/*

 * Copyright (c) 2018, 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_SHENANDOAHTRAVERSALGC_INLINE_HPP

#define SHARE_GC_SHENANDOAH_SHENANDOAHTRAVERSALGC_INLINE_HPP

#include "gc/shenandoah/shenandoahAsserts.hpp"

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

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

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

#include "gc/shenandoah/shenandoahStringDedup.hpp"

#include "gc/shenandoah/shenandoahTraversalGC.hpp"

#include "gc/shenandoah/shenandoahTaskqueue.hpp"

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

#include "oops/compressedOops.inline.hpp"

#include "oops/oop.inline.hpp"

template <class T, bool STRING_DEDUP, bool DEGEN, bool ATOMIC_UPDATE>

void ShenandoahTraversalGC::process_oop(T* p, Thread* thread, ShenandoahObjToScanQueue* queue, ShenandoahMarkingContext* const mark_context) {

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

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

    oop obj = CompressedOops::decode_not_null(o);

    if (DEGEN) {

      assert(!ATOMIC_UPDATE, "Degen path assumes non-atomic updates");

      oop forw = ShenandoahBarrierSet::resolve_forwarded_not_null(obj);

      if (obj != forw) {

        // Update reference.

        RawAccess<IS_NOT_NULL>::oop_store(p, forw);

      }

      obj = forw;

    } else if (_heap->in_collection_set(obj)) {

      oop forw = ShenandoahBarrierSet::resolve_forwarded_not_null(obj);

      if (obj == forw) {

        forw = _heap->evacuate_object(obj, thread);

      }

      shenandoah_assert_forwarded_except(p, obj, _heap->cancelled_gc());

      // Update reference.

      if (ATOMIC_UPDATE) {

        ShenandoahHeap::cas_oop(forw, p, obj);

      } else {

        RawAccess<IS_NOT_NULL>::oop_store(p, forw);

      }

      obj = forw;

    }

    shenandoah_assert_not_forwarded(p, obj);

    shenandoah_assert_not_in_cset_except(p, obj, _heap->cancelled_gc());

    if (mark_context->mark(obj)) {

      bool succeeded = queue->push(ShenandoahMarkTask(obj));

      assert(succeeded, "must succeed to push to task queue");

      if (STRING_DEDUP && ShenandoahStringDedup::is_candidate(obj) && !_heap->cancelled_gc()) {

        assert(ShenandoahStringDedup::is_enabled(), "Must be enabled");

        // Only dealing with to-space string, so that we can avoid evac-oom protocol, which is costly here.

        shenandoah_assert_not_in_cset(p, obj);

        ShenandoahStringDedup::enqueue_candidate(obj);

      }

    }

  }

}

#endif // SHARE_GC_SHENANDOAH_SHENANDOAHTRAVERSALGC_INLINE_HPP