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Diffstat (limited to 'lib/Lex/Lexer.cpp')
| -rw-r--r-- | lib/Lex/Lexer.cpp | 1809 |
1 files changed, 1809 insertions, 0 deletions
diff --git a/lib/Lex/Lexer.cpp b/lib/Lex/Lexer.cpp new file mode 100644 index 0000000..c2ffd6d --- /dev/null +++ b/lib/Lex/Lexer.cpp @@ -0,0 +1,1809 @@ +//===--- Lexer.cpp - C Language Family Lexer ------------------------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file implements the Lexer and Token interfaces. +// +//===----------------------------------------------------------------------===// +// +// TODO: GCC Diagnostics emitted by the lexer: +// PEDWARN: (form feed|vertical tab) in preprocessing directive +// +// Universal characters, unicode, char mapping: +// WARNING: `%.*s' is not in NFKC +// WARNING: `%.*s' is not in NFC +// +// Other: +// TODO: Options to support: +// -fexec-charset,-fwide-exec-charset +// +//===----------------------------------------------------------------------===// + +#include "clang/Lex/Lexer.h" +#include "clang/Lex/Preprocessor.h" +#include "clang/Lex/LexDiagnostic.h" +#include "clang/Basic/SourceManager.h" +#include "llvm/Support/Compiler.h" +#include "llvm/Support/MemoryBuffer.h" +#include <cctype> +using namespace clang; + +static void InitCharacterInfo(); + +//===----------------------------------------------------------------------===// +// Token Class Implementation +//===----------------------------------------------------------------------===// + +/// isObjCAtKeyword - Return true if we have an ObjC keyword identifier. +bool Token::isObjCAtKeyword(tok::ObjCKeywordKind objcKey) const { + if (IdentifierInfo *II = getIdentifierInfo()) + return II->getObjCKeywordID() == objcKey; + return false; +} + +/// getObjCKeywordID - Return the ObjC keyword kind. +tok::ObjCKeywordKind Token::getObjCKeywordID() const { + IdentifierInfo *specId = getIdentifierInfo(); + return specId ? specId->getObjCKeywordID() : tok::objc_not_keyword; +} + + +//===----------------------------------------------------------------------===// +// Lexer Class Implementation +//===----------------------------------------------------------------------===// + +void Lexer::InitLexer(const char *BufStart, const char *BufPtr, + const char *BufEnd) { + InitCharacterInfo(); + + BufferStart = BufStart; + BufferPtr = BufPtr; + BufferEnd = BufEnd; + + assert(BufEnd[0] == 0 && + "We assume that the input buffer has a null character at the end" + " to simplify lexing!"); + + Is_PragmaLexer = false; + + // Start of the file is a start of line. + IsAtStartOfLine = true; + + // We are not after parsing a #. + ParsingPreprocessorDirective = false; + + // We are not after parsing #include. + ParsingFilename = false; + + // We are not in raw mode. Raw mode disables diagnostics and interpretation + // of tokens (e.g. identifiers, thus disabling macro expansion). It is used + // to quickly lex the tokens of the buffer, e.g. when handling a "#if 0" block + // or otherwise skipping over tokens. + LexingRawMode = false; + + // Default to not keeping comments. + ExtendedTokenMode = 0; +} + +/// Lexer constructor - Create a new lexer object for the specified buffer +/// with the specified preprocessor managing the lexing process. This lexer +/// assumes that the associated file buffer and Preprocessor objects will +/// outlive it, so it doesn't take ownership of either of them. +Lexer::Lexer(FileID FID, Preprocessor &PP) + : PreprocessorLexer(&PP, FID), + FileLoc(PP.getSourceManager().getLocForStartOfFile(FID)), + Features(PP.getLangOptions()) { + + const llvm::MemoryBuffer *InputFile = PP.getSourceManager().getBuffer(FID); + + InitLexer(InputFile->getBufferStart(), InputFile->getBufferStart(), + InputFile->getBufferEnd()); + + // Default to keeping comments if the preprocessor wants them. + SetCommentRetentionState(PP.getCommentRetentionState()); +} + +/// Lexer constructor - Create a new raw lexer object. This object is only +/// suitable for calls to 'LexRawToken'. This lexer assumes that the text +/// range will outlive it, so it doesn't take ownership of it. +Lexer::Lexer(SourceLocation fileloc, const LangOptions &features, + const char *BufStart, const char *BufPtr, const char *BufEnd) + : FileLoc(fileloc), Features(features) { + + InitLexer(BufStart, BufPtr, BufEnd); + + // We *are* in raw mode. + LexingRawMode = true; +} + +/// Lexer constructor - Create a new raw lexer object. This object is only +/// suitable for calls to 'LexRawToken'. This lexer assumes that the text +/// range will outlive it, so it doesn't take ownership of it. +Lexer::Lexer(FileID FID, const SourceManager &SM, const LangOptions &features) + : FileLoc(SM.getLocForStartOfFile(FID)), Features(features) { + const llvm::MemoryBuffer *FromFile = SM.getBuffer(FID); + + InitLexer(FromFile->getBufferStart(), FromFile->getBufferStart(), + FromFile->getBufferEnd()); + + // We *are* in raw mode. + LexingRawMode = true; +} + +/// Create_PragmaLexer: Lexer constructor - Create a new lexer object for +/// _Pragma expansion. This has a variety of magic semantics that this method +/// sets up. It returns a new'd Lexer that must be delete'd when done. +/// +/// On entrance to this routine, TokStartLoc is a macro location which has a +/// spelling loc that indicates the bytes to be lexed for the token and an +/// instantiation location that indicates where all lexed tokens should be +/// "expanded from". +/// +/// FIXME: It would really be nice to make _Pragma just be a wrapper around a +/// normal lexer that remaps tokens as they fly by. This would require making +/// Preprocessor::Lex virtual. Given that, we could just dump in a magic lexer +/// interface that could handle this stuff. This would pull GetMappedTokenLoc +/// out of the critical path of the lexer! +/// +Lexer *Lexer::Create_PragmaLexer(SourceLocation SpellingLoc, + SourceLocation InstantiationLocStart, + SourceLocation InstantiationLocEnd, + 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); + Lexer *L = new Lexer(SpellingFID, 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.createInstantiationLoc(SM.getLocForStartOfFile(SpellingFID), + InstantiationLocStart, + InstantiationLocEnd, TokLen); + + // Ensure that the lexer thinks it is inside a directive, so that end \n will + // return an EOM token. + L->ParsingPreprocessorDirective = true; + + // This lexer really is for _Pragma. + L->Is_PragmaLexer = true; + return L; +} + + +/// Stringify - Convert the specified string into a C string, with surrounding +/// ""'s, and with escaped \ and " characters. +std::string Lexer::Stringify(const std::string &Str, bool Charify) { + std::string Result = Str; + char Quote = Charify ? '\'' : '"'; + for (unsigned i = 0, e = Result.size(); i != e; ++i) { + if (Result[i] == '\\' || Result[i] == Quote) { + Result.insert(Result.begin()+i, '\\'); + ++i; ++e; + } + } + return Result; +} + +/// Stringify - Convert the specified string into a C string by escaping '\' +/// and " characters. This does not add surrounding ""'s to the string. +void Lexer::Stringify(llvm::SmallVectorImpl<char> &Str) { + for (unsigned i = 0, e = Str.size(); i != e; ++i) { + if (Str[i] == '\\' || Str[i] == '"') { + Str.insert(Str.begin()+i, '\\'); + ++i; ++e; + } + } +} + + +/// MeasureTokenLength - Relex the token at the specified location and return +/// its length in bytes in the input file. If the token needs cleaning (e.g. +/// includes a trigraph or an escaped newline) then this count includes bytes +/// that are part of that. +unsigned Lexer::MeasureTokenLength(SourceLocation Loc, + const SourceManager &SM, + const LangOptions &LangOpts) { + // TODO: this could be special cased for common tokens like identifiers, ')', + // etc to make this faster, if it mattered. Just look at StrData[0] to handle + // all obviously single-char tokens. This could use + // Lexer::isObviouslySimpleCharacter for example to handle identifiers or + // something. + + // If this comes from a macro expansion, we really do want the macro name, not + // the token this macro expanded to. + Loc = SM.getInstantiationLoc(Loc); + std::pair<FileID, unsigned> LocInfo = SM.getDecomposedLoc(Loc); + std::pair<const char *,const char *> Buffer = SM.getBufferData(LocInfo.first); + const char *StrData = Buffer.first+LocInfo.second; + + // Create a lexer starting at the beginning of this token. + Lexer TheLexer(Loc, LangOpts, Buffer.first, StrData, Buffer.second); + Token TheTok; + TheLexer.LexFromRawLexer(TheTok); + return TheTok.getLength(); +} + +//===----------------------------------------------------------------------===// +// Character information. +//===----------------------------------------------------------------------===// + +static unsigned char CharInfo[256]; + +enum { + CHAR_HORZ_WS = 0x01, // ' ', '\t', '\f', '\v'. Note, no '\0' + CHAR_VERT_WS = 0x02, // '\r', '\n' + CHAR_LETTER = 0x04, // a-z,A-Z + CHAR_NUMBER = 0x08, // 0-9 + CHAR_UNDER = 0x10, // _ + CHAR_PERIOD = 0x20 // . +}; + +static void InitCharacterInfo() { + static bool isInited = false; + if (isInited) return; + isInited = true; + + // Intiialize the CharInfo table. + // TODO: statically initialize this. + CharInfo[(int)' '] = CharInfo[(int)'\t'] = + CharInfo[(int)'\f'] = CharInfo[(int)'\v'] = CHAR_HORZ_WS; + CharInfo[(int)'\n'] = CharInfo[(int)'\r'] = CHAR_VERT_WS; + + CharInfo[(int)'_'] = CHAR_UNDER; + CharInfo[(int)'.'] = CHAR_PERIOD; + for (unsigned i = 'a'; i <= 'z'; ++i) + CharInfo[i] = CharInfo[i+'A'-'a'] = CHAR_LETTER; + for (unsigned i = '0'; i <= '9'; ++i) + CharInfo[i] = CHAR_NUMBER; +} + +/// isIdentifierBody - Return true if this is the body character of an +/// identifier, which is [a-zA-Z0-9_]. +static inline bool isIdentifierBody(unsigned char c) { + return (CharInfo[c] & (CHAR_LETTER|CHAR_NUMBER|CHAR_UNDER)) ? true : false; +} + +/// isHorizontalWhitespace - Return true if this character is horizontal +/// whitespace: ' ', '\t', '\f', '\v'. Note that this returns false for '\0'. +static inline bool isHorizontalWhitespace(unsigned char c) { + return (CharInfo[c] & CHAR_HORZ_WS) ? true : false; +} + +/// isWhitespace - Return true if this character is horizontal or vertical +/// whitespace: ' ', '\t', '\f', '\v', '\n', '\r'. Note that this returns false +/// for '\0'. +static inline bool isWhitespace(unsigned char c) { + return (CharInfo[c] & (CHAR_HORZ_WS|CHAR_VERT_WS)) ? true : false; +} + +/// isNumberBody - Return true if this is the body character of an +/// preprocessing number, which is [a-zA-Z0-9_.]. +static inline bool isNumberBody(unsigned char c) { + return (CharInfo[c] & (CHAR_LETTER|CHAR_NUMBER|CHAR_UNDER|CHAR_PERIOD)) ? + true : false; +} + + +//===----------------------------------------------------------------------===// +// Diagnostics forwarding code. +//===----------------------------------------------------------------------===// + +/// GetMappedTokenLoc - If lexing out of a 'mapped buffer', where we pretend the +/// lexer buffer was all instantiated 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 SourceLocation GetMappedTokenLoc(Preprocessor &PP, + SourceLocation FileLoc, + unsigned CharNo, + unsigned TokLen) DISABLE_INLINE; +static SourceLocation GetMappedTokenLoc(Preprocessor &PP, + SourceLocation FileLoc, + unsigned CharNo, unsigned TokLen) { + assert(FileLoc.isMacroID() && "Must be an instantiation"); + + // Otherwise, we're lexing "mapped tokens". This is used for things like + // _Pragma handling. Combine the instantiation location of FileLoc with the + // spelling location. + SourceManager &SM = PP.getSourceManager(); + + // Create a new SLoc which is expanded from Instantiation(FileLoc) but whose + // characters come from spelling(FileLoc)+Offset. + SourceLocation SpellingLoc = SM.getSpellingLoc(FileLoc); + SpellingLoc = SpellingLoc.getFileLocWithOffset(CharNo); + + // Figure out the expansion loc range, which is the range covered by the + // original _Pragma(...) sequence. + std::pair<SourceLocation,SourceLocation> II = + SM.getImmediateInstantiationRange(FileLoc); + + return SM.createInstantiationLoc(SpellingLoc, II.first, II.second, TokLen); +} + +/// getSourceLocation - Return a source location identifier for the specified +/// offset in the current file. +SourceLocation Lexer::getSourceLocation(const char *Loc, + unsigned TokLen) const { + assert(Loc >= BufferStart && Loc <= BufferEnd && + "Location out of range for this buffer!"); + + // In the normal case, we're just lexing from a simple file buffer, return + // the file id from FileLoc with the offset specified. + unsigned CharNo = Loc-BufferStart; + if (FileLoc.isFileID()) + return FileLoc.getFileLocWithOffset(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->getFeatures().Trigraphs) { + if (!L->isLexingRawMode()) + L->Diag(CP-2, diag::trigraph_ignored); + return 