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// Copyright 2006-2008 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 "v8.h"
#include "ast.h"
#include "parser.h"
#include "scopes.h"
#include "string-stream.h"
namespace v8 {
namespace internal {
VariableProxySentinel VariableProxySentinel::this_proxy_(true);
VariableProxySentinel VariableProxySentinel::identifier_proxy_(false);
ValidLeftHandSideSentinel ValidLeftHandSideSentinel::instance_;
Property Property::this_property_(VariableProxySentinel::this_proxy(), NULL, 0);
Call Call::sentinel_(NULL, NULL, 0);
// ----------------------------------------------------------------------------
// All the Accept member functions for each syntax tree node type.
#define DECL_ACCEPT(type) \
void type::Accept(AstVisitor* v) { \
if (v->CheckStackOverflow()) return; \
v->Visit##type(this); \
}
AST_NODE_LIST(DECL_ACCEPT)
#undef DECL_ACCEPT
// ----------------------------------------------------------------------------
// Implementation of other node functionality.
Assignment* ExpressionStatement::StatementAsSimpleAssignment() {
return (expression()->AsAssignment() != NULL &&
!expression()->AsAssignment()->is_compound())
? expression()->AsAssignment()
: NULL;
}
CountOperation* ExpressionStatement::StatementAsCountOperation() {
return expression()->AsCountOperation();
}
VariableProxy::VariableProxy(Handle<String> name,
bool is_this,
bool inside_with)
: name_(name),
var_(NULL),
is_this_(is_this),
inside_with_(inside_with),
is_trivial_(false),
reaching_definitions_(NULL) {
// names must be canonicalized for fast equality checks
ASSERT(name->IsSymbol());
}
VariableProxy::VariableProxy(bool is_this)
: is_this_(is_this),
reaching_definitions_(NULL) {
}
void VariableProxy::BindTo(Variable* var) {
ASSERT(var_ == NULL); // must be bound only once
ASSERT(var != NULL); // must bind
ASSERT((is_this() && var->is_this()) || name_.is_identical_to(var->name()));
// Ideally CONST-ness should match. However, this is very hard to achieve
// because we don't know the exact semantics of conflicting (const and
// non-const) multiple variable declarations, const vars introduced via
// eval() etc. Const-ness and variable declarations are a complete mess
// in JS. Sigh...
var_ = var;
var->set_is_used(true);
}
Token::Value Assignment::binary_op() const {
switch (op_) {
case Token::ASSIGN_BIT_OR: return Token::BIT_OR;
case Token::ASSIGN_BIT_XOR: return Token::BIT_XOR;
case Token::ASSIGN_BIT_AND: return Token::BIT_AND;
case Token::ASSIGN_SHL: return Token::SHL;
case Token::ASSIGN_SAR: return Token::SAR;
case Token::ASSIGN_SHR: return Token::SHR;
case Token::ASSIGN_ADD: return Token::ADD;
case Token::ASSIGN_SUB: return Token::SUB;
case Token::ASSIGN_MUL: return Token::MUL;
case Token::ASSIGN_DIV: return Token::DIV;
case Token::ASSIGN_MOD: return Token::MOD;
default: UNREACHABLE();
}
return Token::ILLEGAL;
}
bool FunctionLiteral::AllowsLazyCompilation() {
return scope()->AllowsLazyCompilation();
}
ObjectLiteral::Property::Property(Literal* key, Expression* value) {
key_ = key;
value_ = value;
Object* k = *key->handle();
if (k->IsSymbol() && Heap::Proto_symbol()->Equals(String::cast(k))) {
kind_ = PROTOTYPE;
} else if (value_->AsMaterializedLiteral() != NULL) {
kind_ = MATERIALIZED_LITERAL;
} else if (value_->AsLiteral() != NULL) {
kind_ = CONSTANT;
} else {
kind_ = COMPUTED;
}
}
ObjectLiteral::Property::Property(bool is_getter, FunctionLiteral* value) {
key_ = new Literal(value->name());
value_ = value;
kind_ = is_getter ? GETTER : SETTER;
}
bool ObjectLiteral::Property::IsCompileTimeValue() {
return kind_ == CONSTANT ||
(kind_ == MATERIALIZED_LITERAL &&
CompileTimeValue::IsCompileTimeValue(value_));
}
void TargetCollector::AddTarget(BreakTarget* target) {
// Add the label to the collector, but discard duplicates.
