void JSLexicalEnvironment::visitChildren(JSCell* cell, SlotVisitor& visitor)
{
JSLexicalEnvironment* thisObject = jsCast<JSLexicalEnvironment*>(cell);
ASSERT_GC_OBJECT_INHERITS(thisObject, info());
Base::visitChildren(thisObject, visitor);
for (int i = 0; i < thisObject->symbolTable()->captureCount(); ++i)
visitor.append(&thisObject->storage()[i]);
}
JSValue DebuggerScope::caughtValue(ExecState* exec) const
{
ASSERT(isCatchScope());
JSLexicalEnvironment* catchEnvironment = jsCast<JSLexicalEnvironment*>(m_scope.get());
SymbolTable* catchSymbolTable = catchEnvironment->symbolTable();
RELEASE_ASSERT(catchSymbolTable->size() == 1);
PropertyName errorName(catchSymbolTable->begin(catchSymbolTable->m_lock)->key.get());
PropertySlot slot(m_scope.get());
bool success = catchEnvironment->getOwnPropertySlot(catchEnvironment, exec, errorName, slot);
RELEASE_ASSERT(success && slot.isValue());
return slot.getValue(exec, errorName);
}
void JSLexicalEnvironment::put(JSCell* cell, ExecState* exec, PropertyName propertyName, JSValue value, PutPropertySlot& slot)
{
JSLexicalEnvironment* thisObject = jsCast<JSLexicalEnvironment*>(cell);
ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(thisObject));
if (thisObject->symbolTablePut(exec, propertyName, value, slot.isStrictMode()))
return;
// We don't call through to JSObject because __proto__ and getter/setter
// properties are non-standard extensions that other implementations do not
// expose in the lexicalEnvironment object.
ASSERT(!thisObject->hasGetterSetterProperties());
thisObject->putOwnDataProperty(exec->vm(), propertyName, value, slot);
}
bool JSLexicalEnvironment::put(JSCell* cell, ExecState* exec, PropertyName propertyName, JSValue value, PutPropertySlot& slot)
{
JSLexicalEnvironment* thisObject = jsCast<JSLexicalEnvironment*>(cell);
ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(thisObject));
bool shouldThrowReadOnlyError = slot.isStrictMode() || thisObject->isLexicalScope();
bool ignoreReadOnlyErrors = false;
bool putResult = false;
if (symbolTablePutInvalidateWatchpointSet(thisObject, exec, propertyName, value, shouldThrowReadOnlyError, ignoreReadOnlyErrors, putResult))
return putResult;
// We don't call through to JSObject because __proto__ and getter/setter
// properties are non-standard extensions that other implementations do not
// expose in the lexicalEnvironment object.
ASSERT(!thisObject->hasGetterSetterProperties());
return thisObject->putOwnDataProperty(exec->vm(), propertyName, value, slot);
}
void JSLexicalEnvironment::getOwnNonIndexPropertyNames(JSObject* object, ExecState* exec, PropertyNameArray& propertyNames, EnumerationMode mode)
{
JSLexicalEnvironment* thisObject = jsCast<JSLexicalEnvironment*>(object);
{
ConcurrentJITLocker locker(thisObject->symbolTable()->m_lock);
SymbolTable::Map::iterator end = thisObject->symbolTable()->end(locker);
for (SymbolTable::Map::iterator it = thisObject->symbolTable()->begin(locker); it != end; ++it) {
if (it->value.getAttributes() & DontEnum && !shouldIncludeDontEnumProperties(mode))
continue;
if (!thisObject->isValid(it->value))
continue;
propertyNames.add(Identifier(exec, it->key.get()));
}
}
// Skip the JSEnvironmentRecord implementation of getOwnNonIndexPropertyNames
JSObject::getOwnNonIndexPropertyNames(thisObject, exec, propertyNames, mode);
}
bool JSLexicalEnvironment::getOwnPropertySlot(JSObject* object, ExecState* exec, PropertyName propertyName, PropertySlot& slot)
{
JSLexicalEnvironment* thisObject = jsCast<JSLexicalEnvironment*>(object);
if (thisObject->symbolTableGet(propertyName, slot))
return true;
unsigned attributes;
if (JSValue value = thisObject->getDirect(exec->vm(), propertyName, attributes)) {
slot.setValue(thisObject, attributes, value);
return true;
}
// We don't call through to JSObject because there's no way to give a
// lexical environment object getter properties or a prototype.
