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/*
* Copyright (C) 2011, 2012 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. 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 INC. 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 SlotVisitor_h
#define SlotVisitor_h
#include "HandleTypes.h"
#include "MarkStackInlines.h"
#include <wtf/text/StringHash.h>
namespace JSC {
class ConservativeRoots;
class GCThreadSharedData;
class Heap;
template<typename T> class Weak;
template<typename T> class WriteBarrierBase;
template<typename T> class JITWriteBarrier;
class SlotVisitor {
WTF_MAKE_NONCOPYABLE(SlotVisitor);
friend class HeapRootVisitor; // Allowed to mark a JSValue* or JSCell** directly.
public:
SlotVisitor(GCThreadSharedData&);
~SlotVisitor();
void append(ConservativeRoots&);
template<typename T> void append(JITWriteBarrier<T>*);
template<typename T> void append(WriteBarrierBase<T>*);
void appendValues(WriteBarrierBase<Unknown>*, size_t count);
template<typename T>
void appendUnbarrieredPointer(T**);
void appendUnbarrieredValue(JSValue*);
template<typename T>
void appendUnbarrieredWeak(Weak<T>*);
void addOpaqueRoot(void*);
bool containsOpaqueRoot(void*);
TriState containsOpaqueRootTriState(void*);
int opaqueRootCount();
GCThreadSharedData& sharedData() { return m_shared; }
bool isEmpty() { return m_stack.isEmpty(); }
void setup();
void reset();
size_t visitCount() const { return m_visitCount; }
void donate();
void drain();
void donateAndDrain();
enum SharedDrainMode { SlaveDrain, MasterDrain };
void drainFromShared(SharedDrainMode);
void harvestWeakReferences();
void finalizeUnconditionalFinalizers();
void copyLater(JSCell*, void*, size_t);
#if ENABLE(SIMPLE_HEAP_PROFILING)
VTableSpectrum m_visitedTypeCounts;
#endif
void addWeakReferenceHarvester(WeakReferenceHarvester*);
void addUnconditionalFinalizer(UnconditionalFinalizer*);
#if ENABLE(OBJECT_MARK_LOGGING)
inline void resetChildCount() { m_logChildCount = 0; }
inline unsigned childCount() { return m_logChildCount; }
inline void incrementChildCount() { m_logChildCount++; }
#endif
private:
friend class ParallelModeEnabler;
JS_EXPORT_PRIVATE static void validate(JSCell*);
void append(JSValue*);
void append(JSValue*, size_t count);
void append(JSCell**);
void internalAppend(JSCell*);
void internalAppend(JSValue);
void internalAppend(JSValue*);
JS_EXPORT_PRIVATE void mergeOpaqueRoots();
void mergeOpaqueRootsIfNecessary();
void mergeOpaqueRootsIfProfitable();
void donateKnownParallel();
MarkStackArray m_stack;
HashSet<void*> m_opaqueRoots; // Handle-owning data structures not visible to the garbage collector.
size_t m_visitCount;
bool m_isInParallelMode;
GCThreadSharedData& m_shared;
bool m_shouldHashCons; // Local per-thread copy of shared flag for performance reasons
typedef HashMap<StringImpl*, JSValue> UniqueStringMap;
UniqueStringMap m_uniqueStrings;
#if ENABLE(OBJECT_MARK_LOGGING)
unsigned m_logChildCount;
#endif
public:
#if !ASSERT_DISABLED
bool m_isCheckingForDefaultMarkViolation;
bool m_isDraining;
#endif
};
class ParallelModeEnabler {
public:
ParallelModeEnabler(SlotVisitor& stack)
: m_stack(stack)
{
ASSERT(!m_stack.m_isInParallelMode);
m_stack.m_isInParallelMode = true;
}
~ParallelModeEnabler()
{
ASSERT(m_stack.m_isInParallelMode);
m_stack.m_isInParallelMode = false;
}
private:
SlotVisitor& m_stack;
};
} // namespace JSC
#endif // SlotVisitor_h
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