+          hadError = true;
+    } else {
+      assert(ThisTokBuf[0] == '"' && "Expected quote, lexer broken?");
+      ++ThisTokBuf; // skip "
+
+      // Check if this is a pascal string
+      if (Features.PascalStrings && ThisTokBuf + 1 != ThisTokEnd &&
+          ThisTokBuf[0] == '\\' && ThisTokBuf[1] == 'p') {
+
+        // If the \p sequence is found in the first token, we have a pascal string
+        // Otherwise, if we already have a pascal string, ignore the first \p
+        if (i == 0) {
+          ++ThisTokBuf;
+          Pascal = true;
+        } else if (Pascal)
+          ThisTokBuf += 2;
+      }
+
+      while (ThisTokBuf != ThisTokEnd) {
+        // Is this a span of non-escape characters?
+        if (ThisTokBuf[0] != '\\') {
+          const char *InStart = ThisTokBuf;
+          do {
+            ++ThisTokBuf;
+          } while (ThisTokBuf != ThisTokEnd && ThisTokBuf[0] != '\\');
+
+          // Copy the character span over.
+          if (CopyStringFragment(StringRef(InStart, ThisTokBuf - InStart)))
+            if (DiagnoseBadString(StringToks[i]))
+              hadError = true;
+          continue;
+        }
+        // Is this a Universal Character Name escape?
+        if (ThisTokBuf[1] == 'u' || ThisTokBuf[1] == 'U') {
+          EncodeUCNEscape(ThisTokBegin, ThisTokBuf, ThisTokEnd,
+                          ResultPtr, hadError,
+                          FullSourceLoc(StringToks[i].getLocation(), SM),
+                          CharByteWidth, Diags, Features);
+          continue;
+        }
+        // Otherwise, this is a non-UCN escape character.  Process it.
+        unsigned ResultChar =
+          ProcessCharEscape(ThisTokBuf, ThisTokEnd, hadError,
+                            FullSourceLoc(StringToks[i].getLocation(), SM),
+                            CharByteWidth*8, Diags);
+
+        if (CharByteWidth == 4) {
+          // FIXME: Make the type of the result buffer correct instead of
+          // using reinterpret_cast.
+          UTF32 *ResultWidePtr = reinterpret_cast<UTF32*>(ResultPtr);
+          *ResultWidePtr = ResultChar;
+          ResultPtr += 4;
+        } else if (CharByteWidth == 2) {
+          // FIXME: Make the type of the result buffer correct instead of
+          // using reinterpret_cast.
+          UTF16 *ResultWidePtr = reinterpret_cast<UTF16*>(ResultPtr);
+          *ResultWidePtr = ResultChar & 0xFFFF;
+          ResultPtr += 2;
+        } else {
+          assert(CharByteWidth == 1 && "Unexpected char width");
+          *ResultPtr++ = ResultChar & 0xFF;
+        }
+      }
+    }
+  }
+
+  if (Pascal) {
+    if (CharByteWidth == 4) {
+      // FIXME: Make the type of the result buffer correct instead of
+      // using reinterpret_cast.
+      UTF32 *ResultWidePtr = reinterpret_cast<UTF32*>(ResultBuf.data());
+      ResultWidePtr[0] = GetNumStringChars() - 1;
+    } else if (CharByteWidth == 2) {
+      // FIXME: Make the type of the result buffer correct instead of
+      // using reinterpret_cast.
+      UTF16 *ResultWidePtr = reinterpret_cast<UTF16*>(ResultBuf.data());
+      ResultWidePtr[0] = GetNumStringChars() - 1;
+    } else {
+      assert(CharByteWidth == 1 && "Unexpected char width");
+      ResultBuf[0] = GetNumStringChars() - 1;
+    }
+
+    // Verify that pascal strings aren't too large.
+    if (GetStringLength() > 256) {
+      if (Diags) 
+        Diags->Report(FullSourceLoc(StringToks[0].getLocation(), SM),
+                      diag::err_pascal_string_too_long)
+          << SourceRange(StringToks[0].getLocation(),
+                         StringToks[NumStringToks-1].getLocation());
+      hadError = true;
+      return;
+    }
+  } else if (Diags) {
+    // Complain if this string literal has too many characters.
+    unsigned MaxChars = Features.CPlusPlus? 65536 : Features.C99 ? 4095 : 509;
+    
+    if (GetNumStringChars() > MaxChars)
+      Diags->Report(FullSourceLoc(StringToks[0].getLocation(), SM),
+                    diag::ext_string_too_long)
+        << GetNumStringChars() << MaxChars
+        << (Features.CPlusPlus ? 2 : Features.C99 ? 1 : 0)
+        << SourceRange(StringToks[0].getLocation(),
+                       StringToks[NumStringToks-1].getLocation());
+  }
+}
+
+
+/// copyStringFragment - This function copies from Start to End into ResultPtr.
