/*

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

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 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

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#ifndef SHARE_GC_PARALLEL_IMMUTABLESPACE_HPP

#define SHARE_GC_PARALLEL_IMMUTABLESPACE_HPP

#include "memory/iterator.hpp"

// An ImmutableSpace is a viewport into a contiguous range

// (or subrange) of previously allocated objects.

// Invariant: bottom() and end() are on page_size boundaries and

// bottom() <= end()

class ImmutableSpace: public CHeapObj<mtGC> {

  friend class VMStructs;

 protected:

  HeapWord* _bottom;

  HeapWord* _end;

 public:

  ImmutableSpace()                   { _bottom = NULL; _end = NULL;  }

  HeapWord* bottom() const           { return _bottom;               }

  HeapWord* end() const              { return _end;                  }

  MemRegion region() const { return MemRegion(bottom(), end()); }

  // Initialization

  void initialize(MemRegion mr);

  bool contains(const void* p) const { return _bottom <= p && p < _end; }

  // Size computations.  Sizes are in bytes.

  size_t capacity_in_bytes() const            { return capacity_in_words() * HeapWordSize; }

  // Size computations.  Sizes are in heapwords.

  size_t capacity_in_words() const                { return pointer_delta(end(), bottom()); }

  virtual size_t capacity_in_words(Thread*) const { return capacity_in_words(); }

  // Iteration.

  virtual void oop_iterate(OopIterateClosure* cl);

  virtual void object_iterate(ObjectClosure* cl);

  // Debugging

  virtual void print() const            PRODUCT_RETURN;

  virtual void print_short() const      PRODUCT_RETURN;

  virtual void verify();

};

#endif // SHARE_GC_PARALLEL_IMMUTABLESPACE_HPP