// Copyright 2011 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include <math.h>
#include "../include/v8stdint.h"
#include "allocation.h"
#include "checks.h"
#include "conversions.h"
#include "conversions-inl.h"
#include "globals.h"
#include "hashmap.h"
#include "list.h"
#include "preparse-data-format.h"
#include "preparse-data.h"
#include "preparser.h"
#include "unicode.h"
#include "utils.h"
namespace v8 {
#ifdef _MSC_VER
// Usually defined in math.h, but not in MSVC.
// Abstracted to work
int isfinite(double value);
#endif
namespace preparser {
PreParser::PreParseResult PreParser::PreParseLazyFunction(
i::LanguageMode mode, i::ParserRecorder* log) {
log_ = log;
// Lazy functions always have trivial outer scopes (no with/catch scopes).
Scope top_scope(&scope_, kTopLevelScope);
set_language_mode(mode);
Scope function_scope(&scope_, kFunctionScope);
ASSERT_EQ(i::Token::LBRACE, scanner_->current_token());
bool ok = true;
int start_position = scanner_->peek_location().beg_pos;
ParseLazyFunctionLiteralBody(&ok);
if (stack_overflow_) return kPreParseStackOverflow;
if (!ok) {
ReportUnexpectedToken(scanner_->current_token());
} else {
ASSERT_EQ(i::Token::RBRACE, scanner_->peek());
if (!is_classic_mode()) {
int end_pos = scanner_->location().end_pos;
CheckOctalLiteral(start_position, end_pos, &ok);
if (ok) {
CheckDelayedStrictModeViolation(start_position, end_pos, &ok);
}
}
}
return kPreParseSuccess;
}
// Preparsing checks a JavaScript program and emits preparse-data that helps
// a later parsing to be faster.
// See preparser-data.h for the data.
// The PreParser checks that the syntax follows the grammar for JavaScript,
// and collects some information about the program along the way.
// The grammar check is only performed in order to understand the program
// sufficiently to deduce some information about it, that can be used
// to speed up later parsing. Finding errors is not the goal of pre-parsing,
// rather it is to speed up properly written and correct programs.
// That means that contextual checks (like a label being declared where
// it is used) are generally omitted.
void PreParser::ReportUnexpectedToken(i::Token::Value token) {
// We don't report stack overflows here, to avoid increasing the
// stack depth even further. Instead we report it after parsing is
// over, in ParseProgram.
if (token == i::Token::ILLEGAL && stack_overflow_) {
return;
}
i::Scanner::Location source_location = scanner_->location();
// Four of the tokens are treated specially
switch (token) {
case i::Token::EOS:
return ReportMessageAt(source_location, "unexpected_eos", NULL);
case i::Token::NUMBER:
return ReportMessageAt(source_location, "unexpected_token_number", NULL);
case i::Token::STRING:
return ReportMessageAt(source_location, "unexpected_token_string", NULL);
case i::Token::IDENTIFIER:
return ReportMessageAt(source_location,
"unexpected_token_identifier", NULL);
case i::Token::FUTURE_RESERVED_WORD:
return ReportMessageAt(source_location, "unexpected_reserved", NULL);
case i::Token::FUTURE_STRICT_RESERVED_WORD:
return ReportMessageAt(source_location,
"unexpected_strict_reserved", NULL);
default:
const char* name = i::Token::String(token);
ReportMessageAt(source_location, "unexpected_token", name);
}
}
// Checks whether octal literal last seen is between beg_pos and end_pos.
// If so, reports an error.
void PreParser::CheckOctalLiteral(int beg_pos, int end_pos, bool* ok) {
i::Scanner::Location octal = scanner_->octal_position();
if (beg_pos <= octal.beg_pos && octal.end_pos <= end_pos) {
ReportMessageAt(octal, "strict_octal_literal", NULL);
scanner_->clear_octal_position();
*ok = false;
}
}
#define CHECK_OK ok); \
if (!*ok) return kUnknownSourceElements; \
((void)0
#define DUMMY ) // to make indentation work
#undef DUMMY
PreParser::Statement PreParser::ParseSourceElement(bool* ok) {
// (Ecma 262 5th Edition, clause 14):
// SourceElement:
// Statement
// FunctionDeclaration
//
// In harmony mode we allow additionally the following productions
// SourceElement:
// LetDeclaration
// ConstDeclaration
switch (peek()) {
case i::Token::FUNCTION:
return ParseFunctionDeclaration(ok);
case i::Token::LET:
case i::Token::CONST:
return ParseVariableStatement(kSourceElement, ok);
default:
return ParseStatement(ok);
}
}
PreParser::SourceElements PreParser::ParseSourceElements(int end_token,
bool* ok) {
// SourceElements ::
// (Statement)* <end_token>
bool allow_directive_prologue = true;
while (peek() != end_token) {
Statement statement = ParseSourceElement(CHECK_OK);
if (allow_directive_prologue) {
if (statement.IsUseStrictLiteral()) {
set_language_mode(harmony_scoping_ ?
i::EXTENDED_MODE : i::STRICT_MODE);
} else if (!statement.IsStringLiteral()) {
allow_directive_prologue = false;
}
}
}
return kUnknownSourceElements;
}
#undef CHECK_OK
#define CHECK_OK ok); \
if (!*ok) return Statement::Default(); \
((void)0
#define DUMMY ) // to make indentation work
#undef DUMMY
PreParser::Statement PreParser::ParseStatement(bool* ok) {
// Statement ::
// Block
// VariableStatement
// EmptyStatement
// ExpressionStatement
// IfStatement
// IterationStatement
// ContinueStatement
// BreakStatement
// ReturnStatement
// WithStatement
// LabelledStatement
// SwitchStatement
// ThrowStatement
// TryStatement
// DebuggerStatement
// Note: Since labels can only be used by 'break' and 'continue'
// statements, which themselves are only valid within blocks,
// iterations or 'switch' statements (i.e., BreakableStatements),
// labels can be simply ignored in all other cases; except for
// trivial labeled break statements 'label: break label' which is
// parsed into an empty statement.
