Coverage Report

Created: 2020-02-15 09:57

/Users/buildslave/jenkins/workspace/coverage/llvm-project/clang/include/clang/Lex/Lexer.h
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Count
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//===- Lexer.h - C Language Family Lexer ------------------------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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//  This file defines the Lexer interface.
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_CLANG_LEX_LEXER_H
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#define LLVM_CLANG_LEX_LEXER_H
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#include "clang/Basic/LangOptions.h"
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#include "clang/Basic/SourceLocation.h"
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#include "clang/Basic/TokenKinds.h"
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#include "clang/Lex/PreprocessorLexer.h"
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#include "clang/Lex/Token.h"
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#include "llvm/ADT/Optional.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/ADT/StringRef.h"
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#include <cassert>
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#include <cstdint>
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#include <string>
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namespace llvm {
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class MemoryBuffer;
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} // namespace llvm
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namespace clang {
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class DiagnosticBuilder;
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class Preprocessor;
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class SourceManager;
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/// ConflictMarkerKind - Kinds of conflict marker which the lexer might be
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/// recovering from.
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enum ConflictMarkerKind {
43
  /// Not within a conflict marker.
44
  CMK_None,
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46
  /// A normal or diff3 conflict marker, initiated by at least 7 "<"s,
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  /// separated by at least 7 "="s or "|"s, and terminated by at least 7 ">"s.
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  CMK_Normal,
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50
  /// A Perforce-style conflict marker, initiated by 4 ">"s,
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  /// separated by 4 "="s, and terminated by 4 "<"s.
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  CMK_Perforce
53
};
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/// Describes the bounds (start, size) of the preamble and a flag required by
56
/// PreprocessorOptions::PrecompiledPreambleBytes.
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/// The preamble includes the BOM, if any.
58
struct PreambleBounds {
59
  /// Size of the preamble in bytes.
60
  unsigned Size;
61
62
  /// Whether the preamble ends at the start of a new line.
63
  ///
64
  /// Used to inform the lexer as to whether it's starting at the beginning of
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  /// a line after skipping the preamble.
66
  bool PreambleEndsAtStartOfLine;
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68
  PreambleBounds(unsigned Size, bool PreambleEndsAtStartOfLine)
69
1.36k
      : Size(Size), PreambleEndsAtStartOfLine(PreambleEndsAtStartOfLine) {}
70
};
71
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/// Lexer - This provides a simple interface that turns a text buffer into a
73
/// stream of tokens.  This provides no support for file reading or buffering,
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/// or buffering/seeking of tokens, only forward lexing is supported.  It relies
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/// on the specified Preprocessor object to handle preprocessor directives, etc.
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class Lexer : public PreprocessorLexer {
77
  friend class Preprocessor;
78
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  void anchor() override;
80
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  //===--------------------------------------------------------------------===//
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  // Constant configuration values for this lexer.
83
84
  // Start of the buffer.
85
  const char *BufferStart;
86
87
  // End of the buffer.
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  const char *BufferEnd;
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  // Location for start of file.
91
  SourceLocation FileLoc;
92
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  // LangOpts enabled by this language (cache).
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  LangOptions LangOpts;
95
96
  // True if lexer for _Pragma handling.
97
  bool Is_PragmaLexer;
98
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  //===--------------------------------------------------------------------===//
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  // Context-specific lexing flags set by the preprocessor.
101
  //
102
103
  /// ExtendedTokenMode - The lexer can optionally keep comments and whitespace
104
  /// and return them as tokens.  This is used for -C and -CC modes, and
105
  /// whitespace preservation can be useful for some clients that want to lex
106
  /// the file in raw mode and get every character from the file.
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  ///
108
  /// When this is set to 2 it returns comments and whitespace.  When set to 1
109
  /// it returns comments, when it is set to 0 it returns normal tokens only.
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  unsigned char ExtendedTokenMode;
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112
  //===--------------------------------------------------------------------===//
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  // Context that changes as the file is lexed.
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  // NOTE: any state that mutates when in raw mode must have save/restore code
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  // in Lexer::isNextPPTokenLParen.
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  // BufferPtr - Current pointer into the buffer.  This is the next character
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  // to be lexed.
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  const char *BufferPtr;
120
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  // IsAtStartOfLine - True if the next lexed token should get the "start of
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  // line" flag set on it.
123
  bool IsAtStartOfLine;
124
125
  bool IsAtPhysicalStartOfLine;
126
127
  bool HasLeadingSpace;
128
129
  bool HasLeadingEmptyMacro;
130
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  // CurrentConflictMarkerState - The kind of conflict marker we are handling.
