ConstantPoolClassSlotIterator.cpp

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 * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
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/**
 * @file
 * @ingroup GC_Structs
 */

#include "j9.h"
#include "j9cfg.h"
#include "j9cp.h"

#include "ConstantPoolClassSlotIterator.hpp"

/**
 * @return the next Class reference from the constant pool
 * @return NULL if there are no more references
 */
J9Class *
GC_ConstantPoolClassSlotIterator::nextSlot()
{
	J9Class *classPtr = NULL;
	while (_cpEntryCount) {
		if (0 == _cpDescriptionIndex) {
			_cpDescription = *_cpDescriptionSlots;
			_cpDescriptionSlots += 1;
			_cpDescriptionIndex = J9_CP_DESCRIPTIONS_PER_U32;
		}

		U_32 slotType = _cpDescription & J9_CP_DESCRIPTION_MASK;
		J9Object **slotPtr = _cpEntry;

		/* Adjust the CP slot and description information */
		_cpEntry = (J9Object **)( ((U_8 *)_cpEntry) + sizeof(J9RAMConstantPoolItem) );
		_cpEntryCount -= 1;

		_cpDescription >>= J9_CP_BITS_PER_DESCRIPTION;
		_cpDescriptionIndex -= 1;

		/* Determine if the slot should be processed */
		if (slotType == J9CPTYPE_CLASS) {
			classPtr = ((J9RAMClassRef *) slotPtr)->value;
			if (NULL != classPtr) {
				break;
			}
		}
	}
	return classPtr;
}