v8/src/token.h
2014-08-18 12:35:34 +00:00

295 lines
13 KiB
C++

// Copyright 2012 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef V8_TOKEN_H_
#define V8_TOKEN_H_
#include "src/base/logging.h"
namespace v8 {
namespace internal {
// TOKEN_LIST takes a list of 3 macros M, all of which satisfy the
// same signature M(name, string, precedence), where name is the
// symbolic token name, string is the corresponding syntactic symbol
// (or NULL, for literals), and precedence is the precedence (or 0).
// The parameters are invoked for token categories as follows:
//
// T: Non-keyword tokens
// K: Keyword tokens
// IGNORE_TOKEN is a convenience macro that can be supplied as
// an argument (at any position) for a TOKEN_LIST call. It does
// nothing with tokens belonging to the respective category.
#define IGNORE_TOKEN(name, string, precedence)
#define TOKEN_LIST(T, K) \
/* End of source indicator. */ \
T(EOS, "EOS", 0) \
\
/* Punctuators (ECMA-262, section 7.7, page 15). */ \
T(LPAREN, "(", 0) \
T(RPAREN, ")", 0) \
T(LBRACK, "[", 0) \
T(RBRACK, "]", 0) \
T(LBRACE, "{", 0) \
T(RBRACE, "}", 0) \
T(COLON, ":", 0) \
T(SEMICOLON, ";", 0) \
T(PERIOD, ".", 0) \
T(CONDITIONAL, "?", 3) \
T(INC, "++", 0) \
T(DEC, "--", 0) \
T(ARROW, "=>", 0) \
\
/* Assignment operators. */ \
/* IsAssignmentOp() and Assignment::is_compound() relies on */ \
/* this block of enum values being contiguous and sorted in the */ \
/* same order! */ \
T(INIT_VAR, "=init_var", 2) /* AST-use only. */ \
T(INIT_LET, "=init_let", 2) /* AST-use only. */ \
T(INIT_CONST, "=init_const", 2) /* AST-use only. */ \
T(INIT_CONST_LEGACY, "=init_const_legacy", 2) /* AST-use only. */ \
T(ASSIGN, "=", 2) \
T(ASSIGN_BIT_OR, "|=", 2) \
T(ASSIGN_BIT_XOR, "^=", 2) \
T(ASSIGN_BIT_AND, "&=", 2) \
T(ASSIGN_SHL, "<<=", 2) \
T(ASSIGN_SAR, ">>=", 2) \
T(ASSIGN_SHR, ">>>=", 2) \
T(ASSIGN_ADD, "+=", 2) \
T(ASSIGN_SUB, "-=", 2) \
T(ASSIGN_MUL, "*=", 2) \
T(ASSIGN_DIV, "/=", 2) \
T(ASSIGN_MOD, "%=", 2) \
\
/* Binary operators sorted by precedence. */ \
/* IsBinaryOp() relies on this block of enum values */ \
/* being contiguous and sorted in the same order! */ \
T(COMMA, ",", 1) \
T(OR, "||", 4) \
T(AND, "&&", 5) \
T(BIT_OR, "|", 6) \
T(BIT_XOR, "^", 7) \
T(BIT_AND, "&", 8) \
T(SHL, "<<", 11) \
T(SAR, ">>", 11) \
T(SHR, ">>>", 11) \
T(ROR, "rotate right", 11) /* only used by Crankshaft */ \
T(ADD, "+", 12) \
T(SUB, "-", 12) \
T(MUL, "*", 13) \
T(DIV, "/", 13) \
T(MOD, "%", 13) \
\
/* Compare operators sorted by precedence. */ \
/* IsCompareOp() relies on this block of enum values */ \
/* being contiguous and sorted in the same order! */ \
T(EQ, "==", 9) \
T(NE, "!=", 9) \
T(EQ_STRICT, "===", 9) \
T(NE_STRICT, "!==", 9) \
T(LT, "<", 10) \
T(GT, ">", 10) \
T(LTE, "<=", 10) \
T(GTE, ">=", 10) \
K(INSTANCEOF, "instanceof", 10) \
K(IN, "in", 10) \
\
/* Unary operators. */ \
/* IsUnaryOp() relies on this block of enum values */ \
/* being contiguous and sorted in the same order! */ \
T(NOT, "!", 0) \
T(BIT_NOT, "~", 0) \
K(DELETE, "delete", 0) \
K(TYPEOF, "typeof", 0) \
K(VOID, "void", 0) \
\
/* Keywords (ECMA-262, section 7.5.2, page 13). */ \
K(BREAK, "break", 0) \
K(CASE, "case", 0) \
K(CATCH, "catch", 0) \
K(CONTINUE, "continue", 0) \
K(DEBUGGER, "debugger", 0) \
K(DEFAULT, "default", 0) \
/* DELETE */ \
K(DO, "do", 0) \
K(ELSE, "else", 0) \
K(FINALLY, "finally", 0) \
K(FOR, "for", 0) \
K(FUNCTION, "function", 0) \
K(IF, "if", 0) \
/* IN */ \
/* INSTANCEOF */ \
K(NEW, "new", 0) \
K(RETURN, "return", 0) \
K(SWITCH, "switch", 0) \
K(THIS, "this", 0) \
K(THROW, "throw", 0) \