132
  ConflictMarkerKind CurrentConflictMarkerState;
133
134
  void InitLexer(const char *BufStart, const char *BufPtr, const char *BufEnd);
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public:
137
  /// Lexer constructor - Create a new lexer object for the specified buffer
138
  /// with the specified preprocessor managing the lexing process.  This lexer
139
  /// assumes that the associated file buffer and Preprocessor objects will
140
  /// outlive it, so it doesn't take ownership of either of them.
141
  Lexer(FileID FID, const llvm::MemoryBuffer *InputFile, Preprocessor &PP);
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  /// Lexer constructor - Create a new raw lexer object.  This object is only
144
  /// suitable for calls to 'LexFromRawLexer'.  This lexer assumes that the
145
  /// text range will outlive it, so it doesn't take ownership of it.
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  Lexer(SourceLocation FileLoc, const LangOptions &LangOpts,
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        const char *BufStart, const char *BufPtr, const char *BufEnd);
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  /// Lexer constructor - Create a new raw lexer object.  This object is only
150
  /// suitable for calls to 'LexFromRawLexer'.  This lexer assumes that the
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  /// text range will outlive it, so it doesn't take ownership of it.
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  Lexer(FileID FID, const llvm::MemoryBuffer *FromFile,
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        const SourceManager &SM, const LangOptions &LangOpts);
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  Lexer(const Lexer &) = delete;
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  Lexer &operator=(const Lexer &) = delete;
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  /// Create_PragmaLexer: Lexer constructor - Create a new lexer object for
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  /// _Pragma expansion.  This has a variety of magic semantics that this method
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  /// sets up.  It returns a new'd Lexer that must be delete'd when done.
161
  static Lexer *Create_PragmaLexer(SourceLocation SpellingLoc,
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                                   SourceLocation ExpansionLocStart,
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                                   SourceLocation ExpansionLocEnd,
164
                                   unsigned TokLen, Preprocessor &PP);
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166
  /// getLangOpts - Return the language features currently enabled.
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  /// NOTE: this lexer modifies features as a file is parsed!
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16.8M
  const LangOptions &getLangOpts() const { return LangOpts; }
169
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  /// getFileLoc - Return the File Location for the file we are lexing out of.
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  /// The physical location encodes the location where the characters come from,
172
  /// the virtual location encodes where we should *claim* the characters came
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  /// from.  Currently this is only used by _Pragma handling.
174
1.91M
  SourceLocation getFileLoc() const { return FileLoc; }
175
176
private:
177
  /// Lex - Return the next token in the file.  If this is the end of file, it
178
  /// return the tok::eof token.  This implicitly involves the preprocessor.
179
  bool Lex(Token &Result);
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181
public:
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  /// isPragmaLexer - Returns true if this Lexer is being used to lex a pragma.
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3.91M
  bool isPragmaLexer() const { return Is_PragmaLexer; }
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185
private:
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  /// IndirectLex - An indirect call to 'Lex' that can be invoked via
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  ///  the PreprocessorLexer interface.
188
0
  void IndirectLex(Token &Result) override { Lex(Result); }
189
190
public:
191
  /// LexFromRawLexer - Lex a token from a designated raw lexer (one with no
192
  /// associated preprocessor object.  Return true if the 'next character to
193
  /// read' pointer points at the end of the lexer buffer, false otherwise.
194
42.8M
  bool LexFromRawLexer(Token &Result) {
195
42.8M
    assert(LexingRawMode && "Not already in raw mode!");
196
42.8M
    Lex(Result);
197
42.8M
    // Note that lexing to the end of the buffer doesn't implicitly delete the
198
42.8M
    // lexer when in raw mode.
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42.8M
    return BufferPtr == BufferEnd;
200
42.8M
  }
201
202
  /// isKeepWhitespaceMode - Return true if the lexer should return tokens for
203
  /// every character in the file, including whitespace and comments.  This
204
  /// should only be used in raw mode, as the preprocessor is not prepared to
205
  /// deal with the excess tokens.
206
1.17G
  bool isKeepWhitespaceMode() const {
207
1.17G
    return ExtendedTokenMode > 1;
208
1.17G
  }
209
210
  /// SetKeepWhitespaceMode - This method lets clients enable or disable
211
  /// whitespace retention mode.
212
185M
  void SetKeepWhitespaceMode(bool Val) {
213
185M
    assert((!Val || LexingRawMode || LangOpts.TraditionalCPP) &&
214
185M
           "Can only retain whitespace in raw mode or -traditional-cpp");
215
185M
    ExtendedTokenMode = Val ? 
