clang  9.0.0svn
Token.h
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1 //===--- Token.h - Token interface ------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file defines the Token interface.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_CLANG_LEX_TOKEN_H
14 #define LLVM_CLANG_LEX_TOKEN_H
15 
17 #include "clang/Basic/TokenKinds.h"
18 #include "llvm/ADT/StringRef.h"
19 #include <cassert>
20 
21 namespace clang {
22 
23 class IdentifierInfo;
24 
25 /// Token - This structure provides full information about a lexed token.
26 /// It is not intended to be space efficient, it is intended to return as much
27 /// information as possible about each returned token. This is expected to be
28 /// compressed into a smaller form if memory footprint is important.
29 ///
30 /// The parser can create a special "annotation token" representing a stream of
31 /// tokens that were parsed and semantically resolved, e.g.: "foo::MyClass<int>"
32 /// can be represented by a single typename annotation token that carries
33 /// information about the SourceRange of the tokens and the type object.
34 class Token {
35  /// The location of the token. This is actually a SourceLocation.
36  unsigned Loc;
37 
38  // Conceptually these next two fields could be in a union. However, this
39  // causes gcc 4.2 to pessimize LexTokenInternal, a very performance critical
40  // routine. Keeping as separate members with casts until a more beautiful fix
41  // presents itself.
42 
43  /// UintData - This holds either the length of the token text, when
44  /// a normal token, or the end of the SourceRange when an annotation
45  /// token.
46  unsigned UintData;
47 
48  /// PtrData - This is a union of four different pointer types, which depends
49  /// on what type of token this is:
50  /// Identifiers, keywords, etc:
51  /// This is an IdentifierInfo*, which contains the uniqued identifier
52  /// spelling.
53  /// Literals: isLiteral() returns true.
54  /// This is a pointer to the start of the token in a text buffer, which
55  /// may be dirty (have trigraphs / escaped newlines).
56  /// Annotations (resolved type names, C++ scopes, etc): isAnnotation().
57  /// This is a pointer to sema-specific data for the annotation token.
58  /// Eof:
59  // This is a pointer to a Decl.
60  /// Other:
61  /// This is null.
62  void *PtrData;
63 
64  /// Kind - The actual flavor of token this is.
66 
67  /// Flags - Bits we track about this token, members of the TokenFlags enum.
68  unsigned short Flags;
69 
70 public:
71  // Various flags set per token:
72  enum TokenFlags {
73  StartOfLine = 0x01, // At start of line or only after whitespace
74  // (considering the line after macro expansion).
75  LeadingSpace = 0x02, // Whitespace exists before this token (considering
76  // whitespace after macro expansion).
77  DisableExpand = 0x04, // This identifier may never be macro expanded.
78  NeedsCleaning = 0x08, // Contained an escaped newline or trigraph.
79  LeadingEmptyMacro = 0x10, // Empty macro exists before this token.
80  HasUDSuffix = 0x20, // This string or character literal has a ud-suffix.
81  HasUCN = 0x40, // This identifier contains a UCN.
82  IgnoredComma = 0x80, // This comma is not a macro argument separator (MS).
83  StringifiedInMacro = 0x100, // This string or character literal is formed by
84  // macro stringizing or charizing operator.
85  CommaAfterElided = 0x200, // The comma following this token was elided (MS).
86  IsEditorPlaceholder = 0x400, // This identifier is a placeholder.
87  IsReinjected = 0x800, // A phase 4 token that was produced before and
88  // re-added, e.g. via EnterTokenStream. Annotation
89  // tokens are *not* reinjected.
90  };
91 
92  tok::TokenKind getKind() const { return Kind; }
93  void setKind(tok::TokenKind K) { Kind = K; }
94 
95  /// is/isNot - Predicates to check if this token is a specific kind, as in
96  /// "if (Tok.is(tok::l_brace)) {...}".
97  bool is(tok::TokenKind K) const { return Kind == K; }
98  bool isNot(tok::TokenKind K) const { return Kind != K; }
99  bool isOneOf(tok::TokenKind K1, tok::TokenKind K2) const {
100  return is(K1) || is(K2);
101  }
102  template <typename... Ts>
103  bool isOneOf(tok::TokenKind K1, tok::TokenKind K2, Ts... Ks) const {
104  return is(K1) || isOneOf(K2, Ks...);
105  }
106 
107  /// Return true if this is a raw identifier (when lexing
108  /// in raw mode) or a non-keyword identifier (when lexing in non-raw mode).
109  bool isAnyIdentifier() const {
110  return tok::isAnyIdentifier(getKind());
111  }
112 
113  /// Return true if this is a "literal", like a numeric
114  /// constant, string, etc.
