CopyForwardGMPCardCleaner.hpp

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/**
 * @file
 * @ingroup GC_Modron_Standard
 */

#if !defined(COPYFORWARDGMPCARDCLEANER_HPP_)
#define COPYFORWARDGMPCARDCLEANER_HPP_


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

#include "CardCleaner.hpp"

class MM_CycleState;
class MM_HeapMap;
class MM_CopyForwardScheme;

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

class MM_CopyForwardGMPCardCleaner : public MM_CardCleaner
{
	/* Data Members */
private:
	MM_CopyForwardScheme *const _copyForwardScheme;  /**< The 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_COPY_FORWARD_GMP_CARD_CLEANER; }

public:	
	
	/**
	 * Create a CardCleaner object for updating RSM and next mark map.
	 */
	MM_CopyForwardGMPCardCleaner(MM_CopyForwardScheme *copyForwardScheme);
};

#endif /* COPYFORWARDGMPCARDCLEANER_HPP_ */