src/hotspot/share/utilities/objectBitSet.inline.hpp

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#ifndef SHARE_UTILITIES_OBJECTBITSET_INLINE_HPP
#define SHARE_UTILITIES_OBJECTBITSET_INLINE_HPP

#include "utilities/objectBitSet.hpp"

#include "memory/memRegion.hpp"
#include "utilities/bitMap.inline.hpp"

template<MEMFLAGS F>
ObjectBitSet<F>::BitMapFragment::BitMapFragment(uintptr_t granule, BitMapFragment* next) :
        _bits(_bitmap_granularity_size >> LogMinObjAlignmentInBytes, F, true /* clear */),
        _next(next) {
}

template<MEMFLAGS F>
ObjectBitSet<F>::ObjectBitSet() :
        _bitmap_fragments(32, 8*K),
        _fragment_list(nullptr),
        _last_fragment_bits(nullptr),
        _last_fragment_granule(UINTPTR_MAX) {
}

template<MEMFLAGS F>
ObjectBitSet<F>::~ObjectBitSet() {
  BitMapFragment* current = _fragment_list;
  while (current != nullptr) {
    BitMapFragment* next = current->next();
    delete current;
    current = next;
  }
  // destructors for ResourceHashtable base deletes nodes, and
  // ResizeableResourceHashtableStorage deletes the table.
}

template<MEMFLAGS F>
inline BitMap::idx_t ObjectBitSet<F>::addr_to_bit(uintptr_t addr) const {
  return (addr & _bitmap_granularity_mask) >> LogMinObjAlignmentInBytes;
}

template<MEMFLAGS F>
inline CHeapBitMap* ObjectBitSet<F>::get_fragment_bits(uintptr_t addr) {
  uintptr_t granule = addr >> _bitmap_granularity_shift;
  if (granule == _last_fragment_granule) {
    return _last_fragment_bits;
  }
  CHeapBitMap* bits = nullptr;

  CHeapBitMap** found = _bitmap_fragments.get(granule);
  if (found != nullptr) {
    bits = *found;
  } else {
    BitMapFragment* fragment = new BitMapFragment(granule, _fragment_list);
    bits = fragment->bits();
    _fragment_list = fragment;
    _bitmap_fragments.put(granule, bits);
    _bitmap_fragments.maybe_grow();
  }

  _last_fragment_bits = bits;
  _last_fragment_granule = granule;

  return bits;
}

template<MEMFLAGS F>
inline void ObjectBitSet<F>::mark_obj(uintptr_t addr) {
  CHeapBitMap* bits = get_fragment_bits(addr);
  const BitMap::idx_t bit = addr_to_bit(addr);
  bits->set_bit(bit);
}

template<MEMFLAGS F>
inline bool ObjectBitSet<F>::is_marked(uintptr_t addr) {
  CHeapBitMap* bits = get_fragment_bits(addr);
  const BitMap::idx_t bit = addr_to_bit(addr);
  return bits->at(bit);
}

#endif // SHARE_UTILITIES_OBJECTBITSET_INLINE_HPP