115  bool isLiteral() const {
116  return tok::isLiteral(getKind());
117  }
118 
119  /// Return true if this is any of tok::annot_* kind tokens.
120  bool isAnnotation() const {
121  return tok::isAnnotation(getKind());
122  }
123 
124  /// Return a source location identifier for the specified
125  /// offset in the current file.
128  }
129  unsigned getLength() const {
130  assert(!isAnnotation() && "Annotation tokens have no length field");
131  return UintData;
132  }
133 
135  void setLength(unsigned Len) {
136  assert(!isAnnotation() && "Annotation tokens have no length field");
137  UintData = Len;
138  }
139 
141  assert(isAnnotation() && "Used AnnotEndLocID on non-annotation token");
142  return SourceLocation::getFromRawEncoding(UintData ? UintData : Loc);
143  }
145  assert(isAnnotation() && "Used AnnotEndLocID on non-annotation token");
146  UintData = L.getRawEncoding();
147  }
148 
151  }
152 
154  return isAnnotation() ? getAnnotationEndLoc()
156  }
157 
158  /// SourceRange of the group of tokens that this annotation token
159  /// represents.
162  }
164  setLocation(R.getBegin());
166  }
167 
168  const char *getName() const { return tok::getTokenName(Kind); }
169 
170  /// Reset all flags to cleared.
171  void startToken() {
172  Kind = tok::unknown;
173  Flags = 0;
174  PtrData = nullptr;
175  UintData = 0;
176  Loc = SourceLocation().getRawEncoding();
177  }
178 
180  assert(isNot(tok::raw_identifier) &&
181  "getIdentifierInfo() on a tok::raw_identifier token!");
182  assert(!isAnnotation() &&
183  "getIdentifierInfo() on an annotation token!");
184  if (isLiteral()) return nullptr;
185  if (is(tok::eof)) return nullptr;
186  return (IdentifierInfo*) PtrData;
187  }
189  PtrData = (void*) II;
190  }
191 
192  const void *getEofData() const {
193  assert(is(tok::eof));
194  return reinterpret_cast<const void *>(PtrData);
195  }
196  void setEofData(const void *D) {
197  assert(is(tok::eof));
198  assert(!PtrData);
199  PtrData = const_cast<void *>(D);
200  }
201 
202  /// getRawIdentifier - For a raw identifier token (i.e., an identifier
203  /// lexed in raw mode), returns a reference to the text substring in the
204  /// buffer if known.
205  StringRef getRawIdentifier() const {
206  assert(is(tok::raw_identifier));
207  return StringRef(reinterpret_cast<const char *>(PtrData), getLength());
208  }
209  void setRawIdentifierData(const char *Ptr) {
210  assert(is(tok::raw_identifier));
211  PtrData = const_cast<char*>(Ptr);
212  }
213 
214  /// getLiteralData - For a literal token (numeric constant, string, etc), this
215  /// returns a pointer to the start of it in the text buffer if known, null
216  /// otherwise.
217  const char *getLiteralData() const {
218  assert(isLiteral() && "Cannot get literal data of non-literal");
219  return reinterpret_cast<const char*>(PtrData);
220  }
221  void setLiteralData(const char *Ptr) {
222  assert(isLiteral() && "Cannot set literal data of non-literal");
223  PtrData = const_cast<char*>(Ptr);
224  }
225 
226  void *getAnnotationValue() const {
227  assert(isAnnotation() && "Used AnnotVal on non-annotation token");
228  return PtrData;
229  }
230  void setAnnotationValue(void *val) {
231  assert(isAnnotation() && "Used AnnotVal on non-annotation token");
232  PtrData = val;
233  }
234 
235  /// Set the specified flag.
236  void setFlag(TokenFlags Flag) {
237  Flags |= Flag;
238  }
239 
240  /// Get the specified flag.
241  bool getFlag(TokenFlags Flag) const {
242  return (Flags & Flag) != 0;
243  }
244 
245  /// Unset the specified flag.
246  void clearFlag(TokenFlags Flag) {
247  Flags &= ~Flag;
248  }
249 
250  /// Return the internal represtation of the flags.
251  ///
252  /// This is only intended for low-level operations such as writing tokens to
253  /// disk.
254  unsigned getFlags() const {
255  return Flags;
256  }
257 
258  /// Set a flag to either true or false.
259  void setFlagValue(TokenFlags Flag, bool Val) {
260  if (Val)
261  setFlag(Flag);
262  else
263  clearFlag(Flag);
264  }
265 
266  /// isAtStartOfLine - Return true if this token is at the start of a line.
