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_TOKEN_H_
6#define V8_TOKEN_H_
7
8#include "src/base/logging.h"
9
10namespace v8 {
11namespace internal {
12
13// TOKEN_LIST takes a list of 3 macros M, all of which satisfy the
14// same signature M(name, string, precedence), where name is the
15// symbolic token name, string is the corresponding syntactic symbol
16// (or NULL, for literals), and precedence is the precedence (or 0).
17// The parameters are invoked for token categories as follows:
18//
19//   T: Non-keyword tokens
20//   K: Keyword tokens
21
22// IGNORE_TOKEN is a convenience macro that can be supplied as
23// an argument (at any position) for a TOKEN_LIST call. It does
24// nothing with tokens belonging to the respective category.
25
26#define IGNORE_TOKEN(name, string, precedence)
27
28#define TOKEN_LIST(T, K)                                             \
29  /* End of source indicator. */                                     \
30  T(EOS, "EOS", 0)                                                   \
31                                                                     \
32  /* Punctuators (ECMA-262, section 7.7, page 15). */                \
33  T(LPAREN, "(", 0)                                                  \
34  T(RPAREN, ")", 0)                                                  \
35  T(LBRACK, "[", 0)                                                  \
36  T(RBRACK, "]", 0)                                                  \
37  T(LBRACE, "{", 0)                                                  \
38  T(RBRACE, "}", 0)                                                  \
39  T(COLON, ":", 0)                                                   \
40  T(SEMICOLON, ";", 0)                                               \
41  T(PERIOD, ".", 0)                                                  \
42  T(CONDITIONAL, "?", 3)                                             \
43  T(INC, "++", 0)                                                    \
44  T(DEC, "--", 0)                                                    \
45  T(ARROW, "=>", 0)                                                  \
46                                                                     \
47  /* Assignment operators. */                                        \
48  /* IsAssignmentOp() and Assignment::is_compound() relies on */     \
49  /* this block of enum values being contiguous and sorted in the */ \
50  /* same order! */                                                  \
51  T(INIT_VAR, "=init_var", 2)                   /* AST-use only. */  \
52  T(INIT_LET, "=init_let", 2)                   /* AST-use only. */  \
53  T(INIT_CONST, "=init_const", 2)               /* AST-use only. */  \
54  T(INIT_CONST_LEGACY, "=init_const_legacy", 2) /* AST-use only. */  \
55  T(ASSIGN, "=", 2)                                                  \
56  T(ASSIGN_BIT_OR, "|=", 2)                                          \
57  T(ASSIGN_BIT_XOR, "^=", 2)                                         \
58  T(ASSIGN_BIT_AND, "&=", 2)                                         \
59  T(ASSIGN_SHL, "<<=", 2)                                            \
60  T(ASSIGN_SAR, ">>=", 2)                                            \
61  T(ASSIGN_SHR, ">>>=", 2)                                           \
62  T(ASSIGN_ADD, "+=", 2)                                             \
63  T(ASSIGN_SUB, "-=", 2)                                             \
64  T(ASSIGN_MUL, "*=", 2)                                             \
65  T(ASSIGN_DIV, "/=", 2)                                             \
66  T(ASSIGN_MOD, "%=", 2)                                             \
67                                                                     \
68  /* Binary operators sorted by precedence. */                       \
69  /* IsBinaryOp() relies on this block of enum values */             \
70  /* being contiguous and sorted in the same order! */               \
71  T(COMMA, ",", 1)                                                   \
72  T(OR, "||", 4)                                                     \
73  T(AND, "&&", 5)                                                    \
74  T(BIT_OR, "|", 6)                                                  \
75  T(BIT_XOR, "^", 7)                                                 \
76  T(BIT_AND, "&", 8)                                                 \
77  T(SHL, "<<", 11)                                                   \
78  T(SAR, ">>", 11)                                                   \
79  T(SHR, ">>>", 11)                                                  \
80  T(ROR, "rotate right", 11) /* only used by Crankshaft */           \
81  T(ADD, "+", 12)                                                    \
82  T(SUB, "-", 12)                                                    \
83  T(MUL, "*", 13)                                                    \
84  T(DIV, "/", 13)                                                    \
85  T(MOD, "%", 13)                                                    \
86                                                                     \
87  /* Compare operators sorted by precedence. */                      \
88  /* IsCompareOp() relies on this block of enum values */            \
89  /* being contiguous and sorted in the same order! */               \
90  T(EQ, "==", 9)                                                     \
91  T(NE, "!=", 9)                                                     \
92  T(EQ_STRICT, "===", 9)                                             \
93  T(NE_STRICT, "!==", 9)                                             \
94  T(LT, "<", 10)                                                     \
95  T(GT, ">", 10)                                                     \
96  T(LTE, "<=", 10)                                                   \
97  T(GTE, ">=", 10)                                                   \
98  K(INSTANCEOF, "instanceof", 10)                                    \
99  K(IN, "in", 10)                                                    \
100                                                                     \
101  /* Unary operators. */                                             \
102  /* IsUnaryOp() relies on this block of enum values */              \
103  /* being contiguous and sorted in the same order! */               \
104  T(NOT, "!", 0)                                                     \
105  T(BIT_NOT, "~", 0)                                                 \
106  K(DELETE, "delete", 0)                                             \
107  K(TYPEOF, "typeof", 0)                                             \
108  K(VOID, "void", 0)                                                 \
109                                                                     \
110  /* Keywords (ECMA-262, section 7.5.2, page 13). */                 \
111  K(BREAK, "break", 0)                                               \
112  K(CASE, "case", 0)                                                 \
113  K(CATCH, "catch", 0)                                               \
114  K(CONTINUE, "continue", 0)                                         \
115  K(DEBUGGER, "debugger", 0)                                         \
116  K(DEFAULT, "default", 0)                                           \
117  /* DELETE */                                                       \
118  K(DO, "do", 0)                                                     \
119  K(ELSE, "else", 0)                                                 \
120  K(FINALLY, "finally", 0)                                           \
121  K(FOR, "for", 0)                                                   \
122  K(FUNCTION, "function", 0)                                         \
123  K(IF, "if", 0)                                                     \
124  /* IN */                                                           \
125  /* INSTANCEOF */                                                   \
126  K(NEW, "new", 0)                                                   \
127  K(RETURN, "return", 0)                                             \
128  K(SWITCH, "switch", 0)                                             \
129  K(THIS, "this", 0)                                                 \
130  K(THROW, "throw", 0)                                               \
131  K(TRY, "try", 0)                                                   \
132  /* TYPEOF */                                                       \
133  K(VAR, "var", 0)                                                   \
134  /* VOID */                                                         \
135  K(WHILE, "while", 0)                                               \
136  K(WITH, "with", 0)                                                 \
137                                                                     \
138  /* Literals (ECMA-262, section 7.8, page 16). */                   \
139  K(NULL_LITERAL, "null", 0)                                         \
140  K(TRUE_LITERAL, "true", 0)                                         \
141  K(FALSE_LITERAL, "false", 0)                                       \
142  T(NUMBER, 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                                                                     \
164  /* Scanner-internal use only. */                                   \
165  T(WHITESPACE, NULL, 0)
166
167
168class Token {
169 public:
170  // All token values.
