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 * 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.

 *

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#include "gc/g1/g1BarrierSet.hpp"

#include "gc/g1/g1CardTable.hpp"

#include "gc/shared/accessBarrierSupport.inline.hpp"

#include "oops/access.inline.hpp"

#include "oops/compressedOops.inline.hpp"

#include "oops/oop.hpp"

template <DecoratorSet decorators, typename T>

inline void G1BarrierSet::write_ref_field_pre(T* field) {

  if (HasDecorator<decorators, IS_DEST_UNINITIALIZED>::value ||

      HasDecorator<decorators, AS_NO_KEEPALIVE>::value) {

    return;

  }

  T heap_oop = RawAccess<MO_VOLATILE>::oop_load(field);

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

    enqueue(CompressedOops::decode_not_null(heap_oop));

  }

}

template <DecoratorSet decorators, typename T>

inline void G1BarrierSet::write_ref_field_post(T* field, oop new_val) {

  volatile jbyte* byte = _card_table->byte_for(field);

  if (*byte != G1CardTable::g1_young_card_val()) {

    // Take a slow path for cards in old

    write_ref_field_post_slow(byte);

  }

}

inline void G1BarrierSet::enqueue_if_weak(DecoratorSet decorators, oop value) {

  assert((decorators & ON_UNKNOWN_OOP_REF) == 0, "Reference strength must be known");

  // Loading from a weak or phantom reference needs enqueueing, as

  // the object may not have been reachable (part of the snapshot)

  // when marking started.

  const bool on_strong_oop_ref = (decorators & ON_STRONG_OOP_REF) != 0;

  const bool peek              = (decorators & AS_NO_KEEPALIVE) != 0;

  const bool needs_enqueue     = (!peek && !on_strong_oop_ref);

  if (needs_enqueue && value != NULL) {

    enqueue(value);

  }

}

template <DecoratorSet decorators, typename BarrierSetT>

template <typename T>

inline oop G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::

oop_load_not_in_heap(T* addr) {

  oop value = ModRef::oop_load_not_in_heap(addr);

  enqueue_if_weak(decorators, value);

  return value;

}

template <DecoratorSet decorators, typename BarrierSetT>

template <typename T>

inline oop G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::

oop_load_in_heap(T* addr) {

  oop value = ModRef::oop_load_in_heap(addr);

  enqueue_if_weak(decorators, value);

  return value;

}

template <DecoratorSet decorators, typename BarrierSetT>

inline oop G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::

oop_load_in_heap_at(oop base, ptrdiff_t offset) {

  oop value = ModRef::oop_load_in_heap_at(base, offset);

  enqueue_if_weak(AccessBarrierSupport::resolve_possibly_unknown_oop_ref_strength<decorators>(base, offset), value);

  return value;

}

template <DecoratorSet decorators, typename BarrierSetT>

template <typename T>

inline void G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::

oop_store_not_in_heap(T* addr, oop new_value) {

  // Apply SATB barriers for all non-heap references, to allow

  // concurrent scanning of such references.

  G1BarrierSet *bs = barrier_set_cast<G1BarrierSet>(BarrierSet::barrier_set());

  bs->write_ref_field_pre<decorators>(addr);

  Raw::oop_store(addr, new_value);

}