darling-JavaScriptCore/runtime/ObjectInitializationScope.cpp

119 lines
4.0 KiB
C++

/*
* Copyright (C) 2017-2020 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.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 INC. 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 "config.h"
#include "ObjectInitializationScope.h"
#include "HeapInlines.h"
#include "JSCJSValueInlines.h"
#include "JSCellInlines.h"
#include "JSObject.h"
#include "Scribble.h"
namespace JSC {
#if ASSERT_ENABLED
ObjectInitializationScope::ObjectInitializationScope(VM& vm)
: m_vm(vm)
{
}
ObjectInitializationScope::~ObjectInitializationScope()
{
m_vm.heap.mutatorFence();
if (!m_object)
return;
verifyPropertiesAreInitialized(m_object);
}
void ObjectInitializationScope::notifyAllocated(JSObject* object)
{
ASSERT(!m_disallowGC);
ASSERT(!m_disallowVMEntry);
m_disallowGC.emplace();
m_disallowVMEntry.emplace(m_vm);
m_object = object;
}
void ObjectInitializationScope::notifyInitialized(JSObject* object)
{
if (m_object) {
m_disallowGC.reset();
m_disallowVMEntry.reset();
m_object = nullptr;
}
verifyPropertiesAreInitialized(object);
}
void ObjectInitializationScope::verifyPropertiesAreInitialized(JSObject* object)
{
Butterfly* butterfly = object->butterfly();
Structure* structure = object->structure(m_vm);
IndexingType indexingType = structure->indexingType();
unsigned vectorLength = butterfly->vectorLength();
if (UNLIKELY(hasUndecided(indexingType)) || !hasIndexedProperties(indexingType)) {
// Nothing to verify.
} else if (LIKELY(!hasAnyArrayStorage(indexingType))) {
auto data = butterfly->contiguous().data();
for (unsigned i = 0; i < vectorLength; ++i) {
if (isScribbledValue(data[i].get())) {
dataLogLn("Found scribbled value at i = ", i);
ASSERT_NOT_REACHED();
}
}
} else {
ArrayStorage* storage = butterfly->arrayStorage();
for (unsigned i = 0; i < vectorLength; ++i) {
if (isScribbledValue(storage->m_vector[i].get())) {
dataLogLn("Found scribbled value at i = ", i);
ASSERT_NOT_REACHED();
}
}
}
auto isSafeEmptyValueForGCScanning = [] (JSValue value) {
#if USE(JSVALUE64)
return !value;
#else
return !value || !JSValue::encode(value);
#endif
};
for (int64_t i = 0; i < static_cast<int64_t>(structure->outOfLineCapacity()); i++) {
// We rely on properties past the last offset be zero for concurrent GC.
if (i + firstOutOfLineOffset > structure->maxOffset())
ASSERT(isSafeEmptyValueForGCScanning(butterfly->propertyStorage()[-i - 1].get()));
else if (isScribbledValue(butterfly->propertyStorage()[-i - 1].get())) {
dataLogLn("Found scribbled property at i = ", -i - 1);
ASSERT_NOT_REACHED();
}
}
}
#endif // ASSERT_ENABLED
} // namespace JSC