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/*
* Copyright (C) 2012, 2014, 2015 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. Neither the name of Apple Inc. ("Apple") 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 APPLE AND ITS 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 APPLE OR ITS 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.
*/
#ifndef JSSymbolTableObject_h
#define JSSymbolTableObject_h
#include "JSScope.h"
#include "PropertyDescriptor.h"
#include "SymbolTable.h"
#include "VariableWriteFireDetail.h"
namespace JSC {
class JSSymbolTableObject;
class JSSymbolTableObject : public JSScope {
public:
typedef JSScope Base;
static const unsigned StructureFlags = Base::StructureFlags | IsEnvironmentRecord | OverridesGetPropertyNames;
SymbolTable* symbolTable() const { return m_symbolTable.get(); }
JS_EXPORT_PRIVATE static bool deleteProperty(JSCell*, ExecState*, PropertyName);
JS_EXPORT_PRIVATE static void getOwnNonIndexPropertyNames(JSObject*, ExecState*, PropertyNameArray&, EnumerationMode);
static ptrdiff_t offsetOfSymbolTable() { return OBJECT_OFFSETOF(JSSymbolTableObject, m_symbolTable); }
protected:
JSSymbolTableObject(VM& vm, Structure* structure, JSScope* scope)
: Base(vm, structure, scope)
{
}
JSSymbolTableObject(VM& vm, Structure* structure, JSScope* scope, SymbolTable* symbolTable)
: Base(vm, structure, scope)
{
ASSERT(symbolTable);
setSymbolTable(vm, symbolTable);
}
void setSymbolTable(VM& vm, SymbolTable* symbolTable)
{
ASSERT(!m_symbolTable);
symbolTable->singletonScope()->notifyWrite(vm, this, "Allocated a scope");
m_symbolTable.set(vm, this, symbolTable);
}
static void visitChildren(JSCell*, SlotVisitor&);
private:
WriteBarrier<SymbolTable> m_symbolTable;
};
template<typename SymbolTableObjectType>
inline bool symbolTableGet(
SymbolTableObjectType* object, PropertyName propertyName, PropertySlot& slot)
{
SymbolTable& symbolTable = *object->symbolTable();
ConcurrentJITLocker locker(symbolTable.m_lock);
SymbolTable::Map::iterator iter = symbolTable.find(locker, propertyName.uid());
if (iter == symbolTable.end(locker))
return false;
SymbolTableEntry::Fast entry = iter->value;
ASSERT(!entry.isNull());
ScopeOffset offset = entry.scopeOffset();
// Defend against the inspector asking for a var after it has been optimized out.
if (!object->isValidScopeOffset(offset))
return false;
slot.setValue(object, entry.getAttributes() | DontDelete, object->variableAt(offset).get());
return true;
}
template<typename SymbolTableObjectType>
inline bool symbolTableGet(
SymbolTableObjectType* object, PropertyName propertyName, PropertyDescriptor& descriptor)
{
SymbolTable& symbolTable = *object->symbolTable();
ConcurrentJITLocker locker(symbolTable.m_lock);
SymbolTable::Map::iterator iter = symbolTable.find(locker, propertyName.uid());
if (iter == symbolTable.end(locker))
return false;
SymbolTableEntry::Fast entry = iter->value;
ASSERT(!entry.isNull());
ScopeOffset offset = entry.scopeOffset();
// Defend against the inspector asking for a var after it has been optimized out.
if (!object->isValidScopeOffset(offset))
return false;
descriptor.setDescriptor(object->variableAt(offset).get(), entry.getAttributes() | DontDelete);
return true;
}
template<typename SymbolTableObjectType>
inline bool symbolTableGet(
SymbolTableObjectType* object, PropertyName propertyName, PropertySlot& slot,
bool& slotIsWriteable)
{
SymbolTable& symbolTable = *object->symbolTable();
ConcurrentJITLocker locker(symbolTable.m_lock);
SymbolTable::Map::iterator iter = symbolTable.find(locker, propertyName.uid());
if (iter == symbolTable.end(locker))
return false;
SymbolTableEntry::Fast entry = iter->value;
ASSERT(!entry.isNull());
ScopeOffset offset = entry.scopeOffset();
// Defend against the inspector asking for a var after it has been optimized out.
