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 "llvm/ADT/StringRef.h" 22 #include <cstdlib> 23 24 namespace clang { 25 26 class IdentifierInfo; 27 28 /// Token - This structure provides full information about a lexed token. 29 /// It is not intended to be space efficient, it is intended to return as much 30 /// information as possible about each returned token. This is expected to be 31 /// compressed into a smaller form if memory footprint is important. 32 /// 33 /// The parser can create a special "annotation token" representing a stream of 34 /// tokens that were parsed and semantically resolved, e.g.: "foo::MyClass<int>" 35 /// can be represented by a single typename annotation token that carries 36 /// information about the SourceRange of the tokens and the type object. 37 class Token { 38 /// The location of the token. 39 SourceLocation Loc; 40 41 // Conceptually these next two fields could be in a union. However, this 42 // causes gcc 4.2 to pessimize LexTokenInternal, a very performance critical 43 // routine. Keeping as separate members with casts until a more beautiful fix 44 // presents itself. 45 46 /// UintData - This holds either the length of the token text, when 47 /// a normal token, or the end of the SourceRange when an annotation 48 /// token. 49 unsigned UintData; 50 51 /// PtrData - This is a union of four different pointer types, which depends 52 /// on what type of token this is: 53 /// Identifiers, keywords, etc: 54 /// This is an IdentifierInfo*, which contains the uniqued identifier 55 /// spelling. 56 /// Literals: isLiteral() returns true. 57 /// This is a pointer to the start of the token in a text buffer, which 58 /// may be dirty (have trigraphs / escaped newlines). 59 /// Annotations (resolved type names, C++ scopes, etc): isAnnotation(). 60 /// This is a pointer to sema-specific data for the annotation token. 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 char Flags; 70 public: 71 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 }; 85 getKind()86 tok::TokenKind getKind() const { return Kind; } setKind(tok::TokenKind K)87 void setKind(tok::TokenKind K) { Kind = K; } 88 89 /// is/isNot - Predicates to check if this token is a specific kind, as in 90 /// "if (Tok.is(tok::l_brace)) {...}". is(tok::TokenKind K)91 bool is(tok::TokenKind K) const { return Kind == K; } isNot(tok::TokenKind K)92 bool isNot(tok::TokenKind K) const { return Kind != K; } 93 94 /// \brief Return true if this is a raw identifier (when lexing 95 /// in raw mode) or a non-keyword identifier (when lexing in non-raw mode). isAnyIdentifier()96 bool isAnyIdentifier() const { 97 return tok::isAnyIdentifier(getKind()); 98 } 99 100 /// \brief Return true if this is a "literal", like a numeric 101 /// constant, string, etc. isLiteral()102 bool isLiteral() const { 103 return tok::isLiteral(getKind()); 104 } 105 106 /// \brief Return true if this is any of tok::annot_* kind tokens. isAnnotation()107 bool isAnnotation() const { 108 return tok::isAnnotation(getKind()); 109 } 110 111 /// \brief Return a source location identifier for the specified 112 /// offset in the current file. getLocation()113 SourceLocation getLocation() const { return Loc; } getLength()114 unsigned getLength() const { 115 assert(!isAnnotation() && "Annotation tokens have no length field"); 116 return UintData; 117 } 118 setLocation(SourceLocation L)119 void setLocation(SourceLocation L) { Loc = L; } setLength(unsigned Len)120 void setLength(unsigned Len) { 121 assert(!isAnnotation() && "Annotation tokens have no length field"); 122 UintData = Len; 123 } 124 getAnnotationEndLoc()125 SourceLocation getAnnotationEndLoc() const { 126 assert(isAnnotation() && "Used AnnotEndLocID on non-annotation token"); 127 return SourceLocation::getFromRawEncoding(UintData); 128 } setAnnotationEndLoc(SourceLocation L)129 void setAnnotationEndLoc(SourceLocation L) { 130 assert(isAnnotation() && "Used AnnotEndLocID on non-annotation token"); 131 UintData = L.getRawEncoding(); 132 } 133 getLastLoc()134 SourceLocation getLastLoc() const { 135 return isAnnotation() ? getAnnotationEndLoc() : getLocation(); 136 } 137 138 /// \brief SourceRange of the group of tokens that this annotation token 139 /// represents. getAnnotationRange()140 SourceRange getAnnotationRange() const { 141 return SourceRange(getLocation(), getAnnotationEndLoc()); 142 } setAnnotationRange(SourceRange R)143 void setAnnotationRange(SourceRange R) { 144 setLocation(R.getBegin()); 145 setAnnotationEndLoc(R.getEnd()); 146 } 147 getName()148 const char *getName() const { return tok::getTokenName(Kind); } 149 150 /// \brief Reset all flags to cleared. startToken()151 void startToken() { 152 Kind = tok::unknown; 153 Flags = 0; 154 PtrData = nullptr; 155 UintData = 0; 156 Loc = SourceLocation(); 157 } 158 getIdentifierInfo()159 IdentifierInfo *getIdentifierInfo() const { 160 assert(isNot(tok::raw_identifier) && 