// Keep the source position of the statement
switch (peek()) {
case i::Token::LBRACE:
return ParseBlock(ok);
case i::Token::CONST:
case i::Token::LET:
case i::Token::VAR:
return ParseVariableStatement(kStatement, ok);
case i::Token::SEMICOLON:
Next();
return Statement::Default();
case i::Token::IF:
return ParseIfStatement(ok);
case i::Token::DO:
return ParseDoWhileStatement(ok);
case i::Token::WHILE:
return ParseWhileStatement(ok);
case i::Token::FOR:
return ParseForStatement(ok);
case i::Token::CONTINUE:
return ParseContinueStatement(ok);
case i::Token::BREAK:
return ParseBreakStatement(ok);
case i::Token::RETURN:
return ParseReturnStatement(ok);
case i::Token::WITH:
return ParseWithStatement(ok);
case i::Token::SWITCH:
return ParseSwitchStatement(ok);
case i::Token::THROW:
return ParseThrowStatement(ok);
case i::Token::TRY:
return ParseTryStatement(ok);
case i::Token::FUNCTION: {
i::Scanner::Location start_location = scanner_->peek_location();
Statement statement = ParseFunctionDeclaration(CHECK_OK);
i::Scanner::Location end_location = scanner_->location();
if (!is_classic_mode()) {
ReportMessageAt(start_location.beg_pos, end_location.end_pos,
"strict_function", NULL);
*ok = false;
return Statement::Default();
} else {
return statement;
}
}
case i::Token::DEBUGGER:
return ParseDebuggerStatement(ok);
default:
return ParseExpressionOrLabelledStatement(ok);
}
}
PreParser::Statement PreParser::ParseFunctionDeclaration(bool* ok) {
// FunctionDeclaration ::
// 'function' Identifier '(' FormalParameterListopt ')' '{' FunctionBody '}'
Expect(i::Token::FUNCTION, CHECK_OK);
Identifier identifier = ParseIdentifier(CHECK_OK);
i::Scanner::Location location = scanner_->location();
Expression function_value = ParseFunctionLiteral(CHECK_OK);
if (function_value.IsStrictFunction() &&
!identifier.IsValidStrictVariable()) {
// Strict mode violation, using either reserved word or eval/arguments
// as name of strict function.
const char* type = "strict_function_name";
if (identifier.IsFutureStrictReserved()) {
type = "strict_reserved_word";
}
ReportMessageAt(location, type, NULL);
*ok = false;
}
return Statement::FunctionDeclaration();
}
PreParser::Statement PreParser::ParseBlock(bool* ok) {
// Block ::
// '{' Statement* '}'
// Note that a Block does not introduce a new execution scope!
// (ECMA-262, 3rd, 12.2)
//
Expect(i::Token::LBRACE, CHECK_OK);
while (peek() != i::Token::RBRACE) {
if (is_extended_mode()) {
ParseSourceElement(CHECK_OK);
} else {
ParseStatement(CHECK_OK);
}
}
Expect(i::Token::RBRACE, ok);
return Statement::Default();
}
PreParser::Statement PreParser::ParseVariableStatement(
VariableDeclarationContext var_context,
bool* ok) {
// VariableStatement ::
// VariableDeclarations ';'
Statement result = ParseVariableDeclarations(var_context,
NULL,
NULL,
CHECK_OK);
ExpectSemicolon(CHECK_OK);
return result;
}
// If the variable declaration declares exactly one non-const
// variable, then *var is set to that variable. In all other cases,
// *var is untouched; in particular, it is the caller's responsibility
// to initialize it properly. This mechanism is also used for the parsing
// of 'for-in' loops.
PreParser::Statement PreParser::ParseVariableDeclarations(
VariableDeclarationContext var_context,
VariableDeclarationProperties* decl_props,
int* num_decl,
bool* ok) {
// VariableDeclarations ::
// ('var' | 'const') (Identifier ('=' AssignmentExpression)?)+[',']
//
// The ES6 Draft Rev3 specifies the following grammar for const declarations
//
// ConstDeclaration ::
// const ConstBinding (',' ConstBinding)* ';'
// ConstBinding ::
// Identifier '=' AssignmentExpression
//
// TODO(ES6):
// ConstBinding ::
// BindingPattern '=' AssignmentExpression
bool require_initializer = false;
if (peek() == i::Token::VAR) {
Consume(i::Token::VAR);
} else if (peek() == i::Token::CONST) {
// TODO(ES6): The ES6 Draft Rev4 section 12.2.2 reads:
//
// ConstDeclaration : const ConstBinding (',' ConstBinding)* ';'
//
// * It is a Syntax Error if the code that matches this production is not
// contained in extended code.
//
// However disallowing const in classic mode will break compatibility with
// existing pages. Therefore we keep allowing const with the old
// non-harmony semantics in classic mode.
Consume(i::Token::CONST);
switch (language_mode()) {
case i::CLASSIC_MODE:
break;
case i::STRICT_MODE: {
i::Scanner::Location location = scanner_->peek_location();
ReportMessageAt(location, "strict_const", NULL);
*ok = false;
return Statement::Default();
}
case i::EXTENDED_MODE:
if (var_context != kSourceElement &&
var_context != kForStatement) {
i::Scanner::Location location = scanner_->peek_location();
ReportMessageAt(location.beg_pos, location.end_pos,
"unprotected_const", NULL);
*ok = false;
return Statement::Default();
}
require_initializer = true;
break;
}
} else if (peek() == i::Token::LET) {
// ES6 Draft Rev4 section 12.2.1:
//
// LetDeclaration : let LetBindingList ;
//
// * It is a Syntax Error if the code that matches this production is not
// contained in extended code.
if (!is_extended_mode()) {
i::Scanner::Location location = scanner_->peek_location();
ReportMessageAt(location.beg_pos, location.end_pos,
"illegal_let", NULL);
*ok = false;
return Statement::Default();
}
Consume(i::Token::LET);
if (var_context != kSourceElement &&
var_context != kForStatement) {
i::Scanner::Location location = scanner_->peek_location();
ReportMessageAt(location.beg_pos, location.end_pos,
"unprotected_let", NULL);
*ok = false;
return Statement::Default();
}
} else {
*ok = false;
return Statement::Default();
}
// The scope of a var/const declared variable anywhere inside a function
// is the entire function (ECMA-262, 3rd, 10.1.3, and 12.2). The scope
// of a let declared variable is the scope of the immediately enclosing
// block.
int nvars = 0; // the number of variables declared
do {
// Parse variable name.
if (nvars > 0) Consume(i::Token::COMMA);
Identifier identifier = ParseIdentifier(CHECK_OK);
if (!is_classic_mode() && !identifier.IsValidStrictVariable()) {
StrictModeIdentifierViolation(scanner_->location(),
"strict_var_name",
identifier,
ok);
return Statement::Default();
}
nvars++;
if (peek() == i::Token::ASSIGN || require_initializer) {
Expect(i::Token::ASSIGN, CHECK_OK);
ParseAssignmentExpression(var_context != kForStatement, CHECK_OK);
if (decl_props != NULL) *decl_props = kHasInitializers;
}
} while (peek() == i::Token::COMMA);
if (num_decl != NULL) *num_decl = nvars;
return Statement::Default();
}
PreParser::Statement PreParser::ParseExpressionOrLabelledStatement(bool* ok) {
// ExpressionStatement | LabelledStatement ::
// Expression ';'
// Identifier ':' Statement
Expression expr = ParseExpression(true, CHECK_OK);
if (expr.IsRawIdentifier()) {
ASSERT(!expr.AsIdentifier().IsFutureReserved());
ASSERT(is_classic_mode() || !expr.AsIdentifier().IsFutureStrictReserved());
if (peek() == i::Token::COLON) {
Consume(i::Token::COLON);
return ParseStatement(ok);
}
// Preparsing is disabled for extensions (because the extension details
// aren't passed to lazily compiled functions), so we don't
// accept "native function" in the preparser.