248.0k
:
0185M
;
216
185M
  }
217
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  /// inKeepCommentMode - Return true if the lexer should return comments as
219
  /// tokens.
220
78.8M
  bool inKeepCommentMode() const {
221
78.8M
    return ExtendedTokenMode > 0;
222
78.8M
  }
223
224
  /// SetCommentRetentionMode - Change the comment retention mode of the lexer
225
  /// to the specified mode.  This is really only useful when lexing in raw
226
  /// mode, because otherwise the lexer needs to manage this.
227
265M
  void SetCommentRetentionState(bool Mode) {
228
265M
    assert(!isKeepWhitespaceMode() &&
229
265M
           "Can't play with comment retention state when retaining whitespace");
230
265M
    ExtendedTokenMode = Mode ? 
129.2M
:
0236M
;
231
265M
  }
232
233
  /// Sets the extended token mode back to its initial value, according to the
234
  /// language options and preprocessor. This controls whether the lexer
235
  /// produces comment and whitespace tokens.
236
  ///
237
  /// This requires the lexer to have an associated preprocessor. A standalone
238
  /// lexer has nothing to reset to.
239
  void resetExtendedTokenMode();
240
241
  /// Gets source code buffer.
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5.19k
  StringRef getBuffer() const {
243
5.19k
    return StringRef(BufferStart, BufferEnd - BufferStart);
244
5.19k
  }
245
246
  /// ReadToEndOfLine - Read the rest of the current preprocessor line as an
247
  /// uninterpreted string.  This switches the lexer out of directive mode.
248
  void ReadToEndOfLine(SmallVectorImpl<char> *Result = nullptr);
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250
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  /// Diag - Forwarding function for diagnostics.  This translate a source
252
  /// position in the current buffer into a SourceLocation object for rendering.
253
  DiagnosticBuilder Diag(const char *Loc, unsigned DiagID) const;
254
255
  /// getSourceLocation - Return a source location identifier for the specified
256
  /// offset in the current file.
257
  SourceLocation getSourceLocation(const char *Loc, unsigned TokLen = 1) const;
258
259
  /// getSourceLocation - Return a source location for the next character in
260
  /// the current file.
261
6.35M
  SourceLocation getSourceLocation() override {
262
6.35M
    return getSourceLocation(BufferPtr);
263
6.35M
  }
264
265
  /// Return the current location in the buffer.
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48.2k
  const char *getBufferLocation() const { return BufferPtr; }
267
268
  /// Returns the current lexing offset.
269
20
  unsigned getCurrentBufferOffset() {
270
20
    assert(BufferPtr >= BufferStart && "Invalid buffer state");
271
20
    return BufferPtr - BufferStart;
272
20
  }
273
274
  /// Skip over \p NumBytes bytes.
275
  ///
276
  /// If the skip is successful, the next token will be lexed from the new
277
  /// offset. The lexer also assumes that we skipped to the start of the line.
278
  ///
279
  /// \returns true if the skip failed (new offset would have been past the
280
  /// end of the buffer), false otherwise.
281
  bool skipOver(unsigned NumBytes);
282
283
  /// Stringify - Convert the specified string into a C string by i) escaping
284
  /// '\\' and " characters and ii) replacing newline character(s) with "\\n".
285
  /// If Charify is true, this escapes the ' character instead of ".
286
  static std::string Stringify(StringRef Str, bool Charify = false);
287
288
  /// Stringify - Convert the specified string into a C string by i) escaping
289
  /// '\\' and " characters and ii) replacing newline character(s) with "\\n".
290
  static void Stringify(SmallVectorImpl<char> &Str);
291
292
  /// getSpelling - This method is used to get the spelling of a token into a
293
  /// preallocated buffer, instead of as an std::string.  The caller is required
294
  /// to allocate enough space for the token, which is guaranteed to be at least
295
  /// Tok.getLength() bytes long.  The length of the actual result is returned.
296
  ///
297
  /// Note that this method may do two possible things: it may either fill in
298
  /// the buffer specified with characters, or it may *change the input pointer*
299
  /// to point to a constant buffer with the data already in it (avoiding a
300
  /// copy).  The caller is not allowed to modify the returned buffer pointer
301
  /// if an internal buffer is returned.
302
  static unsigned getSpelling(const Token &Tok, const char *&Buffer,
303
                              const SourceManager &SourceMgr,
304
                              const LangOptions &LangOpts,
305
                              bool *Invalid = nullptr);
306
307
  /// getSpelling() - Return the 'spelling' of the Tok token.  The spelling of a
308
  /// token is the characters used to represent the token in the source file
309
  /// after trigraph expansion and escaped-newline folding.  In particular, this
310
  /// wants to get the true, uncanonicalized, spelling of things like digraphs
311
  /// UCNs, etc.
