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Diffstat (limited to 'contrib/llvm/tools/clang/lib/Lex/Lexer.cpp')
| -rw-r--r-- | contrib/llvm/tools/clang/lib/Lex/Lexer.cpp | 3892 | 
1 files changed, 3892 insertions, 0 deletions
diff --git a/contrib/llvm/tools/clang/lib/Lex/Lexer.cpp b/contrib/llvm/tools/clang/lib/Lex/Lexer.cpp new file mode 100644 index 000000000000..e8588a771a43 --- /dev/null +++ b/contrib/llvm/tools/clang/lib/Lex/Lexer.cpp @@ -0,0 +1,3892 @@ +//===- 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. +// +//===----------------------------------------------------------------------===// + +#include "clang/Lex/Lexer.h" +#include "UnicodeCharSets.h" +#include "clang/Basic/CharInfo.h" +#include "clang/Basic/IdentifierTable.h" +#include "clang/Basic/LangOptions.h" +#include "clang/Basic/SourceLocation.h" +#include "clang/Basic/SourceManager.h" +#include "clang/Basic/TokenKinds.h" +#include "clang/Lex/LexDiagnostic.h" +#include "clang/Lex/LiteralSupport.h" +#include "clang/Lex/MultipleIncludeOpt.h" +#include "clang/Lex/Preprocessor.h" +#include "clang/Lex/PreprocessorOptions.h" +#include "clang/Lex/Token.h" +#include "clang/Basic/Diagnostic.h" +#include "clang/Basic/LLVM.h" +#include "clang/Basic/TokenKinds.h" +#include "llvm/ADT/None.h" +#include "llvm/ADT/Optional.h" +#include "llvm/ADT/StringExtras.h" +#include "llvm/ADT/StringSwitch.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/Support/Compiler.h" +#include "llvm/Support/ConvertUTF.h" +#include "llvm/Support/MathExtras.h" +#include "llvm/Support/MemoryBuffer.h" +#include "llvm/Support/NativeFormatting.h" +#include "llvm/Support/UnicodeCharRanges.h" +#include <algorithm> +#include <cassert> +#include <cstddef> +#include <cstdint> +#include <cstring> +#include <string> +#include <tuple> +#include <utility> + +using namespace clang; + +//===----------------------------------------------------------------------===// +// Token Class Implementation +//===----------------------------------------------------------------------===// + +/// isObjCAtKeyword - Return true if we have an ObjC keyword identifier. +bool Token::isObjCAtKeyword(tok::ObjCKeywordKind objcKey) const { +  if (isAnnotation()) +    return false; +  if (IdentifierInfo *II = getIdentifierInfo()) +    return II->getObjCKeywordID() == objcKey; +  return false; +} + +/// getObjCKeywordID - Return the ObjC keyword kind. +tok::ObjCKeywordKind Token::getObjCKeywordID() const { +  if (isAnnotation()) +    return tok::objc_not_keyword; +  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) { +  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; +  IsAtPhysicalStartOfLine = true; + +  HasLeadingSpace = false; +  HasLeadingEmptyMacro = false; + +  // 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()); + +  resetExtendedTokenMode(); +} + +/// Lexer constructor - Create a new raw lexer object.  This object is only +/// suitable for calls to 'LexFromRawLexer'.  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 'LexFromRawLexer'.  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) +    : Lexer(SM.getLocForStartOfFile(FID), langOpts, FromFile->getBufferStart(), +            FromFile->getBufferStart(), FromFile->getBufferEnd()) {} + +void Lexer::resetExtendedTokenMode() { +  assert(PP && "Cannot reset token mode without a preprocessor"); +  if (LangOpts.TraditionalCPP) +    SetKeepWhitespaceMode(true); +  else +    SetCommentRetentionState(PP->getCommentRetentionState()); +} + +/// 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". +/// +/// TODO: 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; +} + +template <typename T> static void StringifyImpl(T &Str, char Quote) { +  typename T::size_type i = 0, e = Str.size(); +  while (i < e) { +    if (Str[i] == '\\' || Str[i] == Quote) { +      Str.insert(Str.begin() + i, '\\'); +      i += 2; +      ++e; +    } else if (Str[i] == '\n' || Str[i] == '\r') { +      // Replace '\r\n' and '\n\r' to '\\' followed by 'n'. +      if ((i < e - 1) && (Str[i + 1] == '\n' || Str[i + 1] == '\r') && +          Str[i] != Str[i + 1]) { +        Str[i] = '\\'; +        Str[i + 1] = 'n'; +      } else { +        // Replace '\n' and '\r' to '\\' followed by 'n'. +        Str[i] = '\\'; +        Str.insert(Str.begin() + i + 1, 'n'); +        ++e; +      } +      i += 2; +    } else +      ++i; +  } +} + +std::string Lexer::Stringify(StringRef Str, bool Charify) { +  std::string Result = Str; +  char Quote = Charify ? '\'' : '"'; +  StringifyImpl(Result, Quote); +  return Result; +} + +void Lexer::Stringify(SmallVectorImpl<char> &Str) { StringifyImpl(Str, '"'); } + +//===----------------------------------------------------------------------===// +// Token Spelling +//===----------------------------------------------------------------------===// + +/// Slow case of getSpelling. Extract the characters comprising the +/// spelling of this token from the provided input buffer. +static size_t getSpellingSlow(const Token &Tok, const char *BufPtr, +                              const LangOptions &LangOpts, char *Spelling) { +  assert(Tok.needsCleaning() && "getSpellingSlow called on simple token"); + +  size_t Length = 0; +  const char *BufEnd = BufPtr + Tok.getLength(); + +  if (tok::isStringLiteral(Tok.getKind())) { +    // Munch the encoding-prefix and opening double-quote. +    while (BufPtr < BufEnd) { +      unsigned Size; +      Spelling[Length++] = Lexer::getCharAndSizeNoWarn(BufPtr, Size, LangOpts); +      BufPtr += Size; + +      if (Spelling[Length - 1] == '"') +        break; +    } + +    // Raw string literals need special handling; trigraph expansion and line +    // splicing do not occur within their d-char-sequence nor within their +    // r-char-sequence. +    if (Length >= 2 && +        Spelling[Length - 2] == 'R' && Spelling[Length - 1] == '"') { +      // Search backwards from the end of the token to find the matching closing +      // quote. +      const char *RawEnd = BufEnd; +      do --RawEnd; while (*RawEnd != '"'); +      size_t RawLength = RawEnd - BufPtr + 1; + +      // Everything between the quotes is included verbatim in the spelling. +      memcpy(Spelling + Length, BufPtr, RawLength); +      Length += RawLength; +      BufPtr += RawLength; + +      // The rest of the token is lexed normally. +    } +  } + +  while (BufPtr < BufEnd) { +    unsigned Size; +    Spelling[Length++] = Lexer::getCharAndSizeNoWarn(BufPtr, Size, LangOpts); +    BufPtr += Size; +  } + +  assert(Length < Tok.getLength() && +         "NeedsCleaning flag set on token that didn't need cleaning!"); +  return Length; +} + +/// 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 {}; +  } + +  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.resize(length); +  buffer.resize(getSpellingSlow(token, tokenBegin, options, buffer.data())); +  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!"); + +  bool CharDataInvalid = false; +  const char *TokStart = SourceMgr.getCharacterData(Tok.getLocation(), +                                                    &CharDataInvalid); +  if (Invalid) +    *Invalid = CharDataInvalid; +  if (CharDataInvalid) +    return {}; + +  // If this token contains nothing interesting, return it directly. +  if (!Tok.needsCleaning()) +    return std::string(TokStart, TokStart + Tok.getLength()); + +  std::string Result; +  Result.resize(Tok.getLength()); +  Result.resize(getSpellingSlow(Tok, TokStart, LangOpts, &*Result.begin())); +  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 = nullptr; +  // NOTE: this has to be checked *before* testing for an IdentifierInfo. +  if (Tok.is(tok::raw_identifier)) +    TokStart = Tok.getRawIdentifier().data(); +  else if (!Tok.hasUCN()) { +    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) { +    // 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. +  return getSpellingSlow(Tok, TokStart, LangOpts, const_cast<char*>(Buffer)); +} + +/// 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) { +  Token TheTok; +  if (getRawToken(Loc, TheTok, SM, LangOpts)) +    return 0; +  return TheTok.getLength(); +} + +/// Relex the token at the specified location. +/// \returns true if there was a failure, false on success. +bool Lexer::getRawToken(SourceLocation Loc, Token &Result, +                        const SourceManager &SM, +                        const LangOptions &LangOpts, +                        bool IgnoreWhiteSpace) { +  // 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 true; + +  const char *StrData = Buffer.data()+LocInfo.second; + +  if (!IgnoreWhiteSpace && isWhitespace(StrData[0])) +    return true; + +  // 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); +  