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v8/src/preparser.h

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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_PREPARSER_H
#define V8_PREPARSER_H
#include "src/v8.h"
#include "src/func-name-inferrer.h"
#include "src/hashmap.h"
#include "src/scanner.h"
#include "src/scopes.h"
#include "src/token.h"
namespace v8 {
namespace internal {
// Common base class shared between parser and pre-parser. Traits encapsulate
// the differences between Parser and PreParser:
// - Return types: For example, Parser functions return Expression* and
// PreParser functions return PreParserExpression.
// - Creating parse tree nodes: Parser generates an AST during the recursive
// descent. PreParser doesn't create a tree. Instead, it passes around minimal
// data objects (PreParserExpression, PreParserIdentifier etc.) which contain
// just enough data for the upper layer functions. PreParserFactory is
// responsible for creating these dummy objects. It provides a similar kind of
// interface as AstNodeFactory, so ParserBase doesn't need to care which one is
// used.
// - Miscellanous other tasks interleaved with the recursive descent. For
// example, Parser keeps track of which function literals should be marked as
// pretenured, and PreParser doesn't care.
// The traits are expected to contain the following typedefs:
// struct Traits {
// // In particular...
// struct Type {
// // Used by FunctionState and BlockState.
// typedef Scope;
// typedef GeneratorVariable;
// typedef Zone;
// // Return types for traversing functions.
// typedef Identifier;
// typedef Expression;
// typedef FunctionLiteral;
// typedef ObjectLiteralProperty;
// typedef Literal;
// typedef ExpressionList;
// typedef PropertyList;
// // For constructing objects returned by the traversing functions.
// typedef Factory;
// };
// // ...
// };
template <typename Traits>
class ParserBase : public Traits {
public:
// Shorten type names defined by Traits.
typedef typename Traits::Type::Expression ExpressionT;
typedef typename Traits::Type::Identifier IdentifierT;
ParserBase(Scanner* scanner, uintptr_t stack_limit,
v8::Extension* extension,
ParserRecorder* log,
typename Traits::Type::Zone* zone,
typename Traits::Type::Parser this_object)
: Traits(this_object),
parenthesized_function_(false),
scope_(NULL),
function_state_(NULL),
extension_(extension),
fni_(NULL),
log_(log),
mode_(PARSE_EAGERLY), // Lazy mode must be set explicitly.
scanner_(scanner),
stack_limit_(stack_limit),
stack_overflow_(false),
allow_lazy_(false),
allow_natives_syntax_(false),
allow_generators_(false),
allow_for_of_(false),
zone_(zone) { }
// Getters that indicate whether certain syntactical constructs are
// allowed to be parsed by this instance of the parser.
bool allow_lazy() const { return allow_lazy_; }
bool allow_natives_syntax() const { return allow_natives_syntax_; }
bool allow_generators() const { return allow_generators_; }
bool allow_for_of() const { return allow_for_of_; }
bool allow_modules() const { return scanner()->HarmonyModules(); }
bool allow_harmony_scoping() const { return scanner()->HarmonyScoping(); }
bool allow_harmony_numeric_literals() const {
return scanner()->HarmonyNumericLiterals();
}
// Setters that determine whether certain syntactical constructs are
// allowed to be parsed by this instance of the parser.
void set_allow_lazy(bool allow) { allow_lazy_ = allow; }
void set_allow_natives_syntax(bool allow) { allow_natives_syntax_ = allow; }
void set_allow_generators(bool allow) { allow_generators_ = allow; }
void set_allow_for_of(bool allow) { allow_for_of_ = allow; }
void set_allow_modules(bool allow) { scanner()->SetHarmonyModules(allow); }
void set_allow_harmony_scoping(bool allow) {
scanner()->SetHarmonyScoping(allow);
}
void set_allow_harmony_numeric_literals(bool allow) {
scanner()->SetHarmonyNumericLiterals(allow);
}
protected:
enum AllowEvalOrArgumentsAsIdentifier {
kAllowEvalOrArguments,
kDontAllowEvalOrArguments
};
enum Mode {
PARSE_LAZILY,
PARSE_EAGERLY
};
// ---------------------------------------------------------------------------
// FunctionState and BlockState together implement the parser's scope stack.
// The parser's current scope is in scope_. BlockState and FunctionState
// constructors push on the scope stack and the destructors pop. They are also
// used to hold the parser's per-function and per-block state.
class BlockState BASE_EMBEDDED {
public:
BlockState(typename Traits::Type::Scope** scope_stack,
typename Traits::Type::Scope* scope)
: scope_stack_(scope_stack),
outer_scope_(*scope_stack),
scope_(scope) {
*scope_stack_ = scope_;
}
~BlockState() { *scope_stack_ = outer_scope_; }
private:
typename Traits::Type::Scope** scope_stack_;
typename Traits::Type::Scope* outer_scope_;
typename Traits::Type::Scope* scope_;
};
class FunctionState BASE_EMBEDDED {
public:
FunctionState(
FunctionState** function_state_stack,
typename Traits::Type::Scope** scope_stack,
typename Traits::Type::Scope* scope,
typename Traits::Type::Zone* zone = NULL);
~FunctionState();
int NextMaterializedLiteralIndex() {
return next_materialized_literal_index_++;
}
int materialized_literal_count() {
return next_materialized_literal_index_ - JSFunction::kLiteralsPrefixSize;
}
int NextHandlerIndex() { return next_handler_index_++; }
int handler_count() { return next_handler_index_; }
void AddProperty() { expected_property_count_++; }
int expected_property_count() { return expected_property_count_; }
void set_is_generator(bool is_generator) { is_generator_ = is_generator; }
bool is_generator() const { return is_generator_; }
void set_generator_object_variable(
typename Traits::Type::GeneratorVariable* variable) {
ASSERT(variable != NULL);
ASSERT(!is_generator());
generator_object_variable_ = variable;
is_generator_ = true;
}
typename Traits::Type::GeneratorVariable* generator_object_variable()
const {
return generator_object_variable_;
}
typename Traits::Type::Factory* factory() { return &factory_; }
private:
// Used to assign an index to each literal that needs materialization in
// the function. Includes regexp literals, and boilerplate for object and
// array literals.
int next_materialized_literal_index_;
// Used to assign a per-function index to try and catch handlers.
int next_handler_index_;
// Properties count estimation.
int expected_property_count_;
// Whether the function is a generator.
bool is_generator_;
// For generators, this variable may hold the generator object. It variable
// is used by yield expressions and return statements. It is not necessary
// for generator functions to have this variable set.
Variable* generator_object_variable_;
FunctionState** function_state_stack_;
FunctionState* outer_function_state_;
typename Traits::Type::Scope** scope_stack_;
typename Traits::Type::Scope* outer_scope_;
int saved_ast_node_id_; // Only used by ParserTraits.
typename Traits::Type::Zone* extra_param_;
typename Traits::Type::Factory factory_;
friend class ParserTraits;
};
class ParsingModeScope BASE_EMBEDDED {
public:
ParsingModeScope(ParserBase* parser, Mode mode)
: parser_(parser),
old_mode_(parser->mode()) {
parser_->mode_ = mode;
}
~ParsingModeScope() {
parser_->mode_ = old_mode_;
}
private:
ParserBase* parser_;
Mode old_mode_;
};
Scanner* scanner() const { return scanner_; }
int position() { return scanner_->location().beg_pos; }
int peek_position() { return scanner_->peek_location().beg_pos; }
bool stack_overflow() const { return stack_overflow_; }
void set_stack_overflow() { stack_overflow_ = true; }
Mode mode() const { return mode_; }
typename Traits::Type::Zone* zone() const { return zone_; }
INLINE(Token::Value peek()) {
if (stack_overflow_) return Token::ILLEGAL;
return scanner()->peek();
}
INLINE(Token::Value Next()) {
if (stack_overflow_) return Token::ILLEGAL;
{
int marker;
if (reinterpret_cast<uintptr_t>(&marker) < stack_limit_) {
// Any further calls to Next or peek will return the illegal token.
// The current call must return the next token, which might already
// have been peek'ed.
stack_overflow_ = true;
}
}
return scanner()->Next();
}
void Consume(Token::Value token) {
Token::Value next = Next();
USE(next);
USE(token);
ASSERT(next == token);
}
bool Check(Token::Value token) {
Token::Value next = peek();
if (next == token) {
Consume(next);
return true;
}
return false;
}
void Expect(Token::Value token, bool* ok) {
Token::Value next = Next();
if (next != token) {
ReportUnexpectedToken(next);
*ok = false;
}
}
void ExpectSemicolon(bool* ok) {
// Check for automatic semicolon insertion according to
// the rules given in ECMA-262, section 7.9, page 21.
