/*

 * Copyright (c) 2007 Sun Microsystems, Inc.  All Rights Reserved.

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

 *

 * 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 *

 */

template <class T> inline void ParScanWeakRefClosure::do_oop_work(T* p) {

  assert (!oopDesc::is_null(*p), "null weak reference?");

  oop obj = oopDesc::load_decode_heap_oop_not_null(p);

  // weak references are sometimes scanned twice; must check

  // that to-space doesn't already contain this object

  if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) {

    // we need to ensure that it is copied (see comment in

    // ParScanClosure::do_oop_work).

    klassOop objK = obj->klass();

    markOop m = obj->mark();

    oop new_obj;

    if (m->is_marked()) { // Contains forwarding pointer.

      new_obj = ParNewGeneration::real_forwardee(obj);

    } else {

      size_t obj_sz = obj->size_given_klass(objK->klass_part());

      new_obj = ((ParNewGeneration*)_g)->copy_to_survivor_space(_par_scan_state,

                                                                obj, obj_sz, m);

    }

    oopDesc::encode_store_heap_oop_not_null(p, new_obj);

  }

}

inline void ParScanWeakRefClosure::do_oop_nv(oop* p)       { ParScanWeakRefClosure::do_oop_work(p); }

inline void ParScanWeakRefClosure::do_oop_nv(narrowOop* p) { ParScanWeakRefClosure::do_oop_work(p); }

template <class T> inline void ParScanClosure::par_do_barrier(T* p) {

  assert(generation()->is_in_reserved(p), "expected ref in generation");

  assert(!oopDesc::is_null(*p), "expected non-null object");

  oop obj = oopDesc::load_decode_heap_oop_not_null(p);

  // If p points to a younger generation, mark the card.

  if ((HeapWord*)obj < gen_boundary()) {

    rs()->write_ref_field_gc_par(p, obj);

  }

}

template <class T>

inline void ParScanClosure::do_oop_work(T* p,

                                        bool gc_barrier,

                                        bool root_scan) {

  assert((!Universe::heap()->is_in_reserved(p) ||

          generation()->is_in_reserved(p))

         && (generation()->level() == 0 || gc_barrier),

         "The gen must be right, and we must be doing the barrier "

         "in older generations.");

  T heap_oop = oopDesc::load_heap_oop(p);

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

    oop obj = oopDesc::decode_heap_oop_not_null(heap_oop);

    if ((HeapWord*)obj < _boundary) {

      assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?");

      // OK, we need to ensure that it is copied.

      // We read the klass and mark in this order, so that we can reliably

      // get the size of the object: if the mark we read is not a

      // forwarding pointer, then the klass is valid: the klass is only

      // overwritten with an overflow next pointer after the object is

      // forwarded.

      klassOop objK = obj->klass();

      markOop m = obj->mark();

      oop new_obj;

      if (m->is_marked()) { // Contains forwarding pointer.

        new_obj = ParNewGeneration::real_forwardee(obj);

        oopDesc::encode_store_heap_oop_not_null(p, new_obj);

      } else {

        size_t obj_sz = obj->size_given_klass(objK->klass_part());

        new_obj = _g->copy_to_survivor_space(_par_scan_state, obj, obj_sz, m);

        oopDesc::encode_store_heap_oop_not_null(p, new_obj);

        if (root_scan) {

          // This may have pushed an object.  If we have a root

          // category with a lot of roots, can't let the queue get too

          // full:

          (void)_par_scan_state->trim_queues(10 * ParallelGCThreads);

        }

      }

      if (gc_barrier) {

        // Now call parent closure

        par_do_barrier(p);

      }

    }

  }

}

inline void ParScanWithBarrierClosure::do_oop_nv(oop* p)       { ParScanClosure::do_oop_work(p, true, false); }

inline void ParScanWithBarrierClosure::do_oop_nv(narrowOop* p) { ParScanClosure::do_oop_work(p, true, false); }

inline void ParScanWithoutBarrierClosure::do_oop_nv(oop* p)       { ParScanClosure::do_oop_work(p, false, false); }

inline void ParScanWithoutBarrierClosure::do_oop_nv(narrowOop* p) { ParScanClosure::do_oop_work(p, false, false); }