ASSERT(!thisObject->hasGetterSetterProperties());
ASSERT(thisObject->prototype().isNull());
return false;
}
// Returns true if we found enough information to terminate optimization.
static inline bool abstractAccess(ExecState* exec, JSScope* scope, const Identifier& ident, GetOrPut getOrPut, size_t depth, bool& needsVarInjectionChecks, ResolveOp& op, InitializationMode initializationMode)
{
if (scope->isJSLexicalEnvironment()) {
JSLexicalEnvironment* lexicalEnvironment = jsCast<JSLexicalEnvironment*>(scope);
if (ident == exec->propertyNames().arguments) {
// We know the property will be at this lexical environment scope, but we don't know how to cache it.
op = ResolveOp(Dynamic, 0, 0, 0, 0, 0);
return true;
}
SymbolTable* symbolTable = lexicalEnvironment->symbolTable();
{
ConcurrentJSLocker locker(symbolTable->m_lock);
auto iter = symbolTable->find(locker, ident.impl());
if (iter != symbolTable->end(locker)) {
SymbolTableEntry& entry = iter->value;
ASSERT(!entry.isNull());
if (entry.isReadOnly() && getOrPut == Put) {
// We know the property will be at this lexical environment scope, but we don't know how to cache it.
op = ResolveOp(Dynamic, 0, 0, 0, 0, 0);
return true;
}
op = ResolveOp(makeType(ClosureVar, needsVarInjectionChecks), depth, 0, lexicalEnvironment, entry.watchpointSet(), entry.scopeOffset().offset());
return true;
}
}
if (scope->type() == ModuleEnvironmentType) {
JSModuleEnvironment* moduleEnvironment = jsCast<JSModuleEnvironment*>(scope);
AbstractModuleRecord* moduleRecord = moduleEnvironment->moduleRecord();
AbstractModuleRecord::Resolution resolution = moduleRecord->resolveImport(exec, ident);
if (resolution.type == AbstractModuleRecord::Resolution::Type::Resolved) {
AbstractModuleRecord* importedRecord = resolution.moduleRecord;
JSModuleEnvironment* importedEnvironment = importedRecord->moduleEnvironment();
SymbolTable* symbolTable = importedEnvironment->symbolTable();
ConcurrentJSLocker locker(symbolTable->m_lock);
auto iter = symbolTable->find(locker, resolution.localName.impl());
ASSERT(iter != symbolTable->end(locker));
SymbolTableEntry& entry = iter->value;
ASSERT(!entry.isNull());
op = ResolveOp(makeType(ModuleVar, needsVarInjectionChecks), depth, 0, importedEnvironment, entry.watchpointSet(), entry.scopeOffset().offset(), resolution.localName.impl());
return true;
}
}
if (symbolTable->usesNonStrictEval())
needsVarInjectionChecks = true;
return false;
}
if (scope->isGlobalLexicalEnvironment()) {
JSGlobalLexicalEnvironment* globalLexicalEnvironment = jsCast<JSGlobalLexicalEnvironment*>(scope);
SymbolTable* symbolTable = globalLexicalEnvironment->symbolTable();
ConcurrentJSLocker locker(symbolTable->m_lock);
auto iter = symbolTable->find(locker, ident.impl());
if (iter != symbolTable->end(locker)) {
SymbolTableEntry& entry = iter->value;
ASSERT(!entry.isNull());
if (getOrPut == Put && entry.isReadOnly() && !isInitialization(initializationMode)) {
// We know the property will be at global lexical environment, but we don't know how to cache it.
op = ResolveOp(Dynamic, 0, 0, 0, 0, 0);
return true;
}
// We can force const Initialization to always go down the fast path. It is provably impossible to construct
// a program that needs a var injection check here. You can convince yourself of this as follows:
// Any other let/const/class would be a duplicate of this in the global scope, so we would never get here in that situation.