Token::Value tok = peek();
if (tok == Token::SEMICOLON) {
Next();
return;
}
if (scanner()->HasAnyLineTerminatorBeforeNext() ||
tok == Token::RBRACE ||
tok == Token::EOS) {
return;
}
Expect(Token::SEMICOLON, ok);
}
bool peek_any_identifier() {
Token::Value next = peek();
return next == Token::IDENTIFIER ||
next == Token::FUTURE_RESERVED_WORD ||
next == Token::FUTURE_STRICT_RESERVED_WORD ||
next == Token::YIELD;
}
bool CheckContextualKeyword(Vector<const char> keyword) {
if (peek() == Token::IDENTIFIER &&
scanner()->is_next_contextual_keyword(keyword)) {
Consume(Token::IDENTIFIER);
return true;
}
return false;
}
void ExpectContextualKeyword(Vector<const char> keyword, bool* ok) {
Expect(Token::IDENTIFIER, ok);
if (!*ok) return;
if (!scanner()->is_literal_contextual_keyword(keyword)) {
ReportUnexpectedToken(scanner()->current_token());
*ok = false;
}
}
// Checks whether an octal literal was last seen between beg_pos and end_pos.
// If so, reports an error. Only called for strict mode.
void CheckOctalLiteral(int beg_pos, int end_pos, bool* ok) {
Scanner::Location octal = scanner()->octal_position();
if (octal.IsValid() && beg_pos <= octal.beg_pos &&
octal.end_pos <= end_pos) {
ReportMessageAt(octal, "strict_octal_literal");
scanner()->clear_octal_position();
*ok = false;
}
}
// Determine precedence of given token.
static int Precedence(Token::Value token, bool accept_IN) {
if (token == Token::IN && !accept_IN)
return 0; // 0 precedence will terminate binary expression parsing
return Token::Precedence(token);
}
typename Traits::Type::Factory* factory() {
return function_state_->factory();
}
StrictMode strict_mode() { return scope_->strict_mode(); }
bool is_generator() const { return function_state_->is_generator(); }
// Report syntax errors.
void ReportMessage(const char* message, const char* arg = NULL,
bool is_reference_error = false) {
Scanner::Location source_location = scanner()->location();
Traits::ReportMessageAt(source_location, message, arg, is_reference_error);
}
void ReportMessageAt(Scanner::Location location, const char* message,
bool is_reference_error = false) {
Traits::ReportMessageAt(location, message, NULL, is_reference_error);
}
void ReportUnexpectedToken(Token::Value token);
// Recursive descent functions:
// Parses an identifier that is valid for the current scope, in particular it
// fails on strict mode future reserved keywords in a strict scope. If
// allow_eval_or_arguments is kAllowEvalOrArguments, we allow "eval" or
// "arguments" as identifier even in strict mode (this is needed in cases like
// "var foo = eval;").
IdentifierT ParseIdentifier(
AllowEvalOrArgumentsAsIdentifier,
bool* ok);
// Parses an identifier or a strict mode future reserved word, and indicate
// whether it is strict mode future reserved.
IdentifierT ParseIdentifierOrStrictReservedWord(
bool* is_strict_reserved,
bool* ok);
IdentifierT ParseIdentifierName(bool* ok);
// Parses an identifier and determines whether or not it is 'get' or 'set'.
IdentifierT ParseIdentifierNameOrGetOrSet(bool* is_get,
bool* is_set,
bool* ok);
ExpressionT ParseRegExpLiteral(bool seen_equal, bool* ok);
ExpressionT ParsePrimaryExpression(bool* ok);
ExpressionT ParseExpression(bool accept_IN, bool* ok);
ExpressionT ParseArrayLiteral(bool* ok);
ExpressionT ParseObjectLiteral(bool* ok);
typename Traits::Type::ExpressionList ParseArguments(bool* ok);
ExpressionT ParseAssignmentExpression(bool accept_IN, bool* ok);
ExpressionT ParseYieldExpression(bool* ok);
ExpressionT ParseConditionalExpression(bool accept_IN, bool* ok);
ExpressionT ParseBinaryExpression(int prec, bool accept_IN, bool* ok);
ExpressionT ParseUnaryExpression(bool* ok);
ExpressionT ParsePostfixExpression(bool* ok);
ExpressionT ParseLeftHandSideExpression(bool* ok);
ExpressionT ParseMemberWithNewPrefixesExpression(bool* ok);
ExpressionT ParseMemberExpression(bool* ok);
ExpressionT ParseMemberExpressionContinuation(ExpressionT expression,
bool* ok);
// Checks if the expression is a valid reference expression (e.g., on the
// left-hand side of assignments). Although ruled out by ECMA as early errors,
// we allow calls for web compatibility and rewrite them to a runtime throw.
ExpressionT CheckAndRewriteReferenceExpression(
ExpressionT expression,
Scanner::Location location, const char* message, bool* ok);
// Used to detect duplicates in object literals. Each of the values
// kGetterProperty, kSetterProperty and kValueProperty represents
// a type of object literal property. When parsing a property, its
// type value is stored in the DuplicateFinder for the property name.
// Values are chosen so that having intersection bits means the there is
// an incompatibility.
// I.e., you can add a getter to a property that already has a setter, since
// kGetterProperty and kSetterProperty doesn't intersect, but not if it
// already has a getter or a value. Adding the getter to an existing
// setter will store the value (kGetterProperty | kSetterProperty), which
// is incompatible with adding any further properties.
enum PropertyKind {
kNone = 0,
// Bit patterns representing different object literal property types.
kGetterProperty = 1,
kSetterProperty = 2,
kValueProperty = 7,
// Helper constants.
kValueFlag = 4
};
// Validation per ECMA 262 - 11.1.5 "Object Initialiser".
class ObjectLiteralChecker {
public:
ObjectLiteralChecker(ParserBase* parser, StrictMode strict_mode)
: parser_(parser),
finder_(scanner()->unicode_cache()),
strict_mode_(strict_mode) { }
void CheckProperty(Token::Value property, PropertyKind type, bool* ok);
private:
ParserBase* parser() const { return parser_; }
Scanner* scanner() const { return parser_->scanner(); }
// Checks the type of conflict based on values coming from PropertyType.
bool HasConflict(PropertyKind type1, PropertyKind type2) {
return (type1 & type2) != 0;
}
bool IsDataDataConflict(PropertyKind type1, PropertyKind type2) {
return ((type1 & type2) & kValueFlag) != 0;
}
bool IsDataAccessorConflict(PropertyKind type1, PropertyKind type2) {
return ((type1 ^ type2) & kValueFlag) != 0;
}
bool IsAccessorAccessorConflict(PropertyKind type1, PropertyKind type2) {
return ((type1 | type2) & kValueFlag) == 0;
}
ParserBase* parser_;
DuplicateFinder finder_;
StrictMode strict_mode_;
};
// If true, the next (and immediately following) function literal is
// preceded by a parenthesis.
// Heuristically that means that the function will be called immediately,
// so never lazily compile it.
bool parenthesized_function_;
typename Traits::Type::Scope* scope_; // Scope stack.
FunctionState* function_state_; // Function state stack.
v8::Extension* extension_;
FuncNameInferrer* fni_;
ParserRecorder* log_;
Mode mode_;
private:
Scanner* scanner_;
uintptr_t stack_limit_;
bool stack_overflow_;
bool allow_lazy_;
bool allow_natives_syntax_;
bool allow_generators_;
bool allow_for_of_;
typename Traits::Type::Zone* zone_; // Only used by Parser.
};
class PreParserIdentifier {
public:
PreParserIdentifier() : type_(kUnknownIdentifier) {}
static PreParserIdentifier Default() {
return PreParserIdentifier(kUnknownIdentifier);
}
static PreParserIdentifier Eval() {
return PreParserIdentifier(kEvalIdentifier);
}
static PreParserIdentifier Arguments() {
return PreParserIdentifier(kArgumentsIdentifier);
}
static PreParserIdentifier FutureReserved() {
return PreParserIdentifier(kFutureReservedIdentifier);
}
static PreParserIdentifier FutureStrictReserved() {
return PreParserIdentifier(kFutureStrictReservedIdentifier);
}
static PreParserIdentifier Yield() {
return PreParserIdentifier(kYieldIdentifier);
}
bool IsEval() { return type_ == kEvalIdentifier; }
bool IsArguments() { return type_ == kArgumentsIdentifier; }
bool IsEvalOrArguments() { return type_ >= kEvalIdentifier; }
bool IsYield() { return type_ == kYieldIdentifier; }
bool IsFutureReserved() { return type_ == kFutureReservedIdentifier; }
bool IsFutureStrictReserved() {
return type_ == kFutureStrictReservedIdentifier;
}
bool IsValidStrictVariable() { return type_ == kUnknownIdentifier; }
private:
enum Type {
kUnknownIdentifier,
kFutureReservedIdentifier,
kFutureStrictReservedIdentifier,
kYieldIdentifier,
kEvalIdentifier,
kArgumentsIdentifier
};
explicit PreParserIdentifier(Type type) : type_(type) {}
Type type_;
friend class PreParserExpression;
};
// Bits 0 and 1 are used to identify the type of expression:
// If bit 0 is set, it's an identifier.