TheLexer.LexFromRawLexer(Result); +  return false; +} + +/// Returns the pointer that points to the beginning of line that contains +/// the given offset, or null if the offset if invalid. +static const char *findBeginningOfLine(StringRef Buffer, unsigned Offset) { +  const char *BufStart = Buffer.data(); +  if (Offset >= Buffer.size()) +    return nullptr; + +  const char *LexStart = BufStart + Offset; +  for (; LexStart != BufStart; --LexStart) { +    if (isVerticalWhitespace(LexStart[0]) && +        !Lexer::isNewLineEscaped(BufStart, LexStart)) { +      // LexStart should point at first character of logical line. +      ++LexStart; +      break; +    } +  } +  return LexStart; +} + +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 *StrData = Buffer.data() + LocInfo.second; +  const char *LexStart = findBeginningOfLine(Buffer, LocInfo.second); +  if (!LexStart || LexStart == StrData) +    return Loc; + +  // Create a lexer starting at the beginning of this token. +  SourceLocation LexerStartLoc = Loc.getLocWithOffset(-LocInfo.second); +  Lexer TheLexer(LexerStartLoc, LangOpts, Buffer.data(), 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_Unknown +}; + +} // namespace + +PreambleBounds Lexer::ComputePreamble(StringRef 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 FileLoc = SourceLocation::getFromRawEncoding(StartOffset); +  Lexer TheLexer(FileLoc, LangOpts, Buffer.begin(), Buffer.begin(), +                 Buffer.end()); +  TheLexer.SetCommentRetentionState(true); + +  bool InPreprocessorDirective = false; +  Token TheTok; +  SourceLocation ActiveCommentLoc; + +  unsigned MaxLineOffset = 0; +  if (MaxLines) { +    const char *CurPtr = Buffer.begin(); +    unsigned CurLine = 0; +    while (CurPtr != Buffer.end()) { +      char ch = *CurPtr++; +      if (ch == '\n') { +        ++CurLine; +        if (CurLine == MaxLines) +          break; +      } +    } +    if (CurPtr != Buffer.end()) +      MaxLineOffset = CurPtr - Buffer.begin(); +  } + +  do { +    TheLexer.LexFromRawLexer(TheTok); + +    if (InPreprocessorDirective) { +      // If we've hit the end of the file, we're done. +      if (TheTok.getKind() == tok::eof) { +        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) { +      if (ActiveCommentLoc.isInvalid()) +        ActiveCommentLoc = TheTok.getLocation(); +      continue; +    } + +    if (TheTok.isAtStartOfLine() && TheTok.getKind() == tok::hash) { +      // This is the start of a preprocessor directive. +      Token HashTok = TheTok; +      InPreprocessorDirective = true; +      ActiveCommentLoc = SourceLocation(); + +      // 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.getRawIdentifier(); +        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_Skipped) +              .Case("ifdef", PDK_Skipped) +              .Case("ifndef", PDK_Skipped) +              .Case("elif", PDK_Skipped) +              .Case("else", PDK_Skipped) +              .Case("endif", PDK_Skipped) +              .Default(PDK_Unknown); + +        switch (PDK) { +        case PDK_Skipped: +          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; +  if (ActiveCommentLoc.isValid()) +    End = ActiveCommentLoc; // don't truncate a decl comment. +  else +    End = TheTok.getLocation(); + +  return PreambleBounds(End.getRawEncoding() - FileLoc.getRawEncoding(), +                        TheTok.isAtStartOfLine()); +} + +unsigned Lexer::getTokenPrefixLength(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 0; + +  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 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 PhysOffset; +} + +/// 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 {}; + +  if (Loc.isMacroID()) { +    if (Offset > 0 || !isAtEndOfMacroExpansion(Loc, SM, LangOpts, &Loc)) +      return {}; // 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); +} + +/// 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"); + +  SourceLocation expansionLoc; +  if (!SM.isAtStartOfImmediateMacroExpansion(loc, &expansionLoc)) +    return false; + +  if (expansionLoc.isFileID()) { +    // No other macro expansions, this is the first. +    if (MacroBegin) +      *MacroBegin = expansionLoc; +    return true; +  } + +  return isAtStartOfMacroExpansion(expansionLoc, SM, LangOpts, MacroBegin); +} + +/// 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; + +  SourceLocation afterLoc = loc.getLocWithOffset(tokLen); +  SourceLocation expansionLoc; +  if (!SM.isAtEndOfImmediateMacroExpansion(afterLoc, &expansionLoc)) +    return false; + +  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 {}; +  } + +  // Break down the source locations. +  FileID FID; +  unsigned BeginOffs; +  std::tie(FID, BeginOffs) = SM.getDecomposedLoc(Begin); +  if (FID.isInvalid()) +    return {}; + +  unsigned EndOffs; +  if (!SM.isInFileID(End, FID, &EndOffs) || +      BeginOffs > EndOffs) +    return {}; + +  return CharSourceRange::getCharRange(Begin, End); +} + +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 {}; + +  if (Begin.isFileID() && End.isFileID()) +    return makeRangeFromFileLocs(Range, SM, LangOpts); + +  if (Begin.isMacroID() && End.isFileID()) { +    if (!isAtStartOfMacroExpansion(Begin, SM, LangOpts, &Begin)) +      return {}; +    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 {}; +    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); +  } + +  bool Invalid = false; +  const SrcMgr::SLocEntry &BeginEntry = SM.getSLocEntry(SM.getFileID(Begin), +                                                        &Invalid); +  if (Invalid) +    return {}; + +  if (BeginEntry.getExpansion().isMacroArgExpansion()) { +    const SrcMgr::SLocEntry &EndEntry = SM.getSLocEntry(SM.getFileID(End), +                                                        &Invalid); +    if (Invalid) +      return {}; + +    if (EndEntry.getExpansion().isMacroArgExpansion() && +        BeginEntry.getExpansion().getExpansionLocStart() == +            EndEntry.getExpansion().getExpansionLocStart()) { +      Range.setBegin(SM.getImmediateSpellingLoc(Begin)); +      Range.setEnd(SM.getImmediateSpellingLoc(End)); +      return makeFileCharRange(Range, SM, LangOpts); +    } +  } + +  return {}; +} + +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 {}; +  } + +  // Break down the source location. +  std::pair<FileID, unsigned> beginInfo = SM.getDecomposedLoc(Range.getBegin()); +  if (beginInfo.first.isInvalid()) { +    if (Invalid) *Invalid = true; +    return {}; +  } + +  unsigned EndOffs; +  if (!SM.isInFileID(Range.getEnd(), beginInfo.first, &EndOffs) || +      beginInfo.second > EndOffs) { +    if (Invalid) *Invalid = true; +    return {}; +  } + +  // Try to the load the file buffer. +  bool invalidTemp = false; +  StringRef file = SM.getBufferData(beginInfo.first, &invalidTemp); +  if (invalidTemp) { +    if (Invalid) *Invalid = true; +    return {}; +  } + +  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 reasonable to call this on macros"); + +  // Find the location of the immediate macro expansion. +  while (true) { +    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).getBegin(); +    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); +} + +StringRef Lexer::getImmediateMacroNameForDiagnostics( +    SourceLocation Loc, const SourceManager &SM, const LangOptions &LangOpts) { +  assert(Loc.isMacroID() && "Only reasonable to call this on macros"); +  // Walk past macro argument expanions. +  while (SM.isMacroArgExpansion(Loc)) +    Loc = SM.getImmediateExpansionRange(Loc).getBegin(); + +  // If the macro's spelling has no FileID, then it's actually a token paste +  // or stringization (or similar) and not a macro at all. +  if (!SM.getFileEntryForID(SM.getFileID(SM.getSpellingLoc(Loc)))) +    return {}; + +  // 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(SM.getImmediateExpansionRange(Loc).getBegin()); + +  // 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); +} + +bool Lexer::isIdentifierBodyChar(char c, const LangOptions &LangOpts) { +  return isIdentifierBody(c, LangOpts.DollarIdents); +} + +bool Lexer::isNewLineEscaped(const char *BufferStart, const char *Str) { +  assert(isVerticalWhitespace(Str[0])); +  if (Str - 1 < BufferStart) +    return false; + +  if ((Str[0] == '\n' && Str[-1] == '\r') || +      (Str[0] == '\r' && Str[-1] == '\n')) { +    if (Str - 2 < BufferStart) +      return false; +    --Str; +  } +  --Str; + +  // Rewind to first non-space character: +  while (Str > BufferStart && isHorizontalWhitespace(*Str)) +    --Str; + +  return *Str == '\\'; +} + +StringRef Lexer::getIndentationForLine(SourceLocation Loc, +                                       const SourceManager &SM) { +  if (Loc.isInvalid() || Loc.isMacroID()) +    return {}; +  std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(Loc); +  if (LocInfo.first.isInvalid()) +    return {}; +  bool Invalid = false; +  StringRef Buffer = SM.getBufferData(LocInfo.first, &Invalid); +  if (Invalid) +    return {}; +  const char *Line = findBeginningOfLine(Buffer, LocInfo.second); +  if (!Line) +    return {}; +  StringRef Rest = Buffer.substr(Line - Buffer.data()); +  size_t NumWhitespaceChars = Rest.find_first_not_of(" \t"); +  return NumWhitespaceChars == StringRef::npos +             ? "" +             : Rest.take_front(NumWhitespaceChars); +} + +//===----------------------------------------------------------------------===// +// 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. +  CharSourceRange II = SM.getImmediateExpansionRange(FileLoc); + +  return SM.createExpansionLoc(SpellingLoc, II.getBegin(), II.getEnd(), 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 (true) { +    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; +      // FIXME: Take LangOpts into account; the language might not +      // support trigraphs. +      AfterEscape = P+3; +    } else { +      return P; +    } + +    unsigned NewLineSize = Lexer::getEscapedNewLineSize(AfterEscape); +    if (NewLineSize == 0) return P; +    P = AfterEscape+NewLineSize; +  } +} + +Optional<Token> Lexer::findNextToken(SourceLocation Loc, +                                     const SourceManager &SM, +                                     const LangOptions &LangOpts) { +  if (Loc.isMacroID()) { +    if (!Lexer::isAtEndOfMacroExpansion(Loc, SM, LangOpts, &Loc)) +      return None; +  } +  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; +  StringRef File = SM.getBufferData(LocInfo.first, &InvalidTemp); +  if (InvalidTemp) +    return None; + +  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); +  return Tok; +} + +/// 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) { +  Optional<Token> Tok = findNextToken(Loc, SM, LangOpts); +  if (!Tok || Tok->isNot(TKind)) +    return {}; +  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++; +    } + +    // Skip \r, \n, \r\n, or \n\r +    if (C == '\n' || C == '\r') { +      char PrevC = C; +      C = *(++TokenEnd); +      NumWhitespaceChars++; +      if ((C == '\n' || C == '\r') && C != PrevC) +        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. +/// +/// 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; + +      // 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 : nullptr)) { +      // 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; + +      // 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. +//===----------------------------------------------------------------------===// + +/// Routine that indiscriminately sets the offset into the source file. +void Lexer::SetByteOffset(unsigned Offset, bool StartOfLine) { +  BufferPtr = BufferStart + Offset; +  if (BufferPtr > BufferEnd) +    BufferPtr = BufferEnd; +  // FIXME: What exactly does the StartOfLine bit mean?  There are two +  // possible meanings for the "start" of the line: the first token on the +  // unexpanded line, or the first token on the expanded line. +  IsAtStartOfLine = StartOfLine; +  IsAtPhysicalStartOfLine = StartOfLine; +} + +static bool isAllowedIDChar(uint32_t C, const LangOptions &LangOpts) { +  if (LangOpts.AsmPreprocessor) { +    return false; +  } else if (LangOpts.CPlusPlus11 || LangOpts.C11) { +    static const llvm::sys::UnicodeCharSet C11AllowedIDChars( +        C11AllowedIDCharRanges); +    return C11AllowedIDChars.contains(C); +  } else if (LangOpts.CPlusPlus) { +    static const llvm::sys::UnicodeCharSet CXX03AllowedIDChars( +        CXX03AllowedIDCharRanges); +    return CXX03AllowedIDChars.contains(C); +  } else { +    static const llvm::sys::UnicodeCharSet C99AllowedIDChars( +        C99AllowedIDCharRanges); +    return C99AllowedIDChars.contains(C); +  } +} + +static bool isAllowedInitiallyIDChar(uint32_t C, const LangOptions &LangOpts) { +  assert(isAllowedIDChar(C, LangOpts)); +  if (LangOpts.AsmPreprocessor) { +    return false; +  } else if (LangOpts.CPlusPlus11 || LangOpts.C11) { +    static const llvm::sys::UnicodeCharSet C11DisallowedInitialIDChars( +        C11DisallowedInitialIDCharRanges); +    return !C11DisallowedInitialIDChars.contains(C); +  } else if (LangOpts.CPlusPlus) { +    return true; +  } else { +    static const llvm::sys::UnicodeCharSet C99DisallowedInitialIDChars( +        C99DisallowedInitialIDCharRanges); +    return !C99DisallowedInitialIDChars.contains(C); +  } +} + +static inline CharSourceRange makeCharRange(Lexer &L, const char *Begin, +                                            const char *End) { +  return CharSourceRange::getCharRange(L.getSourceLocation(Begin), +                                       L.getSourceLocation(End)); +} + +static void maybeDiagnoseIDCharCompat(DiagnosticsEngine &Diags, uint32_t C, +                                      CharSourceRange Range, bool IsFirst) { +  // Check C99 compatibility. +  if (!Diags.isIgnored(diag::warn_c99_compat_unicode_id, Range.getBegin())) { +    enum { +      CannotAppearInIdentifier = 0, +      CannotStartIdentifier +    }; + +    static const llvm::sys::UnicodeCharSet C99AllowedIDChars( +        C99AllowedIDCharRanges); +    static const llvm::sys::UnicodeCharSet C99DisallowedInitialIDChars( +        C99DisallowedInitialIDCharRanges); +    if (!C99AllowedIDChars.contains(C)) { +      Diags.Report(Range.getBegin(), diag::warn_c99_compat_unicode_id) +        << Range +        << CannotAppearInIdentifier; +    } else if (IsFirst && C99DisallowedInitialIDChars.contains(C)) { +      Diags.Report(Range.getBegin(), diag::warn_c99_compat_unicode_id) +        << Range +        << CannotStartIdentifier; +    } +  } + +  // Check C++98 compatibility. +  if (!Diags.isIgnored(diag::warn_cxx98_compat_unicode_id, Range.getBegin())) { +    static const llvm::sys::UnicodeCharSet CXX03AllowedIDChars( +        CXX03AllowedIDCharRanges); +    if (!CXX03AllowedIDChars.contains(C)) { +      Diags.Report(Range.getBegin(), diag::warn_cxx98_compat_unicode_id) +        << Range; +    } +  } +} + +/// After encountering UTF-8 character C and interpreting it as an identifier +/// character, check whether it's a homoglyph for a common non-identifier +/// source character that is unlikely to be an intentional identifier +/// character and warn if so. +static void maybeDiagnoseUTF8Homoglyph(DiagnosticsEngine &Diags, uint32_t C, +                                       CharSourceRange Range) { +  // FIXME: Handle Unicode quotation marks (smart quotes, fullwidth quotes). +  struct HomoglyphPair { +    uint32_t Character; +    char LooksLike; +    bool operator<(HomoglyphPair R) const { return Character < R.Character; } +  }; +  static constexpr HomoglyphPair SortedHomoglyphs[] = { +    {U'\u01c3', '!'}, // LATIN LETTER RETROFLEX CLICK +    {U'\u037e', ';'}, // GREEK QUESTION MARK +    {U'\u2212', '-'}, // MINUS SIGN +    {U'\u2215', '/'}, // DIVISION SLASH +    {U'\u2216', '\\'}, // SET MINUS +    {U'\u2217', '*'}, // ASTERISK OPERATOR +    {U'\u2223', '|'}, // DIVIDES +    {U'\u2227', '^'}, // LOGICAL AND +    {U'\u2236', ':'}, // RATIO +    {U'\u223c', '~'}, // TILDE OPERATOR +    {U'\ua789', ':'}, // MODIFIER LETTER COLON +    {U'\uff01', '!'}, // FULLWIDTH EXCLAMATION MARK +    {U'\uff03', '#'}, // FULLWIDTH NUMBER SIGN +    {U'\uff04', '$'}, // FULLWIDTH DOLLAR SIGN +    {U'\uff05', '%'}, // FULLWIDTH PERCENT SIGN +    {U'\uff06', '&'}, // FULLWIDTH AMPERSAND +    {U'\uff08', '('}, // FULLWIDTH LEFT PARENTHESIS +    {U'\uff09', ')'}, // FULLWIDTH RIGHT PARENTHESIS +    {U'\uff0a', '*'}, // FULLWIDTH ASTERISK +    {U'\uff0b', '+'}, // FULLWIDTH ASTERISK +    {U'\uff0c', ','}, // FULLWIDTH COMMA +    {U'\uff0d', '-'}, // FULLWIDTH HYPHEN-MINUS +    {U'\uff0e', '.'}, // FULLWIDTH FULL STOP +    {U'\uff0f', '/'}, // FULLWIDTH SOLIDUS +    {U'\uff1a', ':'}, // FULLWIDTH COLON +    {U'\uff1b', ';'}, // FULLWIDTH SEMICOLON +    {U'\uff1c', '<'}, // FULLWIDTH LESS-THAN SIGN +    {U'\uff1d', '='}, // FULLWIDTH EQUALS SIGN +    {U'\uff1e', '>'}, // FULLWIDTH GREATER-THAN SIGN +    {U'\uff1f', '?'