Token.h revision 651f13cea278ec967336033dd032faef0e9fc2ec
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_TOKEN_H 15#define LLVM_CLANG_TOKEN_H 16 17#include "clang/Basic/OperatorKinds.h" 18#include "clang/Basic/SourceLocation.h" 19#include "clang/Basic/TemplateKinds.h" 20#include "clang/Basic/TokenKinds.h" 21#include <cstdlib> 22 23namespace clang { 24 25class IdentifierInfo; 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. 38 SourceLocation 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 unsigned 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 /// Other: 61 /// This is null. 62 void *PtrData; 63 64 /// Kind - The actual flavor of token this is. 65 tok::TokenKind Kind; 66 67 /// Flags - Bits we track about this token, members of the TokenFlags enum. 68 unsigned char Flags; 69public: 70 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 }; 84 85 tok::TokenKind getKind() const { return Kind; } 86 void setKind(tok::TokenKind K) { Kind = K; } 87 88 /// is/isNot - Predicates to check if this token is a specific kind, as in 89 /// "if (Tok.is(tok::l_brace)) {...}". 90 bool is(tok::TokenKind K) const { return Kind == K; } 91 bool isNot(tok::TokenKind K) const { return Kind != K; } 92 93 /// \brief Return true if this is a raw identifier (when lexing 94 /// in raw mode) or a non-keyword identifier (when lexing in non-raw mode). 95 bool isAnyIdentifier() const { 96 return tok::isAnyIdentifier(getKind()); 97 } 98 99 /// \brief Return true if this is a "literal", like a numeric 100 /// constant, string, etc. 101 bool isLiteral() const { 102 return tok::isLiteral(getKind()); 103 } 104 105 /// \brief Return true if this is any of tok::annot_* kind tokens. 106 bool isAnnotation() const { 107 return tok::isAnnotation(getKind()); 108 } 109 110 /// \brief Return a source location identifier for the specified 111 /// offset in the current file. 112 SourceLocation getLocation() const { return Loc; } 113 unsigned getLength() const { 114 assert(!isAnnotation() && "Annotation tokens have no length field"); 115 return UintData; 116 } 117 118 void setLocation(SourceLocation L) { Loc = L; } 119 void setLength(unsigned Len) { 120 assert(!isAnnotation() && "Annotation tokens have no length field"); 121 UintData = Len; 122 } 123 124 SourceLocation getAnnotationEndLoc() const { 125 assert(isAnnotation() && "Used AnnotEndLocID on non-annotation token"); 126 return SourceLocation::getFromRawEncoding(UintData); 127 } 128 void setAnnotationEndLoc(SourceLocation L) { 129 assert(isAnnotation() && "Used AnnotEndLocID on non-annotation token"); 130 UintData = L.getRawEncoding(); 131 } 132 133 SourceLocation getLastLoc() const { 134 return isAnnotation() ? getAnnotationEndLoc() : getLocation(); 135 } 136 137 /// \brief SourceRange of the group of tokens that this annotation token 138 /// represents. 139 SourceRange getAnnotationRange() const { 140 return SourceRange(getLocation(), getAnnotationEndLoc()); 141 } 142 void setAnnotationRange(SourceRange R) { 143 setLocation(R.getBegin()); 144 setAnnotationEndLoc(R.getEnd()); 145 } 146 147 const char *getName() const { return tok::getTokenName(Kind); } 148 149 /// \brief Reset all flags to cleared. 150 void startToken() { 151 Kind = tok::unknown; 152 Flags = 0; 153 PtrData = 0; 154 UintData = 0; 155 Loc = SourceLocation(); 156 } 157 158 IdentifierInfo *getIdentifierInfo() const { 159 assert(isNot(tok::raw_identifier) && 160 "getIdentifierInfo() on a tok::raw_identifier token!"); 161 assert(!isAnnotation() && 162 "getIdentifierInfo() on an annotation token!"); 163 if (isLiteral()) return 0; 164 return (IdentifierInfo*) PtrData; 165 } 166 void setIdentifierInfo(IdentifierInfo *II) { 167 PtrData = (void*) II; 168 } 169 170 /// getRawIdentifierData - For a raw identifier token (i.e., an identifier 171 /// lexed in raw mode), returns a pointer to the start of it in the text 172 /// buffer if known, null otherwise. 