}
// Parsed expression statement.
ExpectSemicolon(CHECK_OK);
return Statement::ExpressionStatement(expr);
}
PreParser::Statement PreParser::ParseIfStatement(bool* ok) {
// IfStatement ::
// 'if' '(' Expression ')' Statement ('else' Statement)?
Expect(i::Token::IF, CHECK_OK);
Expect(i::Token::LPAREN, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(i::Token::RPAREN, CHECK_OK);
ParseStatement(CHECK_OK);
if (peek() == i::Token::ELSE) {
Next();
ParseStatement(CHECK_OK);
}
return Statement::Default();
}
PreParser::Statement PreParser::ParseContinueStatement(bool* ok) {
// ContinueStatement ::
// 'continue' [no line terminator] Identifier? ';'
Expect(i::Token::CONTINUE, CHECK_OK);
i::Token::Value tok = peek();
if (!scanner_->HasAnyLineTerminatorBeforeNext() &&
tok != i::Token::SEMICOLON &&
tok != i::Token::RBRACE &&
tok != i::Token::EOS) {
ParseIdentifier(CHECK_OK);
}
ExpectSemicolon(CHECK_OK);
return Statement::Default();
}
PreParser::Statement PreParser::ParseBreakStatement(bool* ok) {
// BreakStatement ::
// 'break' [no line terminator] Identifier? ';'
Expect(i::Token::BREAK, CHECK_OK);
i::Token::Value tok = peek();
if (!scanner_->HasAnyLineTerminatorBeforeNext() &&
tok != i::Token::SEMICOLON &&
tok != i::Token::RBRACE &&
tok != i::Token::EOS) {
ParseIdentifier(CHECK_OK);
}
ExpectSemicolon(CHECK_OK);
return Statement::Default();
}
PreParser::Statement PreParser::ParseReturnStatement(bool* ok) {
// ReturnStatement ::
// 'return' [no line terminator] Expression? ';'
// Consume the return token. It is necessary to do the before
// reporting any errors on it, because of the way errors are
// reported (underlining).
Expect(i::Token::RETURN, CHECK_OK);
// An ECMAScript program is considered syntactically incorrect if it
// contains a return statement that is not within the body of a
// function. See ECMA-262, section 12.9, page 67.
// This is not handled during preparsing.
i::Token::Value tok = peek();
if (!scanner_->HasAnyLineTerminatorBeforeNext() &&
tok != i::Token::SEMICOLON &&
tok != i::Token::RBRACE &&
tok != i::Token::EOS) {
ParseExpression(true, CHECK_OK);
}
ExpectSemicolon(CHECK_OK);
return Statement::Default();
}
PreParser::Statement PreParser::ParseWithStatement(bool* ok) {
// WithStatement ::
// 'with' '(' Expression ')' Statement
Expect(i::Token::WITH, CHECK_OK);
if (!is_classic_mode()) {
i::Scanner::Location location = scanner_->location();
ReportMessageAt(location, "strict_mode_with", NULL);
*ok = false;
return Statement::Default();
}
Expect(i::Token::LPAREN, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(i::Token::RPAREN, CHECK_OK);
scope_->EnterWith();
ParseStatement(CHECK_OK);
scope_->LeaveWith();
return Statement::Default();
}
PreParser::Statement PreParser::ParseSwitchStatement(bool* ok) {
// SwitchStatement ::
// 'switch' '(' Expression ')' '{' CaseClause* '}'
Expect(i::Token::SWITCH, CHECK_OK);
Expect(i::Token::LPAREN, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(i::Token::RPAREN, CHECK_OK);
Expect(i::Token::LBRACE, CHECK_OK);
i::Token::Value token = peek();
while (token != i::Token::RBRACE) {
if (token == i::Token::CASE) {
Expect(i::Token::CASE, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(i::Token::COLON, CHECK_OK);
} else if (token == i::Token::DEFAULT) {
Expect(i::Token::DEFAULT, CHECK_OK);
Expect(i::Token::COLON, CHECK_OK);
} else {
ParseStatement(CHECK_OK);
}
token = peek();
}
Expect(i::Token::RBRACE, ok);
return Statement::Default();
}
PreParser::Statement PreParser::ParseDoWhileStatement(bool* ok) {
// DoStatement ::
// 'do' Statement 'while' '(' Expression ')' ';'
Expect(i::Token::DO, CHECK_OK);
ParseStatement(CHECK_OK);
Expect(i::Token::WHILE, CHECK_OK);
Expect(i::Token::LPAREN, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(i::Token::RPAREN, ok);
if (peek() == i::Token::SEMICOLON) Consume(i::Token::SEMICOLON);
return Statement::Default();
}
PreParser::Statement PreParser::ParseWhileStatement(bool* ok) {
// WhileStatement ::
// 'while' '(' Expression ')' Statement
Expect(i::Token::WHILE, CHECK_OK);
Expect(i::Token::LPAREN, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(i::Token::RPAREN, CHECK_OK);
ParseStatement(ok);
return Statement::Default();
}
PreParser::Statement PreParser::ParseForStatement(bool* ok) {
// ForStatement ::
// 'for' '(' Expression? ';' Expression? ';' Expression? ')' Statement
Expect(i::Token::FOR, CHECK_OK);
Expect(i::Token::LPAREN, CHECK_OK);
if (peek() != i::Token::SEMICOLON) {
if (peek() == i::Token::VAR || peek() == i::Token::CONST ||
peek() == i::Token::LET) {
bool is_let = peek() == i::Token::LET;
int decl_count;
VariableDeclarationProperties decl_props = kHasNoInitializers;
ParseVariableDeclarations(
kForStatement, &decl_props, &decl_count, CHECK_OK);
bool accept_IN = decl_count == 1 &&
!(is_let && decl_props == kHasInitializers);
if (peek() == i::Token::IN && accept_IN) {
Expect(i::Token::IN, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(i::Token::RPAREN, CHECK_OK);
ParseStatement(CHECK_OK);
return Statement::Default();
}
} else {
ParseExpression(false, CHECK_OK);
if (peek() == i::Token::IN) {
Expect(i::Token::IN, CHECK_OK);
ParseExpression(true, CHECK_OK);
Expect(i::Token::RPAREN, CHECK_OK);
ParseStatement(CHECK_OK);
return Statement::Default();
}
}
}
// Parsed initializer at this point.