}, // FULLWIDTH QUESTION MARK +    {U'\uff20', '@'}, // FULLWIDTH COMMERCIAL AT +    {U'\uff3b', '['}, // FULLWIDTH LEFT SQUARE BRACKET +    {U'\uff3c', '\\'}, // FULLWIDTH REVERSE SOLIDUS +    {U'\uff3d', ']'}, // FULLWIDTH RIGHT SQUARE BRACKET +    {U'\uff3e', '^'}, // FULLWIDTH CIRCUMFLEX ACCENT +    {U'\uff5b', '{'}, // FULLWIDTH LEFT CURLY BRACKET +    {U'\uff5c', '|'}, // FULLWIDTH VERTICAL LINE +    {U'\uff5d', '}'}, // FULLWIDTH RIGHT CURLY BRACKET +    {U'\uff5e', '~'}, // FULLWIDTH TILDE +    {0, 0} +  }; +  auto Homoglyph = +      std::lower_bound(std::begin(SortedHomoglyphs), +                       std::end(SortedHomoglyphs) - 1, HomoglyphPair{C, '\0'}); +  if (Homoglyph->Character == C) { +    llvm::SmallString<5> CharBuf; +    { +      llvm::raw_svector_ostream CharOS(CharBuf); +      llvm::write_hex(CharOS, C, llvm::HexPrintStyle::Upper, 4); +    } +    const char LooksLikeStr[] = {Homoglyph->LooksLike, 0}; +    Diags.Report(Range.getBegin(), diag::warn_utf8_symbol_homoglyph) +        << Range << CharBuf << LooksLikeStr; +  } +} + +bool Lexer::tryConsumeIdentifierUCN(const char *&CurPtr, unsigned Size, +                                    Token &Result) { +  const char *UCNPtr = CurPtr + Size; +  uint32_t CodePoint = tryReadUCN(UCNPtr, CurPtr, /*Token=*/nullptr); +  if (CodePoint == 0 || !isAllowedIDChar(CodePoint, LangOpts)) +    return false; + +  if (!isLexingRawMode()) +    maybeDiagnoseIDCharCompat(PP->getDiagnostics(), CodePoint, +                              makeCharRange(*this, CurPtr, UCNPtr), +                              /*IsFirst=*/false); + +  Result.setFlag(Token::HasUCN); +  if ((UCNPtr - CurPtr ==  6 && CurPtr[1] == 'u') || +      (UCNPtr - CurPtr == 10 && CurPtr[1] == 'U')) +    CurPtr = UCNPtr; +  else +    while (CurPtr != UCNPtr) +      (void)getAndAdvanceChar(CurPtr, Result); +  return true; +} + +bool Lexer::tryConsumeIdentifierUTF8Char(const char *&CurPtr) { +  const char *UnicodePtr = CurPtr; +  llvm::UTF32 CodePoint; +  llvm::ConversionResult Result = +      llvm::convertUTF8Sequence((const llvm::UTF8 **)&UnicodePtr, +                                (const llvm::UTF8 *)BufferEnd, +                                &CodePoint, +                                llvm::strictConversion); +  if (Result != llvm::conversionOK || +      !isAllowedIDChar(static_cast<uint32_t>(CodePoint), LangOpts)) +    return false; + +  if (!isLexingRawMode()) { +    maybeDiagnoseIDCharCompat(PP->getDiagnostics(), CodePoint, +                              makeCharRange(*this, CurPtr, UnicodePtr), +                              /*IsFirst=*/false); +    maybeDiagnoseUTF8Homoglyph(PP->getDiagnostics(), CodePoint, +                               makeCharRange(*this, CurPtr, UnicodePtr)); +  } + +  CurPtr = UnicodePtr; +  return true; +} + +bool 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 $,\,? in identifier found.  '\' might be an escaped newline +  // or UCN, and ? might be a trigraph for '\', an escaped newline or UCN. +  // +  // TODO: Could merge these checks into an InfoTable flag to make the +  // comparison cheaper +  if (isASCII(C) && C != '\\' && C != '?' && +      (C != '$' || !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 true; + +    // Fill in Result.IdentifierInfo and update the token kind, +    // looking up the identifier in the identifier table. +    IdentifierInfo *II = PP->LookUpIdentifierInfo(Result); +    // Note that we have to call PP->LookUpIdentifierInfo() even for code +    // completion, it writes IdentifierInfo into Result, and callers rely on it. + +    // If the completion point is at the end of an identifier, we want to treat +    // the identifier as incomplete even if it resolves to a macro or a keyword. +    // This allows e.g. 'class^' to complete to 'classifier'. +    if (isCodeCompletionPoint(CurPtr)) { +      // Return the code-completion token. +      Result.setKind(tok::code_completion); +      // Skip the code-completion char and all immediate identifier characters. +      // This ensures we get consistent behavior when completing at any point in +      // an identifier (i.e. at the start, in the middle, at the end). Note that +      // only simple cases (i.e. [a-zA-Z0-9_]) are supported to keep the code +      // simpler. +      assert(*CurPtr == 0 && "Completion character must be 0"); +      ++CurPtr; +      // Note that code completion token is not added as a separate character +      // when the completion point is at the end of the buffer. Therefore, we need +      // to check if the buffer has ended. +      if (CurPtr < BufferEnd) { +        while (isIdentifierBody(*CurPtr)) +          ++CurPtr; +      } +      BufferPtr = CurPtr; +      return true; +    } + +    // 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()) +      return PP->HandleIdentifier(Result); + +    return true; +  } + +  // Otherwise, $,\,? in identifier found.  Enter slower path. + +  C = getCharAndSize(CurPtr, Size); +  while (true) { +    if (C == '$') { +      // 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 (C == '\\' && tryConsumeIdentifierUCN(CurPtr, Size, Result)) { +      C = getCharAndSize(CurPtr, Size); +      continue; +    } else if (!isASCII(C) && tryConsumeIdentifierUTF8Char(CurPtr)) { +      C = getCharAndSize(CurPtr, Size); +      continue; +    } else if (!isIdentifierBody(C)) { +      goto FinishIdentifier; +    } + +    // Otherwise, this character is good, consume it. +    CurPtr = ConsumeChar(CurPtr, Size, Result); + +    C = getCharAndSize(CurPtr, Size); +    while (isIdentifierBody(C)) { +      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). +bool Lexer::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. +bool Lexer::LexNumericConstant(Token &Result, const char *CurPtr) { +  unsigned Size; +  char C = getCharAndSize(CurPtr, Size); +  char PrevCh = 0; +  while (isPreprocessingNumberBody(C)) { +    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')) { +    // Outside C99 and C++17, we accept hexadecimal floating point numbers as a +    // not-quite-conforming extension. Only do so if this looks like it's +    // actually meant to be a hexfloat, and not if it has a ud-suffix. +    bool IsHexFloat = true; +    if (!LangOpts.C99) { +      if (!isHexaLiteral(BufferPtr, LangOpts)) +        IsHexFloat = false; +      else if (!getLangOpts().CPlusPlus17 && +               std::find(BufferPtr, CurPtr, '_') != CurPtr) +        IsHexFloat = false; +    } +    if (IsHexFloat) +      return LexNumericConstant(Result, ConsumeChar(CurPtr, Size, Result)); +  } + +  // If we have a digit separator, continue. +  if (C == '\'' && getLangOpts().CPlusPlus14) { +    unsigned NextSize; +    char Next = getCharAndSizeNoWarn(CurPtr + Size, NextSize, getLangOpts()); +    if (isIdentifierBody(Next)) { +      if (!isLexingRawMode()) +        Diag(CurPtr, diag::warn_cxx11_compat_digit_separator); +      CurPtr = ConsumeChar(CurPtr, Size, Result); +      CurPtr = ConsumeChar(CurPtr, NextSize, Result); +      return LexNumericConstant(Result, CurPtr); +    } +  } + +  // If we have a UCN or UTF-8 character (perhaps in a ud-suffix), continue. +  if (C == '\\' && tryConsumeIdentifierUCN(CurPtr, Size, Result)) +    return LexNumericConstant(Result, CurPtr); +  if (!isASCII(C) && tryConsumeIdentifierUTF8Char(CurPtr)) +    return LexNumericConstant(Result, CurPtr); + +  // Update the location of token as well as BufferPtr. +  const char *TokStart = BufferPtr; +  FormTokenWithChars(Result, CurPtr, tok::numeric_constant); +  Result.setLiteralData(TokStart); +  return true; +} + +/// 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, +                               bool IsStringLiteral) { +  assert(getLangOpts().CPlusPlus); + +  // Maximally munch an identifier. +  unsigned Size; +  char C = getCharAndSize(CurPtr, Size); +  bool Consumed = false; + +  if (!isIdentifierHead(C)) { +    if (C == '\\' && tryConsumeIdentifierUCN(CurPtr, Size, Result)) +      Consumed = true; +    else if (!isASCII(C) && tryConsumeIdentifierUTF8Char(CurPtr)) +      Consumed = true; +    else +      return CurPtr; +  } + +  if (!getLangOpts().CPlusPlus11) { +    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. We assume a suffix beginning with a UCN or UTF-8 character is more +  // likely to be a ud-suffix than a macro, however, and accept that. +  if (!Consumed) { +    bool IsUDSuffix = false; +    if (C == '_') +      IsUDSuffix = true; +    else if (IsStringLiteral && getLangOpts().CPlusPlus14) { +      // In C++1y, we need to look ahead a few characters to see if this is a +      // valid suffix for a string literal or a numeric literal (this could be +      // the 'operator""if' defining a numeric literal operator). +      const unsigned MaxStandardSuffixLength = 3; +      char Buffer[MaxStandardSuffixLength] = { C }; +      unsigned Consumed = Size; +      unsigned Chars = 1; +      while (true) { +        unsigned NextSize; +        char Next = getCharAndSizeNoWarn(CurPtr + Consumed, NextSize, +                                         getLangOpts()); +        if (!isIdentifierBody(Next)) { +          // End of suffix. Check whether this is on the whitelist. +          const StringRef