/*

 * Copyright (c) 2018, 2019, Red Hat, Inc. All rights reserved.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * 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,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#ifndef SHARE_GC_SHENANDOAH_SHENANDOAHMARKINGCONTEXT_HPP

#define SHARE_GC_SHENANDOAH_SHENANDOAHMARKINGCONTEXT_HPP

#include "gc/shared/markBitMap.hpp"

#include "memory/allocation.hpp"

#include "memory/memRegion.hpp"

#include "oops/oopsHierarchy.hpp"

/**

 * Encapsulate a marking bitmap with the top-at-mark-start and top-bitmaps array.

 */

class ShenandoahMarkingContext : public CHeapObj<mtGC> {

private:

  MarkBitMap _mark_bit_map;

  HeapWord** const _top_bitmaps;

  HeapWord** const _top_at_mark_starts_base;

  HeapWord** const _top_at_mark_starts;

  ShenandoahSharedFlag _is_complete;

public:

  ShenandoahMarkingContext(MemRegion heap_region, MemRegion bitmap_region, size_t num_regions);

  /*

   * Marks the object. Returns true if the object has not been marked before and has

   * been marked by this thread. Returns false if the object has already been marked,

   * or if a competing thread succeeded in marking this object.

   */

  inline bool mark(oop obj);

  inline bool is_marked(oop obj) const;

  inline bool allocated_after_mark_start(HeapWord* addr) const;

  inline MarkBitMap* mark_bit_map();

  HeapWord* top_at_mark_start(ShenandoahHeapRegion* r) const;

  void capture_top_at_mark_start(ShenandoahHeapRegion* r);

  void reset_top_at_mark_start(ShenandoahHeapRegion* r);

  void initialize_top_at_mark_start(ShenandoahHeapRegion* r);

  void reset_top_bitmap(ShenandoahHeapRegion *r);

  void clear_bitmap(ShenandoahHeapRegion *r);

  bool is_bitmap_clear() const;

  bool is_bitmap_clear_range(HeapWord* start, HeapWord* end) const;

  bool is_complete();

  void mark_complete();

  void mark_incomplete();

};

#endif // SHARE_GC_SHENANDOAH_SHENANDOAHMARKINGCONTEXT_HPP