// if bit 1 is set, it's a string literal.
// If neither is set, it's no particular type, and both set isn't
// use yet.
class PreParserExpression {
public:
static PreParserExpression Default() {
return PreParserExpression(kUnknownExpression);
}
static PreParserExpression FromIdentifier(PreParserIdentifier id) {
return PreParserExpression(kIdentifierFlag |
(id.type_ << kIdentifierShift));
}
static PreParserExpression StringLiteral() {
return PreParserExpression(kUnknownStringLiteral);
}
static PreParserExpression UseStrictStringLiteral() {
return PreParserExpression(kUseStrictString);
}
static PreParserExpression This() {
return PreParserExpression(kThisExpression);
}
static PreParserExpression ThisProperty() {
return PreParserExpression(kThisPropertyExpression);
}
static PreParserExpression Property() {
return PreParserExpression(kPropertyExpression);
}
static PreParserExpression Call() {
return PreParserExpression(kCallExpression);
}
bool IsIdentifier() { return (code_ & kIdentifierFlag) != 0; }
PreParserIdentifier AsIdentifier() {
ASSERT(IsIdentifier());
return PreParserIdentifier(
static_cast<PreParserIdentifier::Type>(code_ >> kIdentifierShift));
}
bool IsStringLiteral() { return (code_ & kStringLiteralFlag) != 0; }
bool IsUseStrictLiteral() {
return (code_ & kStringLiteralMask) == kUseStrictString;
}
bool IsThis() { return code_ == kThisExpression; }
bool IsThisProperty() { return code_ == kThisPropertyExpression; }
bool IsProperty() {
return code_ == kPropertyExpression || code_ == kThisPropertyExpression;
}
bool IsCall() { return code_ == kCallExpression; }
bool IsValidReferenceExpression() {
return IsIdentifier() || IsProperty();
}
// At the moment PreParser doesn't track these expression types.
bool IsFunctionLiteral() const { return false; }
bool IsCallNew() const { return false; }
PreParserExpression AsFunctionLiteral() { return *this; }
// Dummy implementation for making expression->somefunc() work in both Parser
// and PreParser.
PreParserExpression* operator->() { return this; }
// More dummy implementations of things PreParser doesn't need to track:
void set_index(int index) {} // For YieldExpressions
void set_parenthesized() {}
private:
// Least significant 2 bits are used as flags. Bits 0 and 1 represent
// identifiers or strings literals, and are mutually exclusive, but can both
// be absent. If the expression is an identifier or a string literal, the
// other bits describe the type (see PreParserIdentifier::Type and string
// literal constants below).
enum {
kUnknownExpression = 0,
// Identifiers
kIdentifierFlag = 1, // Used to detect labels.
kIdentifierShift = 3,
kStringLiteralFlag = 2, // Used to detect directive prologue.
kUnknownStringLiteral = kStringLiteralFlag,
kUseStrictString = kStringLiteralFlag | 8,
kStringLiteralMask = kUseStrictString,
// Below here applies if neither identifier nor string literal. Reserve the
// 2 least significant bits for flags.
kThisExpression = 1 << 2,
kThisPropertyExpression = 2 << 2,
kPropertyExpression = 3 << 2,
kCallExpression = 4 << 2
};
explicit PreParserExpression(int expression_code) : code_(expression_code) {}
int code_;
};
// PreParserExpressionList doesn't actually store the expressions because
// PreParser doesn't need to.
class PreParserExpressionList {
public:
// These functions make list->Add(some_expression) work (and do nothing).
PreParserExpressionList() : length_(0) {}
PreParserExpressionList* operator->() { return this; }
void Add(PreParserExpression, void*) { ++length_; }
int length() const { return length_; }
private:
int length_;
};
class PreParserStatement {
public:
static PreParserStatement Default() {
return PreParserStatement(kUnknownStatement);
}
static PreParserStatement FunctionDeclaration() {
return PreParserStatement(kFunctionDeclaration);
}
// Creates expression statement from expression.
// Preserves being an unparenthesized string literal, possibly
// "use strict".
static PreParserStatement ExpressionStatement(
PreParserExpression expression) {
if (expression.IsUseStrictLiteral()) {
return PreParserStatement(kUseStrictExpressionStatement);
}
if (expression.IsStringLiteral()) {
return PreParserStatement(kStringLiteralExpressionStatement);
}
return Default();
}
bool IsStringLiteral() {
return code_ == kStringLiteralExpressionStatement;
}
bool IsUseStrictLiteral() {
return code_ == kUseStrictExpressionStatement;
}
bool IsFunctionDeclaration() {
return code_ == kFunctionDeclaration;
}
private:
enum Type {
kUnknownStatement,
kStringLiteralExpressionStatement,
kUseStrictExpressionStatement,
kFunctionDeclaration
};
explicit PreParserStatement(Type code) : code_(code) {}
Type code_;
};
// PreParserStatementList doesn't actually store the statements because
// the PreParser does not need them.
class PreParserStatementList {
public:
// These functions make list->Add(some_expression) work as no-ops.
PreParserStatementList() {}
PreParserStatementList* operator->() { return this; }
void Add(PreParserStatement, void*) {}
};
class PreParserScope {
public:
explicit PreParserScope(PreParserScope* outer_scope, ScopeType scope_type)
: scope_type_(scope_type) {
strict_mode_ = outer_scope ? outer_scope->strict_mode() : SLOPPY;
}
ScopeType type() { return scope_type_; }
StrictMode strict_mode() const { return strict_mode_; }
void SetStrictMode(StrictMode strict_mode) { strict_mode_ = strict_mode; }
private:
ScopeType scope_type_;
StrictMode strict_mode_;
};
class PreParserFactory {
public:
explicit PreParserFactory(void* extra_param) {}
PreParserExpression NewLiteral(PreParserIdentifier identifier,
int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewNumberLiteral(double number,
int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewRegExpLiteral(PreParserIdentifier js_pattern,
PreParserIdentifier js_flags,
int literal_index,
int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewArrayLiteral(PreParserExpressionList values,
int literal_index,
int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewObjectLiteralProperty(bool is_getter,
PreParserExpression value,
int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewObjectLiteralProperty(PreParserExpression key,
PreParserExpression value) {
return PreParserExpression::Default();
}
PreParserExpression NewObjectLiteral(PreParserExpressionList properties,
int literal_index,
int boilerplate_properties,
bool has_function,
int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewVariableProxy(void* generator_variable) {
return PreParserExpression::Default();
}
PreParserExpression NewProperty(PreParserExpression obj,
PreParserExpression key,
int pos) {
if (obj.IsThis()) {
return PreParserExpression::ThisProperty();
}
return PreParserExpression::Property();
}
PreParserExpression NewUnaryOperation(Token::Value op,
PreParserExpression expression,
int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewBinaryOperation(Token::Value op,
PreParserExpression left,
PreParserExpression right, int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewCompareOperation(Token::Value op,
PreParserExpression left,
PreParserExpression right, int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewAssignment(Token::Value op,
PreParserExpression left,
PreParserExpression right,
int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewYield(PreParserExpression generator_object,
PreParserExpression expression,
Yield::Kind yield_kind,
int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewConditional(PreParserExpression condition,
PreParserExpression then_expression,
PreParserExpression else_expression,
int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewCountOperation(Token::Value op,
bool is_prefix,
PreParserExpression expression,
int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewCall(PreParserExpression expression,
PreParserExpressionList arguments,
int pos) {
return PreParserExpression::Call();
}
PreParserExpression NewCallNew(PreParserExpression expression,
PreParserExpressionList arguments,
int pos) {
return PreParserExpression::Default();
}
};
class PreParser;
class PreParserTraits {
public:
struct Type {
// TODO(marja): To be removed. The Traits object should contain all the data
// it needs.
typedef PreParser* Parser;
// Used by FunctionState and BlockState.