0; + } + + if (!L->isLexingRawMode()) + L->Diag(CP-2, diag::trigraph_converted) << std::string()+Res; + return Res; +} + +/// getEscapedNewLineSize - Return the size of the specified escaped newline, +/// or 0 if it is not an escaped newline. P[-1] is known to be a "\" or a +/// trigraph equivalent on entry to this function. +unsigned Lexer::getEscapedNewLineSize(const char *Ptr) { + unsigned Size = 0; + while (isWhitespace(Ptr[Size])) { + ++Size; + + if (Ptr[Size-1] != '\n' && Ptr[Size-1] != '\r') + continue; + + // If this is a \r\n or \n\r, skip the other half. + if ((Ptr[Size] == '\r' || Ptr[Size] == '\n') && + Ptr[Size-1] != Ptr[Size]) + ++Size; + + return Size; + } + + // Not an escaped newline, must be a \t or something else. + return 0; +} + +/// SkipEscapedNewLines - If P points to an escaped newline (or a series of +/// them), skip over them and return the first non-escaped-newline found, +/// otherwise return P. +const char *Lexer::SkipEscapedNewLines(const char *P) { + while (1) { + const char *AfterEscape; + if (*P == '\\') { + AfterEscape = P+1; + } else if (*P == '?') { + // If not a trigraph for escape, bail out. + if (P[1] != '?' || P[2] != '/') + return P; + AfterEscape = P+3; + } else { + return P; + } + + unsigned NewLineSize = Lexer::getEscapedNewLineSize(AfterEscape); + if (NewLineSize == 0) return P; + P = AfterEscape+NewLineSize; + } +} + + +/// getCharAndSizeSlow - Peek a single 'character' from the specified buffer, +/// get its size, and return it. This is tricky in several cases: +/// 1. If currently at the start of a trigraph, we warn about the trigraph, +/// then either return the trigraph (skipping 3 chars) or the '?', +/// depending on whether trigraphs are enabled or not. +/// 2. If this is an escaped newline (potentially with whitespace between +/// the backslash and newline), implicitly skip the newline and return +/// the char after it. +/// 3. If this is a UCN, return it. FIXME: C++ UCN's? +/// +/// This handles the slow/uncommon case of the getCharAndSize method. Here we +/// know that we can accumulate into Size, and that we have already incremented +/// Ptr by Size bytes. +/// +/// NOTE: When this method is updated, getCharAndSizeSlowNoWarn (below) should +/// be updated to match. +/// +char Lexer::getCharAndSizeSlow(const char *Ptr, unsigned &Size, + Token *Tok) { + // If we have a slash, look for an escaped newline. + if (Ptr[0] == '\\') { + ++Size; + ++Ptr; +Slash: + // Common case, backslash-char where the char is not whitespace. + if (!isWhitespace(Ptr[0])) return '\\'; + + // See if we have optional whitespace characters followed by a 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 (EscapedNewLineSize != 1 && 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 : 0)) { + // Remember that this token needs to be cleaned. + if (Tok) Tok->setFlag(Token::NeedsCleaning); + + Ptr += 3; + Size += 3; + if (C == '\\') goto Slash; + return C; + } + } + + // If this is neither, return a single character. + ++Size; + return *Ptr; +} + + +/// getCharAndSizeSlowNoWarn - Handle the slow/uncommon case of the +/// getCharAndSizeNoWarn method. Here we know that we can accumulate into Size, +/// and that we have already incremented Ptr by Size bytes. +/// +/// NOTE: When this method is updated, getCharAndSizeSlow (above) should +/// be updated to match. +char Lexer::getCharAndSizeSlowNoWarn(const char *Ptr, unsigned &Size, + const LangOptions &Features) { + // 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, Features); + } + + // Otherwise, this is not an escaped newline, just return the slash. + return '\\'; + } + + // If this is a trigraph, process it. + if (Features.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. +//===----------------------------------------------------------------------===// + +void Lexer::LexIdentifier(Token &Result, const char *CurPtr) { + // Match [_A-Za-z0-9]*, we have already matched [_A-Za-z$] + unsigned Size; + unsigned char C = *CurPtr++; + while (isIdentifierBody(C)) { + C = *CurPtr++; + } + --CurPtr; // Back up over the skipped character. + + // Fast path, no $,\,? in identifier found. '\' might be an escaped newline + // or UCN, and ? might be a trigraph for '\', an escaped newline or UCN. + // FIXME: UCNs. + if (C != '\\' && C != '?' && (C != '$' || !Features.DollarIdents)) { +FinishIdentifier: + const char *IdStart = BufferPtr; + FormTokenWithChars(Result, CurPtr, tok::identifier); + + // If we are in raw mode, return this identifier raw. There is no need to + // look up identifier information or attempt to macro expand it. + if (LexingRawMode) return; + + // Fill in Result.IdentifierInfo, looking up the identifier in the + // identifier table. + IdentifierInfo *II = PP->LookUpIdentifierInfo(Result, IdStart); + + // Change the kind of this identifier to the appropriate token kind, e.g. + // turning "for" into a keyword. + Result.setKind(II->getTokenID()); + + // Finally, now that we know we have an identifier, pass this off to the + // preprocessor, which may macro expand it or something. + if (II->isHandleIdentifierCase()) + PP->HandleIdentifier(Result); + return; + } + + // Otherwise, $,\,? in identifier found. Enter slower path. + + C = getCharAndSize(CurPtr, Size); + while (1) { + if (C == '$') { + // If we hit a $ and they are not supported in identifiers, we are done. + if (!Features.DollarIdents) goto FinishIdentifier; + + // Otherwise, emit a diagnostic and continue. + if (!isLexingRawMode()) + Diag(CurPtr, diag::ext_dollar_in_identifier); + CurPtr = ConsumeChar(CurPtr, Size, Result); + C = getCharAndSize(CurPtr, Size); + continue; + } else if (!isIdentifierBody(C)) { // FIXME: UCNs. + // Found end of identifier. + goto FinishIdentifier; + } + + // Otherwise, this character is good, consume it. + CurPtr = ConsumeChar(CurPtr, Size, Result); + + C = getCharAndSize(CurPtr, Size); + while (isIdentifierBody(C)) { // FIXME: UCNs. + CurPtr = ConsumeChar(CurPtr, Size, Result); + C = getCharAndSize(CurPtr, Size); + } + } +} + + +/// LexNumericConstant - Lex the remainder of a integer or floating point +/// constant. From[-1] is the first character lexed. Return the end of the +/// constant. +void Lexer::LexNumericConstant(Token &Result, const char *CurPtr) { + unsigned Size; + char C = getCharAndSize(CurPtr, Size); + char PrevCh = 0; + while (isNumberBody(C)) { // FIXME: UCNs? + CurPtr = ConsumeChar(CurPtr, Size, Result); + PrevCh = C; + C = getCharAndSize(CurPtr, Size); + } + + // If we fell out, check for a sign, due to 1e+12. If we have one, continue. + if ((C == '-' || C == '+') && (PrevCh == 'E' || PrevCh == 'e')) + return LexNumericConstant(Result, ConsumeChar(CurPtr, Size, Result)); + + // If we have a hex FP constant, continue. + if ((C == '-' || C == '+') && (PrevCh == 'P' || PrevCh == 'p')) + return LexNumericConstant(Result, ConsumeChar(CurPtr, Size, Result)); + + // Update the location of token as well as BufferPtr. + const char *TokStart = BufferPtr; + FormTokenWithChars(Result, CurPtr, tok::numeric_constant); + Result.setLiteralData(TokStart); +} + +/// LexStringLiteral - Lex the remainder of a string literal, after having lexed +/// either " or L". +void Lexer::LexStringLiteral(Token &Result, const char *CurPtr, bool Wide) { + const char *NulCharacter = 0; // Does this string contain the \0 character? + + char C = getAndAdvanceChar(CurPtr, Result); + while (C != '"') { + // Skip escaped characters. + if (C == '\\') { + // Skip the escaped character. + C = getAndAdvanceChar(CurPtr, Result); + } else if (C == '\n' || C == '\r' || // Newline. + (C == 0 && CurPtr-1 == BufferEnd)) { // End of file. + if (!isLexingRawMode() && !Features.AsmPreprocessor) + Diag(BufferPtr, diag::err_unterminated_string); + FormTokenWithChars(Result, CurPtr-1, tok::unknown); + return; + } else if (C == 0) { + NulCharacter = CurPtr-1; + } + C = getAndAdvanceChar(CurPtr, Result); + } + + // If a nul character existed in the string, warn about it. + if (NulCharacter && !isLexingRawMode()) + Diag(NulCharacter, diag::null_in_string); + + // Update the location of the token as well as the BufferPtr instance var. + const char *TokStart = BufferPtr; + FormTokenWithChars(Result, CurPtr, + Wide ? tok::wide_string_literal : tok::string_literal); + Result.setLiteralData(TokStart); +} + +/// LexAngledStringLiteral - Lex the remainder of an angled string literal, +/// after having lexed the '<' character. This is used for #include filenames. +void Lexer::LexAngledStringLiteral(Token &Result, const char *CurPtr) { + const char *NulCharacter = 0; // Does this string contain the \0 character? + const char *AfterLessPos = CurPtr; + char C = getAndAdvanceChar(CurPtr, Result); + while (C != '>') { + // Skip escaped characters. + if (C == '\\') { + // Skip the escaped character. + C = getAndAdvanceChar(CurPtr, Result); + } else if (C == '\n' || C == '\r' || // Newline. + (C == 0 && CurPtr-1 == BufferEnd)) { // End of file. + // If the filename is unterminated, then it must just be a lone < + // character. Return this as such. + FormTokenWithChars(Result, AfterLessPos, tok::less); + return; + } else if (C == 0) { + NulCharacter = CurPtr-1; + } + C = getAndAdvanceChar(CurPtr, Result); + } + + // If a nul character existed in the string, warn about it. + if (NulCharacter && !isLexingRawMode()) + Diag(NulCharacter, diag::null_in_string); + + // Update the location of token as well as BufferPtr. + const char *TokStart = BufferPtr; + FormTokenWithChars(Result, CurPtr, tok::angle_string_literal); + Result.setLiteralData(TokStart); +} + + +/// LexCharConstant - Lex the remainder of a character constant, after having +/// lexed either ' or L'. +void Lexer::LexCharConstant(Token &Result, const char *CurPtr) { + const char *NulCharacter = 0; // Does this character contain the \0 character? + + // Handle the common case of 'x' and '\y' efficiently. + char C = getAndAdvanceChar(CurPtr, Result); + if (C == '\'') { + if (!isLexingRawMode() && !Features.AsmPreprocessor) + Diag(BufferPtr, diag::err_empty_character); + FormTokenWithChars(Result, CurPtr, tok::unknown); + return; + } else if (C == '\\') { + // Skip the escaped character. + // FIXME: UCN's. + C = getAndAdvanceChar(CurPtr, Result); + } + + if (C && C != '\n' && C != '\r' && CurPtr[0] == '\'') { + ++CurPtr; + } else { + // Fall back on generic code for embedded nulls, newlines, wide chars. + do { + // Skip escaped characters. + if (C == '\\') { + // Skip the escaped character. + C = getAndAdvanceChar(CurPtr, Result); + } else if (C == '\n' || C == '\r' || // Newline. + (C == 0 && CurPtr-1 == BufferEnd)) { // End of file. + if (!isLexingRawMode() && !Features.AsmPreprocessor) + Diag(BufferPtr, diag::err_unterminated_char); + FormTokenWithChars(Result, CurPtr-1, tok::unknown); + return; + } else if (C == 0) { + NulCharacter = CurPtr-1; + } + C = getAndAdvanceChar(CurPtr, Result); + } while (C != '\''); + } + + if (NulCharacter && !isLexingRawMode()) + Diag(NulCharacter, diag::null_in_char); + + // Update the location of token as well as BufferPtr. + const char *TokStart = BufferPtr; + FormTokenWithChars(Result, CurPtr, tok::char_constant); + Result.setLiteralData(TokStart); +} + +/// SkipWhitespace - Efficiently skip over a series of whitespace characters. +/// Update BufferPtr to point to the next non-whitespace character and return. +/// +/// This method forms a token and returns true if KeepWhitespaceMode is enabled. +/// +bool Lexer::SkipWhitespace(Token &Result, const char *CurPtr) { + // Whitespace - Skip it, then return the token after the whitespace. + unsigned char Char = *CurPtr; // Skip consequtive spaces efficiently. + while (1) { + // Skip horizontal whitespace very aggressively. + while (isHorizontalWhitespace(Char)) + Char = *++CurPtr; + + // Otherwise if we have something other than whitespace, we're done. + if (Char != '\n' && Char != '\r') + break; + + if (ParsingPreprocessorDirective) { + // End of preprocessor directive line, let LexTokenInternal handle this. + BufferPtr = CurPtr; + return false; + } + + // ok, but handle newline. + // The returned token is at the start of the line. + Result.setFlag(Token::StartOfLine); + // No leading whitespace seen so far. + Result.clearFlag(Token::LeadingSpace); + Char = *++CurPtr; + } + + // If this isn't immediately after a newline, there is leading space. + char PrevChar = CurPtr[-1]; + if (PrevChar != '\n' && PrevChar != '\r') + Result.setFlag(Token::LeadingSpace); + + // If the client wants us to return whitespace, return it now. + if (isKeepWhitespaceMode()) { + FormTokenWithChars(Result, CurPtr, tok::unknown); + return true; + } + + BufferPtr = CurPtr; + return false; +} + +// SkipBCPLComment - We have just read the // characters from input. Skip until +// we find the newline