1 // Copyright 2012 the V8 project authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef V8_PARSING_TOKEN_H_ 6 #define V8_PARSING_TOKEN_H_ 7 8 #include "src/base/logging.h" 9 #include "src/globals.h" 10 11 namespace v8 { 12 namespace internal { 13 14 // TOKEN_LIST takes a list of 3 macros M, all of which satisfy the 15 // same signature M(name, string, precedence), where name is the 16 // symbolic token name, string is the corresponding syntactic symbol 17 // (or NULL, for literals), and precedence is the precedence (or 0). 18 // The parameters are invoked for token categories as follows: 19 // 20 // T: Non-keyword tokens 21 // K: Keyword tokens 22 23 // IGNORE_TOKEN is a convenience macro that can be supplied as 24 // an argument (at any position) for a TOKEN_LIST call. It does 25 // nothing with tokens belonging to the respective category. 26 27 #define IGNORE_TOKEN(name, string, precedence) 28 29 #define TOKEN_LIST(T, K) \ 30 /* End of source indicator. */ \ 31 T(EOS, "EOS", 0) \ 32 \ 33 /* Punctuators (ECMA-262, section 7.7, page 15). */ \ 34 T(LPAREN, "(", 0) \ 35 T(RPAREN, ")", 0) \ 36 T(LBRACK, "[", 0) \ 37 T(RBRACK, "]", 0) \ 38 T(LBRACE, "{", 0) \ 39 T(RBRACE, "}", 0) \ 40 T(COLON, ":", 0) \ 41 T(SEMICOLON, ";", 0) \ 42 T(PERIOD, ".", 0) \ 43 T(ELLIPSIS, "...", 0) \ 44 T(CONDITIONAL, "?", 3) \ 45 T(INC, "++", 0) \ 46 T(DEC, "--", 0) \ 47 T(ARROW, "=>", 0) \ 48 \ 49 /* Assignment operators. */ \ 50 /* IsAssignmentOp() and Assignment::is_compound() relies on */ \ 51 /* this block of enum values being contiguous and sorted in the */ \ 52 /* same order! */ \ 53 T(INIT, "=init", 2) /* AST-use only. */ \ 54 T(ASSIGN, "=", 2) \ 55 T(ASSIGN_BIT_OR, "|=", 2) \ 56 T(ASSIGN_BIT_XOR, "^=", 2) \ 57 T(ASSIGN_BIT_AND, "&=", 2) \ 58 T(ASSIGN_SHL, "<<=", 2) \ 59 T(ASSIGN_SAR, ">>=", 2) \ 60 T(ASSIGN_SHR, ">>>=", 2) \ 61 T(ASSIGN_ADD, "+=", 2) \ 62 T(ASSIGN_SUB, "-=", 2) \ 63 T(ASSIGN_MUL, "*=", 2) \ 64 T(ASSIGN_DIV, "/=", 2) \ 65 T(ASSIGN_MOD, "%=", 2) \ 66 \ 67 /* Binary operators sorted by precedence. */ \ 68 /* IsBinaryOp() relies on this block of enum values */ \ 69 /* being contiguous and sorted in the same order! */ \ 70 T(COMMA, ",", 1) \ 71 T(OR, "||", 4) \ 72 T(AND, "&&", 5) \ 73 T(BIT_OR, "|", 6) \ 74 T(BIT_XOR, "^", 7) \ 75 T(BIT_AND, "&", 8) \ 76 T(SHL, "<<", 11) \ 77 T(SAR, ">>", 11) \ 78 T(SHR, ">>>", 11) \ 79 T(ROR, "rotate right", 11) /* only used by Crankshaft */ \ 80 T(ADD, "+", 12) \ 81 T(SUB, "-", 12) \ 82 T(MUL, "*", 13) \ 83 T(DIV, "/", 13) \ 84 T(MOD, "%", 13) \ 85 \ 86 /* Compare operators sorted by precedence. */ \ 87 /* IsCompareOp() relies on this block of enum values */ \ 88 /* being contiguous and sorted in the same order! */ \ 89 T(EQ, "==", 9) \ 90 T(NE, "!=", 9) \ 91 T(EQ_STRICT, "===", 9) \ 92 T(NE_STRICT, "!