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diff --git a/clang-r353983/include/clang/Lex/Lexer.h b/clang-r353983/include/clang/Lex/Lexer.h new file mode 100644 index 00000000..4a8a0f6f --- /dev/null +++ b/clang-r353983/include/clang/Lex/Lexer.h @@ -0,0 +1,754 @@ +//===- Lexer.h - C Language Family Lexer ------------------------*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This file defines the Lexer interface. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_CLANG_LEX_LEXER_H +#define LLVM_CLANG_LEX_LEXER_H + +#include "clang/Basic/LangOptions.h" +#include "clang/Basic/SourceLocation.h" +#include "clang/Basic/TokenKinds.h" +#include "clang/Lex/PreprocessorLexer.h" +#include "clang/Lex/Token.h" +#include "llvm/ADT/Optional.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/StringRef.h" +#include <cassert> +#include <cstdint> +#include <string> + +namespace llvm { + +class MemoryBuffer; + +} // namespace llvm + +namespace clang { + +class DiagnosticBuilder; +class Preprocessor; +class SourceManager; + +/// ConflictMarkerKind - Kinds of conflict marker which the lexer might be +/// recovering from. +enum ConflictMarkerKind { + /// Not within a conflict marker. + CMK_None, + + /// A normal or diff3 conflict marker, initiated by at least 7 "<"s, + /// separated by at least 7 "="s or "|"s, and terminated by at least 7 ">"s. + CMK_Normal, + + /// A Perforce-style conflict marker, initiated by 4 ">"s, + /// separated by 4 "="s, and terminated by 4 "<"s. + CMK_Perforce +}; + +/// Describes the bounds (start, size) of the preamble and a flag required by +/// PreprocessorOptions::PrecompiledPreambleBytes. +/// The preamble includes the BOM, if any. +struct PreambleBounds { + /// Size of the preamble in bytes. + unsigned Size; + + /// Whether the preamble ends at the start of a new line. + /// + /// Used to inform the lexer as to whether it's starting at the beginning of + /// a line after skipping the preamble. + bool PreambleEndsAtStartOfLine; + + PreambleBounds(unsigned Size, bool PreambleEndsAtStartOfLine) + : Size(Size), PreambleEndsAtStartOfLine(PreambleEndsAtStartOfLine) {} +}; + +/// Lexer - This provides a simple interface that turns a text buffer into a +/// stream of tokens. This provides no support for file reading or buffering, +/// or buffering/seeking of tokens, only forward lexing is supported. It relies +/// on the specified Preprocessor object to handle preprocessor directives, etc. +class Lexer : public PreprocessorLexer { + friend class Preprocessor; + + void anchor() override; + + //===--------------------------------------------------------------------===// + // Constant configuration values for this lexer. + + // Start of the buffer. + const char *BufferStart; + + // End of the buffer. + const char *BufferEnd; + + // Location for start of file. + SourceLocation FileLoc; + + // LangOpts enabled by this language (cache). + LangOptions LangOpts; + + // True if lexer for _Pragma handling. + bool Is_PragmaLexer; + + //===--------------------------------------------------------------------===// + // Context-specific lexing flags set by the preprocessor. + // + + /// ExtendedTokenMode - The lexer can optionally keep comments and whitespace + /// and return them as tokens. This is used for -C and -CC modes, and + /// whitespace preservation can be useful for some clients that want to lex + /// the file in raw mode and get every character from the file. + /// + /// When this is set to 2 it returns comments and whitespace. When set to 1 + /// it returns comments, when it is set to 0 it returns normal tokens only. + unsigned char ExtendedTokenMode; + + //===--------------------------------------------------------------------===// + // Context that changes as the file is lexed. + // NOTE: any state that mutates when in raw mode must have save/restore code + // in Lexer::isNextPPTokenLParen. + + // BufferPtr - Current pointer into the buffer. This is the next character + // to be lexed. + const char *BufferPtr; + + // IsAtStartOfLine - True if the next lexed token should get