173 const char *getRawIdentifierData() const { 174 assert(is(tok::raw_identifier)); 175 return reinterpret_cast<const char*>(PtrData); 176 } 177 void setRawIdentifierData(const char *Ptr) { 178 assert(is(tok::raw_identifier)); 179 PtrData = const_cast<char*>(Ptr); 180 } 181 182 /// getLiteralData - For a literal token (numeric constant, string, etc), this 183 /// returns a pointer to the start of it in the text buffer if known, null 184 /// otherwise. 185 const char *getLiteralData() const { 186 assert(isLiteral() && "Cannot get literal data of non-literal"); 187 return reinterpret_cast<const char*>(PtrData); 188 } 189 void setLiteralData(const char *Ptr) { 190 assert(isLiteral() && "Cannot set literal data of non-literal"); 191 PtrData = const_cast<char*>(Ptr); 192 } 193 194 void *getAnnotationValue() const { 195 assert(isAnnotation() && "Used AnnotVal on non-annotation token"); 196 return PtrData; 197 } 198 void setAnnotationValue(void *val) { 199 assert(isAnnotation() && "Used AnnotVal on non-annotation token"); 200 PtrData = val; 201 } 202 203 /// \brief Set the specified flag. 204 void setFlag(TokenFlags Flag) { 205 Flags |= Flag; 206 } 207 208 /// \brief Unset the specified flag. 209 void clearFlag(TokenFlags Flag) { 210 Flags &= ~Flag; 211 } 212 213 /// \brief Return the internal represtation of the flags. 214 /// 215 /// This is only intended for low-level operations such as writing tokens to 216 /// disk. 217 unsigned getFlags() const { 218 return Flags; 219 } 220 221 /// \brief Set a flag to either true or false. 222 void setFlagValue(TokenFlags Flag, bool Val) { 223 if (Val) 224 setFlag(Flag); 225 else 226 clearFlag(Flag); 227 } 228 229 /// isAtStartOfLine - Return true if this token is at the start of a line. 230 /// 231 bool isAtStartOfLine() const { return (Flags & StartOfLine) ? true : false; } 232 233 /// \brief Return true if this token has whitespace before it. 234 /// 235 bool hasLeadingSpace() const { return (Flags & LeadingSpace) ? true : false; } 236 237 /// \brief Return true if this identifier token should never 238 /// be expanded in the future, due to C99 6.10.3.4p2. 239 bool isExpandDisabled() const { 240 return (Flags & DisableExpand) ? true : false; 241 } 242 243 /// \brief Return true if we have an ObjC keyword identifier. 244 bool isObjCAtKeyword(tok::ObjCKeywordKind objcKey) const; 245 246 /// \brief Return the ObjC keyword kind. 247 tok::ObjCKeywordKind getObjCKeywordID() const; 248 249 /// \brief Return true if this token has trigraphs or escaped newlines in it. 250 bool needsCleaning() const { return (Flags & NeedsCleaning) ? true : false; } 251 252 /// \brief Return true if this token has an empty macro before it. 253 /// 254 bool hasLeadingEmptyMacro() const { 255 return (Flags & LeadingEmptyMacro) ? true : false; 256 } 257 258 /// \brief Return true if this token is a string or character literal which 259 /// has a ud-suffix. 260 bool hasUDSuffix() const { return (Flags & HasUDSuffix) ? true : false; } 261 262 /// Returns true if this token contains a universal character name. 263 bool hasUCN() const { return (Flags & HasUCN) ? true : false; } 264}; 265 266/// \brief Information about the conditional stack (\#if directives) 267/// currently active. 268struct PPConditionalInfo { 269 /// \brief Location where the conditional started. 270 SourceLocation IfLoc; 271 272 /// \brief True if this was contained in a skipping directive, e.g., 273 /// in a "\#if 0" block. 274 bool WasSkipping; 275 276 /// \brief True if we have emitted tokens already, and now we're in 277 /// an \#else block or something. Only useful in Skipping blocks. 278 bool FoundNonSkip; 279 280 /// \brief True if we've seen a \#else in this block. If so, 281 /// \#elif/\#else directives are not allowed. 282 bool FoundElse; 283}; 284 285} // end namespace clang 286 287namespace llvm { 288 template <> 289 struct isPodLike<clang::Token> { static const bool value = true; }; 290} // end namespace llvm 291 292#endif 293