+/// Performs widening for multi-byte characters.
+bool StringLiteralParser::CopyStringFragment(StringRef Fragment) {
+  assert(CharByteWidth==1 || CharByteWidth==2 || CharByteWidth==4);
+  ConversionResult result = conversionOK;
+  // Copy the character span over.
+  if (CharByteWidth == 1) {
+    if (!isLegalUTF8String(reinterpret_cast<const UTF8*>(Fragment.begin()),
+                           reinterpret_cast<const UTF8*>(Fragment.end())))
+      result = sourceIllegal;
+    memcpy(ResultPtr, Fragment.data(), Fragment.size());
+    ResultPtr += Fragment.size();
+  } else if (CharByteWidth == 2) {
+    UTF8 const *sourceStart = (UTF8 const *)Fragment.data();
+    // FIXME: Make the type of the result buffer correct instead of
+    // using reinterpret_cast.
+    UTF16 *targetStart = reinterpret_cast<UTF16*>(ResultPtr);
+    ConversionFlags flags = strictConversion;
+    result = ConvertUTF8toUTF16(
+	    &sourceStart,sourceStart + Fragment.size(),
+        &targetStart,targetStart + 2*Fragment.size(),flags);
+    if (result==conversionOK)
+      ResultPtr = reinterpret_cast<char*>(targetStart);
+  } else if (CharByteWidth == 4) {
+    UTF8 const *sourceStart = (UTF8 const *)Fragment.data();
+    // FIXME: Make the type of the result buffer correct instead of
+    // using reinterpret_cast.
+    UTF32 *targetStart = reinterpret_cast<UTF32*>(ResultPtr);
+    ConversionFlags flags = strictConversion;
+    result = ConvertUTF8toUTF32(
+        &sourceStart,sourceStart + Fragment.size(),
+        &targetStart,targetStart + 4*Fragment.size(),flags);
+    if (result==conversionOK)
+      ResultPtr = reinterpret_cast<char*>(targetStart);
+  }
+  assert((result != targetExhausted)
+         && "ConvertUTF8toUTFXX exhausted target buffer");
+  return result != conversionOK;
+}
+
+bool StringLiteralParser::DiagnoseBadString(const Token &Tok) {
+  // If we see bad encoding for unprefixed string literals, warn and
+  // simply copy the byte values, for compatibility with gcc and older
+  // versions of clang.
+  bool NoErrorOnBadEncoding = isAscii();
+  unsigned Msg = NoErrorOnBadEncoding ? diag::warn_bad_string_encoding :
+                                        diag::err_bad_string_encoding;
+  if (Diags)
+    Diags->Report(FullSourceLoc(Tok.getLocation(), SM), Msg);
+  return !NoErrorOnBadEncoding;
+}
+
+/// getOffsetOfStringByte - This function returns the offset of the
+/// specified byte of the string data represented by Token.  This handles
+/// advancing over escape sequences in the string.
+unsigned StringLiteralParser::getOffsetOfStringByte(const Token &Tok,
+                                                    unsigned ByteNo) const {
+  // Get the spelling of the token.
+  SmallString<32> SpellingBuffer;
+  SpellingBuffer.resize(Tok.getLength());
+
+  bool StringInvalid = false;
+  const char *SpellingPtr = &SpellingBuffer[0];
+  unsigned TokLen = Lexer::getSpelling(Tok, SpellingPtr, SM, Features,
+                                       &StringInvalid);
+  if (StringInvalid)
+    return 0;
+
+  assert(SpellingPtr[0] != 'L' && SpellingPtr[0] != 'u' &&
+         SpellingPtr[0] != 'U' && "Doesn't handle wide or utf strings yet");
+
+
+  const char *SpellingStart = SpellingPtr;
+  const char *SpellingEnd = SpellingPtr+TokLen;
+
+  // Skip over the leading quote.
+  assert(SpellingPtr[0] == '"' && "Should be a string literal!");
+  ++SpellingPtr;
+
+  // Skip over bytes until we find the offset we're looking for.
+  while (ByteNo) {
+    assert(SpellingPtr < SpellingEnd && "Didn't find byte offset!");
+
+    // Step over non-escapes simply.
+    if (*SpellingPtr != '\\') {
+      ++SpellingPtr;
+      --ByteNo;
+      continue;
+    }
+
+    // Otherwise, this is an escape character.  Advance over it.
+    bool HadError = false;
+    ProcessCharEscape(SpellingPtr, SpellingEnd, HadError,
+                      FullSourceLoc(Tok.getLocation(), SM),
+                      CharByteWidth*8, Diags);
+    assert(!HadError && "This method isn't valid on erroneous strings");
+    --ByteNo;
+  }
+
+  return SpellingPtr-SpellingStart;
+}