the "start of + // line" flag set on it. + bool IsAtStartOfLine; + + bool IsAtPhysicalStartOfLine; + + bool HasLeadingSpace; + + bool HasLeadingEmptyMacro; + + // CurrentConflictMarkerState - The kind of conflict marker we are handling. + ConflictMarkerKind CurrentConflictMarkerState; + + void InitLexer(const char *BufStart, const char *BufPtr, const char *BufEnd); + +public: + /// 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(FileID FID, const llvm::MemoryBuffer *InputFile, Preprocessor &PP); + + /// 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(SourceLocation FileLoc, const LangOptions &LangOpts, + const char *BufStart, const char *BufPtr, const char *BufEnd); + + /// 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(FileID FID, const llvm::MemoryBuffer *FromFile, + const SourceManager &SM, const LangOptions &LangOpts); + + Lexer(const Lexer &) = delete; + Lexer &operator=(const Lexer &) = delete; + + /// 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. + static Lexer *Create_PragmaLexer(SourceLocation SpellingLoc, + SourceLocation ExpansionLocStart, + SourceLocation ExpansionLocEnd, + unsigned TokLen, Preprocessor &PP); + + /// getLangOpts - Return the language features currently enabled. + /// NOTE: this lexer modifies features as a file is parsed! + const LangOptions &getLangOpts() const { return LangOpts; } + + /// getFileLoc - Return the File Location for the file we are lexing out of. + /// The physical location encodes the location where the characters come from, + /// the virtual location encodes where we should *claim* the characters came + /// from. Currently this is only used by _Pragma handling. + SourceLocation getFileLoc() const { return FileLoc; } + +private: + /// Lex - Return the next token in the file. If this is the end of file, it + /// return the tok::eof token. This implicitly involves the preprocessor. + bool Lex(Token &Result); + +public: + /// isPragmaLexer - Returns true if this Lexer is being used to lex a pragma. + bool isPragmaLexer() const { return Is_PragmaLexer; } + +private: + /// IndirectLex - An indirect call to 'Lex' that can be invoked via + /// the PreprocessorLexer interface. + void IndirectLex(Token &Result) override { Lex(Result); } + +public: + /// LexFromRawLexer - Lex a token from a designated raw lexer (one with no + /// associated preprocessor object. Return true if the 'next character to + /// read' pointer points at the end of the lexer buffer, false otherwise. + bool LexFromRawLexer(Token &Result) { + assert(LexingRawMode && "Not already in raw mode!"); + Lex(Result); + // Note that lexing to the end of the buffer doesn't implicitly delete the + // lexer when in raw mode. + return BufferPtr == BufferEnd; + } + + /// isKeepWhitespaceMode - Return true if the lexer should return tokens for + /// every character in the file, including whitespace and comments. This + /// should only be used in raw mode, as the preprocessor is not prepared to + /// deal with the excess tokens. + bool isKeepWhitespaceMode() const { + return ExtendedTokenMode > 1; + } + + /// SetKeepWhitespaceMode - This method lets clients enable or disable + /// whitespace retention mode. + void SetKeepWhitespaceMode(bool Val) { + assert((!Val || LexingRawMode || LangOpts.TraditionalCPP) && + "Can only retain whitespace in raw mode or -traditional-cpp"); + ExtendedTokenMode = Val ? 2 : 0; + } + + /// inKeepCommentMode - Return true if the lexer should return comments as + /// tokens. + bool inKeepCommentMode() const { + return ExtendedTokenMode > 0; + } + + /// SetCommentRetentionMode - Change the comment retention mode of the lexer + /// to the specified mode. This is really only useful when lexing in raw + /// mode, because otherwise the lexer needs to manage this. + void SetCommentRetentionState(bool Mode) { + assert(!isKeepWhitespaceMode() && + "Can't play with comment retention state when retaining whitespace"); + ExtendedTokenMode = Mode ? 