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
16#include "clang/Basic/SourceLocation.h"
17#include "clang/Basic/TokenKinds.h"
18#include "llvm/ADT/ArrayRef.h"
19#include "llvm/ADT/StringRef.h"
20#include <cassert>
21
22namespace clang {
23
24class IdentifierInfo;
25class LangOptions;
26
27/// Token - This structure provides full information about a lexed token.
28/// It is not intended to be space efficient, it is intended to return as much
29/// information as possible about each returned token. This is expected to be
30/// compressed into a smaller form if memory footprint is important.
31///
32/// The parser can create a special "annotation token" representing a stream of
33/// tokens that were parsed and semantically resolved, e.g.: "foo::MyClass<int>"
34/// can be represented by a single typename annotation token that carries
35/// information about the SourceRange of the tokens and the type object.
36class Token {
37 /// The location of the token. This is actually a SourceLocation.
38 SourceLocation::UIntTy Loc;
39
40 // Conceptually these next two fields could be in a union. However, this
41 // causes gcc 4.2 to pessimize LexTokenInternal, a very performance critical
42 // routine. Keeping as separate members with casts until a more beautiful fix
43 // presents itself.
44
45 /// UintData - This holds either the length of the token text, when
46 /// a normal token, or the end of the SourceRange when an annotation
47 /// token.
48 SourceLocation::UIntTy UintData;
49
50 /// PtrData - This is a union of four different pointer types, which depends
51 /// on what type of token this is:
52 /// Identifiers, keywords, etc:
53 /// This is an IdentifierInfo*, which contains the uniqued identifier
54 /// spelling.
55 /// Literals: isLiteral() returns true.
56 /// This is a pointer to the start of the token in a text buffer, which
57 /// may be dirty (have trigraphs / escaped newlines).
58 /// Annotations (resolved type names, C++ scopes, etc): isAnnotation().
59 /// This is a pointer to sema-specific data for the annotation token.
60 /// Eof:
61 // This is a pointer to a Decl.
62 /// Other:
63 /// This is null.
64 void *PtrData;
65
66 /// Kind - The actual flavor of token this is.
67 tok::TokenKind Kind;
68
69 /// Flags - Bits we track about this token, members of the TokenFlags enum.
70 unsigned short Flags;
71
72public:
73 // Various flags set per token:
74 enum TokenFlags {
75 StartOfLine = 0x01, // At start of line or only after whitespace
76 // (considering the line after macro expansion).
77 LeadingSpace = 0x02, // Whitespace exists before this token (considering
78 // whitespace after macro expansion).
79 DisableExpand = 0x04, // This identifier may never be macro expanded.
80 NeedsCleaning = 0x08, // Contained an escaped newline or trigraph.
81 LeadingEmptyMacro = 0x10, // Empty macro exists before this token.
82 HasUDSuffix = 0x20, // This string or character literal has a ud-suffix.
83 HasUCN = 0x40, // This identifier contains a UCN.
84 IgnoredComma = 0x80, // This comma is not a macro argument separator (MS).
85 StringifiedInMacro = 0x100, // This string or character literal is formed by
86 // macro stringizing or charizing operator.
87 CommaAfterElided = 0x200, // The comma following this token was elided (MS).
88 IsEditorPlaceholder = 0x400, // This identifier is a placeholder.
89 IsReinjected = 0x800, // A phase 4 token that was produced before and
90 // re-added, e.g. via EnterTokenStream. Annotation
91 // tokens are *not* reinjected.
92 };
93
94 tok::TokenKind getKind() const { return Kind; }
95 void setKind(tok::TokenKind K) { Kind = K; }
96
97 /// is/isNot - Predicates to check if this token is a specific kind, as in
98 /// "if (Tok.is(tok::l_brace)) {...}".
99 bool is(tok::TokenKind K) const { return Kind == K; }
100 bool isNot(tok::TokenKind K) const { return Kind != K; }
101 bool isOneOf(tok::TokenKind K1, tok::TokenKind K2) const {
102 return is(K: K1) || is(K: K2);
103 }
104 template <typename... Ts> bool isOneOf(tok::TokenKind K1, Ts... Ks) const {
105 return is(K: K1) || isOneOf(Ks...);
106 }
107
108 /// Return true if this is a raw identifier (when lexing
109 /// in raw mode) or a non-keyword identifier (when lexing in non-raw mode).
110 bool isAnyIdentifier() const {
111 return tok::isAnyIdentifier(K: getKind());
112 }
113
114 /// Return true if this is a "literal", like a numeric
115 /// constant, string, etc.