Expect(i::Token::SEMICOLON, CHECK_OK);
if (peek() != i::Token::SEMICOLON) {
ParseExpression(true, CHECK_OK);
}
Expect(i::Token::SEMICOLON, CHECK_OK);
if (peek() != i::Token::RPAREN) {
ParseExpression(true, CHECK_OK);
}
Expect(i::Token::RPAREN, CHECK_OK);
ParseStatement(ok);
return Statement::Default();
}
PreParser::Statement PreParser::ParseThrowStatement(bool* ok) {
// ThrowStatement ::
// 'throw' [no line terminator] Expression ';'
Expect(i::Token::THROW, CHECK_OK);
if (scanner_->HasAnyLineTerminatorBeforeNext()) {
i::Scanner::Location pos = scanner_->location();
ReportMessageAt(pos, "newline_after_throw", NULL);
*ok = false;
return Statement::Default();
}
ParseExpression(true, CHECK_OK);
ExpectSemicolon(ok);
return Statement::Default();
}
PreParser::Statement PreParser::ParseTryStatement(bool* ok) {
// TryStatement ::
// 'try' Block Catch
// 'try' Block Finally
// 'try' Block Catch Finally
//
// Catch ::
// 'catch' '(' Identifier ')' Block
//
// Finally ::
// 'finally' Block
// In preparsing, allow any number of catch/finally blocks, including zero
// of both.
Expect(i::Token::TRY, CHECK_OK);
ParseBlock(CHECK_OK);
bool catch_or_finally_seen = false;
if (peek() == i::Token::CATCH) {
Consume(i::Token::CATCH);
Expect(i::Token::LPAREN, CHECK_OK);
Identifier id = ParseIdentifier(CHECK_OK);
if (!is_classic_mode() && !id.IsValidStrictVariable()) {
StrictModeIdentifierViolation(scanner_->location(),
"strict_catch_variable",
id,
ok);
return Statement::Default();
}
Expect(i::Token::RPAREN, CHECK_OK);
scope_->EnterWith();
ParseBlock(ok);
scope_->LeaveWith();
if (!*ok) Statement::Default();
catch_or_finally_seen = true;
}
if (peek() == i::Token::FINALLY) {
Consume(i::Token::FINALLY);
ParseBlock(CHECK_OK);
catch_or_finally_seen = true;
}
if (!catch_or_finally_seen) {
*ok = false;
}
return Statement::Default();
}
PreParser::Statement PreParser::ParseDebuggerStatement(bool* ok) {
// In ECMA-262 'debugger' is defined as a reserved keyword. In some browser
// contexts this is used as a statement which invokes the debugger as if a
// break point is present.
// DebuggerStatement ::
// 'debugger' ';'
Expect(i::Token::DEBUGGER, CHECK_OK);
ExpectSemicolon(ok);
return Statement::Default();
}
#undef CHECK_OK
#define CHECK_OK ok); \
if (!*ok) return Expression::Default(); \
((void)0
#define DUMMY ) // to make indentation work
#undef DUMMY
// Precedence = 1
PreParser::Expression PreParser::ParseExpression(bool accept_IN, bool* ok) {
// Expression ::
// AssignmentExpression
// Expression ',' AssignmentExpression
Expression result = ParseAssignmentExpression(accept_IN, CHECK_OK);
while (peek() == i::Token::COMMA) {
Expect(i::Token::COMMA, CHECK_OK);
ParseAssignmentExpression(accept_IN, CHECK_OK);
result = Expression::Default();
}
return result;
}
// Precedence = 2
PreParser::Expression PreParser::ParseAssignmentExpression(bool accept_IN,
bool* ok) {
// AssignmentExpression ::
// ConditionalExpression
// LeftHandSideExpression AssignmentOperator AssignmentExpression
i::Scanner::Location before = scanner_->peek_location();
Expression expression = ParseConditionalExpression(accept_IN, CHECK_OK);
if (!i::Token::IsAssignmentOp(peek())) {
// Parsed conditional expression only (no assignment).
return expression;
}
if (!is_classic_mode() &&
expression.IsIdentifier() &&
expression.AsIdentifier().IsEvalOrArguments()) {
i::Scanner::Location after = scanner_->location();
ReportMessageAt(before.beg_pos, after.end_pos,
"strict_lhs_assignment", NULL);
*ok = false;
return Expression::Default();
}
i::Token::Value op = Next(); // Get assignment operator.
ParseAssignmentExpression(accept_IN, CHECK_OK);
if ((op == i::Token::ASSIGN) && expression.IsThisProperty()) {
scope_->AddProperty();
}
return Expression::Default();
}
// Precedence = 3
PreParser::Expression PreParser::ParseConditionalExpression(bool accept_IN,
bool* ok) {
// ConditionalExpression ::
// LogicalOrExpression
// LogicalOrExpression '?' AssignmentExpression ':' AssignmentExpression
// We start using the binary expression parser for prec >= 4 only!
Expression expression = ParseBinaryExpression(4, accept_IN, CHECK_OK);
if (peek() != i::Token::CONDITIONAL) return expression;
Consume(i::Token::CONDITIONAL);
// In parsing the first assignment expression in conditional
// expressions we always accept the 'in' keyword; see ECMA-262,
// section 11.12, page 58.
ParseAssignmentExpression(true, CHECK_OK);
Expect(i::Token::COLON, CHECK_OK);
ParseAssignmentExpression(accept_IN, CHECK_OK);
return Expression::Default();
}
int PreParser::Precedence(i::Token::Value tok, bool accept_IN) {
if (tok == i::Token::IN && !accept_IN)
return 0; // 0 precedence will terminate binary expression parsing
return i::Token::Precedence(tok);
}
// Precedence >= 4
PreParser::Expression PreParser::ParseBinaryExpression(int prec,
bool accept_IN,
bool* ok) {
Expression result = ParseUnaryExpression(CHECK_OK);
for (int prec1 = Precedence(peek(), accept_IN); prec1 >= prec; prec1--) {
// prec1 >= 4
while (Precedence(peek(), accept_IN) == prec1) {
Next();
ParseBinaryExpression(prec1 + 1, accept_IN, CHECK_OK);
result = Expression::Default();
}
}
return result;
}
PreParser::Expression PreParser::ParseUnaryExpression(bool* ok) {
// UnaryExpression ::
// PostfixExpression
// 'delete' UnaryExpression
// 'void' UnaryExpression
// 'typeof' UnaryExpression
// '++' UnaryExpression
// '--' UnaryExpression
// '+' UnaryExpression
// '-' UnaryExpression
// '~' UnaryExpression
// '!' UnaryExpression
i::Token::Value op = peek();
if (i::Token::IsUnaryOp(op)) {
op = Next();
ParseUnaryExpression(ok);
return Expression::Default();
} else if (i::Token::IsCountOp(op)) {
op = Next();
i::Scanner::Location before = scanner_->peek_location();
Expression expression = ParseUnaryExpression(CHECK_OK);
if (!is_classic_mode() &&
expression.IsIdentifier() &&
expression.AsIdentifier().IsEvalOrArguments()) {
i::Scanner::Location after = scanner_->location();
ReportMessageAt(before.beg_pos, after.end_pos,
"strict_lhs_prefix", NULL);
*ok = false;
}
return Expression::Default();
} else {
return ParsePostfixExpression(ok);
}
}
PreParser::Expression PreParser::ParsePostfixExpression(bool* ok) {
// PostfixExpression ::
// LeftHandSideExpression ('++' | '--')?