int length = targets_->length();
for (int i = 0; i < length; i++) {
if (targets_->at(i) == target) return;
}
targets_->Add(target);
}
// ----------------------------------------------------------------------------
// Implementation of AstVisitor
void AstVisitor::VisitDeclarations(ZoneList<Declaration*>* declarations) {
for (int i = 0; i < declarations->length(); i++) {
Visit(declarations->at(i));
}
}
void AstVisitor::VisitStatements(ZoneList<Statement*>* statements) {
for (int i = 0; i < statements->length(); i++) {
Visit(statements->at(i));
}
}
void AstVisitor::VisitExpressions(ZoneList<Expression*>* expressions) {
for (int i = 0; i < expressions->length(); i++) {
// The variable statement visiting code may pass NULL expressions
// to this code. Maybe this should be handled by introducing an
// undefined expression or literal? Revisit this code if this
// changes
Expression* expression = expressions->at(i);
if (expression != NULL) Visit(expression);
}
}
// ----------------------------------------------------------------------------
// Regular expressions
#define MAKE_ACCEPT(Name) \
void* RegExp##Name::Accept(RegExpVisitor* visitor, void* data) { \
return visitor->Visit##Name(this, data); \
}
FOR_EACH_REG_EXP_TREE_TYPE(MAKE_ACCEPT)
#undef MAKE_ACCEPT
#define MAKE_TYPE_CASE(Name) \
RegExp##Name* RegExpTree::As##Name() { \
return NULL; \
} \
bool RegExpTree::Is##Name() { return false; }
FOR_EACH_REG_EXP_TREE_TYPE(MAKE_TYPE_CASE)
#undef MAKE_TYPE_CASE
#define MAKE_TYPE_CASE(Name) \
RegExp##Name* RegExp##Name::As##Name() { \
return this; \
} \
bool RegExp##Name::Is##Name() { return true; }
FOR_EACH_REG_EXP_TREE_TYPE(MAKE_TYPE_CASE)
#undef MAKE_TYPE_CASE
RegExpEmpty RegExpEmpty::kInstance;
static Interval ListCaptureRegisters(ZoneList<RegExpTree*>* children) {
Interval result = Interval::Empty();
for (int i = 0; i < children->length(); i++)
result = result.Union(children->at(i)->CaptureRegisters());
return result;
}
Interval RegExpAlternative::CaptureRegisters() {
return ListCaptureRegisters(nodes());
}
Interval RegExpDisjunction::CaptureRegisters() {
return ListCaptureRegisters(alternatives());
}
Interval RegExpLookahead::CaptureRegisters() {
return body()->CaptureRegisters();
}
Interval RegExpCapture::CaptureRegisters() {
Interval self(StartRegister(index()), EndRegister(index()));
return self.Union(body()->CaptureRegisters());
}
Interval RegExpQuantifier::CaptureRegisters() {
return body()->CaptureRegisters();
}
bool RegExpAssertion::IsAnchored() {
return type() == RegExpAssertion::START_OF_INPUT;
}
bool RegExpAlternative::IsAnchored() {
ZoneList<RegExpTree*>* nodes = this->nodes();
for (int i = 0; i < nodes->length(); i++) {
RegExpTree* node = nodes->at(i);
if (node->IsAnchored()) { return true; }
if (node->max_match() > 0) { return false; }
}
return false;
}
bool RegExpDisjunction::IsAnchored() {
ZoneList<RegExpTree*>* alternatives = this->alternatives();
for (int i = 0; i < alternatives->length(); i++) {
if (!alternatives->at(i)->IsAnchored())
return false;
}
return true;
}
bool RegExpLookahead::IsAnchored() {
return is_positive() && body()->IsAnchored();
}
bool RegExpCapture::IsAnchored() {
return body()->IsAnchored();
}
// Convert regular expression trees to a simple sexp representation.