==", 9) \ 93 T(LT, "<", 10) \ 94 T(GT, ">", 10) \ 95 T(LTE, "<=", 10) \ 96 T(GTE, ">=", 10) \ 97 K(INSTANCEOF, "instanceof", 10) \ 98 K(IN, "in", 10) \ 99 \ 100 /* Unary operators. */ \ 101 /* IsUnaryOp() relies on this block of enum values */ \ 102 /* being contiguous and sorted in the same order! */ \ 103 T(NOT, "!", 0) \ 104 T(BIT_NOT, "~", 0) \ 105 K(DELETE, "delete", 0) \ 106 K(TYPEOF, "typeof", 0) \ 107 K(VOID, "void", 0) \ 108 \ 109 /* Keywords (ECMA-262, section 7.5.2, page 13). */ \ 110 K(BREAK, "break", 0) \ 111 K(CASE, "case", 0) \ 112 K(CATCH, "catch", 0) \ 113 K(CONTINUE, "continue", 0) \ 114 K(DEBUGGER, "debugger", 0) \ 115 K(DEFAULT, "default", 0) \ 116 /* DELETE */ \ 117 K(DO, "do", 0) \ 118 K(ELSE, "else", 0) \ 119 K(FINALLY, "finally", 0) \ 120 K(FOR, "for", 0) \ 121 K(FUNCTION, "function", 0) \ 122 K(IF, "if", 0) \ 123 /* IN */ \ 124 /* INSTANCEOF */ \ 125 K(NEW, "new", 0) \ 126 K(RETURN, "return", 0) \ 127 K(SWITCH, "switch", 0) \ 128 K(THIS, "this", 0) \ 129 K(THROW, "throw", 0) \ 130 K(TRY, "try", 0) \ 131 /* TYPEOF */ \ 132 K(VAR, "var", 0) \ 133 /* VOID */ \ 134 K(WHILE, "while", 0) \ 135 K(WITH, "with", 0) \ 136 \ 137 /* Literals (ECMA-262, section 7.8, page 16). */ \ 138 K(NULL_LITERAL, "null", 0) \ 139 K(TRUE_LITERAL, "true", 0) \ 140 K(FALSE_LITERAL, "false", 0) \ 141 T(NUMBER, NULL, 0) \ 142 T(SMI, NULL, 0) \ 143 T(STRING, NULL, 0) \ 144 \ 145 /* Identifiers (not keywords or future reserved words). */ \ 146 T(IDENTIFIER, NULL, 0) \ 147 \ 148 /* Future reserved words (ECMA-262, section 7.6.1.2). */ \ 149 T(FUTURE_RESERVED_WORD, NULL, 0) \ 150 T(FUTURE_STRICT_RESERVED_WORD, NULL, 0) \ 151 K(CLASS, "class", 0) \ 152 K(CONST, "const", 0) \ 153 K(EXPORT, "export", 0) \ 154 K(EXTENDS, "extends", 0) \ 155 K(IMPORT, "import", 0) \ 156 K(LET, "let", 0) \ 157 K(STATIC, "static", 0) \ 158 K(YIELD, "yield", 0) \ 159 K(SUPER, "super", 0) \ 160 \ 161 /* Illegal token - not able to scan. */ \ 162 T(ILLEGAL, "ILLEGAL", 0) \ 163 T(ESCAPED_KEYWORD, NULL, 0) \ 164 T(ESCAPED_STRICT_RESERVED_WORD, NULL, 0) \ 165 \ 166 /* Scanner-internal use only. */ \ 167 T(WHITESPACE, NULL, 0) \ 168 T(UNINITIALIZED, NULL, 0) \ 169 \ 170 /* ES6 Template Literals */ \ 171 T(TEMPLATE_SPAN, NULL, 0) \ 172 T(TEMPLATE_TAIL, NULL, 0) 173 174 175 class Token { 176 public: 177 // All token values. 178 #define T(name, string, precedence) name, 179 enum Value { 180 TOKEN_LIST(T, T) 181 NUM_TOKENS 182 }; 183 #undef T 184 185 // Returns a string corresponding to the C++ token name 186 // (e.g. "LT" for the token LT). Name(Value tok)187 static const char* Name(Value tok) { 188 DCHECK(tok < NUM_TOKENS); // tok is unsigned 189 return name_[tok]; 190 } 191 192 // Predicates IsKeyword(Value tok)193 static bool IsKeyword(Value tok) { 194 return token_type[tok] == 'K'; 195 } 196 IsIdentifier(Value tok,LanguageMode language_mode,bool is_generator)197 static bool IsIdentifier(Value tok, LanguageMode language_mode, 198 bool is_generator) { 199 switch (tok) { 200 case IDENTIFIER: 201 return true; 202 case ESCAPED_STRICT_RESERVED_WORD: 203 case FUTURE_STRICT_RESERVED_WORD: 204 case LET: 205 case STATIC: 206 return is_sloppy(language_mode); 207 case YIELD: 208 return !is_generator && is_sloppy(language_mode); 209 default: 210 return false; 211 } 212 UNREACHABLE(); 213 return false; 214 } 215 IsAssignmentOp(Value tok)216 static bool IsAssignmentOp(Value tok) { 217 return INIT <= tok && tok <= ASSIGN_MOD; 218 } 219 IsBinaryOp(Value op)220 static bool IsBinaryOp(Value op) { 221 return COMMA <= op && op <= MOD; 222 } 223 IsTruncatingBinaryOp(Value op)224 static bool IsTruncatingBinaryOp(Value op) { 225 return BIT_OR <= op && op <= ROR; 226 } 227 IsCompareOp(Value op)228 static bool IsCompareOp(Value op) { 229 return EQ <= op && op <= IN; 230 } 231 IsOrderedRelationalCompareOp(Value op)232 static bool IsOrderedRelationalCompareOp(Value op) { 233 return op == LT || op == LTE || op == GT || op == GTE; 234 } 235 IsEqualityOp(Value op)236 static bool IsEqualityOp(Value op) { 237 return op == EQ || op == EQ_STRICT; 238 } 239 IsInequalityOp(Value op)240 static bool IsInequalityOp(Value op) { 241 return op == NE || op == NE_STRICT; 242 } 243 IsArithmeticCompareOp(Value op)244 static bool IsArithmeticCompareOp(Value op) { 245 return IsOrderedRelationalCompareOp(op) || 246 IsEqualityOp(op) || IsInequalityOp(op); 247 } 248 NegateCompareOp(Value op)249 static Value NegateCompareOp(Value op) { 250 DCHECK(IsArithmeticCompareOp(op)); 251 switch (op) { 252 case EQ: return NE; 253 case NE: return EQ; 254 case EQ_STRICT: return NE_STRICT; 255 case NE_STRICT: return EQ_STRICT; 256 case LT: return GTE; 257 case GT: return LTE; 258 case LTE: return GT; 259 case GTE: return LT; 260 default: 261 UNREACHABLE(); 262 return op; 263 } 264 } 265 ReverseCompareOp(Value op)266 static Value ReverseCompareOp(Value op) { 267 DCHECK(IsArithmeticCompareOp(op)); 268 switch (op) { 269 case EQ: return EQ; 270 case NE: return NE; 271 case EQ_STRICT: return EQ_STRICT; 272 case NE_STRICT: return NE_STRICT; 273 case LT: return GT; 274 case GT: return LT; 275 case LTE: return GTE; 276 case GTE: return LTE; 277 default: 278 UNREACHABLE(); 279 return op; 280 } 281 } 282 IsBitOp(Value op)283 static bool IsBitOp(Value op) { 284 return (BIT_OR <= op && op <= SHR) || op == BIT_NOT; 285 } 286 IsUnaryOp(Value op)287 static bool IsUnaryOp(Value op) { 288 return (NOT <= op && op <= VOID) || op == ADD || op == SUB; 289 } 290 IsCountOp(Value op)291 static bool IsCountOp(Value op) { 292 return op == INC || op == DEC; 293 } 294 IsShiftOp(Value op)295 static bool IsShiftOp(Value op) { 296 return (SHL <= op) && (op <= SHR); 297 } 298 299 // Returns a string corresponding to the JS token string 300 // (.e., "<" for the token LT) or NULL if the token doesn't 301 // have a (unique) string (e.g. an IDENTIFIER). String(Value tok)302 static const char* String(Value tok) { 303 DCHECK(tok < NUM_TOKENS); // tok is unsigned. 304 return string_[tok]; 305 } 306 307 // Returns the precedence > 0 for binary and compare 308 // operators; returns 0 otherwise. Precedence(Value tok)309 static int Precedence(Value tok) { 310 DCHECK(tok < NUM_TOKENS); // tok is unsigned. 311 return precedence_[tok]; 312 } 313 314 private: 315 static const char* const name_[NUM_TOKENS]; 316 static const char* const string_[NUM_TOKENS]; 317 static const int8_t precedence_[NUM_TOKENS]; 318 static const char token_type[NUM_TOKENS]; 319 }; 320 321 } // namespace internal 322 } // namespace v8 323 324 #endif // V8_PARSING_TOKEN_H_ 325