i::Scanner::Location before = scanner_->peek_location();
Expression expression = ParseLeftHandSideExpression(CHECK_OK);
if (!scanner_->HasAnyLineTerminatorBeforeNext() &&
i::Token::IsCountOp(peek())) {
if (!is_classic_mode() &&
expression.IsIdentifier() &&
expression.AsIdentifier().IsEvalOrArguments()) {
i::Scanner::Location after = scanner_->location();
ReportMessageAt(before.beg_pos, after.end_pos,
"strict_lhs_postfix", NULL);
*ok = false;
return Expression::Default();
}
Next();
return Expression::Default();
}
return expression;
}
PreParser::Expression PreParser::ParseLeftHandSideExpression(bool* ok) {
// LeftHandSideExpression ::
// (NewExpression | MemberExpression) ...
Expression result = Expression::Default();
if (peek() == i::Token::NEW) {
result = ParseNewExpression(CHECK_OK);
} else {
result = ParseMemberExpression(CHECK_OK);
}
while (true) {
switch (peek()) {
case i::Token::LBRACK: {
Consume(i::Token::LBRACK);
ParseExpression(true, CHECK_OK);
Expect(i::Token::RBRACK, CHECK_OK);
if (result.IsThis()) {
result = Expression::ThisProperty();
} else {
result = Expression::Default();
}
break;
}
case i::Token::LPAREN: {
ParseArguments(CHECK_OK);
result = Expression::Default();
break;
}
case i::Token::PERIOD: {
Consume(i::Token::PERIOD);
ParseIdentifierName(CHECK_OK);
if (result.IsThis()) {
result = Expression::ThisProperty();
} else {
result = Expression::Default();
}
break;
}
default:
return result;
}
}
}
PreParser::Expression PreParser::ParseNewExpression(bool* ok) {
// NewExpression ::
// ('new')+ MemberExpression
// The grammar for new expressions is pretty warped. The keyword
// 'new' can either be a part of the new expression (where it isn't
// followed by an argument list) or a part of the member expression,
// where it must be followed by an argument list. To accommodate
// this, we parse the 'new' keywords greedily and keep track of how
// many we have parsed. This information is then passed on to the
// member expression parser, which is only allowed to match argument
// lists as long as it has 'new' prefixes left
unsigned new_count = 0;
do {
Consume(i::Token::NEW);
new_count++;
} while (peek() == i::Token::NEW);
return ParseMemberWithNewPrefixesExpression(new_count, ok);
}
PreParser::Expression PreParser::ParseMemberExpression(bool* ok) {
return ParseMemberWithNewPrefixesExpression(0, ok);
}
PreParser::Expression PreParser::ParseMemberWithNewPrefixesExpression(
unsigned new_count, bool* ok) {
// MemberExpression ::
// (PrimaryExpression | FunctionLiteral)
// ('[' Expression ']' | '.' Identifier | Arguments)*
// Parse the initial primary or function expression.
Expression result = Expression::Default();
if (peek() == i::Token::FUNCTION) {
Consume(i::Token::FUNCTION);
Identifier identifier = Identifier::Default();
if (peek_any_identifier()) {
identifier = ParseIdentifier(CHECK_OK);
}
result = ParseFunctionLiteral(CHECK_OK);
if (result.IsStrictFunction() && !identifier.IsValidStrictVariable()) {
StrictModeIdentifierViolation(scanner_->location(),
"strict_function_name",
identifier,
ok);
return Expression::Default();
}
} else {
result = ParsePrimaryExpression(CHECK_OK);
}
while (true) {
switch (peek()) {
case i::Token::LBRACK: {
Consume(i::Token::LBRACK);
ParseExpression(true, CHECK_OK);
Expect(i::Token::RBRACK, CHECK_OK);
if (result.IsThis()) {
result = Expression::ThisProperty();
} else {
result = Expression::Default();
}
break;
}
case i::Token::PERIOD: {
Consume(i::Token::PERIOD);
ParseIdentifierName(CHECK_OK);
if (result.IsThis()) {
result = Expression::ThisProperty();
} else {
result = Expression::Default();
}
break;
}
case i::Token::LPAREN: {
if (new_count == 0) return result;
// Consume one of the new prefixes (already parsed).
ParseArguments(CHECK_OK);
new_count--;
result = Expression::Default();
break;
}
default:
return result;
}
}
}
PreParser::Expression PreParser::ParsePrimaryExpression(bool* ok) {
// PrimaryExpression ::
// 'this'
// 'null'
// 'true'
// 'false'
// Identifier
// Number
// String
// ArrayLiteral
// ObjectLiteral
// RegExpLiteral
// '(' Expression ')'
Expression result = Expression::Default();
switch (peek()) {
case i::Token::THIS: {
Next();
result = Expression::This();
break;
}
case i::Token::FUTURE_RESERVED_WORD: {
Next();
i::Scanner::Location location = scanner_->location();
ReportMessageAt(location.beg_pos, location.end_pos,
"reserved_word", NULL);
*ok = false;
return Expression::Default();
}
case i::Token::FUTURE_STRICT_RESERVED_WORD:
if (!is_classic_mode()) {
Next();
i::Scanner::Location location = scanner_->location();
ReportMessageAt(location, "strict_reserved_word", NULL);
*ok = false;
return Expression::Default();
}
// FALLTHROUGH
case i::Token::IDENTIFIER: {
Identifier id = ParseIdentifier(CHECK_OK);
result = Expression::FromIdentifier(id);
break;
}
case i::Token::NULL_LITERAL:
case i::Token::TRUE_LITERAL:
case i::Token::FALSE_LITERAL:
case i::Token::NUMBER: {
Next();
break;
}
case i::Token::STRING: {
Next();
result = GetStringSymbol();
break;
}
case i::Token::ASSIGN_DIV:
result = ParseRegExpLiteral(true, CHECK_OK);
break;
case i::Token::DIV:
result = ParseRegExpLiteral(false, CHECK_OK);
break;
case i::Token::LBRACK:
result = ParseArrayLiteral(CHECK_OK);
break;
case i::Token::LBRACE:
result = ParseObjectLiteral(CHECK_OK);
break;
case i::Token::LPAREN:
Consume(i::Token::LPAREN);
parenthesized_function_ = (peek() == i::Token::FUNCTION);
result = ParseExpression(true, CHECK_OK);
Expect(i::Token::RPAREN, CHECK_OK);
result = result.Parenthesize();
break;
case i::Token::MOD:
result = ParseV8Intrinsic(CHECK_OK);
break;
default: {
Next();
*ok = false;
return Expression::Default();
}
}
return result;
}
PreParser::Expression PreParser::ParseArrayLiteral(bool* ok) {
// ArrayLiteral ::
// '[' Expression? (',' Expression?)* ']'
Expect(i::Token::LBRACK, CHECK_OK);
while (peek() != i::Token::RBRACK) {
if (peek() != i::Token::COMMA) {
ParseAssignmentExpression(true, CHECK_OK);
}
if (peek() != i::Token::RBRACK) {
Expect(i::Token::COMMA, CHECK_OK);
}
}
Expect(i::Token::RBRACK, CHECK_OK);
scope_->NextMaterializedLiteralIndex();
return Expression::Default();
}
void PreParser::CheckDuplicate(DuplicateFinder* finder,
i::Token::Value property,
int type,
bool* ok) {
int old_type;
if (property == i::Token::NUMBER) {
old_type = finder->AddNumber(scanner_->literal_ascii_string(), type);
} else if (scanner_->is_literal_ascii()) {
old_type = finder->AddAsciiSymbol(scanner_->literal_ascii_string(),
type);
} else {
old_type = finder->AddUtf16Symbol(scanner_->literal_utf16_string(), type);
}
if (HasConflict(old_type, type)) {
if (IsDataDataConflict(old_type, type)) {
// Both are data properties.