1 : 0; + } + + /// Sets the extended token mode back to its initial value, according to the + /// language options and preprocessor. This controls whether the lexer + /// produces comment and whitespace tokens. + /// + /// This requires the lexer to have an associated preprocessor. A standalone + /// lexer has nothing to reset to. + void resetExtendedTokenMode(); + + /// Gets source code buffer. + StringRef getBuffer() const { + return StringRef(BufferStart, BufferEnd - BufferStart); + } + + /// ReadToEndOfLine - Read the rest of the current preprocessor line as an + /// uninterpreted string. This switches the lexer out of directive mode. + void ReadToEndOfLine(SmallVectorImpl<char> *Result = nullptr); + + + /// Diag - Forwarding function for diagnostics. This translate a source + /// position in the current buffer into a SourceLocation object for rendering. + DiagnosticBuilder Diag(const char *Loc, unsigned DiagID) const; + + /// getSourceLocation - Return a source location identifier for the specified + /// offset in the current file. + SourceLocation getSourceLocation(const char *Loc, unsigned TokLen = 1) const; + + /// getSourceLocation - Return a source location for the next character in + /// the current file. + SourceLocation getSourceLocation() override { + return getSourceLocation(BufferPtr); + } + + /// Return the current location in the buffer. + const char *getBufferLocation() const { return BufferPtr; } + + /// Stringify - Convert the specified string into a C string by i) escaping + /// '\\' and " characters and ii) replacing newline character(s) with "\\n". + /// If Charify is true, this escapes the ' character instead of ". + static std::string Stringify(StringRef Str, bool Charify = false); + + /// Stringify - Convert the specified string into a C string by i) escaping + /// '\\' and " characters and ii) replacing newline character(s) with "\\n". + static void Stringify(SmallVectorImpl<char> &Str); + + /// 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 length of the actual result 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. + static unsigned getSpelling(const Token &Tok, const char *&Buffer, + const SourceManager &SourceMgr, + const LangOptions &LangOpts, + bool *Invalid = nullptr); + + /// getSpelling() - Return the 'spelling' of the Tok token. The spelling of a + /// token is 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. + static std::string getSpelling(const Token &Tok, + const SourceManager &SourceMgr, + const LangOptions &LangOpts, + bool *Invalid = nullptr); + + /// getSpelling - This method is used to get the spelling of the + /// token at the given source location. If, as is usually true, it + /// is not necessary to copy any data, then the returned string may + /// not point into the provided buffer. + /// + /// This method lexes at the expansion depth of the given + /// location and does not jump to the expansion or spelling + /// location. + static StringRef getSpelling(SourceLocation loc, + SmallVectorImpl<char> &buffer, + const SourceManager &SM, + const LangOptions &options, + bool *invalid = nullptr); + + /// 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. + static unsigned MeasureTokenLength(SourceLocation Loc, + const SourceManager &SM, + const LangOptions &LangOpts); + + /// Relex the token at the specified location. + /// \returns true if there was a failure, false on success. + static bool getRawToken(SourceLocation Loc, Token &Result, + const SourceManager &SM, + const LangOptions &LangOpts, + bool IgnoreWhiteSpace = false); + + /// Given a location any where in a source buffer, find the location + /// that corresponds to the beginning of the token in which the original + /// source location lands. + static SourceLocation GetBeginningOfToken(SourceLocation Loc, + const SourceManager &SM, + const LangOptions &LangOpts); + + /// Get the physical length (including trigraphs and escaped newlines) of the + /// first \p Characters characters of the token starting at TokStart. + static unsigned getTokenPrefixLength(SourceLocation TokStart, + unsigned CharNo, + const SourceManager &SM, + const LangOptions &LangOpts); + + /// AdvanceToTokenCharacter - If