267  ///
268  bool isAtStartOfLine() const { return getFlag(StartOfLine); }
269 
270  /// Return true if this token has whitespace before it.
271  ///
272  bool hasLeadingSpace() const { return getFlag(LeadingSpace); }
273 
274  /// Return true if this identifier token should never
275  /// be expanded in the future, due to C99 6.10.3.4p2.
276  bool isExpandDisabled() const { return getFlag(DisableExpand); }
277 
278  /// Return true if we have an ObjC keyword identifier.
279  bool isObjCAtKeyword(tok::ObjCKeywordKind objcKey) const;
280 
281  /// Return the ObjC keyword kind.
283 
284  /// Return true if this token has trigraphs or escaped newlines in it.
285  bool needsCleaning() const { return getFlag(NeedsCleaning); }
286 
287  /// Return true if this token has an empty macro before it.
288  ///
290 
291  /// Return true if this token is a string or character literal which
292  /// has a ud-suffix.
293  bool hasUDSuffix() const { return getFlag(HasUDSuffix); }
294 
295  /// Returns true if this token contains a universal character name.
296  bool hasUCN() const { return getFlag(HasUCN); }
297 
298  /// Returns true if this token is formed by macro by stringizing or charizing
299  /// operator.
301 
302  /// Returns true if the comma after this token was elided.
303  bool commaAfterElided() const { return getFlag(CommaAfterElided); }
304 
305  /// Returns true if this token is an editor placeholder.
306  ///
307  /// Editor placeholders are produced by the code-completion engine and are
308  /// represented as characters between '<#' and '#>' in the source code. The
309  /// lexer uses identifier tokens to represent placeholders.
311 };
312 
313 /// Information about the conditional stack (\#if directives)
314 /// currently active.
316  /// Location where the conditional started.
318 
319  /// True if this was contained in a skipping directive, e.g.,
320  /// in a "\#if 0" block.
322 
323  /// True if we have emitted tokens already, and now we're in
324  /// an \#else block or something. Only useful in Skipping blocks.
326 
327  /// True if we've seen a \#else in this block. If so,
328  /// \#elif/\#else directives are not allowed.
329  bool FoundElse;
330 };
331 
332 } // end namespace clang
333 
334 #endif // LLVM_CLANG_LEX_TOKEN_H
SourceLocation getLocWithOffset(int Offset) const
Return a source location with the specified offset from this SourceLocation.
unsigned getRawEncoding() const
When a SourceLocation itself cannot be used, this returns an (opaque) 32-bit integer encoding for it...
void setFlagValue(TokenFlags Flag, bool Val)
Set a flag to either true or false.
Definition: Token.h:259
bool is(tok::TokenKind K) const
is/isNot - Predicates to check if this token is a specific kind, as in "if (Tok.is(tok::l_brace)) {...
Definition: Token.h:97
void setFlag(TokenFlags Flag)
Set the specified flag.
Definition: Token.h:236
bool isAnyIdentifier() const
Return true if this is a raw identifier (when lexing in raw mode) or a non-keyword identifier (when l...
Definition: Token.h:109
bool isAnnotation() const
Return true if this is any of tok::annot_* kind tokens.
Definition: Token.h:120
tok::TokenKind getKind() const
Definition: Token.h:92
bool isLiteral() const
Return true if this is a "literal", like a numeric constant, string, etc.
Definition: Token.h:115
One of these records is kept for each identifier that is lexed.
SourceLocation getAnnotationEndLoc() const
Definition: Token.h:140
void setRawIdentifierData(const char *Ptr)
Definition: Token.h:209
static SourceLocation getFromRawEncoding(unsigned Encoding)
Turn a raw encoding of a SourceLocation object into a real SourceLocation.
Token - This structure provides full information about a lexed token.
Definition: Token.h:34
void setKind(tok::TokenKind K)
Definition: Token.h:93
bool isObjCAtKeyword(tok::ObjCKeywordKind objcKey) const
Return true if we have an ObjC keyword identifier.
Definition: Lexer.cpp:57
bool hasUDSuffix() const
Return true if this token is a string or character literal which has a ud-suffix. ...
Definition: Token.h:293
SourceRange getAnnotationRange() const
SourceRange of the group of tokens that this annotation token represents.
Definition: Token.h:160
bool commaAfterElided() const
Returns true if the comma after this token was elided.
Definition: Token.h:303
bool FoundNonSkip
True if we have emitted tokens already, and now we&#39;re in an #else block or something.