typedef PreParserScope Scope;
// PreParser doesn't need to store generator variables.
typedef void GeneratorVariable;
// No interaction with Zones.
typedef void Zone;
// Return types for traversing functions.
typedef PreParserIdentifier Identifier;
typedef PreParserExpression Expression;
typedef PreParserExpression YieldExpression;
typedef PreParserExpression FunctionLiteral;
typedef PreParserExpression ObjectLiteralProperty;
typedef PreParserExpression Literal;
typedef PreParserExpressionList ExpressionList;
typedef PreParserExpressionList PropertyList;
typedef PreParserStatementList StatementList;
// For constructing objects returned by the traversing functions.
typedef PreParserFactory Factory;
};
explicit PreParserTraits(PreParser* pre_parser) : pre_parser_(pre_parser) {}
// Custom operations executed when FunctionStates are created and
// destructed. (The PreParser doesn't need to do anything.)
template<typename FunctionState>
static void SetUpFunctionState(FunctionState* function_state, void*) {}
template<typename FunctionState>
static void TearDownFunctionState(FunctionState* function_state, void*) {}
// Helper functions for recursive descent.
static bool IsEvalOrArguments(PreParserIdentifier identifier) {
return identifier.IsEvalOrArguments();
}
// Returns true if the expression is of type "this.foo".
static bool IsThisProperty(PreParserExpression expression) {
return expression.IsThisProperty();
}
static bool IsIdentifier(PreParserExpression expression) {
return expression.IsIdentifier();
}
static PreParserIdentifier AsIdentifier(PreParserExpression expression) {
return expression.AsIdentifier();
}
static bool IsBoilerplateProperty(PreParserExpression property) {
// PreParser doesn't count boilerplate properties.
return false;
}
static bool IsArrayIndex(PreParserIdentifier string, uint32_t* index) {
return false;
}
// Functions for encapsulating the differences between parsing and preparsing;
// operations interleaved with the recursive descent.
static void PushLiteralName(FuncNameInferrer* fni, PreParserIdentifier id) {
// PreParser should not use FuncNameInferrer.
UNREACHABLE();
}
static void PushPropertyName(FuncNameInferrer* fni,
PreParserExpression expression) {
// PreParser should not use FuncNameInferrer.
UNREACHABLE();
}
static void CheckFunctionLiteralInsideTopLevelObjectLiteral(
PreParserScope* scope, PreParserExpression value, bool* has_function) {}
static void CheckAssigningFunctionLiteralToProperty(
PreParserExpression left, PreParserExpression right) {}
// PreParser doesn't need to keep track of eval calls.
static void CheckPossibleEvalCall(PreParserExpression expression,
PreParserScope* scope) {}
static PreParserExpression MarkExpressionAsLValue(
PreParserExpression expression) {
// TODO(marja): To be able to produce the same errors, the preparser needs
// to start tracking which expressions are variables and which are lvalues.
return expression;
}
bool ShortcutNumericLiteralBinaryExpression(PreParserExpression* x,
PreParserExpression y,
Token::Value op,
int pos,
PreParserFactory* factory) {
return false;
}
PreParserExpression BuildUnaryExpression(PreParserExpression expression,
Token::Value op, int pos,
PreParserFactory* factory) {
return PreParserExpression::Default();
}
PreParserExpression NewThrowReferenceError(const char* type, int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewThrowSyntaxError(
const char* type, Handle<Object> arg, int pos) {
return PreParserExpression::Default();
}
PreParserExpression NewThrowTypeError(
const char* type, Handle<Object> arg, int pos) {
return PreParserExpression::Default();
}
// Reporting errors.
void ReportMessageAt(Scanner::Location location,
const char* message,
const char* arg = NULL,
bool is_reference_error = false);
void ReportMessageAt(int start_pos,
int end_pos,
const char* message,
const char* arg = NULL,
bool is_reference_error = false);
// "null" return type creators.
static PreParserIdentifier EmptyIdentifier() {
return PreParserIdentifier::Default();
}
static PreParserExpression EmptyExpression() {
return PreParserExpression::Default();
}
static PreParserExpression EmptyLiteral() {
return PreParserExpression::Default();
}
static PreParserExpressionList NullExpressionList() {
return PreParserExpressionList();
}
// Odd-ball literal creators.
static PreParserExpression GetLiteralTheHole(int position,
PreParserFactory* factory) {
return PreParserExpression::Default();
}
// Producing data during the recursive descent.
PreParserIdentifier GetSymbol(Scanner* scanner);
static PreParserIdentifier NextLiteralString(Scanner* scanner,
PretenureFlag tenured) {
return PreParserIdentifier::Default();
}
static PreParserExpression ThisExpression(PreParserScope* scope,
PreParserFactory* factory) {
return PreParserExpression::This();
}
static PreParserExpression ExpressionFromLiteral(
Token::Value token, int pos, Scanner* scanner,
PreParserFactory* factory) {
return PreParserExpression::Default();
}
static PreParserExpression ExpressionFromIdentifier(
PreParserIdentifier name, int pos, PreParserScope* scope,
PreParserFactory* factory) {
return PreParserExpression::FromIdentifier(name);
}
PreParserExpression ExpressionFromString(int pos,
Scanner* scanner,
PreParserFactory* factory = NULL);
static PreParserExpressionList NewExpressionList(int size, void* zone) {
return PreParserExpressionList();
}
static PreParserStatementList NewStatementList(int size, void* zone) {
return PreParserStatementList();
}
static PreParserExpressionList NewPropertyList(int size, void* zone) {
return PreParserExpressionList();
}
// Temporary glue; these functions will move to ParserBase.
PreParserExpression ParseV8Intrinsic(bool* ok);
PreParserExpression ParseFunctionLiteral(
PreParserIdentifier name,
Scanner::Location function_name_location,
bool name_is_strict_reserved,
bool is_generator,
int function_token_position,
FunctionLiteral::FunctionType type,
FunctionLiteral::ArityRestriction arity_restriction,
bool* ok);
private:
PreParser* pre_parser_;
};
// Preparsing checks a JavaScript program and emits preparse-data that helps
// a later parsing to be faster.
// See preparse-data-format.h for the data format.
// 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.
class PreParser : public ParserBase<PreParserTraits> {
public:
typedef PreParserIdentifier Identifier;
typedef PreParserExpression Expression;
typedef PreParserStatement Statement;
enum PreParseResult {
kPreParseStackOverflow,
kPreParseSuccess
};
PreParser(Scanner* scanner, ParserRecorder* log, uintptr_t stack_limit)
: ParserBase<PreParserTraits>(scanner, stack_limit, NULL, log, NULL,
this) {}
// Pre-parse the program from the character stream; returns true on
// success (even if parsing failed, the pre-parse data successfully
// captured the syntax error), and false if a stack-overflow happened
// during parsing.
PreParseResult PreParseProgram() {
PreParserScope scope(scope_, GLOBAL_SCOPE);
FunctionState top_scope(&function_state_, &scope_, &scope, NULL);
bool ok = true;
int start_position = scanner()->peek_location().beg_pos;
ParseSourceElements(Token::EOS, &ok);
if (stack_overflow()) return kPreParseStackOverflow;
if (!ok) {
ReportUnexpectedToken(scanner()->current_token());
} else if (scope_->strict_mode() == STRICT) {
CheckOctalLiteral(start_position, scanner()->location().end_pos, &ok);
}
return kPreParseSuccess;
}
// Parses a single function literal, from the opening parentheses before
// parameters to the closing brace after the body.
// Returns a FunctionEntry describing the body of the function in enough
// detail that it can be lazily compiled.
// The scanner is expected to have matched the "function" or "function*"
// keyword and parameters, and have consumed the initial '{'.
// At return, unless an error occurred, the scanner is positioned before the
// the final '}'.
PreParseResult PreParseLazyFunction(StrictMode strict_mode,
bool is_generator,
ParserRecorder* log);
private:
friend class PreParserTraits;
// These types form an algebra over syntactic categories that is just
// rich enough to let us recognize and propagate the constructs that
// are either being counted in the preparser data, or is important
// to throw the correct syntax error exceptions.
enum VariableDeclarationContext {
kSourceElement,
kStatement,
kForStatement
};
// If a list of variable declarations includes any initializers.
enum VariableDeclarationProperties {
kHasInitializers,
kHasNoInitializers
};
enum SourceElements {
kUnknownSourceElements
};
// All ParseXXX functions take as the last argument an *ok parameter
// which is set to false if parsing failed; it is unchanged otherwise.
// By making the 'exception handling' explicit, we are forced to check
// for failure at the call sites.