character thats terminate the comment. Then update +/// BufferPtr and return. If we're in KeepCommentMode, this will form the token +/// and return true. +bool Lexer::SkipBCPLComment(Token &Result, const char *CurPtr) { + // If BCPL comments aren't explicitly enabled for this language, emit an + // extension warning. + if (!Features.BCPLComment && !isLexingRawMode()) { + Diag(BufferPtr, diag::ext_bcpl_comment); + + // Mark them enabled so we only emit one warning for this translation + // unit. + Features.BCPLComment = true; + } + + // Scan over the body of the comment. The common case, when scanning, is that + // the comment contains normal ascii characters with nothing interesting in + // them. As such, optimize for this case with the inner loop. + char C; + do { + C = *CurPtr; + // FIXME: Speedup BCPL comment lexing. Just scan for a \n or \r character. + // If we find a \n character, scan backwards, checking to see if it's an + // escaped newline, like we do for block comments. + + // Skip over characters in the fast loop. + while (C != 0 && // Potentially EOF. + C != '\\' && // Potentially escaped newline. + C != '?' && // Potentially trigraph. + C != '\n' && C != '\r') // Newline or DOS-style newline. + C = *++CurPtr; + + // If this is a newline, we're done. + if (C == '\n' || C == '\r') + break; // Found the newline? Break out! + + // 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 the char that we finally got was a \n, then we must have had something + // like \<newline><newline>. We don't want to have consumed the second + // newline, we want CurPtr, to end up pointing to it down below. + if (C == '\n' || C == '\r') { + --CurPtr; + C = 'x'; // doesn't matter what this is. + } + + // If we read multiple characters, and one of those characters was a \r or + // \n, then we had an escaped newline within the comment. Emit diagnostic + // unless the next line is also a // comment. + if (CurPtr != OldPtr+1 && C != '/' && CurPtr[0] != '/') { + for (; OldPtr != CurPtr; ++OldPtr) + if (OldPtr[0] == '\n' || OldPtr[0] == '\r') { + // Okay, we found a // comment that ends in a newline, if the next + // line is also a // comment, but has spaces, don't emit a diagnostic. + if (isspace(C)) { + const char *ForwardPtr = CurPtr; + while (isspace(*ForwardPtr)) // Skip whitespace. + ++ForwardPtr; + if (ForwardPtr[0] == '/' && ForwardPtr[1] == '/') + break; + } + + if (!isLexingRawMode()) + Diag(OldPtr-1, diag::ext_multi_line_bcpl_comment); + break; + } + } + + if (CurPtr == BufferEnd+1) { --CurPtr; break; } + } while (C != '\n' && C != '\r'); + + // Found but did not consume the newline. + + // If we are returning comments as tokens, return this comment as a token. + if (inKeepCommentMode()) + return SaveBCPLComment(Result, CurPtr); + + // If we are inside a preprocessor directive and we see the end of line, + // return immediately, so that the lexer can return this as an EOM token. + if (ParsingPreprocessorDirective || CurPtr == BufferEnd) { + BufferPtr = CurPtr; + return false; + } + + // Otherwise, eat the \n character. We don't care if this is a \n\r or + // \r\n sequence. This is an efficiency hack (because we know the \n can't + // contribute to another token), it isn't needed for correctness. Note that + // this is ok even in KeepWhitespaceMode, because we would have returned the + /// comment above in that mode. + ++CurPtr; + + // The next returned token is at the start of the line. + Result.setFlag(Token::StartOfLine); + // No leading whitespace seen so far. + Result.clearFlag(Token::LeadingSpace); + BufferPtr = CurPtr; + return false; +} + +/// SaveBCPLComment - If in save-comment mode, package up this BCPL comment in +/// an appropriate way and return it. +bool Lexer::SaveBCPLComment(Token &Result, const char *CurPtr) { + // If we're not in a preprocessor directive, just return the // comment + // directly. + FormTokenWithChars(Result, CurPtr, tok::comment); + + if (!ParsingPreprocessorDirective) + return true; + + // If this BCPL-style comment is in a macro definition, transmogrify it into + // a C-style block comment. + std::string Spelling = PP->getSpelling(Result); + assert(Spelling[0] == '/' && Spelling[1] == '/' && "Not bcpl comment?"); + Spelling[1] = '*'; // Change prefix to "/*". + Spelling += "*/"; // add suffix. + + Result.setKind(tok::comment); + PP->CreateString(&Spelling[0], Spelling.size(), Result, + Result.getLocation()); + 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->getFeatures().Trigraphs) { + if (!L->isLexingRawMode()) + L->Diag(CurPtr, diag::trigraph_ignored_block_comment); + return false; + } + if (!L->isLexingRawMode()) + L->Diag(CurPtr, diag::trigraph_ends_block_comment); + } + + // Warn about having an escaped newline between the */ characters. + if (!L->isLexingRawMode()) + L->Diag(CurPtr, diag::escaped_newline_block_comment_end); + + // If there was space between the backslash and newline, warn about it. + if (HasSpace && !L->isLexingRawMode()) + L->Diag(CurPtr, diag::backslash_newline_space); + + return true; +} + +#ifdef __SSE2__ +#include <emmintrin.h> +#elif __ALTIVEC__ +#include <altivec.h> +#undef bool +#endif + +/// SkipBlockComment - We have just read the /* characters from input. Read +/// until we find the */ characters that terminate the comment. Note that we +/// don't bother decoding trigraphs or escaped newlines in block comments, +/// because they cannot cause the comment to end. The only thing that can +/// happen is the comment could end with an escaped newline between the */ end +/// of comment. +/// +/// If KeepCommentMode is enabled, this forms a token from the comment and +/// returns true. +bool Lexer::SkipBlockComment(Token &Result, const char *CurPtr) { + // Scan one character past where we should, looking for a '/' character. Once + // we find it, check to see if it was preceeded by a *. This common + // optimization helps people who like to put a lot of * characters in their + // comments. + + // The first character we get with newlines and trigraphs skipped to handle + // the degenerate /*/ case below correctly if the * has an escaped newline + // after it. + unsigned CharSize; + unsigned char C = getCharAndSize(CurPtr, CharSize); + CurPtr += CharSize; + if (C == 0 && CurPtr == BufferEnd+1) { + if (!isLexingRawMode()) + Diag(BufferPtr, diag::err_unterminated_block_comment); + --CurPtr; + + // KeepWhitespaceMode should