116 bool isLiteral() const {
117 return tok::isLiteral(K: getKind());
118 }
119
120 /// Return true if this is any of tok::annot_* kind tokens.
121 bool isAnnotation() const { return tok::isAnnotation(K: getKind()); }
122
123 /// Return true if the token is a keyword that is parsed in the same
124 /// position as a standard attribute, but that has semantic meaning
125 /// and so cannot be a true attribute.
126 bool isRegularKeywordAttribute() const {
127 return tok::isRegularKeywordAttribute(K: getKind());
128 }
129
130 /// Return a source location identifier for the specified
131 /// offset in the current file.
132 SourceLocation getLocation() const {
133 return SourceLocation::getFromRawEncoding(Encoding: Loc);
134 }
135 unsigned getLength() const {
136 assert(!isAnnotation() && "Annotation tokens have no length field");
137 return UintData;
138 }
139
140 void setLocation(SourceLocation L) { Loc = L.getRawEncoding(); }
141 void setLength(unsigned Len) {
142 assert(!isAnnotation() && "Annotation tokens have no length field");
143 UintData = Len;
144 }
145
146 SourceLocation getAnnotationEndLoc() const {
147 assert(isAnnotation() && "Used AnnotEndLocID on non-annotation token");
148 return SourceLocation::getFromRawEncoding(Encoding: UintData ? UintData : Loc);
149 }
150 void setAnnotationEndLoc(SourceLocation L) {
151 assert(isAnnotation() && "Used AnnotEndLocID on non-annotation token");
152 UintData = L.getRawEncoding();
153 }
154
155 SourceLocation getLastLoc() const {
156 return isAnnotation() ? getAnnotationEndLoc() : getLocation();
157 }
158
159 SourceLocation getEndLoc() const {
160 return isAnnotation() ? getAnnotationEndLoc()
161 : getLocation().getLocWithOffset(Offset: getLength());
162 }
163
164 /// SourceRange of the group of tokens that this annotation token
165 /// represents.
166 SourceRange getAnnotationRange() const {
167 return SourceRange(getLocation(), getAnnotationEndLoc());
168 }
169 void setAnnotationRange(SourceRange R) {
170 setLocation(R.getBegin());
171 setAnnotationEndLoc(R.getEnd());
172 }
173
174 const char *getName() const { return tok::getTokenName(Kind); }
175
176 /// Reset all flags to cleared.
177 void startToken() {
178 Kind = tok::unknown;
179 Flags = 0;
180 PtrData = nullptr;
181 UintData = 0;
182 Loc = SourceLocation().getRawEncoding();
183 }
184
185 bool hasPtrData() const { return PtrData != nullptr; }
186
187 IdentifierInfo *getIdentifierInfo() const {
188 assert(isNot(tok::raw_identifier) &&
189 "getIdentifierInfo() on a tok::raw_identifier token!");
190 assert(!isAnnotation() &&
191 "getIdentifierInfo() on an annotation token!");
192 if (isLiteral()) return nullptr;
193 if (is(K: tok::eof)) return nullptr;
194 return (IdentifierInfo*) PtrData;
195 }
196 void setIdentifierInfo(IdentifierInfo *II) {
197 PtrData = (void*) II;
198 }
199
200 const void *getEofData() const {
201 assert(is(tok::eof));
202 return reinterpret_cast<const void *>(PtrData);
203 }
204 void setEofData(const void *D) {
205 assert(is(tok::eof));
206 assert(!PtrData);
207 PtrData = const_cast<void *>(D);
208 }
209
210 /// getRawIdentifier - For a raw identifier token (i.e., an identifier
211 /// lexed in raw mode), returns a reference to the text substring in the
212 /// buffer if known.
213 StringRef getRawIdentifier() const {
214 assert(is(tok::raw_identifier));
215 return StringRef(reinterpret_cast<const char *>(PtrData), getLength());
216 }
217 void setRawIdentifierData(const char *Ptr) {
218 assert(is(tok::raw_identifier));
219 PtrData = const_cast<char*>(Ptr);
220 }
221
222 /// getLiteralData - For a literal token (numeric constant, string, etc), this
223 /// returns a pointer to the start of it in the text buffer if known, null
224 /// otherwise.