CompleteSuffix(Buffer, Chars); +          IsUDSuffix = StringLiteralParser::isValidUDSuffix(getLangOpts(), +                                                            CompleteSuffix); +          break; +        } + +        if (Chars == MaxStandardSuffixLength) +          // Too long: can't be a standard suffix. +          break; + +        Buffer[Chars++] = Next; +        Consumed += NextSize; +      } +    } + +    if (!IsUDSuffix) { +      if (!isLexingRawMode()) +        Diag(CurPtr, getLangOpts().MSVCCompat +                         ? diag::ext_ms_reserved_user_defined_literal +                         : diag::ext_reserved_user_defined_literal) +          << FixItHint::CreateInsertion(getSourceLocation(CurPtr), " "); +      return CurPtr; +    } + +    CurPtr = ConsumeChar(CurPtr, Size, Result); +  } + +  Result.setFlag(Token::HasUDSuffix); +  while (true) { +    C = getCharAndSize(CurPtr, Size); +    if (isIdentifierBody(C)) { CurPtr = ConsumeChar(CurPtr, Size, Result); } +    else if (C == '\\' && tryConsumeIdentifierUCN(CurPtr, Size, Result)) {} +    else if (!isASCII(C) && tryConsumeIdentifierUTF8Char(CurPtr)) {} +    else break; +  } + +  return CurPtr; +} + +/// LexStringLiteral - Lex the remainder of a string literal, after having lexed +/// either " or L" or u8" or u" or U". +bool Lexer::LexStringLiteral(Token &Result, const char *CurPtr, +                             tok::TokenKind Kind) { +  // Does this string contain the \0 character? +  const char *NulCharacter = nullptr; + +  if (!isLexingRawMode() && +      (Kind == tok::utf8_string_literal || +       Kind == tok::utf16_string_literal || +       Kind == tok::utf32_string_literal)) +    Diag(BufferPtr, getLangOpts().CPlusPlus +           ? diag::warn_cxx98_compat_unicode_literal +           : diag::warn_c99_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::ext_unterminated_char_or_string) << 1; +      FormTokenWithChars(Result, CurPtr-1, tok::unknown); +      return true; +    } + +    if (C == 0) { +      if (isCodeCompletionPoint(CurPtr-1)) { +        PP->CodeCompleteNaturalLanguage(); +        FormTokenWithChars(Result, CurPtr-1, tok::unknown); +        cutOffLexing(); +        return true; +      } + +      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, true); + +  // If a nul character existed in the string, warn about it. +  if (NulCharacter && !isLexingRawMode()) +    Diag(NulCharacter, diag::null_in_char_or_string) << 1; + +  // Update the location of the token as well as the BufferPtr instance var. +  const char *TokStart = BufferPtr; +  FormTokenWithChars(Result, CurPtr, Kind); +  Result.setLiteralData(TokStart); +  return true; +} + +/// LexRawStringLiteral - Lex the remainder of a raw string literal, after +/// having lexed R", LR", u8R", uR", or UR". +bool 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 (true) { +      char C = *CurPtr++; + +      if (C == '"') +        break; +      if (C == 0 && CurPtr-1 == BufferEnd) { +        --CurPtr; +        break; +      } +    } + +    FormTokenWithChars(Result, CurPtr, tok::unknown); +    return true; +  } + +  // Save prefix and move CurPtr past it +  const char *Prefix = CurPtr; +  CurPtr += PrefixLen + 1; // skip over prefix and '(' + +  while (true) { +    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 true; +    } +  } + +  // If we are in C++11, lex the optional ud-suffix. +  if (getLangOpts().CPlusPlus) +    CurPtr = LexUDSuffix(Result, CurPtr, true); + +  // Update the location of token as well as BufferPtr. +  const char *TokStart = BufferPtr; +  FormTokenWithChars(Result, CurPtr, Kind); +  Result.setLiteralData(TokStart); +  return true; +} + +/// LexAngledStringLiteral - Lex the remainder of an angled string literal, +/// after having lexed the '<' character.  This is used for #include filenames. +bool Lexer::LexAngledStringLiteral(Token &Result, const char *CurPtr) { +  // Does this string contain the \0 character? +  const char *NulCharacter = nullptr; +  const char *AfterLessPos = CurPtr; +  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. +                    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 true; +    } + +    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_char_or_string) << 1; + +  // Update the location of token as well as BufferPtr. +  const char *TokStart = BufferPtr; +  FormTokenWithChars(Result, CurPtr, tok::angle_string_literal); +  Result.setLiteralData(TokStart); +  return true; +} + +/// LexCharConstant - Lex the remainder of a character constant, after having +/// lexed either ' or L' or u8' or u' or U'. +bool Lexer::LexCharConstant(Token &Result, const char *CurPtr, +                            tok::TokenKind Kind) { +  // Does this character contain the \0 character? +  const char *NulCharacter = nullptr; + +  if (!isLexingRawMode()) { +    if (Kind == tok::utf16_char_constant || Kind == tok::utf32_char_constant) +      Diag(BufferPtr, getLangOpts().CPlusPlus +                          ? diag::warn_cxx98_compat_unicode_literal +                          : diag::warn_c99_compat_unicode_literal); +    else if (Kind == tok::utf8_char_constant) +      Diag(BufferPtr, diag::warn_cxx14_compat_u8_character_literal); +  } + +  char C = getAndAdvanceChar(CurPtr, Result); +  if (C == '\'') { +    if (!isLexingRawMode() && !LangOpts.AsmPreprocessor) +      Diag(BufferPtr, diag::ext_empty_character); +    FormTokenWithChars(Result, CurPtr, tok::unknown); +    return true; +  } + +  while (C != '\'') { +    // Skip escaped characters. +    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::ext_unterminated_char_or_string) << 0; +      FormTokenWithChars(Result, CurPtr-1, tok::unknown); +      return true; +    } + +    if (C == 0) { +      if (isCodeCompletionPoint(CurPtr-1)) { +        PP->CodeCompleteNaturalLanguage(); +        FormTokenWithChars(Result, CurPtr-1, tok::unknown); +        cutOffLexing(); +        return true; +      } + +      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, false); + +  // If a nul character existed in the character, warn about it. +  if (NulCharacter && !isLexingRawMode()) +    Diag(NulCharacter, diag::null_in_char_or_string) << 0; + +  // Update the location of token as well as BufferPtr. +  const char *TokStart = BufferPtr; +  FormTokenWithChars(Result, CurPtr, Kind); +  Result.setLiteralData(TokStart); +  return true; +} + +/// 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, +                           bool &TokAtPhysicalStartOfLine) { +  // Whitespace - Skip it, then return the token after the whitespace. +  bool SawNewline = isVerticalWhitespace(CurPtr[-1]); + +  unsigned char Char = *CurPtr; + +  // Skip consecutive spaces efficiently. +  while (true) { +    // Skip horizontal whitespace very aggressively. +    while (isHorizontalWhitespace(Char)) +      Char = *++CurPtr; + +    // Otherwise if we have something other than whitespace, we're done. +    if (!isVerticalWhitespace(Char)) +      break; + +    if (ParsingPreprocessorDirective) { +      // End of preprocessor directive line, let LexTokenInternal handle this. +      BufferPtr = CurPtr; +      return false; +    } + +    // OK, but handle newline. +    SawNewline = true; +    Char = *++CurPtr; +  } + +  // If the client wants us to return whitespace, return it now. +  if (isKeepWhitespaceMode()) { +    FormTokenWithChars(Result, CurPtr, tok::unknown); +    if (SawNewline) { +      IsAtStartOfLine = true; +      IsAtPhysicalStartOfLine = true; +    } +    // FIXME: The next token will not have LeadingSpace set. +    return true; +  } + +  // If this isn't immediately after a newline, there is leading space. +  char PrevChar = CurPtr[-1]; +  bool HasLeadingSpace = !isVerticalWhitespace(PrevChar); + +  Result.setFlagValue(Token::LeadingSpace, HasLeadingSpace); +  if (SawNewline) { +    Result.setFlag(Token::StartOfLine); +    TokAtPhysicalStartOfLine = true; +  } + +  BufferPtr = CurPtr; +  return false; +} + +/// We have just read the // characters from input.  