Definition: Token.h:325
const char * getName() const
Definition: Token.h:168
void setAnnotationRange(SourceRange R)
Definition: Token.h:163
void setAnnotationValue(void *val)
Definition: Token.h:230
bool hasLeadingEmptyMacro() const
Return true if this token has an empty macro before it.
Definition: Token.h:289
void setEofData(const void *D)
Definition: Token.h:196
SourceLocation getLocation() const
Return a source location identifier for the specified offset in the current file. ...
Definition: Token.h:126
Information about the conditional stack (#if directives) currently active.
Definition: Token.h:315
SourceLocation getEnd() const
ObjCKeywordKind
Provides a namespace for Objective-C keywords which start with an &#39;@&#39;.
Definition: TokenKinds.h:40
bool isExpandDisabled() const
Return true if this identifier token should never be expanded in the future, due to C99 6...
Definition: Token.h:276
Kind
bool WasSkipping
True if this was contained in a skipping directive, e.g., in a "\#if 0" block.
Definition: Token.h:321
Encodes a location in the source.
void setLength(unsigned Len)
Definition: Token.h:135
bool isAnnotation(TokenKind K)
Return true if this is any of tok::annot_* kinds.
Definition: TokenKinds.h:93
IdentifierInfo * getIdentifierInfo() const
Definition: Token.h:179
void setAnnotationEndLoc(SourceLocation L)
Definition: Token.h:144
void setIdentifierInfo(IdentifierInfo *II)
Definition: Token.h:188
const void * getEofData() const
Definition: Token.h:192
bool isLiteral(TokenKind K)
Return true if this is a "literal" kind, like a numeric constant, string, etc.
Definition: TokenKinds.h:85
bool isAtStartOfLine() const
isAtStartOfLine - Return true if this token is at the start of a line.
Definition: Token.h:268
TokenKind
Provides a simple uniform namespace for tokens from all C languages.
Definition: TokenKinds.h:24
tok::ObjCKeywordKind getObjCKeywordID() const
Return the ObjC keyword kind.
Definition: Lexer.cpp:66
SourceLocation IfLoc
Location where the conditional started.
Definition: Token.h:317
bool isNot(tok::TokenKind K) const
Definition: Token.h:98
Dataflow Directional Tag Classes.
bool getFlag(TokenFlags Flag) const
Get the specified flag.
Definition: Token.h:241
bool isOneOf(tok::TokenKind K1, tok::TokenKind K2) const
Definition: Token.h:99
unsigned getLength() const
Definition: Token.h:129
void setLiteralData(const char *Ptr)
Definition: Token.h:221
const char * getLiteralData() const
getLiteralData - For a literal token (numeric constant, string, etc), this returns a pointer to the s...
Definition: Token.h:217
bool isOneOf(tok::TokenKind K1, tok::TokenKind K2, Ts... Ks) const
Definition: Token.h:103
Defines the clang::TokenKind enum and support functions.
Defines the clang::SourceLocation class and associated facilities.
StringRef getRawIdentifier() const
getRawIdentifier - For a raw identifier token (i.e., an identifier lexed in raw mode), returns a reference to the text substring in the buffer if known.
Definition: Token.h:205
SourceLocation getLastLoc() const
Definition: Token.h:149
const char * getTokenName(TokenKind Kind) LLVM_READNONE
Determines the name of a token as used within the front end.
Definition: TokenKinds.cpp:24
bool needsCleaning() const
Return true if this token has trigraphs or escaped newlines in it.
Definition: Token.h:285
bool stringifiedInMacro() const
Returns true if this token is formed by macro by stringizing or charizing operator.
Definition: Token.h:300
void setLocation(SourceLocation L)
Definition: Token.h:134
A trivial tuple used to represent a source range.
unsigned getFlags() const
Return the internal represtation of the flags.
Definition: Token.h:254
void clearFlag(TokenFlags Flag)
Unset the specified flag.
Definition: Token.h:246
bool hasUCN() const
Returns true if this token contains a universal character name.
Definition: Token.h:296
bool isEditorPlaceholder() const
Returns true if this token is an editor placeholder.
Definition: Token.h:310
bool FoundElse
True if we&#39;ve seen a #else in this block.
Definition: Token.h:329
void * getAnnotationValue() const
Definition: Token.h:226
SourceLocation getBegin() const
bool isAnyIdentifier(TokenKind K)
Return true if this is a raw identifier or an identifier kind.
Definition: TokenKinds.h:71
bool hasLeadingSpace() const
Return true if this token has whitespace before it.
Definition: Token.h:272
void startToken()
Reset all flags to cleared.
Definition: Token.h:171
SourceLocation getEndLoc() const
Definition: Token.h:153