the current SourceLocation specifies a + /// location at the start of a token, return a new location that specifies a + /// character within the token. This handles trigraphs and escaped newlines. + static SourceLocation AdvanceToTokenCharacter(SourceLocation TokStart, + unsigned Characters, + const SourceManager &SM, + const LangOptions &LangOpts) { + return TokStart.getLocWithOffset( + getTokenPrefixLength(TokStart, Characters, SM, LangOpts)); + } + + /// 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. + static SourceLocation getLocForEndOfToken(SourceLocation Loc, unsigned Offset, + const SourceManager &SM, + const LangOptions &LangOpts); + + /// Given a token range, produce a corresponding CharSourceRange that + /// is not a token range. This allows the source range to be used by + /// components that don't have access to the lexer and thus can't find the + /// end of the range for themselves. + static CharSourceRange getAsCharRange(SourceRange Range, + const SourceManager &SM, + const LangOptions &LangOpts) { + SourceLocation End = getLocForEndOfToken(Range.getEnd(), 0, SM, LangOpts); + return End.isInvalid() ? CharSourceRange() + : CharSourceRange::getCharRange( + Range.getBegin(), End.getLocWithOffset(-1)); + } + static CharSourceRange getAsCharRange(CharSourceRange Range, + const SourceManager &SM, + const LangOptions &LangOpts) { + return Range.isTokenRange() + ? getAsCharRange(Range.getAsRange(), SM, LangOpts) + : Range; + } + + /// Returns true if the given MacroID location points at the first + /// token of the macro expansion. + /// + /// \param MacroBegin If non-null and function returns true, it is set to + /// begin location of the macro. + static bool isAtStartOfMacroExpansion(SourceLocation loc, + const SourceManager &SM, + const LangOptions &LangOpts, + SourceLocation *MacroBegin = nullptr); + + /// Returns true if the given MacroID location points at the last + /// token of the macro expansion. + /// + /// \param MacroEnd If non-null and function returns true, it is set to + /// end location of the macro. + static bool isAtEndOfMacroExpansion(SourceLocation loc, + const SourceManager &SM, + const LangOptions &LangOpts, + SourceLocation *MacroEnd = nullptr); + + /// Accepts a range and returns a character range with file locations. + /// + /// Returns a null range if a part of the range resides inside a macro + /// expansion or the range does not reside on the same FileID. + /// + /// This function is trying to deal with macros and return a range based on + /// file locations. The cases where it can successfully handle macros are: + /// + /// -begin or end range lies at the start or end of a macro expansion, in + /// which case the location will be set to the expansion point, e.g: + /// \#define M 1 2 + /// a M + /// If you have a range [a, 2] (where 2 came from the macro), the function + /// will return a range for "a M" + /// if you have range [a, 1], the function will fail because the range + /// overlaps with only a part of the macro + /// + /// -The macro is a function macro and the range can be mapped to the macro + /// arguments, e.g: + /// \#define M 1 2 + /// \#define FM(x) x + /// FM(a b M) + /// if you have range [b, 2], the function will return the file range "b M" + /// inside the macro arguments. + /// if you have range [a, 2], the function will return the file range + /// "FM(a b M)" since the range includes all of the macro expansion. + static CharSourceRange makeFileCharRange(CharSourceRange Range, + const SourceManager &SM, + const LangOptions &LangOpts); + + /// Returns a string for the source that the range encompasses. + static StringRef getSourceText(CharSourceRange Range, + const SourceManager &SM, + const LangOptions &LangOpts, + bool *Invalid = nullptr); + + /// Retrieve the name of the immediate macro expansion. + /// + /// This routine starts from a source location, and finds the name of the macro + /// responsible for its immediate expansion. It looks through any intervening + /// macro argument expansions to compute this. It returns a StringRef