Statement ParseSourceElement(bool* ok);
SourceElements ParseSourceElements(int end_token, bool* ok);
Statement ParseStatement(bool* ok);
Statement ParseFunctionDeclaration(bool* ok);
Statement ParseBlock(bool* ok);
Statement ParseVariableStatement(VariableDeclarationContext var_context,
bool* ok);
Statement ParseVariableDeclarations(VariableDeclarationContext var_context,
VariableDeclarationProperties* decl_props,
int* num_decl,
bool* ok);
Statement ParseExpressionOrLabelledStatement(bool* ok);
Statement ParseIfStatement(bool* ok);
Statement ParseContinueStatement(bool* ok);
Statement ParseBreakStatement(bool* ok);
Statement ParseReturnStatement(bool* ok);
Statement ParseWithStatement(bool* ok);
Statement ParseSwitchStatement(bool* ok);
Statement ParseDoWhileStatement(bool* ok);
Statement ParseWhileStatement(bool* ok);
Statement ParseForStatement(bool* ok);
Statement ParseThrowStatement(bool* ok);
Statement ParseTryStatement(bool* ok);
Statement ParseDebuggerStatement(bool* ok);
Expression ParseConditionalExpression(bool accept_IN, bool* ok);
Expression ParseObjectLiteral(bool* ok);
Expression ParseV8Intrinsic(bool* ok);
Expression ParseFunctionLiteral(
Identifier name,
Scanner::Location function_name_location,
bool name_is_strict_reserved,
bool is_generator,
int function_token_pos,
FunctionLiteral::FunctionType function_type,
FunctionLiteral::ArityRestriction arity_restriction,
bool* ok);
void ParseLazyFunctionLiteralBody(bool* ok);
bool CheckInOrOf(bool accept_OF);
};
template<class Traits>
ParserBase<Traits>::FunctionState::FunctionState(
FunctionState** function_state_stack,
typename Traits::Type::Scope** scope_stack,
typename Traits::Type::Scope* scope,
typename Traits::Type::Zone* extra_param)
: next_materialized_literal_index_(JSFunction::kLiteralsPrefixSize),
next_handler_index_(0),
expected_property_count_(0),
is_generator_(false),
generator_object_variable_(NULL),
function_state_stack_(function_state_stack),
outer_function_state_(*function_state_stack),
scope_stack_(scope_stack),
outer_scope_(*scope_stack),
saved_ast_node_id_(0),
extra_param_(extra_param),
factory_(extra_param) {
*scope_stack_ = scope;
*function_state_stack = this;
Traits::SetUpFunctionState(this, extra_param);
}
template<class Traits>
ParserBase<Traits>::FunctionState::~FunctionState() {
*scope_stack_ = outer_scope_;
*function_state_stack_ = outer_function_state_;
Traits::TearDownFunctionState(this, extra_param_);
}
template<class Traits>
void ParserBase<Traits>::ReportUnexpectedToken(Token::Value token) {
Scanner::Location source_location = scanner()->location();
// Four of the tokens are treated specially
switch (token) {
case Token::EOS:
return ReportMessageAt(source_location, "unexpected_eos");
case Token::NUMBER:
return ReportMessageAt(source_location, "unexpected_token_number");
case Token::STRING:
return ReportMessageAt(source_location, "unexpected_token_string");
case Token::IDENTIFIER:
return ReportMessageAt(source_location, "unexpected_token_identifier");
case Token::FUTURE_RESERVED_WORD:
return ReportMessageAt(source_location, "unexpected_reserved");
case Token::YIELD:
case Token::FUTURE_STRICT_RESERVED_WORD:
return ReportMessageAt(source_location, strict_mode() == SLOPPY
? "unexpected_token_identifier" : "unexpected_strict_reserved");
default:
const char* name = Token::String(token);
ASSERT(name != NULL);
Traits::ReportMessageAt(source_location, "unexpected_token", name);
}
}
template<class Traits>
typename ParserBase<Traits>::IdentifierT ParserBase<Traits>::ParseIdentifier(
AllowEvalOrArgumentsAsIdentifier allow_eval_or_arguments,
bool* ok) {
Token::Value next = Next();
if (next == Token::IDENTIFIER) {
IdentifierT name = this->GetSymbol(scanner());
if (allow_eval_or_arguments == kDontAllowEvalOrArguments &&
strict_mode() == STRICT && this->IsEvalOrArguments(name)) {
ReportMessage("strict_eval_arguments");
*ok = false;
}
return name;
} else if (strict_mode() == SLOPPY &&
(next == Token::FUTURE_STRICT_RESERVED_WORD ||
(next == Token::YIELD && !is_generator()))) {
return this->GetSymbol(scanner());
} else {
this->ReportUnexpectedToken(next);
*ok = false;
return Traits::EmptyIdentifier();
}
}
template <class Traits>
typename ParserBase<Traits>::IdentifierT ParserBase<
Traits>::ParseIdentifierOrStrictReservedWord(bool* is_strict_reserved,
bool* ok) {
Token::Value next = Next();
if (next == Token::IDENTIFIER) {
*is_strict_reserved = false;
} else if (next == Token::FUTURE_STRICT_RESERVED_WORD ||
(next == Token::YIELD && !this->is_generator())) {
*is_strict_reserved = true;
} else {
ReportUnexpectedToken(next);
*ok = false;
return Traits::EmptyIdentifier();
}
return this->GetSymbol(scanner());
}
template <class Traits>
typename ParserBase<Traits>::IdentifierT
ParserBase<Traits>::ParseIdentifierName(bool* ok) {
Token::Value next = Next();
if (next != Token::IDENTIFIER && next != Token::FUTURE_RESERVED_WORD &&
next != Token::FUTURE_STRICT_RESERVED_WORD && !Token::IsKeyword(next)) {
this->ReportUnexpectedToken(next);
*ok = false;
return Traits::EmptyIdentifier();
}
return this->GetSymbol(scanner());
}
template <class Traits>
typename ParserBase<Traits>::IdentifierT
ParserBase<Traits>::ParseIdentifierNameOrGetOrSet(bool* is_get,
bool* is_set,
bool* ok) {
IdentifierT result = ParseIdentifierName(ok);
if (!*ok) return Traits::EmptyIdentifier();
scanner()->IsGetOrSet(is_get, is_set);
return result;
}
template <class Traits>
typename ParserBase<Traits>::ExpressionT ParserBase<Traits>::ParseRegExpLiteral(
bool seen_equal, bool* ok) {
int pos = peek_position();
if (!scanner()->ScanRegExpPattern(seen_equal)) {
Next();
ReportMessage("unterminated_regexp");
*ok = false;
return Traits::EmptyExpression();
}
int literal_index = function_state_->NextMaterializedLiteralIndex();
IdentifierT js_pattern = this->NextLiteralString(scanner(), TENURED);
if (!scanner()->ScanRegExpFlags()) {
Next();
ReportMessage("invalid_regexp_flags");
*ok = false;
return Traits::EmptyExpression();
}
IdentifierT js_flags = this->NextLiteralString(scanner(), TENURED);
Next();
return factory()->NewRegExpLiteral(js_pattern, js_flags, literal_index, pos);
}
#define CHECK_OK ok); \
if (!*ok) return this->EmptyExpression(); \
((void)0
#define DUMMY ) // to make indentation work
#undef DUMMY
// Used in functions where the return type is not ExpressionT.
#define CHECK_OK_CUSTOM(x) ok); \
if (!*ok) return this->x(); \
((void)0
#define DUMMY ) // to make indentation work
#undef DUMMY
template <class Traits>
typename ParserBase<Traits>::ExpressionT
ParserBase<Traits>::ParsePrimaryExpression(bool* ok) {
// PrimaryExpression ::
// 'this'
// 'null'
// 'true'
// 'false'
// Identifier
// Number
// String
// ArrayLiteral
// ObjectLiteral
// RegExpLiteral
// '(' Expression ')'
int pos = peek_position();
ExpressionT result = this->EmptyExpression();
Token::Value token = peek();
switch (token) {
case Token::THIS: {
Consume(Token::THIS);
result = this->ThisExpression(scope_, factory());
break;
}
case Token::NULL_LITERAL:
case Token::TRUE_LITERAL:
case Token::FALSE_LITERAL:
case Token::NUMBER:
Next();
result = this->ExpressionFromLiteral(token, pos, scanner(), factory());
break;
case Token::IDENTIFIER:
case Token::YIELD:
case Token::FUTURE_STRICT_RESERVED_WORD: {
// Using eval or arguments in this context is OK even in strict mode.