return this broken comment as a token. Since + // it isn't a well formed comment, just return it as an 'unknown' token. + if (isKeepWhitespaceMode()) { + FormTokenWithChars(Result, CurPtr, tok::unknown); + return true; + } + + BufferPtr = CurPtr; + return false; + } + + // Check to see if the first character after the '/*' is another /. If so, + // then this slash does not end the block comment, it is part of it. + if (C == '/') + C = *CurPtr++; + + while (1) { + // Skip over all non-interesting characters until we find end of buffer or a + // (probably ending) '/' character. + if (CurPtr + 24 < BufferEnd) { + // 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_set_epi8('/', '/', '/', '/', '/', '/', '/', '/', + '/', '/', '/', '/', '/', '/', '/', '/'); + while (CurPtr+16 <= BufferEnd && + _mm_movemask_epi8(_mm_cmpeq_epi8(*(__m128i*)CurPtr, Slashes)) == 0) + CurPtr += 16; +#elif __ALTIVEC__ + __vector unsigned char Slashes = { + '/', '/', '/', '/', '/', '/', '/', '/', + '/', '/', '/', '/', '/', '/', '/', '/' + }; + while (CurPtr+16 <= BufferEnd && + !vec_any_eq(*(vector unsigned char*)CurPtr, Slashes)) + CurPtr += 16; +#else + // Scan for '/' quickly. Many block comments are very large. + while (CurPtr[0] != '/' && + CurPtr[1] != '/' && + CurPtr[2] != '/' && + CurPtr[3] != '/' && + CurPtr+4 < BufferEnd) { + CurPtr += 4; + } +#endif + + // It has to be one of the bytes scanned, increment to it and read one. + C = *CurPtr++; + } + + // Loop to scan the remainder. + while (C != '/' && C != '\0') + C = *CurPtr++; + + FoundSlash: + if (C == '/') { + 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; + } + C = *CurPtr++; + } + + // If we are returning comments as tokens, return this comment as a token. + if (inKeepCommentMode()) { + FormTokenWithChars(Result, CurPtr, tok::comment); + return true; + } + + // It is common for the tokens immediately after a /**/ comment to be + // whitespace. Instead of going through the big switch, handle it + // efficiently now. This is safe even in KeepWhitespaceMode because we would + // have already returned above with the comment as a token. + if (isHorizontalWhitespace(*CurPtr)) { + Result.setFlag(Token::LeadingSpace); + SkipWhitespace(Result, CurPtr+1); + return false; + } + + // Otherwise, just return so that the next character will be lexed as a token. + BufferPtr = CurPtr; + Result.setFlag(Token::LeadingSpace); + return false; +} + +//===----------------------------------------------------------------------===// +// Primary Lexing Entry Points +//===----------------------------------------------------------------------===// + +/// ReadToEndOfLine - Read the rest of the current preprocessor line as an +/// uninterpreted string. This switches the lexer out of directive mode. +std::string Lexer::ReadToEndOfLine() { + assert(ParsingPreprocessorDirective && ParsingFilename == false && + "Must be in a preprocessing directive!"); + std::string Result; + Token Tmp; + + // CurPtr - Cache BufferPtr in an automatic variable. + const char *CurPtr = BufferPtr; + while (1) { + char Char = getAndAdvanceChar(CurPtr, Tmp); + switch (Char) { + default: + Result += Char; + break; + case 0: // Null. + // Found end of file? + if (CurPtr-1 != BufferEnd) { + // Nope, normal character, continue. + Result += Char; + break; + } + // FALL THROUGH. + case '\r': + case '\n': + // Okay, we found the end of the line. First, back up past the \0, \r, \n. + assert(CurPtr[-1] == Char && "Trigraphs for newline?"); + BufferPtr = CurPtr-1; + + // Next, lex the character, which should handle the EOM transition. + Lex(Tmp); + assert(Tmp.is(tok::eom) && "Unexpected token!"); + + // Finally, we're done, return the string we found. + return Result; + } + } +} + +/// LexEndOfFile - CurPtr points to the end of this file. Handle this +/// condition, reporting diagnostics and handling other edge cases as required. +/// This returns true if Result contains a token, false if PP.Lex should be +/// called again. +bool Lexer::LexEndOfFile(Token &Result, const char *CurPtr) { + // If we hit the end of the file while parsing a preprocessor directive, + // end the preprocessor directive first. The next token returned will + // then be the end of file. + if (ParsingPreprocessorDirective) { + // Done parsing the "line". + ParsingPreprocessorDirective = false; + // Update the location of token as well as BufferPtr. + FormTokenWithChars(Result, CurPtr, tok::eom); + + // Restore comment saving mode, in case it was disabled for directive. + SetCommentRetentionState(PP->getCommentRetentionState()); + return true; // Have a token. + } + + // If we are in raw mode, return this event as an EOF token. Let the caller + // that put us in raw mode handle the event. + if (isLexingRawMode()) { + Result.startToken(); + BufferPtr = BufferEnd; + FormTokenWithChars(Result, BufferEnd, tok::eof); + return true; + } + + // Otherwise, issue diagnostics for unterminated #if and missing newline. + + // If we are in a #if directive, emit an error. + while (!ConditionalStack.empty()) { + PP->Diag(ConditionalStack.back().IfLoc, + diag::err_pp_unterminated_conditional); + ConditionalStack.pop_back(); + } + + // C99 5.1.1.2p2: If the file is non-empty and didn't end in a newline, issue + // a pedwarn. + if (CurPtr != BufferStart && (CurPtr[-1] != '\n' && CurPtr[-1] != '\r')) + Diag(BufferEnd, diag::ext_no_newline_eof) + << CodeModificationHint::CreateInsertion(getSourceLocation(BufferEnd), + "\n"); + + BufferPtr = CurPtr; + + // Finally, let the preprocessor handle this. + return PP->HandleEndOfFile(Result); +} + +/// isNextPPTokenLParen - Return 1 if the next unexpanded token lexed from +/// the specified lexer will return a tok::l_paren token, 0 if it is something +/// else and 2 if there are no more tokens in the buffer controlled by the +/// lexer. +unsigned Lexer::isNextPPTokenLParen() { + assert(!LexingRawMode && "How can we expand a macro from a skipping buffer?"); + + // Switch to 'skipping' mode. This will ensure that we can lex a token + // without emitting diagnostics, disables macro expansion, and will cause EOF + // to return an EOF token instead of popping the include stack. + LexingRawMode = true; + + // Save state that can be changed while lexing so that we can restore it. + const char *TmpBufferPtr = BufferPtr; + bool inPPDirectiveMode = ParsingPreprocessorDirective; + + Token