1//===--- Token.h - Token interface ------------------------------*- C++ -*-===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines the Token interface.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_CLANG_LEX_TOKEN_H
15#define LLVM_CLANG_LEX_TOKEN_H
16
17#include "clang/Basic/SourceLocation.h"
18#include "clang/Basic/TokenKinds.h"
19#include "llvm/ADT/StringRef.h"
20#include <cassert>
21
22namespace clang {
23
24class IdentifierInfo;
25
26/// Token - This structure provides full information about a lexed token.
27/// It is not intended to be space efficient, it is intended to return as much
28/// information as possible about each returned token. This is expected to be
29/// compressed into a smaller form if memory footprint is important.
30///
31/// The parser can create a special "annotation token" representing a stream of
32/// tokens that were parsed and semantically resolved, e.g.: "foo::MyClass<int>"
33/// can be represented by a single typename annotation token that carries
34/// information about the SourceRange of the tokens and the type object.
35class Token {
36 /// The location of the token. This is actually a SourceLocation.
37 unsigned Loc;
38
39 // Conceptually these next two fields could be in a union. However, this
40 // causes gcc 4.2 to pessimize LexTokenInternal, a very performance critical
41 // routine. Keeping as separate members with casts until a more beautiful fix
42 // presents itself.
43
44 /// UintData - This holds either the length of the token text, when
45 /// a normal token, or the end of the SourceRange when an annotation
46 /// token.
47 unsigned UintData;
48
49 /// PtrData - This is a union of four different pointer types, which depends
50 /// on what type of token this is:
51 /// Identifiers, keywords, etc:
52 /// This is an IdentifierInfo*, which contains the uniqued identifier
53 /// spelling.
54 /// Literals: isLiteral() returns true.
55 /// This is a pointer to the start of the token in a text buffer, which
56 /// may be dirty (have trigraphs / escaped newlines).
57 /// Annotations (resolved type names, C++ scopes, etc): isAnnotation().
58 /// This is a pointer to sema-specific data for the annotation token.
59 /// Eof:
60 // This is a pointer to a Decl.
61 /// Other:
62 /// This is null.
63 void *PtrData;
64
65 /// Kind - The actual flavor of token this is.
66 tok::TokenKind Kind;
67
68 /// Flags - Bits we track about this token, members of the TokenFlags enum.
69 unsigned short Flags;
70
71public:
72 // Various flags set per token:
73 enum TokenFlags {
74 StartOfLine = 0x01, // At start of line or only after whitespace
75 // (considering the line after macro expansion).
76 LeadingSpace = 0x02, // Whitespace exists before this token (considering
77 // whitespace after macro expansion).
78 DisableExpand = 0x04, // This identifier may never be macro expanded.
79 NeedsCleaning = 0x08, // Contained an escaped newline or trigraph.
80 LeadingEmptyMacro = 0x10, // Empty macro exists before this token.
81 HasUDSuffix = 0x20, // This string or character literal has a ud-suffix.
82 HasUCN = 0x40, // This identifier contains a UCN.
83 IgnoredComma = 0x80, // This comma is not a macro argument separator (MS).
84 StringifiedInMacro = 0x100, // This string or character literal is formed by
85 // macro stringizing or charizing operator.
86 CommaAfterElided = 0x200, // The comma following this token was elided (MS).
87 IsEditorPlaceholder = 0x400, // This identifier is a placeholder.
88 };
89
90 tok::TokenKind getKind() const { return Kind; }
91 void setKind(tok::TokenKind K) { Kind = K; }
92
93 /// is/isNot - Predicates to check if this token is a specific kind, as in
94 /// "if (Tok.is(tok::l_brace)) {...}".
95 bool is(tok::TokenKind K) const { return Kind == K; }
96 bool isNot(tok::TokenKind K) const { return Kind != K; }
97 bool isOneOf(tok::TokenKind K1, tok::TokenKind K2) const {
98 return is(K1) || is(K2);
99 }
100 template <typename... Ts>
101 bool isOneOf(tok::TokenKind K1, tok::TokenKind K2, Ts... Ks) const {
102 return is(K1) || isOneOf(K2, Ks...);
103 }
104
105 /// Return true if this is a raw identifier (when lexing
106 /// in raw mode) or a non-keyword identifier (when lexing in non-raw mode).