which + /// refers to the SourceManager-owned buffer of the source where that macro + /// name is spelled. Thus, the result shouldn't out-live that SourceManager. + static StringRef getImmediateMacroName(SourceLocation Loc, + const SourceManager &SM, + const LangOptions &LangOpts); + + /// Retrieve the name of the immediate macro expansion. + /// + /// This routine starts from a source location, and finds the name of the + /// macro responsible for its immediate expansion. It looks through any + /// intervening macro argument expansions to compute this. It returns a + /// StringRef which refers to the SourceManager-owned buffer of the source + /// where that macro name is spelled. Thus, the result shouldn't out-live + /// that SourceManager. + /// + /// This differs from Lexer::getImmediateMacroName in that any macro argument + /// location will result in the topmost function macro that accepted it. + /// e.g. + /// \code + /// MAC1( MAC2(foo) ) + /// \endcode + /// for location of 'foo' token, this function will return "MAC1" while + /// Lexer::getImmediateMacroName will return "MAC2". + static StringRef getImmediateMacroNameForDiagnostics( + SourceLocation Loc, const SourceManager &SM, const LangOptions &LangOpts); + + /// Compute the preamble of the given file. + /// + /// The preamble of a file contains the initial comments, include directives, + /// and other preprocessor directives that occur before the code in this + /// particular file actually begins. The preamble of the main source file is + /// a potential prefix header. + /// + /// \param Buffer The memory buffer containing the file's contents. + /// + /// \param MaxLines If non-zero, restrict the length of the preamble + /// to fewer than this number of lines. + /// + /// \returns The offset into the file where the preamble ends and the rest + /// of the file begins along with a boolean value indicating whether + /// the preamble ends at the beginning of a new line. + static PreambleBounds ComputePreamble(StringRef Buffer, + const LangOptions &LangOpts, + unsigned MaxLines = 0); + + /// Finds the token that comes right after the given location. + /// + /// Returns the next token, or none if the location is inside a macro. + static Optional<Token> findNextToken(SourceLocation Loc, + const SourceManager &SM, + const LangOptions &LangOpts); + + /// 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. + static SourceLocation findLocationAfterToken(SourceLocation loc, + tok::TokenKind TKind, + const SourceManager &SM, + const LangOptions &LangOpts, + bool SkipTrailingWhitespaceAndNewLine); + + /// Returns true if the given character could appear in an identifier. + static bool isIdentifierBodyChar(char c, const LangOptions &LangOpts); + + /// Checks whether new line pointed by Str is preceded by escape + /// sequence. + static bool isNewLineEscaped(const char *BufferStart, const char *Str); + + /// getCharAndSizeNoWarn - Like the getCharAndSize method, but does not ever + /// emit a warning. + static inline char getCharAndSizeNoWarn(const char *Ptr, unsigned &Size, + const LangOptions &LangOpts) { + // If this is not a trigraph and not a UCN or escaped newline, return + // quickly. + if (isObviouslySimpleCharacter(Ptr[0])) { + Size = 1; + return *Ptr; + } + + Size = 0; + return getCharAndSizeSlowNoWarn(Ptr, Size, LangOpts); + } + + /// Returns the leading whitespace for line that corresponds to the given + /// location \p Loc. + static StringRef getIndentationForLine(SourceLocation Loc, + const SourceManager &SM); + +private: + //===--------------------------------------------------------------------===// + // Internal implementation interfaces. + + /// LexTokenInternal - Internal interface to lex a preprocessing token. Called + /// by Lex. + /// + bool LexTokenInternal(Token &Result, bool TokAtPhysicalStartOfLine); + + bool CheckUnicodeWhitespace(Token &Result, uint32_t C, const char *CurPtr); + + /// Given that a token begins with the Unicode character \p C, figure out + /// what kind of token it is and dispatch to the appropriate lexing