161 "getIdentifierInfo() on a tok::raw_identifier token!"); 162 assert(!isAnnotation() && 163 "getIdentifierInfo() on an annotation token!"); 164 if (isLiteral()) return nullptr; 165 return (IdentifierInfo*) PtrData; 166 } setIdentifierInfo(IdentifierInfo * II)167 void setIdentifierInfo(IdentifierInfo *II) { 168 PtrData = (void*) II; 169 } 170 171 /// getRawIdentifier - For a raw identifier token (i.e., an identifier 172 /// lexed in raw mode), returns a reference to the text substring in the 173 /// buffer if known. getRawIdentifier()174 StringRef getRawIdentifier() const { 175 assert(is(tok::raw_identifier)); 176 return StringRef(reinterpret_cast<const char *>(PtrData), getLength()); 177 } setRawIdentifierData(const char * Ptr)178 void setRawIdentifierData(const char *Ptr) { 179 assert(is(tok::raw_identifier)); 180 PtrData = const_cast<char*>(Ptr); 181 } 182 183 /// getLiteralData - For a literal token (numeric constant, string, etc), this 184 /// returns a pointer to the start of it in the text buffer if known, null 185 /// otherwise. getLiteralData()186 const char *getLiteralData() const { 187 assert(isLiteral() && "Cannot get literal data of non-literal"); 188 return reinterpret_cast<const char*>(PtrData); 189 } setLiteralData(const char * Ptr)190 void setLiteralData(const char *Ptr) { 191 assert(isLiteral() && "Cannot set literal data of non-literal"); 192 PtrData = const_cast<char*>(Ptr); 193 } 194 getAnnotationValue()195 void *getAnnotationValue() const { 196 assert(isAnnotation() && "Used AnnotVal on non-annotation token"); 197 return PtrData; 198 } setAnnotationValue(void * val)199 void setAnnotationValue(void *val) { 200 assert(isAnnotation() && "Used AnnotVal on non-annotation token"); 201 PtrData = val; 202 } 203 204 /// \brief Set the specified flag. setFlag(TokenFlags Flag)205 void setFlag(TokenFlags Flag) { 206 Flags |= Flag; 207 } 208 209 /// \brief Unset the specified flag. clearFlag(TokenFlags Flag)210 void clearFlag(TokenFlags Flag) { 211 Flags &= ~Flag; 212 } 213 214 /// \brief Return the internal represtation of the flags. 215 /// 216 /// This is only intended for low-level operations such as writing tokens to 217 /// disk. getFlags()218 unsigned getFlags() const { 219 return Flags; 220 } 221 222 /// \brief Set a flag to either true or false. setFlagValue(TokenFlags Flag,bool Val)223 void setFlagValue(TokenFlags Flag, bool Val) { 224 if (Val) 225 setFlag(Flag); 226 else 227 clearFlag(Flag); 228 } 229 230 /// isAtStartOfLine - Return true if this token is at the start of a line. 231 /// isAtStartOfLine()232 bool isAtStartOfLine() const { return (Flags & StartOfLine) ? true : false; } 233 234 /// \brief Return true if this token has whitespace before it. 235 /// hasLeadingSpace()236 bool hasLeadingSpace() const { return (Flags & LeadingSpace) ? true : false; } 237 238 /// \brief Return true if this identifier token should never 239 /// be expanded in the future, due to C99 6.10.3.4p2. isExpandDisabled()240 bool isExpandDisabled() const { 241 return (Flags & DisableExpand) ? true : false; 242 } 243 244 /// \brief Return true if we have an ObjC keyword identifier. 245 bool isObjCAtKeyword(tok::ObjCKeywordKind objcKey) const; 246 247 /// \brief Return the ObjC keyword kind. 248 tok::ObjCKeywordKind getObjCKeywordID() const; 249 250 /// \brief Return true if this token has trigraphs or escaped newlines in it. needsCleaning()251 bool needsCleaning() const { return (Flags & NeedsCleaning) ? true : false; } 252 253 /// \brief Return true if this token has an empty macro before it. 254 /// hasLeadingEmptyMacro()255 bool hasLeadingEmptyMacro() const { 256 return (Flags & LeadingEmptyMacro) ? true : false; 257 } 258 259 /// \brief Return true if this token is a string or character literal which 260 /// has a ud-suffix. hasUDSuffix()261 bool hasUDSuffix() const { return (Flags & HasUDSuffix) ? true : false; } 262 263 /// Returns true if this token contains a universal character name. hasUCN()264 bool hasUCN() const { return (Flags & HasUCN) ? true : false; } 265 }; 266 267 /// \brief Information about the conditional stack (\#if directives) 268 /// currently active. 269 struct PPConditionalInfo { 270 /// \brief Location where the conditional started. 271 SourceLocation IfLoc; 272 273 /// \brief True if this was contained in a skipping directive, e.g., 274 /// in a "\#if 0" block. 275 bool WasSkipping; 276 277 /// \brief True if we have emitted tokens already, and now we're in 278 /// an \#else block or something. Only useful in Skipping blocks. 279 bool FoundNonSkip; 280 281 /// \brief True if we've seen a \#else in this block. If so, 282 /// \#elif/\#else directives are not allowed. 283 bool FoundElse; 284 }; 285 286 } // end namespace clang 287 288 namespace llvm { 289 template <> 290 struct isPodLike<clang::Token> { static const bool value = true; }; 291 } // end namespace llvm 292 293 #endif 294