Skip until we find the +/// newline character that terminates 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::SkipLineComment(Token &Result, const char *CurPtr, +                            bool &TokAtPhysicalStartOfLine) { +  // If Line comments aren't explicitly enabled for this language, emit an +  // extension warning. +  if (!LangOpts.LineComment && !isLexingRawMode()) { +    Diag(BufferPtr, diag::ext_line_comment); + +    // Mark them enabled so we only emit one warning for this translation +    // unit. +    LangOpts.LineComment = 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. +  // +  // This loop terminates with CurPtr pointing at the newline (or end of buffer) +  // character that ends the line comment. +  char C; +  while (true) { +    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; +      bool HasSpace = false; +      while (isHorizontalWhitespace(*EscapePtr)) { // Skip whitespace. +        --EscapePtr; +        HasSpace = true; +      } + +      if (*EscapePtr == '\\') +        // Escaped newline. +        CurPtr = EscapePtr; +      else if (EscapePtr[0] == '/' && EscapePtr[-1] == '?' && +               EscapePtr[-2] == '?' && LangOpts.Trigraphs) +        // Trigraph-escaped newline. +        CurPtr = EscapePtr-2; +      else +        break; // This is a newline, we're done. + +      // If there was space between the backslash and newline, warn about it. +      if (HasSpace && !isLexingRawMode()) +        Diag(EscapePtr, diag::backslash_newline_space); +    } + +    // 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 == BufferEnd + 1 || 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_line_comment); +          break; +        } +    } + +    if (C == '\r' || C == '\n' || CurPtr == BufferEnd + 1) { +      --CurPtr; +      break; +    } + +    if (C == '\0' && isCodeCompletionPoint(CurPtr-1)) { +      PP->CodeCompleteNaturalLanguage(); +      cutOffLexing(); +      return false; +    } +  } + +  // 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 SaveLineComment(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); +  TokAtPhysicalStartOfLine = true; +  // No leading whitespace seen so far. +  Result.clearFlag(Token::LeadingSpace); +  BufferPtr = CurPtr; +  return false; +} + +/// If in save-comment mode, package up this Line comment in an appropriate +/// way and return it. +bool Lexer::SaveLineComment(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 || LexingRawMode) +    return true; + +  // If this Line-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 line comment?"); +  Spelling[1] = '*';   // Change prefix to "/*". +  Spelling += "*/";    // add suffix. + +  Result.setKind(tok::comment); +  PP->CreateString(Spelling, 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 + +/// We have just read from input the / and * characters that started a comment. +/// Read until we find the * and / 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 terminating * and /. +/// +/// 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, +                             bool &TokAtPhysicalStartOfLine) { +  // 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 (true) { +    // 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(*(const __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<unsigned>(cmp) + 1; +          goto FoundSlash; +        } +        CurPtr += 16; +      } +#elif __ALTIVEC__ +      __vector unsigned char Slashes = { +        '/', '/', '/', '/',  '/', '/', '/', '/', +        '/', '/', '/', '/',  '/', '/', '/', '/' +      }; +      while (CurPtr+16 <= BufferEnd && +             !vec_any_eq(*(const 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)) { +    SkipWhitespace(Result, CurPtr+1, TokAtPhysicalStartOfLine); +    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. +void Lexer::ReadToEndOfLine(SmallVectorImpl<char> *Result) { +  assert(ParsingPreprocessorDirective && ParsingFilename == false && +         "Must be in a preprocessing directive!"); +  Token Tmp; + +  // CurPtr - Cache BufferPtr in an automatic variable. +  const char *CurPtr = BufferPtr; +  while (true) { +    char Char = getAndAdvanceChar(CurPtr, Tmp); +    switch (Char) { +    default: +      if (Result) +        Result->push_back(Char); +      break; +    case 0:  // Null. +      // Found end of file? +      if (CurPtr-1 != BufferEnd) { +        if (isCodeCompletionPoint(CurPtr-1)) { +          PP->CodeCompleteNaturalLanguage(); +          cutOffLexing(); +          return; +        } + +        // Nope, normal character, continue. +        if (Result) +          Result->push_back(Char); +        break; +      } +      // FALL THROUGH. +      LLVM_FALLTHROUGH; +    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; +    } +  } +} + +/// 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. +    if (PP) +      resetExtendedTokenMode(); +    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; +  } + +  if (PP->isRecordingPreamble() && PP->isInPrimaryFile()) { +    PP->setRecordedPreambleConditionalStack(ConditionalStack); +    ConditionalStack.clear(); +  } + +  // 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')) { +    DiagnosticsEngine &Diags = PP->getDiagnostics(); +    SourceLocation EndLoc = getSourceLocation(BufferEnd); +    unsigned DiagID; + +    if (LangOpts.CPlusPlus11) { +      // C++11 [lex.phases] 2.2 p2 +      // Prefer the C++98 pedantic compatibility warning over the generic, +      // non-extension, user-requested "missing newline at EOF" warning. +      if (!Diags.isIgnored(diag::warn_cxx98_compat_no_newline_eof, EndLoc)) { +        DiagID = diag::warn_cxx98_compat_no_newline_eof; +      } else { +        DiagID = diag::warn_no_newline_eof; +      } +    } else { +      DiagID = diag::ext_no_newline_eof; +    } + +    Diag(BufferEnd, DiagID) +      << FixItHint::CreateInsertion(EndLoc, "\n"); +  } + +  BufferPtr = CurPtr; + +  // Finally, let the preprocessor handle this. +  return PP->HandleEndOfFile(Result, isPragmaLexer()); +} + +/// 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; +  bool atStartOfLine = IsAtStartOfLine; +  bool atPhysicalStartOfLine = IsAtPhysicalStartOfLine; +  bool leadingSpace = HasLeadingSpace; + +  Token Tok; +  Lex(Tok); + +  // Restore state that may have changed. +  BufferPtr = TmpBufferPtr; +  ParsingPreprocessorDirective = inPPDirectiveMode; +  HasLeadingSpace = leadingSpace; +  IsAtStartOfLine = atStartOfLine; +  IsAtPhysicalStartOfLine = atPhysicalStartOfLine; + +  // Restore the lexer back to non-skipping mode. +  LexingRawMode = false; + +  if (Tok.is(tok::eof)) +    return 2; +  return Tok.is(tok::l_paren); +} + +/// 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; +  auto RestOfBuffer = StringRef(CurPtr, BufferEnd - CurPtr).substr(TermLen); +  size_t Pos = RestOfBuffer.find(Terminator); +  while (Pos != StringRef::npos) { +    // Must occur at start of line. +    if (Pos == 0 || +        (RestOfBuffer[Pos - 1] != '\r' && RestOfBuffer[Pos - 1] != '\n')) { +      RestOfBuffer = RestOfBuffer.substr(Pos+TermLen); +      Pos = RestOfBuffer.find(Terminator); +      continue; +    } +    return RestOfBuffer.data()+Pos; +  } +  return nullptr; +} + +/// 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 (!StringRef(CurPtr, BufferEnd - CurPtr).startswith("<<<<<<<") && +      !StringRef(CurPtr, BufferEnd - CurPtr).startswith(">>>> ")) +    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; +} + +static const char *findPlaceholderEnd(const char *CurPtr, +                                      const char *BufferEnd) { +  if (CurPtr == BufferEnd) +    return nullptr; +  BufferEnd -= 1; // Scan until the second last character. +  for (; CurPtr != BufferEnd; ++CurPtr) { +    if (CurPtr[0] == '#' && CurPtr[1] == '>') +      return CurPtr + 2; +  } +  return nullptr; +} + +bool Lexer::lexEditorPlaceholder(Token &Result, const char *CurPtr) { +  assert(CurPtr[-1] == '<' && CurPtr[0] == '#' && "Not a placeholder!"); +  if (!PP || !PP->getPreprocessorOpts().LexEditorPlaceholders || LexingRawMode) +    return false; +  const char *End = findPlaceholderEnd(CurPtr + 1, BufferEnd); +  if (!End) +    return false; +  const char *Start = CurPtr - 1; +  if (!LangOpts.AllowEditorPlaceholders) +    Diag(Start, diag::err_placeholder_in_source); +  Result.startToken(); +  FormTokenWithChars(Result, End, tok::raw_identifier); +  Result.setRawIdentifierData(Start); +  PP->LookUpIdentifierInfo(Result); +  Result.setFlag(Token::IsEditorPlaceholder); +  BufferPtr = End; +  return true; +} + +bool Lexer::isCodeCompletionPoint(const char *CurPtr) const { +  if (PP && PP->isCodeCompletionEnabled()) { +    SourceLocation Loc = FileLoc.getLocWithOffset(CurPtr-BufferStart); +    return Loc == PP->getCodeCompletionLoc(); +  } + +  return false; +} + +uint32_t Lexer::tryReadUCN(const char *&StartPtr, const char *SlashLoc, +                           Token *Result) { +  unsigned CharSize; +  char Kind = getCharAndSize(StartPtr, CharSize); + +  unsigned NumHexDigits; +  if (Kind == 'u') +    NumHexDigits = 4; +  else if (Kind == 'U') +    NumHexDigits = 8; +  else +    return 0; + +  if (!LangOpts.CPlusPlus && !LangOpts.C99) { +    if (Result && !isLexingRawMode()) +      Diag(SlashLoc, diag::warn_ucn_not_valid_in_c89); +    return 0; +  } + +  const char *CurPtr = StartPtr + CharSize; +  const char *KindLoc = &CurPtr[-1]; + +  uint32_t