helper + /// function. + bool LexUnicode(Token &Result, uint32_t C, const char *CurPtr); + + /// FormTokenWithChars - When we lex a token, we have identified a span + /// starting at BufferPtr, going to TokEnd that forms the token. This method + /// takes that range and assigns it to the token as its location and size. In + /// addition, since tokens cannot overlap, this also updates BufferPtr to be + /// TokEnd. + void FormTokenWithChars(Token &Result, const char *TokEnd, + tok::TokenKind Kind) { + unsigned TokLen = TokEnd-BufferPtr; + Result.setLength(TokLen); + Result.setLocation(getSourceLocation(BufferPtr, TokLen)); + Result.setKind(Kind); + BufferPtr = TokEnd; + } + + /// isNextPPTokenLParen - Return 1 if the next unexpanded token 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 this lexer. + unsigned isNextPPTokenLParen(); + + //===--------------------------------------------------------------------===// + // Lexer character reading interfaces. + + // This lexer is built on two interfaces for reading characters, both of which + // automatically provide phase 1/2 translation. getAndAdvanceChar is used + // when we know that we will be reading a character from the input buffer and + // that this character will be part of the result token. This occurs in (f.e.) + // string processing, because we know we need to read until we find the + // closing '"' character. + // + // The second interface is the combination of getCharAndSize with + // ConsumeChar. getCharAndSize reads a phase 1/2 translated character, + // returning it and its size. If the lexer decides that this character is + // part of the current token, it calls ConsumeChar on it. This two stage + // approach allows us to emit diagnostics for characters (e.g. warnings about + // trigraphs), knowing that they only are emitted if the character is + // consumed. + + /// isObviouslySimpleCharacter - Return true if the specified character is + /// obviously the same in translation phase 1 and translation phase 3. This + /// can return false for characters that end up being the same, but it will + /// never return true for something that needs to be mapped. + static bool isObviouslySimpleCharacter(char C) { + return C != '?' && C != '\\'; + } + + /// getAndAdvanceChar - Read a single 'character' from the specified buffer, + /// advance over it, and return it. This is tricky in several cases. Here we + /// just handle the trivial case and fall-back to the non-inlined + /// getCharAndSizeSlow method to handle the hard case. + inline char getAndAdvanceChar(const char *&Ptr, Token &Tok) { + // If this is not a trigraph and not a UCN or escaped newline, return + // quickly. + if (isObviouslySimpleCharacter(Ptr[0])) return *Ptr++; + + unsigned Size = 0; + char C = getCharAndSizeSlow(Ptr, Size, &Tok); + Ptr += Size; + return C; + } + + /// ConsumeChar - When a character (identified by getCharAndSize) is consumed + /// and added to a given token, check to see if there are diagnostics that + /// need to be emitted or flags that need to be set on the token. If so, do + /// it. + const char *ConsumeChar(const char *Ptr, unsigned Size, Token &Tok) { + // Normal case, we consumed exactly one token. Just return it. + if (Size == 1) + return Ptr+Size; + + // Otherwise, re-lex the character with a current token, allowing + // diagnostics to be emitted and flags to be set. + Size = 0; + getCharAndSizeSlow(Ptr, Size, &Tok); + return Ptr+Size; + } + + /// getCharAndSize - Peek a single 'character' from the specified buffer, + /// get its size, and return it. This is tricky in several cases. Here we + /// just handle the trivial case and fall-back to the non-inlined + /// getCharAndSizeSlow method to handle the hard case. + inline char getCharAndSize(const char *Ptr, unsigned &Size) { + // If this is not a trigraph and not a UCN or escaped newline, return + // quickly. + if (isObviouslySimpleCharacter(Ptr[0])) { + Size = 1; + return *Ptr; + } + + Size = 0; + return getCharAndSizeSlow(Ptr, Size); + } + + /// getCharAndSizeSlow - Handle the slow/uncommon case