// This representation should be different from the input grammar
// in as many cases as possible, to make it more difficult for incorrect
// parses to look as correct ones which is likely if the input and
// output formats are alike.
class RegExpUnparser: public RegExpVisitor {
public:
RegExpUnparser();
void VisitCharacterRange(CharacterRange that);
SmartPointer<const char> ToString() { return stream_.ToCString(); }
#define MAKE_CASE(Name) virtual void* Visit##Name(RegExp##Name*, void* data);
FOR_EACH_REG_EXP_TREE_TYPE(MAKE_CASE)
#undef MAKE_CASE
private:
StringStream* stream() { return &stream_; }
HeapStringAllocator alloc_;
StringStream stream_;
};
RegExpUnparser::RegExpUnparser() : stream_(&alloc_) {
}
void* RegExpUnparser::VisitDisjunction(RegExpDisjunction* that, void* data) {
stream()->Add("(|");
for (int i = 0; i < that->alternatives()->length(); i++) {
stream()->Add(" ");
that->alternatives()->at(i)->Accept(this, data);
}
stream()->Add(")");
return NULL;
}
void* RegExpUnparser::VisitAlternative(RegExpAlternative* that, void* data) {
stream()->Add("(:");
for (int i = 0; i < that->nodes()->length(); i++) {
stream()->Add(" ");
that->nodes()->at(i)->Accept(this, data);
}
stream()->Add(")");
return NULL;
}
void RegExpUnparser::VisitCharacterRange(CharacterRange that) {
stream()->Add("%k", that.from());
if (!that.IsSingleton()) {
stream()->Add("-%k", that.to());
}
}
void* RegExpUnparser::VisitCharacterClass(RegExpCharacterClass* that,
void* data) {
if (that->is_negated())
stream()->Add("^");
stream()->Add("[");
for (int i = 0; i < that->ranges()->length(); i++) {
if (i > 0) stream()->Add(" ");
VisitCharacterRange(that->ranges()->at(i));
}
stream()->Add("]");
return NULL;
}
void* RegExpUnparser::VisitAssertion(RegExpAssertion* that, void* data) {
switch (that->type()) {
case RegExpAssertion::START_OF_INPUT:
stream()->Add("@^i");
break;
case RegExpAssertion::END_OF_INPUT:
stream()->Add("@$i");
break;
case RegExpAssertion::START_OF_LINE:
stream()->Add("@^l");
break;
case RegExpAssertion::END_OF_LINE:
stream()->Add("@$l");
break;
case RegExpAssertion::BOUNDARY:
stream()->Add("@b");
break;
case RegExpAssertion::NON_BOUNDARY:
stream()->Add("@B");
break;
}
return NULL;
}
void* RegExpUnparser::VisitAtom(RegExpAtom* that, void* data) {
stream()->Add("'");
Vector<const uc16> chardata = that->data();
for (int i = 0; i < chardata.length(); i++) {
stream()->Add("%k", chardata[i]);
}
stream()->Add("'");
return NULL;
}
void* RegExpUnparser::VisitText(RegExpText* that, void* data) {
if (that->elements()->length() == 1) {
that->elements()->at(0).data.u_atom->Accept(this, data);
} else {
stream()->Add("(!");
for (int i = 0; i < that->elements()->length(); i++) {
stream()->Add(" ");
that->elements()->at(i).data.u_atom->Accept(this, data);
}
stream()->Add(")");
}
return NULL;
}
void* RegExpUnparser::VisitQuantifier(RegExpQuantifier* that, void* data) {
stream()->Add("(# %i ", that->min());
if (that->max() == RegExpTree::kInfinity) {
stream()->Add("- ");
} else {
stream()->Add("%i ", that->max());
}
stream()->Add(that->is_greedy() ? "g " : that->is_possessive() ? "p " : "n ");
that->body()->Accept(this, data);
stream()->Add(")");
return NULL;
}
void* RegExpUnparser::VisitCapture(RegExpCapture* that, void* data) {
stream()->Add("(^ ");
that->body()->Accept(this, data);
stream()->Add(")");
return NULL;
}
void* RegExpUnparser::VisitLookahead(RegExpLookahead* that, void* data) {
stream()->Add("(-> ");
stream()->Add(that->is_positive() ? "+ " : "- ");
that->body()->Accept(this, data);
stream()->Add(")");
return NULL;
}
void* RegExpUnparser::VisitBackReference(RegExpBackReference* that,
void* data) {
stream()->Add("(<- %i)", that->index());
return NULL;
}
void* RegExpUnparser::VisitEmpty(RegExpEmpty* that, void* data) {
stream()->Put('%');
return NULL;
}
SmartPointer<const char> RegExpTree::ToString() {
RegExpUnparser unparser;
Accept(&unparser, NULL);
return unparser.ToString();
}