312
  static std::string getSpelling(const Token &Tok,
313
                                 const SourceManager &SourceMgr,
314
                                 const LangOptions &LangOpts,
315
                                 bool *Invalid = nullptr);
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317
  /// getSpelling - This method is used to get the spelling of the
318
  /// token at the given source location.  If, as is usually true, it
319
  /// is not necessary to copy any data, then the returned string may
320
  /// not point into the provided buffer.
321
  ///
322
  /// This method lexes at the expansion depth of the given
323
  /// location and does not jump to the expansion or spelling
324
  /// location.
325
  static StringRef getSpelling(SourceLocation loc,
326
                               SmallVectorImpl<char> &buffer,
327
                               const SourceManager &SM,
328
                               const LangOptions &options,
329
                               bool *invalid = nullptr);
330
331
  /// MeasureTokenLength - Relex the token at the specified location and return
332
  /// its length in bytes in the input file.  If the token needs cleaning (e.g.
333
  /// includes a trigraph or an escaped newline) then this count includes bytes
334
  /// that are part of that.
335
  static unsigned MeasureTokenLength(SourceLocation Loc,
336
                                     const SourceManager &SM,
337
                                     const LangOptions &LangOpts);
338
339
  /// Relex the token at the specified location.
340
  /// \returns true if there was a failure, false on success.
341
  static bool getRawToken(SourceLocation Loc, Token &Result,
342
                          const SourceManager &SM,
343
                          const LangOptions &LangOpts,
344
                          bool IgnoreWhiteSpace = false);
345
346
  /// Given a location any where in a source buffer, find the location
347
  /// that corresponds to the beginning of the token in which the original
348
  /// source location lands.
349
  static SourceLocation GetBeginningOfToken(SourceLocation Loc,
350
                                            const SourceManager &SM,
351
                                            const LangOptions &LangOpts);
352
353
  /// Get the physical length (including trigraphs and escaped newlines) of the
354
  /// first \p Characters characters of the token starting at TokStart.
355
  static unsigned getTokenPrefixLength(SourceLocation TokStart,
356
                                       unsigned CharNo,
357
                                       const SourceManager &SM,
358
                                       const LangOptions &LangOpts);
359
360
  /// AdvanceToTokenCharacter - If the current SourceLocation specifies a
361
  /// location at the start of a token, return a new location that specifies a
362
  /// character within the token.  This handles trigraphs and escaped newlines.
363
  static SourceLocation AdvanceToTokenCharacter(SourceLocation TokStart,
364
                                                unsigned Characters,
365
                                                const SourceManager &SM,
366
45.8k
                                                const LangOptions &LangOpts) {
367
45.8k
    return TokStart.getLocWithOffset(
368
45.8k
        getTokenPrefixLength(TokStart, Characters, SM, LangOpts));
369
45.8k
  }
370
371
  /// Computes the source location just past the end of the
372
  /// token at this source location.
373
  ///
374
  /// This routine can be used to produce a source location that
375
  /// points just past the end of the token referenced by \p Loc, and
376
  /// is generally used when a diagnostic needs to point just after a
377
  /// token where it expected something different that it received. If
378
  /// the returned source location would not be meaningful (e.g., if
379
  /// it points into a macro), this routine returns an invalid
380
  /// source location.
381
  ///
382
  /// \param Offset an offset from the end of the token, where the source
383
  /// location should refer to. The default offset (0) produces a source
384
  /// location pointing just past the end of the token; an offset of 1 produces
385
  /// a source location pointing to the last character in the token, etc.
386
  static SourceLocation getLocForEndOfToken(SourceLocation Loc, unsigned Offset,
387
                                            const SourceManager &SM,
388
                                            const LangOptions &LangOpts);
389
390
  /// Given a token range, produce a corresponding CharSourceRange that
391
  /// is not a token range. This allows the source range to be used by
392
  /// components that don't have access to the lexer and thus can't find the
393
  /// end of the range for themselves.
394
  static CharSourceRange getAsCharRange(SourceRange Range,
395
                                        const SourceManager &SM,
396
6.15k
                                        const LangOptions &LangOpts) {
397
6.15k
    SourceLocation End = getLocForEndOfToken(Range.getEnd(), 0, SM, LangOpts);
398
6.15k
    return End.isInvalid() ? 