of the getCharAndSize + /// method. + char getCharAndSizeSlow(const char *Ptr, unsigned &Size, + Token *Tok = nullptr); + + /// 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 "\" on entry + /// to this function. + static unsigned getEscapedNewLineSize(const char *P); + + /// 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. + static const char *SkipEscapedNewLines(const char *P); + + /// getCharAndSizeSlowNoWarn - Same as getCharAndSizeSlow, but never emits a + /// diagnostic. + static char getCharAndSizeSlowNoWarn(const char *Ptr, unsigned &Size, + const LangOptions &LangOpts); + + //===--------------------------------------------------------------------===// + // Other lexer functions. + + void SetByteOffset(unsigned Offset, bool StartOfLine); + + void PropagateLineStartLeadingSpaceInfo(Token &Result); + + const char *LexUDSuffix(Token &Result, const char *CurPtr, + bool IsStringLiteral); + + // Helper functions to lex the remainder of a token of the specific type. + bool LexIdentifier (Token &Result, const char *CurPtr); + bool LexNumericConstant (Token &Result, const char *CurPtr); + bool LexStringLiteral (Token &Result, const char *CurPtr, + tok::TokenKind Kind); + bool LexRawStringLiteral (Token &Result, const char *CurPtr, + tok::TokenKind Kind); + bool LexAngledStringLiteral(Token &Result, const char *CurPtr); + bool LexCharConstant (Token &Result, const char *CurPtr, + tok::TokenKind Kind); + bool LexEndOfFile (Token &Result, const char *CurPtr); + bool SkipWhitespace (Token &Result, const char *CurPtr, + bool &TokAtPhysicalStartOfLine); + bool SkipLineComment (Token &Result, const char *CurPtr, + bool &TokAtPhysicalStartOfLine); + bool SkipBlockComment (Token &Result, const char *CurPtr, + bool &TokAtPhysicalStartOfLine); + bool SaveLineComment (Token &Result, const char *CurPtr); + + bool IsStartOfConflictMarker(const char *CurPtr); + bool HandleEndOfConflictMarker(const char *CurPtr); + + bool lexEditorPlaceholder(Token &Result, const char *CurPtr); + + bool isCodeCompletionPoint(const char *CurPtr) const; + void cutOffLexing() { BufferPtr = BufferEnd; } + + bool isHexaLiteral(const char *Start, const LangOptions &LangOpts); + + void codeCompleteIncludedFile(const char *PathStart, + const char *CompletionPoint, bool IsAngled); + + /// Read a universal character name. + /// + /// \param StartPtr The position in the source buffer after the initial '\'. + /// If the UCN is syntactically well-formed (but not + /// necessarily valid), this parameter will be updated to + /// point to the character after the UCN. + /// \param SlashLoc The position in the source buffer of the '\'. + /// \param Result The token being formed. Pass \c nullptr to suppress + /// diagnostics and handle token formation in the caller. + /// + /// \return The Unicode codepoint specified by the UCN, or 0 if the UCN is + /// invalid. + uint32_t tryReadUCN(const char *&StartPtr, const char *SlashLoc, Token *Result); + + /// Try to consume a UCN as part of an identifier at the current + /// location. + /// \param CurPtr Initially points to the range of characters in the source + /// buffer containing the '\'. Updated to point past the end of + /// the UCN on success. + /// \param Size The number of characters occupied by the '\' (including + /// trigraphs and escaped newlines). + /// \param Result The token being produced. Marked as containing a UCN on + /// success. + /// \return \c true if a UCN was lexed and it produced an acceptable + /// identifier character, \c false otherwise. + bool tryConsumeIdentifierUCN(const char *&CurPtr, unsigned Size, + Token &Result); + + /// Try to consume an identifier character encoded in UTF-8. + /// \param CurPtr Points to the start of the (potential) UTF-8 code unit + /// sequence. On success, updated to point past the end of it. + /// \return \c true if a UTF-8 sequence mapping to an acceptable identifier + /// character was lexed, \c false otherwise. + bool tryConsumeIdentifierUTF8Char(const char *&CurPtr); +}; + +} // namespace clang + +#endif // LLVM_CLANG_LEX_LEXER_H |