Tok; + Tok.startToken(); + LexTokenInternal(Tok); + + // Restore state that may have changed. + BufferPtr = TmpBufferPtr; + ParsingPreprocessorDirective = inPPDirectiveMode; + + // Restore the lexer back to non-skipping mode. + LexingRawMode = false; + + if (Tok.is(tok::eof)) + return 2; + return Tok.is(tok::l_paren); +} + + +/// 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. Return true if an error +/// occurred and compilation should terminate, false if normal. This returns a +/// preprocessing token, not a normal token, as such, it is an internal +/// interface. It assumes that the Flags of result have been cleared before +/// calling this. +void Lexer::LexTokenInternal(Token &Result) { +LexNextToken: + // New token, can't need cleaning yet. + Result.clearFlag(Token::NeedsCleaning); + Result.setIdentifierInfo(0); + + // CurPtr - Cache BufferPtr in an automatic variable. + const char *CurPtr = BufferPtr; + + // Small amounts of horizontal whitespace is very common between tokens. + if ((*CurPtr == ' ') || (*CurPtr == '\t')) { + ++CurPtr; + while ((*CurPtr == ' ') || (*CurPtr == '\t')) + ++CurPtr; + + // If we are keeping whitespace and other tokens, just return what we just + // skipped. The next lexer invocation will return the token after the + // whitespace. + if (isKeepWhitespaceMode()) { + FormTokenWithChars(Result, CurPtr, tok::unknown); + return; + } + + BufferPtr = CurPtr; + Result.setFlag(Token::LeadingSpace); + } + + unsigned SizeTmp, SizeTmp2; // Temporaries for use in cases below. + + // Read a character, advancing over it. + char Char = getAndAdvanceChar(CurPtr, Result); + tok::TokenKind Kind; + + switch (Char) { + case 0: // Null. + // Found end of file? + if (CurPtr-1 == BufferEnd) { + // Read the PP instance variable into an automatic variable, because + // LexEndOfFile will often delete 'this'. + Preprocessor *PPCache = PP; + if (LexEndOfFile(Result, CurPtr-1)) // Retreat back into the file. + return; // Got a token to return. + assert(PPCache && "Raw buffer::LexEndOfFile should return a token"); + return PPCache->Lex(Result); + } + + if (!isLexingRawMode()) + Diag(CurPtr-1, diag::null_in_file); + Result.setFlag(Token::LeadingSpace); + if (SkipWhitespace(Result, CurPtr)) + return; // KeepWhitespaceMode + + goto LexNextToken; // GCC isn't tail call eliminating. + case '\n': + case '\r': + // If we are inside a preprocessor directive and we see the end of line, + // we know we are done with the directive, so return an EOM token. + if (ParsingPreprocessorDirective) { + // Done parsing the "line". + ParsingPreprocessorDirective = false; + + // Restore comment saving mode, in case it was disabled for directive. + SetCommentRetentionState(PP->getCommentRetentionState()); + + // Since we consumed a newline, we are back at the start of a line. + IsAtStartOfLine = true; + + Kind = tok::eom; + break; + } + // The returned token is at the start of the line. + Result.setFlag(Token::StartOfLine); + // No leading whitespace seen so far. + Result.clearFlag(Token::LeadingSpace); + + if (SkipWhitespace(Result, CurPtr)) + return; // KeepWhitespaceMode + goto LexNextToken; // GCC isn't tail call eliminating. + case ' ': + case '\t': + case '\f': + case '\v': + SkipHorizontalWhitespace: + Result.setFlag(Token::LeadingSpace); + if (SkipWhitespace(Result, CurPtr)) + return; // KeepWhitespaceMode + + SkipIgnoredUnits: + CurPtr = BufferPtr; + + // If the next token is obviously a // or /* */ comment, skip it efficiently + // too (without going through the big switch stmt). + if (CurPtr[0] == '/' && CurPtr[1] == '/' && !inKeepCommentMode() && + Features.BCPLComment) { + SkipBCPLComment(Result, CurPtr+2); + goto SkipIgnoredUnits; + } else if (CurPtr[0] == '/' && CurPtr[1] == '*' && !inKeepCommentMode()) { + SkipBlockComment(Result, CurPtr+2); + goto SkipIgnoredUnits; + } else if (isHorizontalWhitespace(*CurPtr)) { + goto SkipHorizontalWhitespace; + } + goto LexNextToken; // GCC isn't tail call eliminating. + + // C99 6.4.4.1: Integer Constants. + // C99 6.4.4.2: Floating Constants. + case '0': case '1': case '2': case '3': case '4': + case '5': case '6': case '7': case '8': case '9': + // Notify MIOpt that we read a non-whitespace/non-comment token. + MIOpt.ReadToken(); + return LexNumericConstant(Result, CurPtr); + + case '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), + true); + + // Wide character constant. + if (Char == '\'') + return LexCharConstant(Result, ConsumeChar(CurPtr, SizeTmp, Result)); + // FALL THROUGH, treating L like the start of an identifier. + + // C99 6.4.2: Identifiers. + case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': case 'G': + case 'H': case 'I': case 'J': case 'K': /*'L'*/case 'M': case 'N': + case 'O': case 'P': case 'Q': case 'R': case 'S': case 'T': case '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': case '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 (Features.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); + + // C99 6.4.5: String Literals. + case '"': + // Notify MIOpt that we read a non-whitespace/non-comment token. + MIOpt.ReadToken(); + return LexStringLiteral(Result, CurPtr, false); + + // 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 (Features.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 == '>' && Features.CPlusPlus && + getCharAndSize(CurPtr+SizeTmp, SizeTmp2) == '*') { // C++ ->* + CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result), + SizeTmp2, Result); + Kind = tok::arrowstar; + } else if (Char == '>') { // -> + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + Kind = tok::arrow; + } else if (Char == '=') { // -= + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + Kind = tok::minusequal; + } else { + Kind = tok::minus; + } + break; + case '~': + Kind = tok::tilde; + break; + case '!': + if (getCharAndSize(CurPtr, SizeTmp) == '=') { + Kind = tok::exclaimequal; + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + } else { + Kind = tok::exclaim; + } + break; + case '/': + // 6.4.9: Comments + Char = getCharAndSize(CurPtr, SizeTmp); + if (Char == '/') { // BCPL comment. + // Even if BCPL comments are disabled (e.g. in C89 mode), we generally + // want to lex this as a comment. There is one problem with this though, + // that in one particular corner case, this can change the behavior of the + // resultant program. For example, In "foo //**/ bar", C89 would lex + // this as "foo / bar" and