IdentifierT name = ParseIdentifier(kAllowEvalOrArguments, CHECK_OK);
result = this->ExpressionFromIdentifier(name, pos, scope_, factory());
break;
}
case Token::STRING: {
Consume(Token::STRING);
result = this->ExpressionFromString(pos, scanner(), factory());
break;
}
case Token::ASSIGN_DIV:
result = this->ParseRegExpLiteral(true, CHECK_OK);
break;
case Token::DIV:
result = this->ParseRegExpLiteral(false, CHECK_OK);
break;
case Token::LBRACK:
result = this->ParseArrayLiteral(CHECK_OK);
break;
case Token::LBRACE:
result = this->ParseObjectLiteral(CHECK_OK);
break;
case Token::LPAREN:
Consume(Token::LPAREN);
// Heuristically try to detect immediately called functions before
// seeing the call parentheses.
parenthesized_function_ = (peek() == Token::FUNCTION);
result = this->ParseExpression(true, CHECK_OK);
Expect(Token::RPAREN, CHECK_OK);
break;
case Token::MOD:
if (allow_natives_syntax() || extension_ != NULL) {
result = this->ParseV8Intrinsic(CHECK_OK);
break;
}
// If we're not allowing special syntax we fall-through to the
// default case.
default: {
Next();
ReportUnexpectedToken(token);
*ok = false;
}
}
return result;
}
// Precedence = 1
template <class Traits>
typename ParserBase<Traits>::ExpressionT ParserBase<Traits>::ParseExpression(
bool accept_IN, bool* ok) {
// Expression ::
// AssignmentExpression
// Expression ',' AssignmentExpression
ExpressionT result = this->ParseAssignmentExpression(accept_IN, CHECK_OK);
while (peek() == Token::COMMA) {
Expect(Token::COMMA, CHECK_OK);
int pos = position();
ExpressionT right = this->ParseAssignmentExpression(accept_IN, CHECK_OK);
result = factory()->NewBinaryOperation(Token::COMMA, result, right, pos);
}
return result;
}
template <class Traits>
typename ParserBase<Traits>::ExpressionT ParserBase<Traits>::ParseArrayLiteral(
bool* ok) {
// ArrayLiteral ::
// '[' Expression? (',' Expression?)* ']'
int pos = peek_position();
typename Traits::Type::ExpressionList values =
this->NewExpressionList(4, zone_);
Expect(Token::LBRACK, CHECK_OK);
while (peek() != Token::RBRACK) {
ExpressionT elem = this->EmptyExpression();
if (peek() == Token::COMMA) {
elem = this->GetLiteralTheHole(peek_position(), factory());
} else {
elem = this->ParseAssignmentExpression(true, CHECK_OK);
}
values->Add(elem, zone_);
if (peek() != Token::RBRACK) {
Expect(Token::COMMA, CHECK_OK);
}
}
Expect(Token::RBRACK, CHECK_OK);
// Update the scope information before the pre-parsing bailout.
int literal_index = function_state_->NextMaterializedLiteralIndex();
return factory()->NewArrayLiteral(values, literal_index, pos);
}
template <class Traits>
typename ParserBase<Traits>::ExpressionT ParserBase<Traits>::ParseObjectLiteral(
bool* ok) {
// ObjectLiteral ::
// '{' ((
// ((IdentifierName | String | Number) ':' AssignmentExpression) |
// (('get' | 'set') (IdentifierName | String | Number) FunctionLiteral)
// ) ',')* '}'
// (Except that trailing comma is not required and not allowed.)
int pos = peek_position();
typename Traits::Type::PropertyList properties =
this->NewPropertyList(4, zone_);
int number_of_boilerplate_properties = 0;
bool has_function = false;
ObjectLiteralChecker checker(this, strict_mode());
Expect(Token::LBRACE, CHECK_OK);
while (peek() != Token::RBRACE) {
if (fni_ != NULL) fni_->Enter();
typename Traits::Type::Literal key = this->EmptyLiteral();
Token::Value next = peek();
int next_pos = peek_position();
switch (next) {
case Token::FUTURE_RESERVED_WORD:
case Token::FUTURE_STRICT_RESERVED_WORD:
case Token::IDENTIFIER: {
bool is_getter = false;
bool is_setter = false;
IdentifierT id =
ParseIdentifierNameOrGetOrSet(&is_getter, &is_setter, CHECK_OK);
if (fni_ != NULL) this->PushLiteralName(fni_, id);
if ((is_getter || is_setter) && peek() != Token::COLON) {
// Special handling of getter and setter syntax:
// { ... , get foo() { ... }, ... , set foo(v) { ... v ... } , ... }
// We have already read the "get" or "set" keyword.
Token::Value next = Next();
if (next != i::Token::IDENTIFIER &&
next != i::Token::FUTURE_RESERVED_WORD &&
next != i::Token::FUTURE_STRICT_RESERVED_WORD &&
next != i::Token::NUMBER &&
next != i::Token::STRING &&
!Token::IsKeyword(next)) {
ReportUnexpectedToken(next);
*ok = false;
return this->EmptyLiteral();
}
// Validate the property.
PropertyKind type = is_getter ? kGetterProperty : kSetterProperty;
checker.CheckProperty(next, type, CHECK_OK);
IdentifierT name = this->GetSymbol(scanner_);
typename Traits::Type::FunctionLiteral value =
this->ParseFunctionLiteral(
name, scanner()->location(),
false, // reserved words are allowed here
false, // not a generator
RelocInfo::kNoPosition, FunctionLiteral::ANONYMOUS_EXPRESSION,
is_getter ? FunctionLiteral::GETTER_ARITY
: FunctionLiteral::SETTER_ARITY,
CHECK_OK);
typename Traits::Type::ObjectLiteralProperty property =
factory()->NewObjectLiteralProperty(is_getter, value, next_pos);
if (this->IsBoilerplateProperty(property)) {
number_of_boilerplate_properties++;
}
properties->Add(property, zone());
if (peek() != Token::RBRACE) {
// Need {} because of the CHECK_OK macro.
Expect(Token::COMMA, CHECK_OK);
}
if (fni_ != NULL) {
fni_->Infer();
fni_->Leave();
}
continue; // restart the while
}
// Failed to parse as get/set property, so it's just a normal property
// (which might be called "get" or "set" or something else).
key = factory()->NewLiteral(id, next_pos);
break;
}
case Token::STRING: {
Consume(Token::STRING);
IdentifierT string = this->GetSymbol(scanner_);
if (fni_ != NULL) this->PushLiteralName(fni_, string);
uint32_t index;
if (this->IsArrayIndex(string, &index)) {
key = factory()->NewNumberLiteral(index, next_pos);
break;
}
key = factory()->NewLiteral(string, next_pos);
break;
}
case Token::NUMBER: {
Consume(Token::NUMBER);
key = this->ExpressionFromLiteral(Token::NUMBER, next_pos, scanner_,
factory());
break;
}
default:
if (Token::IsKeyword(next)) {
Consume(next);
IdentifierT string = this->GetSymbol(scanner_);
key = factory()->NewLiteral(string, next_pos);
} else {
Token::Value next = Next();
ReportUnexpectedToken(next);
*ok = false;
return this->EmptyLiteral();
}
}
// Validate the property
checker.CheckProperty(next, kValueProperty, CHECK_OK);
Expect(Token::COLON, CHECK_OK);
ExpressionT value = this->ParseAssignmentExpression(true, CHECK_OK);
typename Traits::Type::ObjectLiteralProperty property =
factory()->NewObjectLiteralProperty(key, value);
// Mark top-level object literals that contain function literals and
// pretenure the literal so it can be added as a constant function
// property. (Parser only.)
this->CheckFunctionLiteralInsideTopLevelObjectLiteral(scope_, value,
&has_function);
// Count CONSTANT or COMPUTED properties to maintain the enumeration order.
if (this->IsBoilerplateProperty(property)) {
number_of_boilerplate_properties++;
}
properties->Add(property, zone());
// TODO(1240767): Consider allowing trailing comma.
if (peek() != Token::RBRACE) {
// Need {} because of the CHECK_OK macro.