if (is_classic_mode()) return;
ReportMessageAt(scanner_->location(),
"strict_duplicate_property", NULL);
} else if (IsDataAccessorConflict(old_type, type)) {
// Both a data and an accessor property with the same name.
ReportMessageAt(scanner_->location(),
"accessor_data_property", NULL);
} else {
ASSERT(IsAccessorAccessorConflict(old_type, type));
// Both accessors of the same type.
ReportMessageAt(scanner_->location(),
"accessor_get_set", NULL);
}
*ok = false;
}
}
PreParser::Expression PreParser::ParseObjectLiteral(bool* ok) {
// ObjectLiteral ::
// '{' (
// ((IdentifierName | String | Number) ':' AssignmentExpression)
// | (('get' | 'set') (IdentifierName | String | Number) FunctionLiteral)
// )*[','] '}'
Expect(i::Token::LBRACE, CHECK_OK);
DuplicateFinder duplicate_finder(scanner_->unicode_cache());
while (peek() != i::Token::RBRACE) {
i::Token::Value next = peek();
switch (next) {
case i::Token::IDENTIFIER:
case i::Token::FUTURE_RESERVED_WORD:
case i::Token::FUTURE_STRICT_RESERVED_WORD: {
bool is_getter = false;
bool is_setter = false;
ParseIdentifierNameOrGetOrSet(&is_getter, &is_setter, CHECK_OK);
if ((is_getter || is_setter) && peek() != i::Token::COLON) {
i::Token::Value name = Next();
bool is_keyword = i::Token::IsKeyword(name);
if (name != i::Token::IDENTIFIER &&
name != i::Token::FUTURE_RESERVED_WORD &&
name != i::Token::FUTURE_STRICT_RESERVED_WORD &&
name != i::Token::NUMBER &&
name != i::Token::STRING &&
!is_keyword) {
*ok = false;
return Expression::Default();
}
if (!is_keyword) {
LogSymbol();
}
PropertyType type = is_getter ? kGetterProperty : kSetterProperty;
CheckDuplicate(&duplicate_finder, name, type, CHECK_OK);
ParseFunctionLiteral(CHECK_OK);
if (peek() != i::Token::RBRACE) {
Expect(i::Token::COMMA, CHECK_OK);
}
continue; // restart the while
}
CheckDuplicate(&duplicate_finder, next, kValueProperty, CHECK_OK);
break;
}
case i::Token::STRING:
Consume(next);
CheckDuplicate(&duplicate_finder, next, kValueProperty, CHECK_OK);
GetStringSymbol();
break;
case i::Token::NUMBER:
Consume(next);
CheckDuplicate(&duplicate_finder, next, kValueProperty, CHECK_OK);
break;
default:
if (i::Token::IsKeyword(next)) {
Consume(next);
CheckDuplicate(&duplicate_finder, next, kValueProperty, CHECK_OK);
} else {
// Unexpected token.
*ok = false;
return Expression::Default();
}
}
Expect(i::Token::COLON, CHECK_OK);
ParseAssignmentExpression(true, CHECK_OK);
// TODO(1240767): Consider allowing trailing comma.
if (peek() != i::Token::RBRACE) Expect(i::Token::COMMA, CHECK_OK);
}
Expect(i::Token::RBRACE, CHECK_OK);
scope_->NextMaterializedLiteralIndex();
return Expression::Default();
}
PreParser::Expression PreParser::ParseRegExpLiteral(bool seen_equal,
bool* ok) {
if (!scanner_->ScanRegExpPattern(seen_equal)) {
Next();
ReportMessageAt(scanner_->location(), "unterminated_regexp", NULL);
*ok = false;
return Expression::Default();
}
scope_->NextMaterializedLiteralIndex();
if (!scanner_->ScanRegExpFlags()) {
Next();
ReportMessageAt(scanner_->location(), "invalid_regexp_flags", NULL);
*ok = false;
return Expression::Default();
}
Next();
return Expression::Default();
}
PreParser::Arguments PreParser::ParseArguments(bool* ok) {
// Arguments ::
// '(' (AssignmentExpression)*[','] ')'
Expect(i::Token::LPAREN, ok);
if (!*ok) return -1;
bool done = (peek() == i::Token::RPAREN);
int argc = 0;
while (!done) {
ParseAssignmentExpression(true, ok);
if (!*ok) return -1;
argc++;
done = (peek() == i::Token::RPAREN);
if (!done) {
Expect(i::Token::COMMA, ok);
if (!*ok) return -1;
}
}
Expect(i::Token::RPAREN, ok);
return argc;
}
PreParser::Expression PreParser::ParseFunctionLiteral(bool* ok) {
// Function ::
// '(' FormalParameterList? ')' '{' FunctionBody '}'
// Parse function body.