CodePoint = 0; +  for (unsigned i = 0; i < NumHexDigits; ++i) { +    char C = getCharAndSize(CurPtr, CharSize); + +    unsigned Value = llvm::hexDigitValue(C); +    if (Value == -1U) { +      if (Result && !isLexingRawMode()) { +        if (i == 0) { +          Diag(BufferPtr, diag::warn_ucn_escape_no_digits) +            << StringRef(KindLoc, 1); +        } else { +          Diag(BufferPtr, diag::warn_ucn_escape_incomplete); + +          // If the user wrote \U1234, suggest a fixit to \u. +          if (i == 4 && NumHexDigits == 8) { +            CharSourceRange URange = makeCharRange(*this, KindLoc, KindLoc + 1); +            Diag(KindLoc, diag::note_ucn_four_not_eight) +              << FixItHint::CreateReplacement(URange, "u"); +          } +        } +      } + +      return 0; +    } + +    CodePoint <<= 4; +    CodePoint += Value; + +    CurPtr += CharSize; +  } + +  if (Result) { +    Result->setFlag(Token::HasUCN); +    if (CurPtr - StartPtr == (ptrdiff_t)NumHexDigits + 2) +      StartPtr = CurPtr; +    else +      while (StartPtr != CurPtr) +        (void)getAndAdvanceChar(StartPtr, *Result); +  } else { +    StartPtr = CurPtr; +  } + +  // Don't apply C family restrictions to UCNs in assembly mode +  if (LangOpts.AsmPreprocessor) +    return CodePoint; + +  // C99 6.4.3p2: A universal character name shall not specify a character whose +  //   short identifier is less than 00A0 other than 0024 ($), 0040 (@), or +  //   0060 (`), nor one in the range D800 through DFFF inclusive.) +  // C++11 [lex.charset]p2: If the hexadecimal value for a +  //   universal-character-name corresponds to a surrogate code point (in the +  //   range 0xD800-0xDFFF, inclusive), the program is ill-formed. Additionally, +  //   if the hexadecimal value for a universal-character-name outside the +  //   c-char-sequence, s-char-sequence, or r-char-sequence of a character or +  //   string literal corresponds to a control character (in either of the +  //   ranges 0x00-0x1F or 0x7F-0x9F, both inclusive) or to a character in the +  //   basic source character set, the program is ill-formed. +  if (CodePoint < 0xA0) { +    if (CodePoint == 0x24 || CodePoint == 0x40 || CodePoint == 0x60) +      return CodePoint; + +    // We don't use isLexingRawMode() here because we need to warn about bad +    // UCNs even when skipping preprocessing tokens in a #if block. +    if (Result && PP) { +      if (CodePoint < 0x20 || CodePoint >= 0x7F) +        Diag(BufferPtr, diag::err_ucn_control_character); +      else { +        char C = static_cast<char>(CodePoint); +        Diag(BufferPtr, diag::err_ucn_escape_basic_scs) << StringRef(&C, 1); +      } +    } + +    return 0; +  } else if (CodePoint >= 0xD800 && CodePoint <= 0xDFFF) { +    // C++03 allows UCNs representing surrogate characters. C99 and C++11 don't. +    // We don't use isLexingRawMode() here because we need to diagnose bad +    // UCNs even when skipping preprocessing tokens in a #if block. +    if (Result && PP) { +      if (LangOpts.CPlusPlus && !LangOpts.CPlusPlus11) +        Diag(BufferPtr, diag::warn_ucn_escape_surrogate); +      else +        Diag(BufferPtr, diag::err_ucn_escape_invalid); +    } +    return 0; +  } + +  return CodePoint; +} + +bool Lexer::CheckUnicodeWhitespace(Token &Result, uint32_t C, +                                   const char *CurPtr) { +  static const llvm::sys::UnicodeCharSet UnicodeWhitespaceChars( +      UnicodeWhitespaceCharRanges); +  if (!isLexingRawMode() && !PP->isPreprocessedOutput() && +      UnicodeWhitespaceChars.contains(C)) { +    Diag(BufferPtr, diag::ext_unicode_whitespace) +      << makeCharRange(*this, BufferPtr, CurPtr); + +    Result.setFlag(Token::LeadingSpace); +    return true; +  } +  return false; +} + +bool Lexer::LexUnicode(Token &Result, uint32_t C, const char *CurPtr) { +  if (isAllowedIDChar(C, LangOpts) && isAllowedInitiallyIDChar(C, LangOpts)) { +    if (!isLexingRawMode() && !ParsingPreprocessorDirective && +        !PP->isPreprocessedOutput()) { +      maybeDiagnoseIDCharCompat(PP->getDiagnostics(), C, +                                makeCharRange(*this, BufferPtr, CurPtr), +                                /*IsFirst=*/true); +    } + +    MIOpt.ReadToken(); +    return LexIdentifier(Result, CurPtr); +  } + +  if (!isLexingRawMode() && !ParsingPreprocessorDirective && +      !PP->isPreprocessedOutput() && +      !isASCII(*BufferPtr) && !isAllowedIDChar(C, LangOpts)) { +    // Non-ASCII characters tend to creep into source code unintentionally. +    // Instead of letting the parser complain about the unknown token, +    // just drop the character. +    // Note that we can /only/ do this when the non-ASCII character is actually +    // spelled as Unicode, not written as a UCN. The standard requires that +    // we not throw away any possible preprocessor tokens, but there's a +    // loophole in the mapping of Unicode characters to basic character set +    // characters that allows us to map these particular characters to, say, +    // whitespace. +    Diag(BufferPtr, diag::err_non_ascii) +      << FixItHint::CreateRemoval(makeCharRange(*this, BufferPtr, CurPtr)); + +    BufferPtr = CurPtr; +    return false; +  } + +  // Otherwise, we have an explicit UCN or a character that's unlikely to show +  // up by accident. +  MIOpt.ReadToken(); +  FormTokenWithChars(Result, CurPtr, tok::unknown); +  return true; +} + +void Lexer::PropagateLineStartLeadingSpaceInfo(Token &Result) { +  IsAtStartOfLine = Result.isAtStartOfLine(); +  HasLeadingSpace = Result.hasLeadingSpace(); +  HasLeadingEmptyMacro = Result.hasLeadingEmptyMacro(); +  // Note that this doesn't affect IsAtPhysicalStartOfLine. +} + +bool Lexer::Lex(Token &Result) { +  // Start a new token. +  Result.startToken(); + +  // Set up misc whitespace flags for LexTokenInternal. +  if (IsAtStartOfLine) { +    Result.setFlag(Token::StartOfLine); +    IsAtStartOfLine = false; +  } + +  if (HasLeadingSpace) { +    Result.setFlag(Token::LeadingSpace); +    HasLeadingSpace = false; +  } + +  if (HasLeadingEmptyMacro) { +    Result.setFlag(Token::LeadingEmptyMacro); +    HasLeadingEmptyMacro = false; +  } + +  bool atPhysicalStartOfLine = IsAtPhysicalStartOfLine; +  IsAtPhysicalStartOfLine = false; +  bool isRawLex = isLexingRawMode(); +  (void) isRawLex; +  bool returnedToken = LexTokenInternal(Result, atPhysicalStartOfLine); +  // (After the LexTokenInternal call, the lexer might be destroyed.) +  assert((returnedToken || !isRawLex) && "Raw lex must succeed"); +  return returnedToken; +} + +/// 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. +bool Lexer::LexTokenInternal(Token &Result, bool TokAtPhysicalStartOfLine) { +LexNextToken: +  // New token, can't need cleaning yet. +  Result.clearFlag(Token::NeedsCleaning); +  Result.setIdentifierInfo(nullptr); + +  // 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); +      // FIXME: The next token will not have LeadingSpace set. +      return true; +    } + +    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) +      return LexEndOfFile(Result, CurPtr-1); + +    // 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 true; +    } + +    if (!isLexingRawMode()) +      Diag(CurPtr-1, diag::null_in_file); +    Result.setFlag(Token::LeadingSpace); +    if (SkipWhitespace(Result, CurPtr, TokAtPhysicalStartOfLine)) +      return true; // KeepWhitespaceMode + +    // We know the lexer hasn't changed, so just try again with this lexer. +    // (We manually eliminate the tail call to avoid recursion.) +    goto LexNextToken; + +  case 26:  // DOS & CP/M EOF: "^Z". +    // If we're in Microsoft extensions mode, treat this as end of file. +    if (LangOpts.MicrosoftExt) { +      if (!isLexingRawMode()) +        Diag(CurPtr-1, diag::ext_ctrl_z_eof_microsoft); +      return LexEndOfFile(Result, CurPtr-1); +    } + +    // If Microsoft extensions are disabled, this is just random garbage. +    Kind = tok::unknown; +    break; + +  case '\r': +    if (CurPtr[0] == '\n') +      Char = getAndAdvanceChar(CurPtr, Result); +    LLVM_FALLTHROUGH; +  case '\n': +    // 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. +      if (PP) +        resetExtendedTokenMode(); + +      // Since we consumed a newline, we are back at the start of a line. +      IsAtStartOfLine = true; +      IsAtPhysicalStartOfLine = true; + +      Kind = tok::eod; +      break; +    } + +    // No leading whitespace seen so far. +    Result.clearFlag(Token::LeadingSpace); + +    if (SkipWhitespace(Result, CurPtr, TokAtPhysicalStartOfLine)) +      return true; // KeepWhitespaceMode + +    // We only saw whitespace, so just try again with this lexer. +    // (We manually eliminate the tail call to