Expect(Token::COMMA, CHECK_OK);
}
if (fni_ != NULL) {
fni_->Infer();
fni_->Leave();
}
}
Expect(Token::RBRACE, CHECK_OK);
// Computation of literal_index must happen before pre parse bailout.
int literal_index = function_state_->NextMaterializedLiteralIndex();
return factory()->NewObjectLiteral(properties,
literal_index,
number_of_boilerplate_properties,
has_function,
pos);
}
template <class Traits>
typename Traits::Type::ExpressionList ParserBase<Traits>::ParseArguments(
bool* ok) {
// Arguments ::
// '(' (AssignmentExpression)*[','] ')'
typename Traits::Type::ExpressionList result =
this->NewExpressionList(4, zone_);
Expect(Token::LPAREN, CHECK_OK_CUSTOM(NullExpressionList));
bool done = (peek() == Token::RPAREN);
while (!done) {
ExpressionT argument = this->ParseAssignmentExpression(
true, CHECK_OK_CUSTOM(NullExpressionList));
result->Add(argument, zone_);
if (result->length() > Code::kMaxArguments) {
ReportMessage("too_many_arguments");
*ok = false;
return this->NullExpressionList();
}
done = (peek() == Token::RPAREN);
if (!done) {
// Need {} because of the CHECK_OK_CUSTOM macro.
Expect(Token::COMMA, CHECK_OK_CUSTOM(NullExpressionList));
}
}
Expect(Token::RPAREN, CHECK_OK_CUSTOM(NullExpressionList));
return result;
}
// Precedence = 2
template <class Traits>
typename ParserBase<Traits>::ExpressionT
ParserBase<Traits>::ParseAssignmentExpression(bool accept_IN, bool* ok) {
// AssignmentExpression ::
// ConditionalExpression
// YieldExpression
// LeftHandSideExpression AssignmentOperator AssignmentExpression
Scanner::Location lhs_location = scanner()->peek_location();
if (peek() == Token::YIELD && is_generator()) {
return this->ParseYieldExpression(ok);
}
if (fni_ != NULL) fni_->Enter();
ExpressionT expression =
this->ParseConditionalExpression(accept_IN, CHECK_OK);
if (!Token::IsAssignmentOp(peek())) {
if (fni_ != NULL) fni_->Leave();
// Parsed conditional expression only (no assignment).
return expression;
}
expression = this->CheckAndRewriteReferenceExpression(
expression, lhs_location, "invalid_lhs_in_assignment", CHECK_OK);
expression = this->MarkExpressionAsLValue(expression);
Token::Value op = Next(); // Get assignment operator.
int pos = position();
ExpressionT right = this->ParseAssignmentExpression(accept_IN, CHECK_OK);
// TODO(1231235): We try to estimate the set of properties set by
// constructors. We define a new property whenever there is an
// assignment to a property of 'this'. We should probably only add
// properties if we haven't seen them before. Otherwise we'll
// probably overestimate the number of properties.
if (op == Token::ASSIGN && this->IsThisProperty(expression)) {
function_state_->AddProperty();
}
this->CheckAssigningFunctionLiteralToProperty(expression, right);
if (fni_ != NULL) {
// Check if the right hand side is a call to avoid inferring a
// name if we're dealing with "a = function(){...}();"-like
// expression.
if ((op == Token::INIT_VAR
|| op == Token::INIT_CONST_LEGACY
|| op == Token::ASSIGN)
&& (!right->IsCall() && !right->IsCallNew())) {
fni_->Infer();
} else {
fni_->RemoveLastFunction();
}
fni_->Leave();
}
return factory()->NewAssignment(op, expression, right, pos);
}
template <class Traits>
typename ParserBase<Traits>::ExpressionT
ParserBase<Traits>::ParseYieldExpression(bool* ok) {
// YieldExpression ::
// 'yield' '*'? AssignmentExpression
int pos = peek_position();
Expect(Token::YIELD, CHECK_OK);
Yield::Kind kind =
Check(Token::MUL) ? Yield::DELEGATING : Yield::SUSPEND;
ExpressionT generator_object =
factory()->NewVariableProxy(function_state_->generator_object_variable());
ExpressionT expression =
ParseAssignmentExpression(false, CHECK_OK);
typename Traits::Type::YieldExpression yield =
factory()->NewYield(generator_object, expression, kind, pos);
if (kind == Yield::DELEGATING) {
yield->set_index(function_state_->NextHandlerIndex());
}
return yield;
}
// Precedence = 3
template <class Traits>
typename ParserBase<Traits>::ExpressionT
ParserBase<Traits>::ParseConditionalExpression(bool accept_IN, bool* ok) {
// ConditionalExpression ::
// LogicalOrExpression
// LogicalOrExpression '?' AssignmentExpression ':' AssignmentExpression
int pos = peek_position();
// We start using the binary expression parser for prec >= 4 only!
ExpressionT expression = this->ParseBinaryExpression(4, accept_IN, CHECK_OK);
if (peek() != Token::CONDITIONAL) return expression;
Consume(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.
ExpressionT left = ParseAssignmentExpression(true, CHECK_OK);
Expect(Token::COLON, CHECK_OK);
ExpressionT right = ParseAssignmentExpression(accept_IN, CHECK_OK);
return factory()->NewConditional(expression, left, right, pos);
}
// Precedence >= 4
template <class Traits>
typename ParserBase<Traits>::ExpressionT
ParserBase<Traits>::ParseBinaryExpression(int prec, bool accept_IN, bool* ok) {
ASSERT(prec >= 4);
ExpressionT x = this->ParseUnaryExpression(CHECK_OK);
for (int prec1 = Precedence(peek(), accept_IN); prec1 >= prec; prec1--) {
// prec1 >= 4
while (Precedence(peek(), accept_IN) == prec1) {
Token::Value op = Next();
int pos = position();
ExpressionT y = ParseBinaryExpression(prec1 + 1, accept_IN, CHECK_OK);
if (this->ShortcutNumericLiteralBinaryExpression(&x, y, op, pos,
factory())) {
continue;
}
// For now we distinguish between comparisons and other binary
// operations. (We could combine the two and get rid of this
// code and AST node eventually.)
if (Token::IsCompareOp(op)) {
// We have a comparison.
Token::Value cmp = op;
switch (op) {
case Token::NE: cmp = Token::EQ; break;
case Token::NE_STRICT: cmp = Token::EQ_STRICT; break;
default: break;
}
x = factory()->NewCompareOperation(cmp, x, y, pos);
if (cmp != op) {
// The comparison was negated - add a NOT.
x = factory()->NewUnaryOperation(Token::NOT, x, pos);
}
} else {
// We have a "normal" binary operation.
x = factory()->NewBinaryOperation(op, x, y, pos);
}
}
}
return x;
}
template <class Traits>
typename ParserBase<Traits>::ExpressionT
ParserBase<Traits>::ParseUnaryExpression(bool* ok) {
// UnaryExpression ::
// PostfixExpression
// 'delete' UnaryExpression
// 'void' UnaryExpression
// 'typeof' UnaryExpression
// '++' UnaryExpression
// '--' UnaryExpression
// '+' UnaryExpression
// '-' UnaryExpression
// '~' UnaryExpression
// '!' UnaryExpression
Token::Value op = peek();
if (Token::IsUnaryOp(op)) {
op = Next();
int pos = position();
ExpressionT expression = ParseUnaryExpression(CHECK_OK);
// "delete identifier" is a syntax error in strict mode.
if (op == Token::DELETE && strict_mode() == STRICT &&
this->IsIdentifier(expression)) {
ReportMessage("strict_delete");
*ok = false;
return this->EmptyExpression();
}
// Allow Traits do rewrite the expression.
return this->BuildUnaryExpression(expression, op, pos, factory());
} else if (Token::IsCountOp(op)) {
op = Next();
Scanner::Location lhs_location = scanner()->peek_location();
ExpressionT expression = this->ParseUnaryExpression(CHECK_OK);
expression = this->CheckAndRewriteReferenceExpression(
expression, lhs_location, "invalid_lhs_in_prefix_op", CHECK_OK);
this->MarkExpressionAsLValue(expression);
return factory()->NewCountOperation(op,
true /* prefix */,
expression,
position());
} else {
return this->ParsePostfixExpression(ok);
}
}
template <class Traits>
typename ParserBase<Traits>::ExpressionT
ParserBase<Traits>::ParsePostfixExpression(bool* ok) {
// PostfixExpression ::
// LeftHandSideExpression ('++' | '--')?
Scanner::Location lhs_location = scanner()->peek_location();
ExpressionT expression = this->ParseLeftHandSideExpression(CHECK_OK);
if (!scanner()->HasAnyLineTerminatorBeforeNext() &&
Token::IsCountOp(peek())) {
expression = this->CheckAndRewriteReferenceExpression(
expression, lhs_location, "invalid_lhs_in_postfix_op", CHECK_OK);
expression = this->MarkExpressionAsLValue(expression);
Token::Value next = Next();
expression =
factory()->NewCountOperation(next,
false /* postfix */,
expression,
position());
}
return expression;
}
template <class Traits>
typename ParserBase<Traits>::ExpressionT
ParserBase<Traits>::ParseLeftHandSideExpression(bool* ok) {
// LeftHandSideExpression ::
// (NewExpression | MemberExpression) ...