107 bool isAnyIdentifier() const {
108 return tok::isAnyIdentifier(getKind());
109 }
110
111 /// Return true if this is a "literal", like a numeric
112 /// constant, string, etc.
113 bool isLiteral() const {
114 return tok::isLiteral(getKind());
115 }
116
117 /// Return true if this is any of tok::annot_* kind tokens.
118 bool isAnnotation() const {
119 return tok::isAnnotation(getKind());
120 }
121
122 /// Return a source location identifier for the specified
123 /// offset in the current file.
124 SourceLocation getLocation() const {
125 return SourceLocation::getFromRawEncoding(Loc);
126 }
127 unsigned getLength() const {
128 assert(!isAnnotation() && "Annotation tokens have no length field");
129 return UintData;
130 }
131
132 void setLocation(SourceLocation L) { Loc = L.getRawEncoding(); }
133 void setLength(unsigned Len) {
134 assert(!isAnnotation() && "Annotation tokens have no length field");
135 UintData = Len;
136 }
137
138 SourceLocation getAnnotationEndLoc() const {
139 assert(isAnnotation() && "Used AnnotEndLocID on non-annotation token");
140 return SourceLocation::getFromRawEncoding(UintData ? UintData : Loc);
141 }
142 void setAnnotationEndLoc(SourceLocation L) {
143 assert(isAnnotation() && "Used AnnotEndLocID on non-annotation token");
144 UintData = L.getRawEncoding();
145 }
146
147 SourceLocation getLastLoc() const {
148 return isAnnotation() ? getAnnotationEndLoc() : getLocation();
149 }
150
151 SourceLocation getEndLoc() const {
152 return isAnnotation() ? getAnnotationEndLoc()
153 : getLocation().getLocWithOffset(getLength());
154 }
155
156 /// SourceRange of the group of tokens that this annotation token
157 /// represents.
158 SourceRange getAnnotationRange() const {
159 return SourceRange(getLocation(), getAnnotationEndLoc());
160 }
161 void setAnnotationRange(SourceRange R) {
162 setLocation(R.getBegin());
163 setAnnotationEndLoc(R.getEnd());
164 }
165
166 const char *getName() const { return tok::getTokenName(Kind); }
167
168 /// Reset all flags to cleared.
169 void startToken() {
170 Kind = tok::unknown;
171 Flags = 0;
172 PtrData = nullptr;
173 UintData = 0;
174 Loc = SourceLocation().getRawEncoding();
175 }
176
177 IdentifierInfo *getIdentifierInfo() const {
178 assert(isNot(tok::raw_identifier) &&
179 "getIdentifierInfo() on a tok::raw_identifier token!");
180 assert(!isAnnotation() &&
181 "getIdentifierInfo() on an annotation token!");
182 if (isLiteral()) return nullptr;
183 if (is(tok::eof)) return nullptr;
184 return (IdentifierInfo*) PtrData;
185 }
186 void setIdentifierInfo(IdentifierInfo *II) {
187 PtrData = (void*) II;
188 }
189
190 const void *getEofData() const {
191 assert(is(tok::eof));
192 return reinterpret_cast<const void *>(PtrData);
193 }
194 void setEofData(const void *D) {
195 assert(is(tok::eof));
196 assert(!PtrData);
197 PtrData = const_cast<void *>(D);
198 }
199
200 /// getRawIdentifier - For a raw identifier token (i.e., an identifier
201 /// lexed in raw mode), returns a reference to the text substring in the
202 /// buffer if known.
203 StringRef getRawIdentifier() const {
204 assert(is(tok::raw_identifier));
205 return StringRef(reinterpret_cast<const char *>(PtrData), getLength());
206 }
207 void setRawIdentifierData(const char *Ptr) {
208 assert(is(tok::raw_identifier));
209 PtrData = const_cast<char*>(Ptr);
210 }
211
212 /// getLiteralData - For a literal token (numeric constant, string, etc), this
213 /// returns a pointer to the start of it in the text buffer if known, null
214 /// otherwise.
