token.h revision 85b71799222b55eb5dd74ea26efe0c64ab655c8c
1// Copyright 2011 the V8 project authors. All rights reserved. 2// Redistribution and use in source and binary forms, with or without 3// modification, are permitted provided that the following conditions are 4// met: 5// 6// * Redistributions of source code must retain the above copyright 7// notice, this list of conditions and the following disclaimer. 8// * Redistributions in binary form must reproduce the above 9// copyright notice, this list of conditions and the following 10// disclaimer in the documentation and/or other materials provided 11// with the distribution. 12// * Neither the name of Google Inc. nor the names of its 13// contributors may be used to endorse or promote products derived 14// from this software without specific prior written permission. 15// 16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28#ifndef V8_TOKEN_H_ 29#define V8_TOKEN_H_ 30 31#include "checks.h" 32 33namespace v8 { 34namespace internal { 35 36// TOKEN_LIST takes a list of 3 macros M, all of which satisfy the 37// same signature M(name, string, precedence), where name is the 38// symbolic token name, string is the corresponding syntactic symbol 39// (or NULL, for literals), and precedence is the precedence (or 0). 40// The parameters are invoked for token categories as follows: 41// 42// T: Non-keyword tokens 43// K: Keyword tokens 44 45// IGNORE_TOKEN is a convenience macro that can be supplied as 46// an argument (at any position) for a TOKEN_LIST call. It does 47// nothing with tokens belonging to the respective category. 48 49#define IGNORE_TOKEN(name, string, precedence) 50 51#define TOKEN_LIST(T, K) \ 52 /* End of source indicator. */ \ 53 T(EOS, "EOS", 0) \ 54 \ 55 /* Punctuators (ECMA-262, section 7.7, page 15). */ \ 56 T(LPAREN, "(", 0) \ 57 T(RPAREN, ")", 0) \ 58 T(LBRACK, "[", 0) \ 59 T(RBRACK, "]", 0) \ 60 T(LBRACE, "{", 0) \ 61 T(RBRACE, "}", 0) \ 62 T(COLON, ":", 0) \ 63 T(SEMICOLON, ";", 0) \ 64 T(PERIOD, ".", 0) \ 65 T(CONDITIONAL, "?", 3) \ 66 T(INC, "++", 0) \ 67 T(DEC, "--", 0) \ 68 \ 69 /* Assignment operators. */ \ 70 /* IsAssignmentOp() and Assignment::is_compound() relies on */ \ 71 /* this block of enum values being contiguous and sorted in the */ \ 72 /* same order! */ \ 73 T(INIT_VAR, "=init_var", 2) /* AST-use only. */ \ 74 T(INIT_LET, "=init_let", 2) /* AST-use only. */ \ 75 T(INIT_CONST, "=init_const", 2) /* AST-use only. */ \ 76 T(ASSIGN, "=", 2) \ 77 T(ASSIGN_BIT_OR, "|=", 2) \ 78 T(ASSIGN_BIT_XOR, "^=", 2) \ 79 T(ASSIGN_BIT_AND, "&=", 2) \ 80 T(ASSIGN_SHL, "<<=", 2) \ 81 T(ASSIGN_SAR, ">>=", 2) \ 82 T(ASSIGN_SHR, ">>>=", 2) \ 83 T(ASSIGN_ADD, "+=", 2) \ 84 T(ASSIGN_SUB, "-=", 2) \ 85 T(ASSIGN_MUL, "*=", 2) \ 86 T(ASSIGN_DIV, "/=", 2) \ 87 T(ASSIGN_MOD, "%=", 2) \ 88 \ 89 /* Binary operators sorted by precedence. */ \ 90 /* IsBinaryOp() relies on this block of enum values */ \ 91 /* being contiguous and sorted in the same order! */ \ 92 T(COMMA, ",", 1) \ 93 T(OR, "||", 4) \ 94 T(AND, "&&", 5) \ 95 T(BIT_OR, "|", 6) \ 96 T(BIT_XOR, "^", 7) \ 97 T(BIT_AND, "&", 8) \ 98 T(SHL, "<<", 11) \ 99 T(SAR, ">>", 11) \ 100 T(SHR, ">>>", 11) \ 101 T(ADD, "+", 12) \ 102 T(SUB, "-", 12) \ 103 T(MUL, "*", 13) \ 104 T(DIV, "/", 13) \ 105 T(MOD, "%", 13) \ 106 \ 107 /* Compare operators sorted by precedence. */ \ 108 /* IsCompareOp() relies on this block of enum values */ \ 109 /* being contiguous and sorted in the same order! */ \ 110 T(EQ, "==", 9) \ 111 T(NE, "!=", 9) \ 112 T(EQ_STRICT, "===", 9) \ 113 T(NE_STRICT, "!