ExpressionT result = this->ParseMemberWithNewPrefixesExpression(CHECK_OK);
while (true) {
switch (peek()) {
case Token::LBRACK: {
Consume(Token::LBRACK);
int pos = position();
ExpressionT index = ParseExpression(true, CHECK_OK);
result = factory()->NewProperty(result, index, pos);
Expect(Token::RBRACK, CHECK_OK);
break;
}
case Token::LPAREN: {
int pos;
if (scanner()->current_token() == Token::IDENTIFIER) {
// For call of an identifier we want to report position of
// the identifier as position of the call in the stack trace.
pos = position();
} else {
// For other kinds of calls we record position of the parenthesis as
// position of the call. Note that this is extremely important for
// expressions of the form function(){...}() for which call position
// should not point to the closing brace otherwise it will intersect
// with positions recorded for function literal and confuse debugger.
pos = peek_position();
// Also the trailing parenthesis are a hint that the function will
// be called immediately. If we happen to have parsed a preceding
// function literal eagerly, we can also compile it eagerly.
if (result->IsFunctionLiteral() && mode() == PARSE_EAGERLY) {
result->AsFunctionLiteral()->set_parenthesized();
}
}
typename Traits::Type::ExpressionList args = ParseArguments(CHECK_OK);
// Keep track of eval() calls since they disable all local variable
// optimizations.
// The calls that need special treatment are the
// direct eval calls. These calls are all of the form eval(...), with
// no explicit receiver.
// These calls are marked as potentially direct eval calls. Whether
// they are actually direct calls to eval is determined at run time.
this->CheckPossibleEvalCall(result, scope_);
result = factory()->NewCall(result, args, pos);
if (fni_ != NULL) fni_->RemoveLastFunction();
break;
}
case Token::PERIOD: {
Consume(Token::PERIOD);
int pos = position();
IdentifierT name = ParseIdentifierName(CHECK_OK);
result = factory()->NewProperty(
result, factory()->NewLiteral(name, pos), pos);
if (fni_ != NULL) this->PushLiteralName(fni_, name);
break;
}
default:
return result;
}
}
}
template <class Traits>
typename ParserBase<Traits>::ExpressionT
ParserBase<Traits>::ParseMemberWithNewPrefixesExpression(bool* ok) {
// NewExpression ::
// ('new')+ MemberExpression
// The grammar for new expressions is pretty warped. We can have several 'new'
// keywords following each other, and then a MemberExpression. When we see '('
// after the MemberExpression, it's associated with the rightmost unassociated
// 'new' to create a NewExpression with arguments. However, a NewExpression
// can also occur without arguments.
// Examples of new expression:
// new foo.bar().baz means (new (foo.bar)()).baz
// new foo()() means (new foo())()
// new new foo()() means (new (new foo())())
// new new foo means new (new foo)
// new new foo() means new (new foo())
// new new foo().bar().baz means (new (new foo()).bar()).baz
if (peek() == Token::NEW) {
Consume(Token::NEW);
int new_pos = position();
ExpressionT result = this->ParseMemberWithNewPrefixesExpression(CHECK_OK);
if (peek() == Token::LPAREN) {
// NewExpression with arguments.
typename Traits::Type::ExpressionList args =
this->ParseArguments(CHECK_OK);
result = factory()->NewCallNew(result, args, new_pos);
// The expression can still continue with . or [ after the arguments.
result = this->ParseMemberExpressionContinuation(result, CHECK_OK);
return result;
}
// NewExpression without arguments.
return factory()->NewCallNew(result, this->NewExpressionList(0, zone_),
new_pos);
}
// No 'new' keyword.
return this->ParseMemberExpression(ok);
}
template <class Traits>
typename ParserBase<Traits>::ExpressionT
ParserBase<Traits>::ParseMemberExpression(bool* ok) {
// MemberExpression ::
// (PrimaryExpression | FunctionLiteral)
// ('[' Expression ']' | '.' Identifier | Arguments)*
// The '[' Expression ']' and '.' Identifier parts are parsed by
// ParseMemberExpressionContinuation, and the Arguments part is parsed by the
// caller.
// Parse the initial primary or function expression.
ExpressionT result = this->EmptyExpression();
if (peek() == Token::FUNCTION) {
Consume(Token::FUNCTION);
int function_token_position = position();
bool is_generator = allow_generators() && Check(Token::MUL);
IdentifierT name = this->EmptyIdentifier();
bool is_strict_reserved_name = false;
Scanner::Location function_name_location = Scanner::Location::invalid();
FunctionLiteral::FunctionType function_type =
FunctionLiteral::ANONYMOUS_EXPRESSION;
if (peek_any_identifier()) {
name = ParseIdentifierOrStrictReservedWord(&is_strict_reserved_name,
CHECK_OK);
function_name_location = scanner()->location();
function_type = FunctionLiteral::NAMED_EXPRESSION;
}
result = this->ParseFunctionLiteral(name,
function_name_location,
is_strict_reserved_name,
is_generator,
function_token_position,
function_type,
FunctionLiteral::NORMAL_ARITY,
CHECK_OK);
} else {
result = ParsePrimaryExpression(CHECK_OK);
}
result = ParseMemberExpressionContinuation(result, CHECK_OK);
return result;
}
template <class Traits>
typename ParserBase<Traits>::ExpressionT
ParserBase<Traits>::ParseMemberExpressionContinuation(ExpressionT expression,
bool* ok) {
// Parses this part of MemberExpression:
// ('[' Expression ']' | '.' Identifier)*
while (true) {
switch (peek()) {
case Token::LBRACK: {
Consume(Token::LBRACK);
int pos = position();
ExpressionT index = this->ParseExpression(true, CHECK_OK);
expression = factory()->NewProperty(expression, index, pos);
if (fni_ != NULL) {
this->PushPropertyName(fni_, index);
}
Expect(Token::RBRACK, CHECK_OK);
break;
}
case Token::PERIOD: {
Consume(Token::PERIOD);
int pos = position();
IdentifierT name = ParseIdentifierName(CHECK_OK);
expression = factory()->NewProperty(
expression, factory()->NewLiteral(name, pos), pos);
if (fni_ != NULL) {
this->PushLiteralName(fni_, name);
}
break;
}
default:
return expression;
}
}
ASSERT(false);
return this->EmptyExpression();
}
template <typename Traits>
typename ParserBase<Traits>::ExpressionT
ParserBase<Traits>::CheckAndRewriteReferenceExpression(
ExpressionT expression,
Scanner::Location location, const char* message, bool* ok) {
if (strict_mode() == STRICT && this->IsIdentifier(expression) &&
this->IsEvalOrArguments(this->AsIdentifier(expression))) {
this->ReportMessageAt(location, "strict_eval_arguments", false);
*ok = false;
return this->EmptyExpression();
} else if (expression->IsValidReferenceExpression()) {
return expression;
} else if (expression->IsCall()) {
// If it is a call, make it a runtime error for legacy web compatibility.
// Rewrite `expr' to `expr[throw ReferenceError]'.
int pos = location.beg_pos;
ExpressionT error = this->NewThrowReferenceError(message, pos);
return factory()->NewProperty(expression, error, pos);
} else {
this->ReportMessageAt(location, message, true);
*ok = false;
return this->EmptyExpression();
}
}
#undef CHECK_OK
#undef CHECK_OK_CUSTOM
template <typename Traits>
void ParserBase<Traits>::ObjectLiteralChecker::CheckProperty(
Token::Value property,
PropertyKind type,
bool* ok) {
int old;
if (property == Token::NUMBER) {
old = scanner()->FindNumber(&finder_, type);
} else {
old = scanner()->FindSymbol(&finder_, type);
}
PropertyKind old_type = static_cast<PropertyKind>(old);
if (HasConflict(old_type, type)) {
if (IsDataDataConflict(old_type, type)) {
// Both are data properties.
if (strict_mode_ == SLOPPY) return;
parser()->ReportMessage("strict_duplicate_property");
} else if (IsDataAccessorConflict(old_type, type)) {
// Both a data and an accessor property with the same name.
parser()->ReportMessage("accessor_data_property");
} else {
ASSERT(IsAccessorAccessorConflict(old_type, type));
// Both accessors of the same type.
parser()->ReportMessage("accessor_get_set");
}
*ok = false;
}
}
} } // v8::internal
#endif // V8_PREPARSER_H
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