ScopeType outer_scope_type = scope_->type();
bool inside_with = scope_->IsInsideWith();
Scope function_scope(&scope_, kFunctionScope);
// FormalParameterList ::
// '(' (Identifier)*[','] ')'
Expect(i::Token::LPAREN, CHECK_OK);
int start_position = scanner_->location().beg_pos;
bool done = (peek() == i::Token::RPAREN);
DuplicateFinder duplicate_finder(scanner_->unicode_cache());
while (!done) {
Identifier id = ParseIdentifier(CHECK_OK);
if (!id.IsValidStrictVariable()) {
StrictModeIdentifierViolation(scanner_->location(),
"strict_param_name",
id,
CHECK_OK);
}
int prev_value;
if (scanner_->is_literal_ascii()) {
prev_value =
duplicate_finder.AddAsciiSymbol(scanner_->literal_ascii_string(), 1);
} else {
prev_value =
duplicate_finder.AddUtf16Symbol(scanner_->literal_utf16_string(), 1);
}
if (prev_value != 0) {
SetStrictModeViolation(scanner_->location(),
"strict_param_dupe",
CHECK_OK);
}
done = (peek() == i::Token::RPAREN);
if (!done) {
Expect(i::Token::COMMA, CHECK_OK);
}
}
Expect(i::Token::RPAREN, CHECK_OK);
// Determine if the function will be lazily compiled.
// Currently only happens to top-level functions.
// Optimistically assume that all top-level functions are lazily compiled.
bool is_lazily_compiled = (outer_scope_type == kTopLevelScope &&
!inside_with && allow_lazy_ &&
!parenthesized_function_);
parenthesized_function_ = false;
Expect(i::Token::LBRACE, CHECK_OK);
if (is_lazily_compiled) {
ParseLazyFunctionLiteralBody(CHECK_OK);
} else {
ParseSourceElements(i::Token::RBRACE, ok);
}
Expect(i::Token::RBRACE, CHECK_OK);
if (!is_classic_mode()) {
int end_position = scanner_->location().end_pos;
CheckOctalLiteral(start_position, end_position, CHECK_OK);
CheckDelayedStrictModeViolation(start_position, end_position, CHECK_OK);
return Expression::StrictFunction();
}
return Expression::Default();
}
void PreParser::ParseLazyFunctionLiteralBody(bool* ok) {
int body_start = scanner_->location().beg_pos;
log_->PauseRecording();
ParseSourceElements(i::Token::RBRACE, ok);
log_->ResumeRecording();
if (!*ok) return;
// Position right after terminal '}'.
ASSERT_EQ(i::Token::RBRACE, scanner_->peek());
int body_end = scanner_->peek_location().end_pos;
log_->LogFunction(body_start, body_end,
scope_->materialized_literal_count(),
scope_->expected_properties(),
language_mode());
}
PreParser::Expression PreParser::ParseV8Intrinsic(bool* ok) {
// CallRuntime ::
// '%' Identifier Arguments
Expect(i::Token::MOD, CHECK_OK);
if (!allow_natives_syntax_) {
*ok = false;
return Expression::Default();
}
ParseIdentifier(CHECK_OK);
ParseArguments(ok);
return Expression::Default();
}
#undef CHECK_OK
void PreParser::ExpectSemicolon(bool* ok) {
// Check for automatic semicolon insertion according to
// the rules given in ECMA-262, section 7.9, page 21.
i::Token::Value tok = peek();
if (tok == i::Token::SEMICOLON) {
Next();
return;
}
if (scanner_->HasAnyLineTerminatorBeforeNext() ||
tok == i::Token::RBRACE ||
tok == i::Token::EOS) {
return;
}
Expect(i::Token::SEMICOLON, ok);
}
void PreParser::LogSymbol() {
int identifier_pos = scanner_->location().beg_pos;
if (scanner_->is_literal_ascii()) {
log_->LogAsciiSymbol(identifier_pos, scanner_->literal_ascii_string());
} else {
log_->LogUtf16Symbol(identifier_pos, scanner_->literal_utf16_string());
}
}
PreParser::Expression PreParser::GetStringSymbol() {
const int kUseStrictLength = 10;
const char* kUseStrictChars = "use strict";
LogSymbol();
if (scanner_->is_literal_ascii() &&
scanner_->literal_length() == kUseStrictLength &&
!scanner_->literal_contains_escapes() &&
!strncmp(scanner_->literal_ascii_string().start(), kUseStrictChars,
kUseStrictLength)) {
return Expression::UseStrictStringLiteral();
}
return Expression::StringLiteral();
}
PreParser::Identifier PreParser::GetIdentifierSymbol() {
LogSymbol();
if (scanner_->current_token() == i::Token::FUTURE_RESERVED_WORD) {
return Identifier::FutureReserved();
} else if (scanner_->current_token() ==
i::Token::FUTURE_STRICT_RESERVED_WORD) {
return Identifier::FutureStrictReserved();
}
if (scanner_->is_literal_ascii()) {
// Detect strict-mode poison words.
if (scanner_->literal_length() == 4 &&
!strncmp(scanner_->literal_ascii_string().start(), "eval", 4)) {
return Identifier::Eval();
}
if (scanner_->literal_length() == 9 &&
!strncmp(scanner_->literal_ascii_string().start(), "arguments", 9)) {
return Identifier::Arguments();
}
}
return Identifier::Default();
}
PreParser::Identifier PreParser::ParseIdentifier(bool* ok) {
i::Token::Value next = Next();
switch (next) {
case i::Token::FUTURE_RESERVED_WORD: {
i::Scanner::Location location = scanner_->location();
ReportMessageAt(location.beg_pos, location.end_pos,
"reserved_word", NULL);
*ok = false;
return GetIdentifierSymbol();
}
case i::Token::FUTURE_STRICT_RESERVED_WORD:
if (!is_classic_mode()) {
i::Scanner::Location location = scanner_->location();
ReportMessageAt(location.beg_pos, location.end_pos,
"strict_reserved_word", NULL);
*ok = false;
}
// FALLTHROUGH
case i::Token::IDENTIFIER:
return GetIdentifierSymbol();
default:
*ok = false;
return Identifier::Default();
}
}
void PreParser::SetStrictModeViolation(i::Scanner::Location location,
const char* type,
bool* ok) {
if (!is_classic_mode()) {
ReportMessageAt(location, type, NULL);
*ok = false;
return;
}
// Delay report in case this later turns out to be strict code
// (i.e., for function names and parameters prior to a "use strict"
// directive).
// It's safe to overwrite an existing violation.
