#pragma once
#include "GenericArguments.h"
#include "JSLexicalEnvironment.h"
namespace JSC {
class ScopedArguments final : public GenericArguments<ScopedArguments> {
private:
ScopedArguments(VM&, Structure*, WriteBarrier<Unknown>* storage, unsigned totalLength);
void finishCreation(VM&, JSFunction* callee, ScopedArgumentsTable*, JSLexicalEnvironment*);
using Base = GenericArguments<ScopedArguments>;
public:
template<typename CellType, SubspaceAccess>
static IsoSubspace* subspaceFor(VM& vm)
{
static_assert(!CellType::needsDestruction, "");
return &vm.scopedArgumentsSpace;
}
static ScopedArguments* createUninitialized(VM&, Structure*, JSFunction* callee, ScopedArgumentsTable*, JSLexicalEnvironment*, unsigned totalLength);
static ScopedArguments* create(VM&, Structure*, JSFunction* callee, ScopedArgumentsTable*, JSLexicalEnvironment*, unsigned totalLength);
static ScopedArguments* createByCopying(JSGlobalObject*, CallFrame*, ScopedArgumentsTable*, JSLexicalEnvironment*);
static ScopedArguments* createByCopyingFrom(VM&, Structure*, Register* argumentsStart, unsigned totalLength, JSFunction* callee, ScopedArgumentsTable*, JSLexicalEnvironment*);
static void visitChildren(JSCell*, SlotVisitor&);
uint32_t internalLength() const
{
return m_totalLength;
}
uint32_t length(JSGlobalObject* globalObject) const
{
VM& vm = getVM(globalObject);
auto scope = DECLARE_THROW_SCOPE(vm);
if (UNLIKELY(m_overrodeThings)) {
auto value = get(globalObject, vm.propertyNames->length);
RETURN_IF_EXCEPTION(scope, 0);
RELEASE_AND_RETURN(scope, value.toUInt32(globalObject));
}
return internalLength();
}
bool isMappedArgument(uint32_t i) const
{
if (i >= m_totalLength)
return false;
unsigned namedLength = m_table->length();
if (i < namedLength)
return !!m_table->get(i);
return !!storage()[i - namedLength].get();
}
bool isMappedArgumentInDFG(uint32_t i) const
{
return isMappedArgument(i);
}
JSValue getIndexQuickly(uint32_t i) const
{
ASSERT_WITH_SECURITY_IMPLICATION(isMappedArgument(i));
unsigned namedLength = m_table->length();
if (i < namedLength)
return m_scope->variableAt(m_table->get(i)).get();
return storage()[i - namedLength].get();
}
void setIndexQuickly(VM& vm, uint32_t i, JSValue value)
{
ASSERT_WITH_SECURITY_IMPLICATION(isMappedArgument(i));
unsigned namedLength = m_table->length();
if (i < namedLength)
m_scope->variableAt(m_table->get(i)).set(vm, m_scope.get(), value);
else
storage()[i - namedLength].set(vm, this, value);
}
JSFunction* callee()
{
return m_callee.get();
}
bool overrodeThings() const { return m_overrodeThings; }
void overrideThings(JSGlobalObject*);
void overrideThingsIfNecessary(JSGlobalObject*);
void unmapArgument(JSGlobalObject*, uint32_t index);
void initModifiedArgumentsDescriptorIfNecessary(JSGlobalObject* globalObject)
{
GenericArguments<ScopedArguments>::initModifiedArgumentsDescriptorIfNecessary(globalObject, m_table->length());
}
void setModifiedArgumentDescriptor(JSGlobalObject* globalObject, unsigned index)
{
GenericArguments<ScopedArguments>::setModifiedArgumentDescriptor(globalObject, index, m_table->length());
}
bool isModifiedArgumentDescriptor(unsigned index)
{
return GenericArguments<ScopedArguments>::isModifiedArgumentDescriptor(index, m_table->length());
}
void copyToArguments(JSGlobalObject*, JSValue* firstElementDest, unsigned offset, unsigned length);
DECLARE_INFO;
static Structure* createStructure(VM&, JSGlobalObject*, JSValue prototype);
static ptrdiff_t offsetOfOverrodeThings() { return OBJECT_OFFSETOF(ScopedArguments, m_overrodeThings); }
static ptrdiff_t offsetOfTotalLength() { return OBJECT_OFFSETOF(ScopedArguments, m_totalLength); }
static ptrdiff_t offsetOfTable() { return OBJECT_OFFSETOF(ScopedArguments, m_table); }
static ptrdiff_t offsetOfScope() { return OBJECT_OFFSETOF(ScopedArguments, m_scope); }
static ptrdiff_t offsetOfStorage() { return OBJECT_OFFSETOF(ScopedArguments, m_storage); }
private:
WriteBarrier<Unknown>* storage() const
{
return m_storage.get();
}
bool m_overrodeThings { false }; unsigned m_totalLength; WriteBarrier<JSFunction> m_callee;
WriteBarrier<ScopedArgumentsTable> m_table;
WriteBarrier<JSLexicalEnvironment> m_scope;
AuxiliaryBarrier<WriteBarrier<Unknown>*> m_storage;
};
}