if (!object->isValidScopeOffset(offset))
return false;
slot.setValue(object, entry.getAttributes() | DontDelete, object->variableAt(offset).get());
slotIsWriteable = !entry.isReadOnly();
return true;
}
enum class SymbolTablePutMode {
WithAttributes,
WithoutAttributes
};
template<SymbolTablePutMode symbolTablePutMode, typename SymbolTableObjectType>
inline bool symbolTablePut(
SymbolTableObjectType* object, ExecState* exec, PropertyName propertyName, JSValue value, unsigned attributes,
bool shouldThrowReadOnlyError, bool ignoreReadOnlyErrors, WatchpointSet*& set)
{
ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(object));
VM& vm = exec->vm();
WriteBarrierBase<Unknown>* reg;
{
SymbolTable& symbolTable = *object->symbolTable();
// FIXME: This is very suspicious. We shouldn't need a GC-safe lock here.
// https://bugs.webkit.org/show_bug.cgi?id=134601
GCSafeConcurrentJITLocker locker(symbolTable.m_lock, vm.heap);
SymbolTable::Map::iterator iter = symbolTable.find(locker, propertyName.uid());
if (iter == symbolTable.end(locker))
return false;
bool wasFat;
SymbolTableEntry::Fast fastEntry = iter->value.getFast(wasFat);
ASSERT(!fastEntry.isNull());
if (fastEntry.isReadOnly() && !ignoreReadOnlyErrors) {
if (shouldThrowReadOnlyError)
throwTypeError(exec, StrictModeReadonlyPropertyWriteError);
return true;
}
ScopeOffset offset = fastEntry.scopeOffset();
// Defend against the inspector asking for a var after it has been optimized out.
if (!object->isValidScopeOffset(offset))
return false;
set = iter->value.watchpointSet();
if (symbolTablePutMode == SymbolTablePutMode::WithAttributes)
iter->value.setAttributes(attributes);
reg = &object->variableAt(offset);
}
// I'd prefer we not hold lock while executing barriers, since I prefer to reserve
// the right for barriers to be able to trigger GC. And I don't want to hold VM
// locks while GC'ing.
reg->set(vm, object, value);
return true;
}
template<typename SymbolTableObjectType>
inline bool symbolTablePutTouchWatchpointSet(
SymbolTableObjectType* object, ExecState* exec, PropertyName propertyName, JSValue value,
bool shouldThrowReadOnlyError, bool ignoreReadOnlyErrors)
{
WatchpointSet* set = nullptr;
unsigned attributes = 0;
bool result = symbolTablePut<SymbolTablePutMode::WithoutAttributes>(object, exec, propertyName, value, attributes, shouldThrowReadOnlyError, ignoreReadOnlyErrors, set);
if (set)
VariableWriteFireDetail::touch(set, object, propertyName);
return result;
}
template<typename SymbolTableObjectType>
inline bool symbolTablePutInvalidateWatchpointSet(
SymbolTableObjectType* object, ExecState* exec, PropertyName propertyName, JSValue value,
bool shouldThrowReadOnlyError, bool ignoreReadOnlyErrors)
{
WatchpointSet* set = nullptr;
unsigned attributes = 0;
bool result = symbolTablePut<SymbolTablePutMode::WithoutAttributes>(object, exec, propertyName, value, attributes, shouldThrowReadOnlyError, ignoreReadOnlyErrors, set);
if (set)
set->invalidate(VariableWriteFireDetail(object, propertyName)); // Don't mess around - if we had found this statically, we would have invalidated it.
return result;
}
template<typename SymbolTableObjectType>
inline bool symbolTablePutWithAttributesTouchWatchpointSet(
SymbolTableObjectType* object, ExecState* exec, PropertyName propertyName,
JSValue value, unsigned attributes)
{
WatchpointSet* set = nullptr;
bool shouldThrowReadOnlyError = false;
bool ignoreReadOnlyErrors = true;
bool result = symbolTablePut<SymbolTablePutMode::WithAttributes>(object, exec, propertyName, value, attributes, shouldThrowReadOnlyError, ignoreReadOnlyErrors, set);
if (set)
VariableWriteFireDetail::touch(set, object, propertyName);
return result;
}
} // namespace JSC
#endif // JSSymbolTableObject_h
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