langauges with BCPL comments would lex it as + // "foo". Check to see if the character after the second slash is a '*'. + // If so, we will lex that as a "/" instead of the start of a comment. + if (Features.BCPLComment || + getCharAndSize(CurPtr+SizeTmp, SizeTmp2) != '*') { + if (SkipBCPLComment(Result, ConsumeChar(CurPtr, SizeTmp, Result))) + return; // KeepCommentMode + + // It is common for the tokens immediately after a // comment to be + // whitespace (indentation for the next line). Instead of going through + // the big switch, handle it efficiently now. + goto SkipIgnoredUnits; + } + } + + if (Char == '*') { // /**/ comment. + if (SkipBlockComment(Result, ConsumeChar(CurPtr, SizeTmp, Result))) + return; // KeepCommentMode + goto LexNextToken; // GCC isn't tail call eliminating. + } + + if (Char == '=') { + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + Kind = tok::slashequal; + } else { + Kind = tok::slash; + } + break; + case '%': + Char = getCharAndSize(CurPtr, SizeTmp); + if (Char == '=') { + Kind = tok::percentequal; + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + } else if (Features.Digraphs && Char == '>') { + Kind = tok::r_brace; // '%>' -> '}' + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + } else if (Features.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 == '@' && Features.Microsoft) { // %:@ -> #@ -> Charize + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + if (!isLexingRawMode()) + Diag(BufferPtr, diag::charize_microsoft_ext); + Kind = tok::hashat; + } else { // '%:' -> '#' + // We parsed a # character. If this occurs at the start of the line, + // it's actually the start of a preprocessing directive. Callback to + // the preprocessor to handle it. + // FIXME: -fpreprocessed mode?? + if (Result.isAtStartOfLine() && !LexingRawMode && !Is_PragmaLexer) { + FormTokenWithChars(Result, CurPtr, tok::hash); + PP->HandleDirective(Result); + + // As an optimization, if the preprocessor didn't switch lexers, tail + // recurse. + if (PP->isCurrentLexer(this)) { + // Start a new token. If this is a #include or something, the PP may + // want us starting at the beginning of the line again. If so, set + // the StartOfLine flag. + if (IsAtStartOfLine) { + Result.setFlag(Token::StartOfLine); + IsAtStartOfLine = false; + } + goto LexNextToken; // GCC isn't tail call eliminating. + } + + return PP->Lex(Result); + } + + Kind = tok::hash; + } + } else { + Kind = tok::percent; + } + break; + case '<': + Char = getCharAndSize(CurPtr, SizeTmp); + if (ParsingFilename) { + return LexAngledStringLiteral(Result, CurPtr); + } else if (Char == '<' && + getCharAndSize(CurPtr+SizeTmp, SizeTmp2) == '=') { + Kind = tok::lesslessequal; + CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result), + SizeTmp2, Result); + } else if (Char == '<') { + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + Kind = tok::lessless; + } else if (Char == '=') { + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + Kind = tok::lessequal; + } else if (Features.Digraphs && Char == ':') { // '<:' -> '[' + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + Kind = tok::l_square; + } else if (Features.Digraphs && Char == '%') { // '<%' -> '{' + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + Kind = tok::l_brace; + } else { + Kind = tok::less; + } + break; + case '>': + Char = getCharAndSize(CurPtr, SizeTmp); + if (Char == '=') { + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + Kind = tok::greaterequal; + } else if (Char == '>' && + getCharAndSize(CurPtr+SizeTmp, SizeTmp2) == '=') { + CurPtr = ConsumeChar(ConsumeChar(CurPtr, SizeTmp, Result), + SizeTmp2, Result); + Kind = tok::greatergreaterequal; + } else if (Char == '>') { + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + Kind = tok::greatergreater; + } else { + Kind = tok::greater; + } + break; + case '^': + Char = getCharAndSize(CurPtr, SizeTmp); + if (Char == '=') { + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + Kind = tok::caretequal; + } else { + Kind = tok::caret; + } + break; + case '|': + Char = getCharAndSize(CurPtr, SizeTmp); + if (Char == '=') { + Kind = tok::pipeequal; + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + } else if (Char == '|') { + Kind = tok::pipepipe; + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + } else { + Kind = tok::pipe; + } + break; + case ':': + Char = getCharAndSize(CurPtr, SizeTmp); + if (Features.Digraphs && Char == '>') { + Kind = tok::r_square; // ':>' -> ']' + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + } else if (Features.CPlusPlus && Char == ':') { + Kind = tok::coloncolon; + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + } else { + Kind = tok::colon; + } + break; + case ';': + Kind = tok::semi; + break; + case '=': + Char = getCharAndSize(CurPtr, SizeTmp); + if (Char == '=') { + 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 == '@' && Features.Microsoft) { // #@ -> Charize + Kind = tok::hashat; + if (!isLexingRawMode()) + Diag(BufferPtr, diag::charize_microsoft_ext); + CurPtr = ConsumeChar(CurPtr, SizeTmp, Result); + } else { + // We parsed a # character. If this occurs at the start of the line, + // it's actually the start of a preprocessing directive. Callback to + // the preprocessor to handle it. + // FIXME: -fpreprocessed mode?? + if (Result.isAtStartOfLine() && !LexingRawMode && !Is_PragmaLexer) { + FormTokenWithChars(Result, CurPtr, tok::hash); + PP->HandleDirective(Result); + + // As an optimization, if the preprocessor didn't switch lexers, tail + // recurse. + if (PP->isCurrentLexer(this)) { + // Start a new token. If this is a #include or something, the PP may + // want us starting at the beginning of the line again. If so, set + // the StartOfLine flag. + if (IsAtStartOfLine) { + Result.setFlag(Token::StartOfLine); + IsAtStartOfLine = false; + } + goto LexNextToken; // GCC isn't tail call eliminating. + } + return PP->Lex(Result); + } + + Kind = tok::hash; + } + break; + + case '@': + // Objective C support. + if (CurPtr[-1] == '@' && Features.ObjC1) + Kind = tok::at; + else + Kind = tok::unknown; + break; + + case '\\': + // FIXME: UCN's. + // FALL THROUGH. + default: + Kind = tok::unknown; + break; + } + + // Notify MIOpt that we read a non-whitespace/non-comment token. + MIOpt.ReadToken(); + + // Update the location of token as well as BufferPtr. + FormTokenWithChars(Result, CurPtr, Kind); +} |