avoid recursion.) +    goto LexNextToken; +  case ' ': +  case '\t': +  case '\f': +  case '\v': +  SkipHorizontalWhitespace: +    Result.setFlag(Token::LeadingSpace); +    if (SkipWhitespace(Result, CurPtr, TokAtPhysicalStartOfLine)) +      return true; // 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.LineComment && +        (LangOpts.CPlusPlus || !LangOpts.TraditionalCPP)) { +      if (SkipLineComment(Result, CurPtr+2, TokAtPhysicalStartOfLine)) +        return true; // There is a token to return. +      goto SkipIgnoredUnits; +    } else if (CurPtr[0] == '/' && CurPtr[1] == '*' && !inKeepCommentMode()) { +      if (SkipBlockComment(Result, CurPtr+2, TokAtPhysicalStartOfLine)) +        return true; // There is a token to return. +      goto SkipIgnoredUnits; +    } else if (isHorizontalWhitespace(*CurPtr)) { +      goto SkipHorizontalWhitespace; +    } +    // We only saw whitespace, so just try again with this lexer. +    // (We manually eliminate the tail call to avoid recursion.) +    goto LexNextToken; + +  // 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 C11/C++11 UTF-8 or UTF-16 string literal +    // Notify MIOpt that we read a non-whitespace/non-comment token. +    MIOpt.ReadToken(); + +    if (LangOpts.CPlusPlus11 || LangOpts.C11) { +      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' && LangOpts.CPlusPlus11 && +          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 == '\'' && LangOpts.CPlusPlus17) +          return LexCharConstant( +              Result, ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result), +                                  SizeTmp2, Result), +              tok::utf8_char_constant); + +        if (Char2 == 'R' && LangOpts.CPlusPlus11) { +          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 C11/C++11 UTF-32 string literal +    // Notify MIOpt that we read a non-whitespace/non-comment token. +    MIOpt.ReadToken(); + +    if (LangOpts.CPlusPlus11 || LangOpts.C11) { +      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' && LangOpts.CPlusPlus11 && +          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.CPlusPlus11) { +      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.CPlusPlus11 && 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. +    LLVM_FALLTHROUGH; + +  // 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 == '/') {         // Line comment. +      // Even if Line 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 languages with Line 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 if we are just preprocessing. +      bool TreatAsComment = LangOpts.LineComment && +                            (LangOpts.CPlusPlus || !LangOpts.TraditionalCPP); +      if (!TreatAsComment) +        if (!(PP && PP->isPreprocessedOutput())) +          TreatAsComment = getCharAndSize(CurPtr+SizeTmp, SizeTmp2) != '*'; + +      if (TreatAsComment) { +        if (SkipLineComment(Result, ConsumeChar(CurPtr, SizeTmp, Result), +                            TokAtPhysicalStartOfLine)) +          return true; // 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), +                           TokAtPhysicalStartOfLine)) +        return true; // There is a token to return. + +      // We only saw whitespace, so just try again with this lexer. +      // (We manually eliminate the tail call to avoid recursion.) +      goto LexNextToken; +    } + +    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. +        // TODO: -fpreprocessed mode?? +        if (TokAtPhysicalStartOfLine && !LexingRawMode && !Is_PragmaLexer) +          goto HandleDirective; + +        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 == '=') { +      char After = getCharAndSize(CurPtr+SizeTmp, SizeTmp2); +      if (After == '>') { +        if (getLangOpts().CPlusPlus2a) { +          if (!isLexingRawMode()) +            Diag(BufferPtr, diag::warn_cxx17_compat_spaceship); +          CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result), +                               SizeTmp2, Result); +          Kind = tok::spaceship; +          break; +        } +        // Suggest adding a space between the '<=' and the '>' to avoid a +        // change in semantics if this turns up in C++ <=17 mode. +        if (getLangOpts().CPlusPlus && !isLexingRawMode()) { +          Diag(BufferPtr, diag::warn_cxx2a_compat_spaceship) +            << FixItHint::CreateInsertion( +                   getSourceLocation(CurPtr + SizeTmp, SizeTmp2), " "); +        } +      } +      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); +      Kind = tok::lessequal; +    } else if (LangOpts.Digraphs && Char == ':') {     // '<:' -> '[' +      if (LangOpts.CPlusPlus11 && +          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 if (Char == '#' && /*Not a trigraph*/ SizeTmp == 1 && +               lexEditorPlaceholder(Result, CurPtr)) { +      return true; +    } 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 if (LangOpts.OpenCL && Char == '^') { +      CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); +      Kind = tok::caretcaret; +    } 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 || +                LangOpts.DoubleSquareBracketAttributes) && +               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. +      // TODO: -fpreprocessed mode?? +      if (TokAtPhysicalStartOfLine && !LexingRawMode && !Is_PragmaLexer) +        goto HandleDirective; + +      Kind = tok::hash; +    } +    break; + +  case '@': +    // Objective C support. +    if (CurPtr[-1] == '@' && LangOpts.ObjC1) +      Kind = tok::at; +    else +      Kind = tok::unknown; +    break; + +  // UCNs (C99 6.4.3, C++11 [lex.charset]p2) +  case '\\': +    if (!LangOpts.AsmPreprocessor) { +      if (uint32_t CodePoint = tryReadUCN(CurPtr, BufferPtr, &Result)) { +        if (CheckUnicodeWhitespace(Result, CodePoint, CurPtr)) { +          if (SkipWhitespace(Result, CurPtr, TokAtPhysicalStartOfLine)) +            return true; // KeepWhitespaceMode + +          // We only saw whitespace, so just try again with this lexer. +          // (We manually eliminate the tail call to avoid recursion.) +          goto LexNextToken; +        } + +        return LexUnicode(Result, CodePoint, CurPtr); +      } +    } + +    Kind = tok::unknown; +    break; + +  default: { +    if (isASCII(Char)) { +      Kind = tok::unknown; +      break; +    } + +    llvm::UTF32 CodePoint; + +    // We can't just reset CurPtr to BufferPtr because BufferPtr may point to +    // an escaped newline. +    --CurPtr; +    const char *UTF8StartPtr = CurPtr; +    llvm::ConversionResult Status = +        llvm::convertUTF8Sequence((const llvm::UTF8 **)&CurPtr, +                                  (const llvm::UTF8 *)BufferEnd, +                                  &CodePoint, +                                  llvm::strictConversion); +    if (Status == llvm::conversionOK) { +      if (CheckUnicodeWhitespace(Result, CodePoint, CurPtr)) { +        if (SkipWhitespace(Result, CurPtr, TokAtPhysicalStartOfLine)) +          return true; // KeepWhitespaceMode + +        // We only saw whitespace, so just try again with this lexer. +        // (We manually eliminate the tail call to avoid recursion.) +        goto LexNextToken; +      } +      if (!isLexingRawMode()) +        maybeDiagnoseUTF8Homoglyph(PP->getDiagnostics(), CodePoint, +                                   makeCharRange(*this, UTF8StartPtr, CurPtr)); +      return LexUnicode(Result, CodePoint, CurPtr); +    } + +    if (isLexingRawMode() || ParsingPreprocessorDirective || +        PP->isPreprocessedOutput()) { +      ++CurPtr; +      Kind = tok::unknown; +      break; +    } + +    // Non-ASCII characters tend to creep into source code unintentionally. +    // Instead of letting the parser complain about the unknown token, +    // just diagnose the invalid UTF-8, then drop the character. +    Diag(CurPtr, diag::err_invalid_utf8); + +    BufferPtr = CurPtr+1; +    // We're pretending the character didn't exist, so just try again with +    // this lexer. +    // (We manually eliminate the tail call to avoid recursion.) +    goto LexNextToken; +  } +  } + +  // 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); +  return true; + +HandleDirective: +  // We parsed a # character and it's the start of a preprocessing directive. + +  FormTokenWithChars(Result, CurPtr, tok::hash); +  PP->HandleDirective(Result); + +  if (PP->hadModuleLoaderFatalFailure()) { +    // With a fatal failure in the module loader, we abort parsing. +    assert(Result.is(tok::eof) && "Preprocessor did not set tok:eof"); +    return true; +  } + +  // We parsed the directive; lex a token with the new state. +  return false; +}  | 