215 const char *getLiteralData() const {
216 assert(isLiteral() && "Cannot get literal data of non-literal");
217 return reinterpret_cast<const char*>(PtrData);
218 }
219 void setLiteralData(const char *Ptr) {
220 assert(isLiteral() && "Cannot set literal data of non-literal");
221 PtrData = const_cast<char*>(Ptr);
222 }
223
224 void *getAnnotationValue() const {
225 assert(isAnnotation() && "Used AnnotVal on non-annotation token");
226 return PtrData;
227 }
228 void setAnnotationValue(void *val) {
229 assert(isAnnotation() && "Used AnnotVal on non-annotation token");
230 PtrData = val;
231 }
232
233 /// Set the specified flag.
234 void setFlag(TokenFlags Flag) {
235 Flags |= Flag;
236 }
237
238 /// Get the specified flag.
239 bool getFlag(TokenFlags Flag) const {
240 return (Flags & Flag) != 0;
241 }
242
243 /// Unset the specified flag.
244 void clearFlag(TokenFlags Flag) {
245 Flags &= ~Flag;
246 }
247
248 /// Return the internal represtation of the flags.
249 ///
250 /// This is only intended for low-level operations such as writing tokens to
251 /// disk.
252 unsigned getFlags() const {
253 return Flags;
254 }
255
256 /// Set a flag to either true or false.
257 void setFlagValue(TokenFlags Flag, bool Val) {
258 if (Val)
259 setFlag(Flag);
260 else
261 clearFlag(Flag);
262 }
263
264 /// isAtStartOfLine - Return true if this token is at the start of a line.
265 ///
266 bool isAtStartOfLine() const { return getFlag(StartOfLine); }
267
268 /// Return true if this token has whitespace before it.
269 ///
270 bool hasLeadingSpace() const { return getFlag(LeadingSpace); }
271
272 /// Return true if this identifier token should never
273 /// be expanded in the future, due to C99 6.10.3.4p2.
274 bool isExpandDisabled() const { return getFlag(DisableExpand); }
275
276 /// Return true if we have an ObjC keyword identifier.
277 bool isObjCAtKeyword(tok::ObjCKeywordKind objcKey) const;
278
279 /// Return the ObjC keyword kind.
280 tok::ObjCKeywordKind getObjCKeywordID() const;
281
282 /// Return true if this token has trigraphs or escaped newlines in it.
283 bool needsCleaning() const { return getFlag(NeedsCleaning); }
284
285 /// Return true if this token has an empty macro before it.
286 ///
287 bool hasLeadingEmptyMacro() const { return getFlag(LeadingEmptyMacro); }
288
289 /// Return true if this token is a string or character literal which
290 /// has a ud-suffix.
291 bool hasUDSuffix() const { return getFlag(HasUDSuffix); }
292
293 /// Returns true if this token contains a universal character name.
294 bool hasUCN() const { return getFlag(HasUCN); }
295
296 /// Returns true if this token is formed by macro by stringizing or charizing
297 /// operator.
298 bool stringifiedInMacro() const { return getFlag(StringifiedInMacro); }
299
300 /// Returns true if the comma after this token was elided.
301 bool commaAfterElided() const { return getFlag(CommaAfterElided); }
302
303 /// Returns true if this token is an editor placeholder.
304 ///
305 /// Editor placeholders are produced by the code-completion engine and are
306 /// represented as characters between '<#' and '#>' in the source code. The
307 /// lexer uses identifier tokens to represent placeholders.
308 bool isEditorPlaceholder() const { return getFlag(IsEditorPlaceholder); }
309};
310
311/// Information about the conditional stack (\#if directives)
312/// currently active.
313struct PPConditionalInfo {
314 /// Location where the conditional started.
315 SourceLocation IfLoc;
316
317 /// True if this was contained in a skipping directive, e.g.,
318 /// in a "\#if 0" block.
319 bool WasSkipping;
320
321 /// True if we have emitted tokens already, and now we're in
322 /// an \#else block or something. Only useful in Skipping blocks.
323 bool FoundNonSkip;
324
325 /// True if we've seen a \#else in this block. If so,
326 /// \#elif/\#else directives are not allowed.
327 bool FoundElse;
328};
329
330} // end namespace clang
331
332namespace llvm {
333 template <>
334 struct isPodLike<clang::Token> { static const bool value = true; };
335} // end namespace llvm
336
337#endif // LLVM_CLANG_LEX_TOKEN_H
338