225 const char *getLiteralData() const {
226 assert(isLiteral() && "Cannot get literal data of non-literal");
227 return reinterpret_cast<const char*>(PtrData);
228 }
229 void setLiteralData(const char *Ptr) {
230 assert(isLiteral() && "Cannot set literal data of non-literal");
231 PtrData = const_cast<char*>(Ptr);
232 }
233
234 void *getAnnotationValue() const {
235 assert(isAnnotation() && "Used AnnotVal on non-annotation token");
236 return PtrData;
237 }
238 void setAnnotationValue(void *val) {
239 assert(isAnnotation() && "Used AnnotVal on non-annotation token");
240 PtrData = val;
241 }
242
243 /// Set the specified flag.
244 void setFlag(TokenFlags Flag) {
245 Flags |= Flag;
246 }
247
248 /// Get the specified flag.
249 bool getFlag(TokenFlags Flag) const {
250 return (Flags & Flag) != 0;
251 }
252
253 /// Unset the specified flag.
254 void clearFlag(TokenFlags Flag) {
255 Flags &= ~Flag;
256 }
257
258 /// Return the internal represtation of the flags.
259 ///
260 /// This is only intended for low-level operations such as writing tokens to
261 /// disk.
262 unsigned getFlags() const {
263 return Flags;
264 }
265
266 /// Set a flag to either true or false.
267 void setFlagValue(TokenFlags Flag, bool Val) {
268 if (Val)
269 setFlag(Flag);
270 else
271 clearFlag(Flag);
272 }
273
274 /// isAtStartOfLine - Return true if this token is at the start of a line.
275 ///
276 bool isAtStartOfLine() const { return getFlag(Flag: StartOfLine); }
277
278 /// Return true if this token has whitespace before it.
279 ///
280 bool hasLeadingSpace() const { return getFlag(Flag: LeadingSpace); }
281
282 /// Return true if this identifier token should never
283 /// be expanded in the future, due to C99 6.10.3.4p2.
284 bool isExpandDisabled() const { return getFlag(Flag: DisableExpand); }
285
286 /// Return true if we have an ObjC keyword identifier.
287 bool isObjCAtKeyword(tok::ObjCKeywordKind objcKey) const;
288
289 /// Return the ObjC keyword kind.
290 tok::ObjCKeywordKind getObjCKeywordID() const;
291
292 bool isSimpleTypeSpecifier(const LangOptions &LangOpts) const;
293
294 /// Return true if this token has trigraphs or escaped newlines in it.
295 bool needsCleaning() const { return getFlag(Flag: NeedsCleaning); }
296
297 /// Return true if this token has an empty macro before it.
298 ///
299 bool hasLeadingEmptyMacro() const { return getFlag(Flag: LeadingEmptyMacro); }
300
301 /// Return true if this token is a string or character literal which
302 /// has a ud-suffix.
303 bool hasUDSuffix() const { return getFlag(Flag: HasUDSuffix); }
304
305 /// Returns true if this token contains a universal character name.
306 bool hasUCN() const { return getFlag(Flag: HasUCN); }
307
308 /// Returns true if this token is formed by macro by stringizing or charizing
309 /// operator.
310 bool stringifiedInMacro() const { return getFlag(Flag: StringifiedInMacro); }
311
312 /// Returns true if the comma after this token was elided.
313 bool commaAfterElided() const { return getFlag(Flag: CommaAfterElided); }
314
315 /// Returns true if this token is an editor placeholder.
316 ///
317 /// Editor placeholders are produced by the code-completion engine and are
318 /// represented as characters between '<#' and '#>' in the source code. The
319 /// lexer uses identifier tokens to represent placeholders.
320 bool isEditorPlaceholder() const { return getFlag(Flag: IsEditorPlaceholder); }
321};
322
323/// Information about the conditional stack (\#if directives)
324/// currently active.
325struct PPConditionalInfo {
326 /// Location where the conditional started.
327 SourceLocation IfLoc;
328
329 /// True if this was contained in a skipping directive, e.g.,
330 /// in a "\#if 0" block.
331 bool WasSkipping;
332
333 /// True if we have emitted tokens already, and now we're in
334 /// an \#else block or something. Only useful in Skipping blocks.
335 bool FoundNonSkip;
336
337 /// True if we've seen a \#else in this block. If so,
338 /// \#elif/\#else directives are not allowed.
339 bool FoundElse;
340};
341
342// Extra information needed for annonation tokens.
343struct PragmaLoopHintInfo {
344 Token PragmaName;
345 Token Option;
346 ArrayRef<Token> Toks;
347};
348} // end namespace clang
349
350#endif // LLVM_CLANG_LEX_TOKEN_H
351

source code of clang/include/clang/Lex/Token.h