CharSourceRange()0
399
6.15k
                           : CharSourceRange::getCharRange(
400
6.15k
                                 Range.getBegin(), End);
401
6.15k
  }
402
  static CharSourceRange getAsCharRange(CharSourceRange Range,
403
                                        const SourceManager &SM,
404
1.85k
                                        const LangOptions &LangOpts) {
405
1.85k
    return Range.isTokenRange()
406
1.85k
               ? 
getAsCharRange(Range.getAsRange(), SM, LangOpts)1.85k
407
1.85k
               : 
Range1
;
408
1.85k
  }
409
410
  /// Returns true if the given MacroID location points at the first
411
  /// token of the macro expansion.
412
  ///
413
  /// \param MacroBegin If non-null and function returns true, it is set to
414
  /// begin location of the macro.
415
  static bool isAtStartOfMacroExpansion(SourceLocation loc,
416
                                        const SourceManager &SM,
417
                                        const LangOptions &LangOpts,
418
                                        SourceLocation *MacroBegin = nullptr);
419
420
  /// Returns true if the given MacroID location points at the last
421
  /// token of the macro expansion.
422
  ///
423
  /// \param MacroEnd If non-null and function returns true, it is set to
424
  /// end location of the macro.
425
  static bool isAtEndOfMacroExpansion(SourceLocation loc,
426
                                      const SourceManager &SM,
427
                                      const LangOptions &LangOpts,
428
                                      SourceLocation *MacroEnd = nullptr);
429
430
  /// Accepts a range and returns a character range with file locations.
431
  ///
432
  /// Returns a null range if a part of the range resides inside a macro
433
  /// expansion or the range does not reside on the same FileID.
434
  ///
435
  /// This function is trying to deal with macros and return a range based on
436
  /// file locations. The cases where it can successfully handle macros are:
437
  ///
438
  /// -begin or end range lies at the start or end of a macro expansion, in
439
  ///  which case the location will be set to the expansion point, e.g:
440
  ///    \#define M 1 2
441
  ///    a M
442
  /// If you have a range [a, 2] (where 2 came from the macro), the function
443
  /// will return a range for "a M"
444
  /// if you have range [a, 1], the function will fail because the range
445
  /// overlaps with only a part of the macro
446
  ///
447
  /// -The macro is a function macro and the range can be mapped to the macro
448
  ///  arguments, e.g:
449
  ///    \#define M 1 2
450
  ///    \#define FM(x) x
451
  ///    FM(a b M)
452
  /// if you have range [b, 2], the function will return the file range "b M"
453
  /// inside the macro arguments.
454
  /// if you have range [a, 2], the function will return the file range
455
  /// "FM(a b M)" since the range includes all of the macro expansion.
456
  static CharSourceRange makeFileCharRange(CharSourceRange Range,
457
                                           const SourceManager &SM,
458
                                           const LangOptions &LangOpts);
459
460
  /// Returns a string for the source that the range encompasses.
461
  static StringRef getSourceText(CharSourceRange Range,
462
                                 const SourceManager &SM,
463
                                 const LangOptions &LangOpts,
464
                                 bool *Invalid = nullptr);
465
466
  /// Retrieve the name of the immediate macro expansion.
467
  ///
468
  /// This routine starts from a source location, and finds the name of the macro
469
  /// responsible for its immediate expansion. It looks through any intervening
470
  /// macro argument expansions to compute this. It returns a StringRef which
471
  /// refers to the SourceManager-owned buffer of the source where that macro
472
  /// name is spelled. Thus, the result shouldn't out-live that SourceManager.
473
  static StringRef getImmediateMacroName(SourceLocation Loc,
474
                                         const SourceManager &SM,
475
                                         const LangOptions &LangOpts);
476
477
  /// Retrieve the name of the immediate macro expansion.
478
  ///
479
  /// This routine starts from a source location, and finds the name of the
480
  /// macro responsible for its immediate expansion. It looks through any
481
  /// intervening macro argument expansions to compute this. It returns a
482
  /// StringRef which refers to the SourceManager-owned buffer of the source
483
  /// where that macro name is spelled. Thus, the result shouldn't out-live
484
  /// that SourceManager.
485
  ///
486
  /// This differs from Lexer::getImmediateMacroName in that any macro argument
487
  /// location will result in the topmost function macro that accepted it.
488
  /// e.g.
489
  /// \code
490
  ///   MAC1( MAC2(foo) )
491
  /// \endcode
492
  /// for location of 'foo' token, this function will return "MAC1" while
493
  /// Lexer::getImmediateMacroName will return "MAC2".
494
  static StringRef getImmediateMacroNameForDiagnostics(
495
      SourceLocation Loc, const SourceManager &SM, const LangOptions &LangOpts);
496
497
  /// Compute the preamble of the given file.