==", 9) \ 114 T(LT, "<", 10) \ 115 T(GT, ">", 10) \ 116 T(LTE, "<=", 10) \ 117 T(GTE, ">=", 10) \ 118 K(INSTANCEOF, "instanceof", 10) \ 119 K(IN, "in", 10) \ 120 \ 121 /* Unary operators. */ \ 122 /* IsUnaryOp() relies on this block of enum values */ \ 123 /* being contiguous and sorted in the same order! */ \ 124 T(NOT, "!", 0) \ 125 T(BIT_NOT, "~", 0) \ 126 K(DELETE, "delete", 0) \ 127 K(TYPEOF, "typeof", 0) \ 128 K(VOID, "void", 0) \ 129 \ 130 /* Keywords (ECMA-262, section 7.5.2, page 13). */ \ 131 K(BREAK, "break", 0) \ 132 K(CASE, "case", 0) \ 133 K(CATCH, "catch", 0) \ 134 K(CONTINUE, "continue", 0) \ 135 K(DEBUGGER, "debugger", 0) \ 136 K(DEFAULT, "default", 0) \ 137 /* DELETE */ \ 138 K(DO, "do", 0) \ 139 K(ELSE, "else", 0) \ 140 K(FINALLY, "finally", 0) \ 141 K(FOR, "for", 0) \ 142 K(FUNCTION, "function", 0) \ 143 K(IF, "if", 0) \ 144 /* IN */ \ 145 /* INSTANCEOF */ \ 146 K(NEW, "new", 0) \ 147 K(RETURN, "return", 0) \ 148 K(SWITCH, "switch", 0) \ 149 K(THIS, "this", 0) \ 150 K(THROW, "throw", 0) \ 151 K(TRY, "try", 0) \ 152 /* TYPEOF */ \ 153 K(VAR, "var", 0) \ 154 /* VOID */ \ 155 K(WHILE, "while", 0) \ 156 K(WITH, "with", 0) \ 157 \ 158 /* Literals (ECMA-262, section 7.8, page 16). */ \ 159 K(NULL_LITERAL, "null", 0) \ 160 K(TRUE_LITERAL, "true", 0) \ 161 K(FALSE_LITERAL, "false", 0) \ 162 T(NUMBER, NULL, 0) \ 163 T(STRING, NULL, 0) \ 164 \ 165 /* Identifiers (not keywords or future reserved words). */ \ 166 T(IDENTIFIER, NULL, 0) \ 167 \ 168 /* Future reserved words (ECMA-262, section 7.6.1.2). */ \ 169 T(FUTURE_RESERVED_WORD, NULL, 0) \ 170 T(FUTURE_STRICT_RESERVED_WORD, NULL, 0) \ 171 K(CONST, "const", 0) \ 172 K(LET, "let", 0) \ 173 \ 174 /* Illegal token - not able to scan. */ \ 175 T(ILLEGAL, "ILLEGAL", 0) \ 176 \ 177 /* Scanner-internal use only. */ \ 178 T(WHITESPACE, NULL, 0) 179 180 181class Token { 182 public: 183 // All token values. 184#define T(name, string, precedence) name, 185 enum Value { 186 TOKEN_LIST(T, T) 187 NUM_TOKENS 188 }; 189#undef T 190 191 // Returns a string corresponding to the C++ token name 192 // (e.g. "LT" for the token LT). 193 static const char* Name(Value tok) { 194 ASSERT(tok < NUM_TOKENS); // tok is unsigned 195 return name_[tok]; 196 } 197 198 // Predicates 199 static bool IsKeyword(Value tok) { 200 return token_type[tok] == 'K'; 201 } 202 203 static bool IsAssignmentOp(Value tok) { 204 return INIT_VAR <= tok && tok <= ASSIGN_MOD; 205 } 206 207 static bool IsBinaryOp(Value op) { 208 return COMMA <= op && op <= MOD; 209 } 210 211 static bool IsCompareOp(Value op) { 212 return EQ <= op && op <= IN; 213 } 214 215 static bool IsOrderedCompareOp(Value op) { 216 return op == LT || op == LTE || op == GT || op == GTE; 217 } 218 219 static Value NegateCompareOp(Value op) { 220 ASSERT(IsCompareOp(op)); 221 switch (op) { 222 case EQ: return NE; 223 case NE: return EQ; 224 case EQ_STRICT: return NE_STRICT; 225 case LT: return GTE; 226 case GT: return LTE; 227 case LTE: return GT; 228 case GTE: return LT; 229 default: 230 return op; 231 } 232 } 233 234 static Value InvertCompareOp(Value op) { 235 ASSERT(IsCompareOp(op)); 236 switch (op) { 237 case EQ: return NE; 238 case NE: return EQ; 239 case EQ_STRICT: return NE_STRICT; 240 case LT: return GT; 241 case GT: return LT; 242 case LTE: return GTE; 243 case GTE: return LTE; 244 default: 245 return op; 246 } 247 } 248 249 static bool IsBitOp(Value op) { 250 return (BIT_OR <= op && op <= SHR) || op == BIT_NOT; 251 } 252 253 static bool IsUnaryOp(Value op) { 254 return (NOT <= op && op <= VOID) || op == ADD || op == SUB; 255 } 256 257 static bool IsCountOp(Value op) { 258 return op == INC || op == DEC; 259 } 260 261 static bool IsShiftOp(Value op) { 262 return (SHL <= op) && (op <= SHR); 263 } 264 265 // Returns a string corresponding to the JS token string 266 // (.e., "<" for the token LT) or NULL if the token doesn't 267 // have a (unique) string (e.g. an IDENTIFIER). 268 static const char* String(Value tok) { 269 ASSERT(tok < NUM_TOKENS); // tok is unsigned. 270 return string_[tok]; 271 } 272 273 // Returns the precedence > 0 for binary and compare 274 // operators; returns 0 otherwise. 275 static int Precedence(Value tok) { 276 ASSERT(tok < NUM_TOKENS); // tok is unsigned. 277 return precedence_[tok]; 278 } 279 280 private: 281 static const char* const name_[NUM_TOKENS]; 282 static const char* const string_[NUM_TOKENS]; 283 static const int8_t precedence_[NUM_TOKENS]; 284 static const char token_type[NUM_TOKENS]; 285}; 286 287} } // namespace v8::internal 288 289#endif // V8_TOKEN_H_ 290