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// 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_PARSING_TOKEN_H_
#define V8_PARSING_TOKEN_H_
#include "src/base/logging.h"
#include "src/globals.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 nullptr, 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
// C: Contextual keyword token
//
// Contextual keyword tokens are tokens that are scanned as Token::IDENTIFIER,
// but that in some contexts are treated as keywords. This mostly happens
// when ECMAScript introduces new keywords, but for backwards compatibility
// allows them to still be used as indentifiers in most contexts.
// 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, C) \
/* 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(ELLIPSIS, "...", 0) \
T(CONDITIONAL, "?", 3) \
T(INC, "++", 0) \
T(DEC, "--", 0) \
T(ARROW, "=>", 0) \
\
/* Assignment operators. */ \
/* IsAssignmentOp() relies on this block of enum values being */ \
/* contiguous and sorted in the same order! */ \
T(INIT, "=init", 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) \
T(ASSIGN_EXP, "**=", 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(ADD, "+", 12) \
T(SUB, "-", 12) \
T(MUL, "*", 13) \
T(DIV, "/", 13) \
T(MOD, "%", 13) \
T(EXP, "**", 14) \
\
/* 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, nullptr, 0) \
T(SMI, nullptr, 0) \
T(STRING, nullptr, 0) \
T(BIGINT, nullptr, 0) \
\
/* Identifiers (not keywords or future reserved words). */ \
T(IDENTIFIER, nullptr, 0) \
\
/* Future reserved words (ECMA-262, section 7.6.1.2). */ \
T(FUTURE_STRICT_RESERVED_WORD, nullptr, 0) \
K(ASYNC, "async", 0) \
/* `await` is a reserved word in module code only */ \
K(AWAIT, "await", 0) \
K(CLASS, "class", 0) \
K(CONST, "const", 0) \
K(ENUM, "enum", 0) \
K(EXPORT, "export", 0) \
K(EXTENDS, "extends", 0) \
K(IMPORT, "import", 0) \
K(LET, "let", 0) \
K(STATIC, "static", 0) \
K(YIELD, "yield", 0) \
K(SUPER, "super", 0) \
\
/* Illegal token - not able to scan. */ \
T(ILLEGAL, "ILLEGAL", 0) \
T(ESCAPED_KEYWORD, nullptr, 0) \
T(ESCAPED_STRICT_RESERVED_WORD, nullptr, 0) \
\
/* Scanner-internal use only. */ \
T(WHITESPACE, nullptr, 0) \
T(UNINITIALIZED, nullptr, 0) \
T(REGEXP_LITERAL, nullptr, 0) \
\
/* ES6 Template Literals */ \
T(TEMPLATE_SPAN, nullptr, 0) \
T(TEMPLATE_TAIL, nullptr, 0) \
\
/* Contextual keyword tokens */ \
C(GET, "get", 0) \
C(SET, "set", 0) \
C(OF, "of", 0) \
C(TARGET, "target", 0) \
C(SENT, "sent", 0) \
C(META, "meta", 0) \
C(AS, "as", 0) \
C(FROM, "from", 0) \
C(NAME, "name", 0) \
C(PROTO_UNDERSCORED, "__proto__", 0) \
C(CONSTRUCTOR, "constructor", 0) \
C(PROTOTYPE, "prototype", 0) \
C(EVAL, "eval", 0) \
C(ARGUMENTS, "arguments", 0) \
C(UNDEFINED, "undefined", 0) \
C(ANONYMOUS, "anonymous", 0)
class Token {
public:
// All token values.
#define T(name, string, precedence) name,
enum Value { TOKEN_LIST(T, 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 IsContextualKeyword(Value tok) { return token_type[tok] == 'C'; }
static bool IsIdentifier(Value tok, LanguageMode language_mode,
bool is_generator, bool disallow_await) {
switch (tok) {
case IDENTIFIER:
case ASYNC:
return true;
case ESCAPED_STRICT_RESERVED_WORD:
case FUTURE_STRICT_RESERVED_WORD:
case LET:
case STATIC:
return is_sloppy(language_mode);
case YIELD:
return !is_generator && is_sloppy(language_mode);
case AWAIT:
return !disallow_await;
default:
return false;
}
UNREACHABLE();
}
static bool IsAssignmentOp(Value tok) {
return INIT <= tok && tok <= ASSIGN_EXP;
}
static bool IsBinaryOp(Value op) { return COMMA <= op && op <= EXP; }
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 Value BinaryOpForAssignment(Value op) {
DCHECK(IsAssignmentOp(op));
switch (op) {
case Token::ASSIGN_BIT_OR:
return Token::BIT_OR;
case Token::ASSIGN_BIT_XOR:
return Token::BIT_XOR;
case Token::ASSIGN_BIT_AND:
return Token::BIT_AND;
case Token::ASSIGN_SHL:
return Token::SHL;
case Token::ASSIGN_SAR:
return Token::SAR;
case Token::ASSIGN_SHR:
return Token::SHR;
case Token::ASSIGN_ADD:
return Token::ADD;
case Token::ASSIGN_SUB:
return Token::SUB;
case Token::ASSIGN_MUL:
return Token::MUL;
case Token::ASSIGN_DIV:
return Token::DIV;
case Token::ASSIGN_MOD:
return Token::MOD;
case Token::ASSIGN_EXP:
return Token::EXP;
default:
UNREACHABLE();
}
}
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 nullptr 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];
}
static uint8_t StringLength(Value tok) {
DCHECK(tok < NUM_TOKENS);
return string_length_[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 uint8_t string_length_[NUM_TOKENS];
static const int8_t precedence_[NUM_TOKENS];
static const char token_type[NUM_TOKENS];
};
} // namespace internal
} // namespace v8
#endif // V8_PARSING_TOKEN_H_
|