498
  ///
499
  /// The preamble of a file contains the initial comments, include directives,
500
  /// and other preprocessor directives that occur before the code in this
501
  /// particular file actually begins. The preamble of the main source file is
502
  /// a potential prefix header.
503
  ///
504
  /// \param Buffer The memory buffer containing the file's contents.
505
  ///
506
  /// \param MaxLines If non-zero, restrict the length of the preamble
507
  /// to fewer than this number of lines.
508
  ///
509
  /// \returns The offset into the file where the preamble ends and the rest
510
  /// of the file begins along with a boolean value indicating whether
511
  /// the preamble ends at the beginning of a new line.
512
  static PreambleBounds ComputePreamble(StringRef Buffer,
513
                                        const LangOptions &LangOpts,
514
                                        unsigned MaxLines = 0);
515
516
  /// Finds the token that comes right after the given location.
517
  ///
518
  /// Returns the next token, or none if the location is inside a macro.
519
  static Optional<Token> findNextToken(SourceLocation Loc,
520
                                       const SourceManager &SM,
521
                                       const LangOptions &LangOpts);
522
523
  /// Checks that the given token is the first token that occurs after
524
  /// the given location (this excludes comments and whitespace). Returns the
525
  /// location immediately after the specified token. If the token is not found
526
  /// or the location is inside a macro, the returned source location will be
527
  /// invalid.
528
  static SourceLocation findLocationAfterToken(SourceLocation loc,
529
                                         tok::TokenKind TKind,
530
                                         const SourceManager &SM,
531
                                         const LangOptions &LangOpts,
532
                                         bool SkipTrailingWhitespaceAndNewLine);
533
534
  /// Returns true if the given character could appear in an identifier.
535
  static bool isIdentifierBodyChar(char c, const LangOptions &LangOpts);
536
537
  /// Checks whether new line pointed by Str is preceded by escape
538
  /// sequence.
539
  static bool isNewLineEscaped(const char *BufferStart, const char *Str);
540
541
  /// getCharAndSizeNoWarn - Like the getCharAndSize method, but does not ever
542
  /// emit a warning.
543
  static inline char getCharAndSizeNoWarn(const char *Ptr, unsigned &Size,
544
168k
                                          const LangOptions &LangOpts) {
545
168k
    // If this is not a trigraph and not a UCN or escaped newline, return
546
168k
    // quickly.
547
168k
    if (isObviouslySimpleCharacter(Ptr[0])) {
548
157k
      Size = 1;
549
157k
      return *Ptr;
550
157k
    }
551
10.5k
552
10.5k
    Size = 0;
553
10.5k
    return getCharAndSizeSlowNoWarn(Ptr, Size, LangOpts);
554
10.5k
  }
555
556
  /// Returns the leading whitespace for line that corresponds to the given
557
  /// location \p Loc.
558
  static StringRef getIndentationForLine(SourceLocation Loc,
559
                                         const SourceManager &SM);
560
561
private:
562
  //===--------------------------------------------------------------------===//
563
  // Internal implementation interfaces.
564
565
  /// LexTokenInternal - Internal interface to lex a preprocessing token. Called
566
  /// by Lex.
567
  ///
568
  bool LexTokenInternal(Token &Result, bool TokAtPhysicalStartOfLine);
569
570
  bool CheckUnicodeWhitespace(Token &Result, uint32_t C, const char *CurPtr);
571
572
  /// Given that a token begins with the Unicode character \p C, figure out
573
  /// what kind of token it is and dispatch to the appropriate lexing helper
574
  /// function.
575
  bool LexUnicode(Token &Result, uint32_t C, const char *CurPtr);
576
577
  /// FormTokenWithChars - When we lex a token, we have identified a span
578
  /// starting at BufferPtr, going to TokEnd that forms the token.  This method
579
  /// takes that range and assigns it to the token as its location and size.  In
580
  /// addition, since tokens cannot overlap, this also updates BufferPtr to be
581
  /// TokEnd.
582
  void FormTokenWithChars(Token &Result, const char *TokEnd,
583
1.97G
                          tok::TokenKind Kind) {
584
1.97G
    unsigned TokLen = TokEnd-BufferPtr;
585
1.97G
    Result.setLength(TokLen);
586
1.97G
    Result.setLocation(getSourceLocation(BufferPtr, TokLen));
587
1.97G
    Result.setKind(Kind);
588
1.97G
    BufferPtr = TokEnd;
589
1.97G
  }
590
591
  /// isNextPPTokenLParen - Return 1 if the next unexpanded token will return a
592
  /// tok::l_paren token, 0 if it is something else and 2 if there are no more
593
  /// tokens in the buffer controlled by this lexer.