// It's either from a function that turned out to be non-strict,
// or it's in the current function (and we just need to report
// one error), or it's in a unclosed nesting function that wasn't
// strict (otherwise we would already be in strict mode).
strict_mode_violation_location_ = location;
strict_mode_violation_type_ = type;
}
void PreParser::CheckDelayedStrictModeViolation(int beg_pos,
int end_pos,
bool* ok) {
i::Scanner::Location location = strict_mode_violation_location_;
if (location.IsValid() &&
location.beg_pos > beg_pos && location.end_pos < end_pos) {
ReportMessageAt(location, strict_mode_violation_type_, NULL);
*ok = false;
}
}
void PreParser::StrictModeIdentifierViolation(i::Scanner::Location location,
const char* eval_args_type,
Identifier identifier,
bool* ok) {
const char* type = eval_args_type;
if (identifier.IsFutureReserved()) {
type = "reserved_word";
} else if (identifier.IsFutureStrictReserved()) {
type = "strict_reserved_word";
}
if (!is_classic_mode()) {
ReportMessageAt(location, type, NULL);
*ok = false;
return;
}
strict_mode_violation_location_ = location;
strict_mode_violation_type_ = type;
}
PreParser::Identifier PreParser::ParseIdentifierName(bool* ok) {
i::Token::Value next = Next();
if (i::Token::IsKeyword(next)) {
int pos = scanner_->location().beg_pos;
const char* keyword = i::Token::String(next);
log_->LogAsciiSymbol(pos, i::Vector<const char>(keyword,
i::StrLength(keyword)));
return Identifier::Default();
}
if (next == i::Token::IDENTIFIER ||
next == i::Token::FUTURE_RESERVED_WORD ||
next == i::Token::FUTURE_STRICT_RESERVED_WORD) {
return GetIdentifierSymbol();
}
*ok = false;
return Identifier::Default();
}
#undef CHECK_OK
// This function reads an identifier and determines whether or not it
// is 'get' or 'set'.
PreParser::Identifier PreParser::ParseIdentifierNameOrGetOrSet(bool* is_get,
bool* is_set,
bool* ok) {
Identifier result = ParseIdentifierName(ok);
if (!*ok) return Identifier::Default();
if (scanner_->is_literal_ascii() &&
scanner_->literal_length() == 3) {
const char* token = scanner_->literal_ascii_string().start();
*is_get = strncmp(token, "get", 3) == 0;
*is_set = !*is_get && strncmp(token, "set", 3) == 0;
}
return result;
}
bool PreParser::peek_any_identifier() {
i::Token::Value next = peek();
return next == i::Token::IDENTIFIER ||
next == i::Token::FUTURE_RESERVED_WORD ||
next == i::Token::FUTURE_STRICT_RESERVED_WORD;
}
int DuplicateFinder::AddAsciiSymbol(i::Vector<const char> key, int value) {
return AddSymbol(i::Vector<const byte>::cast(key), true, value);
}
int DuplicateFinder::AddUtf16Symbol(i::Vector<const uint16_t> key, int value) {
return AddSymbol(i::Vector<const byte>::cast(key), false, value);
}
int DuplicateFinder::AddSymbol(i::Vector<const byte> key,
bool is_ascii,
int value) {
uint32_t hash = Hash(key, is_ascii);
byte* encoding = BackupKey(key, is_ascii);
i::HashMap::Entry* entry = map_.Lookup(encoding, hash, true);
int old_value = static_cast<int>(reinterpret_cast<intptr_t>(entry->value));
entry->value =
reinterpret_cast<void*>(static_cast<intptr_t>(value | old_value));
return old_value;
}
int DuplicateFinder::AddNumber(i::Vector<const char> key, int value) {
ASSERT(key.length() > 0);
// Quick check for already being in canonical form.
if (IsNumberCanonical(key)) {
return AddAsciiSymbol(key, value);
}
int flags = i::ALLOW_HEX | i::ALLOW_OCTALS;
double double_value = StringToDouble(unicode_constants_, key, flags, 0.0);
int length;
const char* string;
if (!isfinite(double_value)) {
string = "Infinity";
length = 8; // strlen("Infinity");
} else {
string = DoubleToCString(double_value,
i::Vector<char>(number_buffer_, kBufferSize));
length = i::StrLength(string);
}
return AddSymbol(i::Vector<const byte>(reinterpret_cast<const byte*>(string),
length), true, value);
}
bool DuplicateFinder::IsNumberCanonical(i::Vector<const char> number) {
// Test for a safe approximation of number literals that are already
// in canonical form: max 15 digits, no leading zeroes, except an
// integer part that is a single zero, and no trailing zeros below
// the decimal point.
int pos = 0;
int length = number.length();
if (number.length() > 15) return false;
if (number[pos] == '0') {
pos++;
} else {
while (pos < length &&
static_cast<unsigned>(number[pos] - '0') <= ('9' - '0')) pos++;
}
if (length == pos) return true;
if (number[pos] != '.') return false;
pos++;
bool invalid_last_digit = true;
while (pos < length) {
byte digit = number[pos] - '0';
if (digit > '9' - '0') return false;
invalid_last_digit = (digit == 0);
pos++;
}
return !invalid_last_digit;
}
uint32_t DuplicateFinder::Hash(i::Vector<const byte> key, bool is_ascii) {
// Primitive hash function, almost identical to the one used
// for strings (except that it's seeded by the length and ASCII-ness).
int length = key.length();
uint32_t hash = (length << 1) | (is_ascii ? 1 : 0) ;
for (int i = 0; i < length; i++) {
uint32_t c = key[i];
hash = (hash + c) * 1025;
hash ^= (hash >> 6);
}
return hash;
}
bool DuplicateFinder::Match(void* first, void* second) {
// Decode lengths.
// Length + ASCII-bit is encoded as base 128, most significant heptet first,
// with a 8th bit being non-zero while there are more heptets.
// The value encodes the number of bytes following, and whether the original
// was ASCII.
byte* s1 = reinterpret_cast<byte*>(first);
byte* s2 = reinterpret_cast<byte*>(second);
uint32_t length_ascii_field = 0;
byte c1;
do {
c1 = *s1;
if (c1 != *s2) return false;
length_ascii_field = (length_ascii_field << 7) | (c1 & 0x7f);
s1++;
s2++;
} while ((c1 & 0x80) != 0);
int length = static_cast<int>(length_ascii_field >> 1);
return memcmp(s1, s2, length) == 0;
}
byte* DuplicateFinder::BackupKey(i::Vector<const byte> bytes,
bool is_ascii) {
uint32_t ascii_length = (bytes.length() << 1) | (is_ascii ? 1 : 0);
backing_store_.StartSequence();
// Emit ascii_length as base-128 encoded number, with the 7th bit set
// on the byte of every heptet except the last, least significant, one.
if (ascii_length >= (1 << 7)) {
if (ascii_length >= (1 << 14)) {
if (ascii_length >= (1 << 21)) {
if (ascii_length >= (1 << 28)) {
backing_store_.Add(static_cast<byte>((ascii_length >> 28) | 0x80));
}
backing_store_.Add(static_cast<byte>((ascii_length >> 21) | 0x80u));
}
backing_store_.Add(static_cast<byte>((ascii_length >> 14) | 0x80u));
}
backing_store_.Add(static_cast<byte>((ascii_length >> 7) | 0x80u));
}
backing_store_.Add(static_cast<byte>(ascii_length & 0x7f));
backing_store_.AddBlock(bytes);
return backing_store_.EndSequence().start();
}
} } // v8::preparser