/*

 * Copyright (c) 2013, 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_SHENANDOAHBARRIERSETCLONE_INLINE_HPP

#define SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSETCLONE_INLINE_HPP

#include "gc/shenandoah/shenandoahBarrierSet.inline.hpp"

#include "gc/shenandoah/shenandoahCollectionSet.inline.hpp"

#include "gc/shenandoah/shenandoahEvacOOMHandler.hpp"

#include "gc/shenandoah/shenandoahHeap.inline.hpp"

#include "memory/iterator.hpp"

#include "oops/access.hpp"

#include "oops/compressedOops.hpp"

template <bool EVAC, bool ENQUEUE>

class ShenandoahUpdateRefsForOopClosure: public BasicOopIterateClosure {

private:

  ShenandoahHeap* const _heap;

  ShenandoahBarrierSet* const _bs;

  const ShenandoahCollectionSet* const _cset;

  Thread* const _thread;

  template <class T>

  inline void do_oop_work(T* p) {

    T o = RawAccess<>::oop_load(p);

    if (!CompressedOops::is_null(o)) {

      oop obj = CompressedOops::decode_not_null(o);

      if (_cset->is_in((HeapWord *)obj)) {

        oop fwd = _bs->resolve_forwarded_not_null(obj);

        if (EVAC && obj == fwd) {

          fwd = _heap->evacuate_object(obj, _thread);

        }

        if (ENQUEUE) {

          _bs->enqueue(fwd);

        }

        assert(obj != fwd || _heap->cancelled_gc(), "must be forwarded");

        ShenandoahHeap::cas_oop(fwd, p, o);

      }

    }

  }

public:

  ShenandoahUpdateRefsForOopClosure() :

          _heap(ShenandoahHeap::heap()),

          _bs(ShenandoahBarrierSet::barrier_set()),

          _cset(_heap->collection_set()),

          _thread(Thread::current()) {

  }

  virtual void do_oop(oop* p)       { do_oop_work(p); }

  virtual void do_oop(narrowOop* p) { do_oop_work(p); }

};

void ShenandoahBarrierSet::clone_barrier(oop obj) {

  assert(ShenandoahCloneBarrier, "only get here with clone barriers enabled");

  assert(_heap->has_forwarded_objects(), "only when heap is unstable");

  // This is called for cloning an object (see jvm.cpp) after the clone

  // has been made. We are not interested in any 'previous value' because

  // it would be NULL in any case. But we *are* interested in any oop*

  // that potentially need to be updated.

  shenandoah_assert_correct(NULL, obj);

  if (_heap->is_evacuation_in_progress()) {

    ShenandoahEvacOOMScope evac_scope;

    ShenandoahUpdateRefsForOopClosure</* evac = */ true, /* enqueue */ false> cl;

    obj->oop_iterate(&cl);

  } else if (_heap->is_concurrent_traversal_in_progress()) {

    ShenandoahEvacOOMScope evac_scope;

    ShenandoahUpdateRefsForOopClosure</* evac = */ true, /* enqueue */ true> cl;

    obj->oop_iterate(&cl);

  } else {

    ShenandoahUpdateRefsForOopClosure</* evac = */ false, /* enqueue */ false> cl;

    obj->oop_iterate(&cl);

  }

}

#endif // SHARE_GC_SHENANDOAH_SHENANDOAHBARRIERSETCLONE_INLINE_HPP