594
  unsigned isNextPPTokenLParen();
595
596
  //===--------------------------------------------------------------------===//
597
  // Lexer character reading interfaces.
598
599
  // This lexer is built on two interfaces for reading characters, both of which
600
  // automatically provide phase 1/2 translation.  getAndAdvanceChar is used
601
  // when we know that we will be reading a character from the input buffer and
602
  // that this character will be part of the result token. This occurs in (f.e.)
603
  // string processing, because we know we need to read until we find the
604
  // closing '"' character.
605
  //
606
  // The second interface is the combination of getCharAndSize with
607
  // ConsumeChar.  getCharAndSize reads a phase 1/2 translated character,
608
  // returning it and its size.  If the lexer decides that this character is
609
  // part of the current token, it calls ConsumeChar on it.  This two stage
610
  // approach allows us to emit diagnostics for characters (e.g. warnings about
611
  // trigraphs), knowing that they only are emitted if the character is
612
  // consumed.
613
614
  /// isObviouslySimpleCharacter - Return true if the specified character is
615
  /// obviously the same in translation phase 1 and translation phase 3.  This
616
  /// can return false for characters that end up being the same, but it will
617
  /// never return true for something that needs to be mapped.
618
3.15G
  static bool isObviouslySimpleCharacter(char C) {
619
3.15G
    return C != '?' && 
C != '\\'3.15G
;
620
3.15G
  }
621
622
  /// getAndAdvanceChar - Read a single 'character' from the specified buffer,
623
  /// advance over it, and return it.  This is tricky in several cases.  Here we
624
  /// just handle the trivial case and fall-back to the non-inlined
625
  /// getCharAndSizeSlow method to handle the hard case.
626
2.45G
  inline char getAndAdvanceChar(const char *&Ptr, Token &Tok) {
627
2.45G
    // If this is not a trigraph and not a UCN or escaped newline, return
628
2.45G
    // quickly.
629
2.45G
    if (isObviouslySimpleCharacter(Ptr[0])) 
return *Ptr++2.45G
;
630
5.41M
631
5.41M
    unsigned Size = 0;
632
5.41M
    char C = getCharAndSizeSlow(Ptr, Size, &Tok);
633
5.41M
    Ptr += Size;
634
5.41M
    return C;
635
5.41M
  }
636
637
  /// ConsumeChar - When a character (identified by getCharAndSize) is consumed
638
  /// and added to a given token, check to see if there are diagnostics that
639
  /// need to be emitted or flags that need to be set on the token.  If so, do
640
  /// it.
641
256M
  const char *ConsumeChar(const char *Ptr, unsigned Size, Token &Tok) {
642
256M
    // Normal case, we consumed exactly one token.  Just return it.
643
256M
    if (Size == 1)
644
256M
      return Ptr+Size;
645
27
646
27
    // Otherwise, re-lex the character with a current token, allowing
647
27
    // diagnostics to be emitted and flags to be set.
648
27
    Size = 0;
649
27
    getCharAndSizeSlow(Ptr, Size, &Tok);
650
27
    return Ptr+Size;
651
27
  }
652
653
  /// getCharAndSize - Peek a single 'character' from the specified buffer,
654
  /// get its size, and return it.  This is tricky in several cases.  Here we
655
  /// just handle the trivial case and fall-back to the non-inlined
656
  /// getCharAndSizeSlow method to handle the hard case.
657
690M
  inline char getCharAndSize(const char *Ptr, unsigned &Size) {
658
690M
    // If this is not a trigraph and not a UCN or escaped newline, return
659
690M
    // quickly.
660
690M
    if (isObviouslySimpleCharacter(Ptr[0])) {
661
690M
      Size = 1;
662
690M
      return *Ptr;
663
690M
    }
664
7.04k
665
7.04k
    Size = 0;
666
7.04k
    return getCharAndSizeSlow(Ptr, Size);
667
7.04k
  }
668
669
  /// getCharAndSizeSlow - Handle the slow/uncommon case of the getCharAndSize
670
  /// method.
671
  char getCharAndSizeSlow(const char *Ptr, unsigned &Size,
672
                          Token *Tok = nullptr);
673
674
  /// getEscapedNewLineSize - Return the size of the specified escaped newline,
675
  /// or 0 if it is not an escaped newline. P[-1] is known to be a "\" on entry
676
  /// to this function.
677
  static unsigned getEscapedNewLineSize(const char *P);
678
679
  /// SkipEscapedNewLines - If P points to an escaped newline (or a series of
680
  /// them), skip over them and return the first non-escaped-newline found,
681
  /// otherwise return P.
