bitset.hpp

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#ifndef SHARE_VM_JFR_LEAKPROFILER_CHAINS_BITSET_HPP
#define SHARE_VM_JFR_LEAKPROFILER_CHAINS_BITSET_HPP

#include "memory/allocation.hpp"
#include "oops/oopsHierarchy.hpp"
#include "utilities/bitMap.inline.hpp"

class JfrVirtualMemory;
class MemRegion;

class BitSet : public CHeapObj<mtTracing> {
 private:
  JfrVirtualMemory* _vmm;
  const HeapWord* const _region_start;
  BitMap _bits;
  const size_t _region_size;

 public:
  BitSet(const MemRegion& covered_region);
  ~BitSet();

  bool initialize();

  BitMap::idx_t mark_obj(const HeapWord* addr) {
    const BitMap::idx_t bit = addr_to_bit(addr);
    _bits.set_bit(bit);
    return bit;
  }

  BitMap::idx_t mark_obj(oop obj) {
    return mark_obj((HeapWord*)obj);
  }

  bool is_marked(const HeapWord* addr) const {
    return is_marked(addr_to_bit(addr));
  }

  bool is_marked(oop obj) const {
    return is_marked((HeapWord*)obj);
  }

  BitMap::idx_t size() const {
    return _bits.size();
  }

  BitMap::idx_t addr_to_bit(const HeapWord* addr) const {
    return pointer_delta(addr, _region_start) >> LogMinObjAlignment;
  }

  bool is_marked(const BitMap::idx_t bit) const {
    return _bits.at(bit);
  }
};

#endif  // SHARE_VM_JFR_LEAKPROFILER_CHAINS_BITSET_HPP