IncrementalOverflow.hpp

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 * the terms of the Eclipse Public License 2.0 which accompanies this
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/**
 * @file
 * @ingroup GC_Modron_Standard
 */

#if !defined(INCREMENTALOVERFLOW_HPP_)
#define INCREMENTALOVERFLOW_HPP_

#include "EnvironmentBase.hpp"
#include "Metronome.hpp"
#include "WorkPacketOverflow.hpp"

class MM_Packet;
class MM_HeapRegionDescriptorRealtime;

/**
 * @todo Provide class documentation
 */
class MM_IncrementalOverflow : public MM_WorkPacketOverflow
{
/* Data members & types */
public:
protected:
private:
	MM_GCExtensionsBase *_extensions;
	MM_HeapRegionDescriptorRealtime *_overflowList;
	bool _overflowThisGCCycle; /**< set to signify an overflow happened sometime during GC cycle */
	
/* Methods */
public:
	static MM_IncrementalOverflow *newInstance(MM_EnvironmentBase *env, MM_WorkPackets *workPackets);
	virtual void reset(MM_EnvironmentBase *env);
	
	virtual bool isEmpty()
	{
		return (_overflowList == NULL);
	}
	
	bool isOverflowThisGCCycle() const { return _overflowThisGCCycle; }
	void resetOverflowThisGCCycle() { _overflowThisGCCycle = false; }
	
	virtual void emptyToOverflow(MM_EnvironmentBase *env, MM_Packet *packet, MM_OverflowType type);
	virtual void fillFromOverflow(MM_EnvironmentBase *env, MM_Packet *packet);
	virtual void overflowItem(MM_EnvironmentBase *env, void *item, MM_OverflowType type);

	/**
	 * Create a IncrementalOverflow object.
	 */	
	MM_IncrementalOverflow(MM_EnvironmentBase *env, MM_WorkPackets *workPackets) :
		MM_WorkPacketOverflow(env, workPackets),
		_overflowList(NULL),
		_overflowThisGCCycle(false)
	{
		_typeId = __FUNCTION__;
	};
	
protected:
	bool initialize(MM_EnvironmentBase *env);
	void tearDown(MM_EnvironmentBase *env);
private:
	void overflowItemInternal(MM_EnvironmentBase *env, void *item, MM_OverflowType type);
	void push(MM_EnvironmentBase *env, MM_HeapRegionDescriptorRealtime *region);
	void pushNoLock(MM_EnvironmentBase *env, MM_HeapRegionDescriptorRealtime *region);
	MM_HeapRegionDescriptorRealtime *pop(MM_EnvironmentBase *env);
	void pushLocal(MM_EnvironmentBase *env, MM_HeapRegionDescriptorRealtime *region, MM_OverflowType type);
	void flushLocal(MM_EnvironmentBase *env, MM_OverflowType type);
};

#endif /* INCREMENTALOVERFLOW_HPP_ */