682
  static const char *SkipEscapedNewLines(const char *P);
683
684
  /// getCharAndSizeSlowNoWarn - Same as getCharAndSizeSlow, but never emits a
685
  /// diagnostic.
686
  static char getCharAndSizeSlowNoWarn(const char *Ptr, unsigned &Size,
687
                                       const LangOptions &LangOpts);
688
689
  //===--------------------------------------------------------------------===//
690
  // Other lexer functions.
691
692
  void SetByteOffset(unsigned Offset, bool StartOfLine);
693
694
  void PropagateLineStartLeadingSpaceInfo(Token &Result);
695
696
  const char *LexUDSuffix(Token &Result, const char *CurPtr,
697
                          bool IsStringLiteral);
698
699
  // Helper functions to lex the remainder of a token of the specific type.
700
  bool LexIdentifier         (Token &Result, const char *CurPtr);
701
  bool LexNumericConstant    (Token &Result, const char *CurPtr);
702
  bool LexStringLiteral      (Token &Result, const char *CurPtr,
703
                              tok::TokenKind Kind);
704
  bool LexRawStringLiteral   (Token &Result, const char *CurPtr,
705
                              tok::TokenKind Kind);
706
  bool LexAngledStringLiteral(Token &Result, const char *CurPtr);
707
  bool LexCharConstant       (Token &Result, const char *CurPtr,
708
                              tok::TokenKind Kind);
709
  bool LexEndOfFile          (Token &Result, const char *CurPtr);
710
  bool SkipWhitespace        (Token &Result, const char *CurPtr,
711
                              bool &TokAtPhysicalStartOfLine);
712
  bool SkipLineComment       (Token &Result, const char *CurPtr,
713
                              bool &TokAtPhysicalStartOfLine);
714
  bool SkipBlockComment      (Token &Result, const char *CurPtr,
715
                              bool &TokAtPhysicalStartOfLine);
716
  bool SaveLineComment       (Token &Result, const char *CurPtr);
717
718
  bool IsStartOfConflictMarker(const char *CurPtr);
719
  bool HandleEndOfConflictMarker(const char *CurPtr);
720
721
  bool lexEditorPlaceholder(Token &Result, const char *CurPtr);
722
723
  bool isCodeCompletionPoint(const char *CurPtr) const;
724
61
  void cutOffLexing() { BufferPtr = BufferEnd; }
725
726
  bool isHexaLiteral(const char *Start, const LangOptions &LangOpts);
727
728
  void codeCompleteIncludedFile(const char *PathStart,
729
                                const char *CompletionPoint, bool IsAngled);
730
731
  /// Read a universal character name.
732
  ///
733
  /// \param StartPtr The position in the source buffer after the initial '\'.
734
  ///                 If the UCN is syntactically well-formed (but not 
735
  ///                 necessarily valid), this parameter will be updated to
736
  ///                 point to the character after the UCN.
737
  /// \param SlashLoc The position in the source buffer of the '\'.
738
  /// \param Result   The token being formed. Pass \c nullptr to suppress
739
  ///                 diagnostics and handle token formation in the caller.
740
  ///
741
  /// \return The Unicode codepoint specified by the UCN, or 0 if the UCN is
742
  ///         invalid.
743
  uint32_t tryReadUCN(const char *&StartPtr, const char *SlashLoc, Token *Result);
744
745
  /// Try to consume a UCN as part of an identifier at the current
746
  /// location.
747
  /// \param CurPtr Initially points to the range of characters in the source
748
  ///               buffer containing the '\'. Updated to point past the end of
749
  ///               the UCN on success.
750
  /// \param Size The number of characters occupied by the '\' (including
751
  ///             trigraphs and escaped newlines).
752
  /// \param Result The token being produced. Marked as containing a UCN on
753
  ///               success.
754
  /// \return \c true if a UCN was lexed and it produced an acceptable
755
  ///         identifier character, \c false otherwise.
756
  bool tryConsumeIdentifierUCN(const char *&CurPtr, unsigned Size,
757
                               Token &Result);
758
759
  /// Try to consume an identifier character encoded in UTF-8.
760
  /// \param CurPtr Points to the start of the (potential) UTF-8 code unit
761
  ///        sequence. On success, updated to point past the end of it.
762
  /// \return \c true if a UTF-8 sequence mapping to an acceptable identifier
763
  ///         character was lexed, \c false otherwise.
764
  bool tryConsumeIdentifierUTF8Char(const char *&CurPtr);
765
};
766
767
} // namespace clang
768
769
#endif // LLVM_CLANG_LEX_LEXER_H