171#define T(name, string, precedence) name,
172  enum Value {
173    TOKEN_LIST(T, T)
174    NUM_TOKENS
175  };
176#undef T
177
178  // Returns a string corresponding to the C++ token name
179  // (e.g. "LT" for the token LT).
180  static const char* Name(Value tok) {
181    DCHECK(tok < NUM_TOKENS);  // tok is unsigned
182    return name_[tok];
183  }
184
185  // Predicates
186  static bool IsKeyword(Value tok) {
187    return token_type[tok] == 'K';
188  }
189
190  static bool IsAssignmentOp(Value tok) {
191    return INIT_VAR <= tok && tok <= ASSIGN_MOD;
192  }
193
194  static bool IsBinaryOp(Value op) {
195    return COMMA <= op && op <= MOD;
196  }
197
198  static bool IsTruncatingBinaryOp(Value op) {
199    return BIT_OR <= op && op <= ROR;
200  }
201
202  static bool IsCompareOp(Value op) {
203    return EQ <= op && op <= IN;
204  }
205
206  static bool IsOrderedRelationalCompareOp(Value op) {
207    return op == LT || op == LTE || op == GT || op == GTE;
208  }
209
210  static bool IsEqualityOp(Value op) {
211    return op == EQ || op == EQ_STRICT;
212  }
213
214  static bool IsInequalityOp(Value op) {
215    return op == NE || op == NE_STRICT;
216  }
217
218  static bool IsArithmeticCompareOp(Value op) {
219    return IsOrderedRelationalCompareOp(op) ||
220        IsEqualityOp(op) || IsInequalityOp(op);
221  }
222
223  static Value NegateCompareOp(Value op) {
224    DCHECK(IsArithmeticCompareOp(op));
225    switch (op) {
226      case EQ: return NE;
227      case NE: return EQ;
228      case EQ_STRICT: return NE_STRICT;
229      case NE_STRICT: return EQ_STRICT;
230      case LT: return GTE;
231      case GT: return LTE;
232      case LTE: return GT;
233      case GTE: return LT;
234      default:
235        UNREACHABLE();
236        return op;
237    }
238  }
239
240  static Value ReverseCompareOp(Value op) {
241    DCHECK(IsArithmeticCompareOp(op));
242    switch (op) {
243      case EQ: return EQ;
244      case NE: return NE;
245      case EQ_STRICT: return EQ_STRICT;
246      case NE_STRICT: return NE_STRICT;
247      case LT: return GT;
248      case GT: return LT;
249      case LTE: return GTE;
250      case GTE: return LTE;
251      default:
252        UNREACHABLE();
253        return op;
254    }
255  }
256
257  static bool IsBitOp(Value op) {
258    return (BIT_OR <= op && op <= SHR) || op == BIT_NOT;
259  }
260
261  static bool IsUnaryOp(Value op) {
262    return (NOT <= op && op <= VOID) || op == ADD || op == SUB;
263  }
264
265  static bool IsCountOp(Value op) {
266    return op == INC || op == DEC;
267  }
268
269  static bool IsShiftOp(Value op) {
270    return (SHL <= op) && (op <= SHR);
271  }
272
273  // Returns a string corresponding to the JS token string
274  // (.e., "<" for the token LT) or NULL if the token doesn't
275  // have a (unique) string (e.g. an IDENTIFIER).
276  static const char* String(Value tok) {
277    DCHECK(tok < NUM_TOKENS);  // tok is unsigned.
278    return string_[tok];
279  }
280
281  // Returns the precedence > 0 for binary and compare
282  // operators; returns 0 otherwise.
283  static int Precedence(Value tok) {
284    DCHECK(tok < NUM_TOKENS);  // tok is unsigned.
285    return precedence_[tok];
286  }
287
288 private:
289  static const char* const name_[NUM_TOKENS];
290  static const char* const string_[NUM_TOKENS];
291  static const int8_t precedence_[NUM_TOKENS];
292  static const char token_type[NUM_TOKENS];
293};
294
295} }  // namespace v8::internal
296
297#endif  // V8_TOKEN_H_
298