RegExpDisjunction::RegExpDisjunction(ZoneList<RegExpTree*>* alternatives)
: alternatives_(alternatives) {
ASSERT(alternatives->length() > 1);
RegExpTree* first_alternative = alternatives->at(0);
min_match_ = first_alternative->min_match();
max_match_ = first_alternative->max_match();
for (int i = 1; i < alternatives->length(); i++) {
RegExpTree* alternative = alternatives->at(i);
min_match_ = Min(min_match_, alternative->min_match());
max_match_ = Max(max_match_, alternative->max_match());
}
}
RegExpAlternative::RegExpAlternative(ZoneList<RegExpTree*>* nodes)
: nodes_(nodes) {
ASSERT(nodes->length() > 1);
min_match_ = 0;
max_match_ = 0;
for (int i = 0; i < nodes->length(); i++) {
RegExpTree* node = nodes->at(i);
min_match_ += node->min_match();
int node_max_match = node->max_match();
if (kInfinity - max_match_ < node_max_match) {
max_match_ = kInfinity;
} else {
max_match_ += node->max_match();
}
}
}
// IsPrimitive implementation. IsPrimitive is true if the value of an
// expression is known at compile-time to be any JS type other than Object
// (e.g, it is Undefined, Null, Boolean, String, or Number).
// The following expression types are never primitive because they express
// Object values.
bool FunctionLiteral::IsPrimitive() { return false; }
bool FunctionBoilerplateLiteral::IsPrimitive() { return false; }
bool RegExpLiteral::IsPrimitive() { return false; }
bool ObjectLiteral::IsPrimitive() { return false; }
bool ArrayLiteral::IsPrimitive() { return false; }
bool CatchExtensionObject::IsPrimitive() { return false; }
bool CallNew::IsPrimitive() { return false; }
bool ThisFunction::IsPrimitive() { return false; }
// The following expression types are not always primitive because we do not
// have enough information to conclude that they are.
bool VariableProxy::IsPrimitive() { return false; }
bool Property::IsPrimitive() { return false; }
bool Call::IsPrimitive() { return false; }
bool CallRuntime::IsPrimitive() { return false; }
// The value of a conditional is the value of one of the alternatives. It's
// always primitive if both alternatives are always primitive.
bool Conditional::IsPrimitive() {
return then_expression()->IsPrimitive() && else_expression()->IsPrimitive();
}
// A literal is primitive when it is not a JSObject.
bool Literal::IsPrimitive() { return !handle()->IsJSObject(); }
// The value of an assignment is the value of its right-hand side.
bool Assignment::IsPrimitive() {
switch (op()) {
case Token::INIT_VAR:
case Token::INIT_CONST:
case Token::ASSIGN:
return value()->IsPrimitive();
default:
// {|=, ^=, &=, <<=, >>=, >>>=, +=, -=, *=, /=, %=}
// Arithmetic operations are always primitive. They express Numbers
// with the exception of +, which expresses a Number or a String.
return true;
}
}
// Throw does not express a value, so it's trivially always primitive.
bool Throw::IsPrimitive() { return true; }
// Unary operations always express primitive values. delete and ! express
// Booleans, void Undefined, typeof String, +, -, and ~ Numbers.
bool UnaryOperation::IsPrimitive() { return true; }
// Count operations (pre- and post-fix increment and decrement) always
// express primitive values (Numbers). See ECMA-262-3, 11.3.1, 11.3.2,
// 11.4.4, ane 11.4.5.
bool CountOperation::IsPrimitive() { return true; }
// Binary operations depend on the operator.
bool BinaryOperation::IsPrimitive() {
switch (op()) {
case Token::COMMA:
// Value is the value of the right subexpression.
return right()->IsPrimitive();
case Token::OR:
case Token::AND:
// Value is the value one of the subexpressions.
return left()->IsPrimitive() && right()->IsPrimitive();
default:
// {|, ^, &, <<, >>, >>>, +, -, *, /, %}
// Arithmetic operations are always primitive. They express Numbers
// with the exception of +, which expresses a Number or a String.
return true;
}
}
// Compare operations always express Boolean values.
bool CompareOperation::IsPrimitive() { return true; }
} } // namespace v8::internal