GlobalCollectionCardCleaner.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(GLOBALCOLLECTIONCARDCLEANER_HPP_)
#define GLOBALCOLLECTIONCARDCLEANER_HPP_


#include "j9.h"
#include "j9cfg.h"
#include "j9modron.h"

#include "CardCleaner.hpp"

class MM_GlobalMarkingScheme;
class MM_HeapMap;

/**
 * @todo Provide typedef documentation
 * @ingroup GC_Modron_Standard
 */

class MM_GlobalCollectionCardCleaner : public MM_CardCleaner 
{
	/* Data Members */
private:
	MM_GlobalMarkingScheme * const _markingScheme;	/**< The marking scheme to use for scanning objects which have been modified since they were last scanned */
protected:
public:

	/* Member Functions */
private:
protected:
	/**
	 * Clean a range of addresses (typically within a span of a card).
	 * This class is used for updating the RSM based on the previous mark map and scanning modified objects in the next mark map
	 * (note that next is always a subset of previous so anything not marked in next but marked in previous only requires RSM
	 * inter-region reference updating while objects marked in both require RSM updates and object scanning to update the next
	 * mark map).
	 *
	 * @param[in] env A thread (typically the thread initializing the GC)
	 * @param[in] lowAddress low address of the range to be cleaned
	 * @param[in] highAddress high address of the range to be cleaned 
	 * @param cardToClean[in/out] The card which we are cleaning
	 */		
	virtual void clean(MM_EnvironmentBase *env, void *lowAddress, void *highAddress, Card *cardToClean);

	/**
	 * @see MM_CardCleaner::getVMStateID()
	 */
	virtual UDATA getVMStateID() { return OMRVMSTATE_GC_GLOBAL_COLLECTION_CARD_CLEANER; }

public:	
	
	/**
	 * Create a CardCleaner object for updating RSM and next mark map.
	 */
	MM_GlobalCollectionCardCleaner(MM_GlobalMarkingScheme *markingScheme)
		: MM_CardCleaner()
		, _markingScheme(markingScheme)
	{
		_typeId = __FUNCTION__;
	}
};

#endif /* GLOBALCOLLECTIONCARDCLEANER_HPP_ */