K(TRY, "try", 0) \
/* TYPEOF */ \
K(VAR, "var", 0) \
/* VOID */ \
K(WHILE, "while", 0) \
K(WITH, "with", 0) \
\
/* Literals (ECMA-262, section 7.8, page 16). */ \
K(NULL_LITERAL, "null", 0) \
K(TRUE_LITERAL, "true", 0) \
K(FALSE_LITERAL, "false", 0) \
T(NUMBER, NULL, 0) \
T(STRING, NULL, 0) \
\
/* Identifiers (not keywords or future reserved words). */ \
T(IDENTIFIER, NULL, 0) \
\
/* Future reserved words (ECMA-262, section 7.6.1.2). */ \
T(FUTURE_RESERVED_WORD, NULL, 0) \
T(FUTURE_STRICT_RESERVED_WORD, NULL, 0) \
K(CONST, "const", 0) \
K(EXPORT, "export", 0) \
K(IMPORT, "import", 0) \
K(LET, "let", 0) \
K(YIELD, "yield", 0) \
K(SUPER, "super", 0) \
\
/* Illegal token - not able to scan. */ \
T(ILLEGAL, "ILLEGAL", 0) \
\
/* Scanner-internal use only. */ \
T(WHITESPACE, NULL, 0)
class Token {
public:
// All token values.
#define T(name, string, precedence) name,
enum Value {
TOKEN_LIST(T, T)
NUM_TOKENS
};
#undef T
// Returns a string corresponding to the C++ token name
// (e.g. "LT" for the token LT).
static const char* Name(Value tok) {
DCHECK(tok < NUM_TOKENS); // tok is unsigned
return name_[tok];
}
// Predicates
static bool IsKeyword(Value tok) {
return token_type[tok] == 'K';
}
static bool IsAssignmentOp(Value tok) {
return INIT_VAR <= tok && tok <= ASSIGN_MOD;
}
static bool IsBinaryOp(Value op) {
return COMMA <= op && op <= MOD;
}
static bool IsTruncatingBinaryOp(Value op) {
return BIT_OR <= op && op <= ROR;
}
static bool IsCompareOp(Value op) {
return EQ <= op && op <= IN;
}
static bool IsOrderedRelationalCompareOp(Value op) {
return op == LT || op == LTE || op == GT || op == GTE;
}
static bool IsEqualityOp(Value op) {
return op == EQ || op == EQ_STRICT;
}
static bool IsInequalityOp(Value op) {
return op == NE || op == NE_STRICT;
}
static bool IsArithmeticCompareOp(Value op) {
return IsOrderedRelationalCompareOp(op) ||
IsEqualityOp(op) || IsInequalityOp(op);
}
static Value NegateCompareOp(Value op) {
DCHECK(IsArithmeticCompareOp(op));
switch (op) {
case EQ: return NE;
case NE: return EQ;
case EQ_STRICT: return NE_STRICT;
case NE_STRICT: return EQ_STRICT;
case LT: return GTE;
case GT: return LTE;
case LTE: return GT;
case GTE: return LT;
default:
UNREACHABLE();
return op;
}
}
static Value ReverseCompareOp(Value op) {
DCHECK(IsArithmeticCompareOp(op));
switch (op) {
case EQ: return EQ;
case NE: return NE;
case EQ_STRICT: return EQ_STRICT;
case NE_STRICT: return NE_STRICT;
case LT: return GT;
case GT: return LT;
case LTE: return GTE;
case GTE: return LTE;
default:
UNREACHABLE();
return op;
}
}
static bool IsBitOp(Value op) {
return (BIT_OR <= op && op <= SHR) || op == BIT_NOT;
}
static bool IsUnaryOp(Value op) {
return (NOT <= op && op <= VOID) || op == ADD || op == SUB;
}
static bool IsCountOp(Value op) {
return op == INC || op == DEC;
}
static bool IsShiftOp(Value op) {
return (SHL <= op) && (op <= SHR);
}
// Returns a string corresponding to the JS token string
// (.e., "<" for the token LT) or NULL if the token doesn't
// have a (unique) string (e.g. an IDENTIFIER).
static const char* String(Value tok) {
DCHECK(tok < NUM_TOKENS); // tok is unsigned.
return string_[tok];
}
// Returns the precedence > 0 for binary and compare
// operators; returns 0 otherwise.
static int Precedence(Value tok) {
DCHECK(tok < NUM_TOKENS); // tok is unsigned.
return precedence_[tok];
}
private:
static const char* const name_[NUM_TOKENS];
static const char* const string_[NUM_TOKENS];
static const int8_t precedence_[NUM_TOKENS];
static const char token_type[NUM_TOKENS];
};
} } // namespace v8::internal
#endif // V8_TOKEN_H_