// Also, if we had an eval in the global scope that defined a const, it would also be a duplicate of this const, and so it would
// also throw an error. Therefore, we're *the only* thing that can assign to this "const" slot for the first (and only) time. Also,
// we will never have a Dynamic ResolveType here because if we were inside a "with" statement, that would mean the "const" definition
// isn't a global, it would be a local to the "with" block.
// We still need to make the slow path correct for when we need to fire a watchpoint.
ResolveType resolveType = initializationMode == InitializationMode::ConstInitialization ? GlobalLexicalVar : makeType(GlobalLexicalVar, needsVarInjectionChecks);
op = ResolveOp(
resolveType, depth, 0, 0, entry.watchpointSet(),
reinterpret_cast<uintptr_t>(globalLexicalEnvironment->variableAt(entry.scopeOffset()).slot()));
return true;
}
return false;
}
if (scope->isGlobalObject()) {
JSGlobalObject* globalObject = jsCast<JSGlobalObject*>(scope);
{
SymbolTable* symbolTable = globalObject->symbolTable();
ConcurrentJSLocker locker(symbolTable->m_lock);
auto iter = symbolTable->find(locker, ident.impl());
if (iter != symbolTable->end(locker)) {
SymbolTableEntry& entry = iter->value;
ASSERT(!entry.isNull());
if (getOrPut == Put && entry.isReadOnly()) {
// We know the property will be at global scope, but we don't know how to cache it.
op = ResolveOp(Dynamic, 0, 0, 0, 0, 0);
return true;
}
op = ResolveOp(
makeType(GlobalVar, needsVarInjectionChecks), depth, 0, 0, entry.watchpointSet(),
reinterpret_cast<uintptr_t>(globalObject->variableAt(entry.scopeOffset()).slot()));
return true;
}
}
PropertySlot slot(globalObject, PropertySlot::InternalMethodType::VMInquiry);
bool hasOwnProperty = globalObject->getOwnPropertySlot(globalObject, exec, ident, slot);
if (!hasOwnProperty) {
op = ResolveOp(makeType(UnresolvedProperty, needsVarInjectionChecks), 0, 0, 0, 0, 0);
return true;
}
if (!slot.isCacheableValue()
|| !globalObject->structure()->propertyAccessesAreCacheable()
|| (globalObject->structure()->hasReadOnlyOrGetterSetterPropertiesExcludingProto() && getOrPut == Put)) {
// We know the property will be at global scope, but we don't know how to cache it.
ASSERT(!scope->next());
op = ResolveOp(makeType(GlobalProperty, needsVarInjectionChecks), 0, 0, 0, 0, 0);
return true;
}
WatchpointState state = globalObject->structure()->ensurePropertyReplacementWatchpointSet(exec->vm(), slot.cachedOffset())->state();
if (state == IsWatched && getOrPut == Put) {
// The field exists, but because the replacement watchpoint is still intact. This is
// kind of dangerous. We have two options:
// 1) Invalidate the watchpoint set. That would work, but it's possible that this code
// path never executes - in which case this would be unwise.
// 2) Have the invalidation happen at run-time. All we have to do is leave the code
// uncached. The only downside is slightly more work when this does execute.
// We go with option (2) here because it seems less evil.
op = ResolveOp(makeType(GlobalProperty, needsVarInjectionChecks), depth, 0, 0, 0, 0);
} else
op = ResolveOp(makeType(GlobalProperty, needsVarInjectionChecks), depth, globalObject->structure(), 0, 0, slot.cachedOffset());
return true;
}
op = ResolveOp(Dynamic, 0, 0, 0, 0, 0);
return true;
}
