/*

 * Copyright 2001-2008 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.

 *

 */

inline OopsInGenClosure::OopsInGenClosure(Generation* gen) :

  OopClosure(gen->ref_processor()), _orig_gen(gen), _rs(NULL) {

  set_generation(gen);

}

inline void OopsInGenClosure::set_generation(Generation* gen) {

  _gen = gen;

  _gen_boundary = _gen->reserved().start();

  // Barrier set for the heap, must be set after heap is initialized

  if (_rs == NULL) {

    GenRemSet* rs = SharedHeap::heap()->rem_set();

    assert(rs->rs_kind() == GenRemSet::CardTable, "Wrong rem set kind");

    _rs = (CardTableRS*)rs;

  }

}

template <class T> inline void OopsInGenClosure::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->inline_write_ref_field_gc(p, obj);

  }

}

inline void OopsInGenClosure::par_do_barrier(oop* p) {

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

  oop obj = *p;

  assert(obj != NULL, "expected non-null object");

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

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

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

  }

}

// NOTE! Any changes made here should also be made

// in FastScanClosure::do_oop_work()

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

  T heap_oop = oopDesc::load_heap_oop(p);

  // Should we copy the obj?

  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?");

      oop new_obj = obj->is_forwarded() ? obj->forwardee()

                                        : _g->copy_to_survivor_space(obj);

      oopDesc::encode_store_heap_oop_not_null(p, new_obj);

    }

    if (_gc_barrier) {

      // Now call parent closure

      do_barrier(p);

    }

  }

}

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

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

// NOTE! Any changes made here should also be made

// in ScanClosure::do_oop_work()

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

  T heap_oop = oopDesc::load_heap_oop(p);

  // Should we copy the obj?

  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?");

      oop new_obj = obj->is_forwarded() ? obj->forwardee()

                                        : _g->copy_to_survivor_space(obj);

      oopDesc::encode_store_heap_oop_not_null(p, new_obj);

      if (_gc_barrier) {

        // Now call parent closure

        do_barrier(p);

      }

    }

  }

}

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

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

// Note similarity to ScanClosure; the difference is that

// the barrier set is taken care of outside this closure.

template <class T> inline void ScanWeakRefClosure::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)) {

    oop new_obj = obj->is_forwarded() ? obj->forwardee()

                                      : _g->copy_to_survivor_space(obj);

    oopDesc::encode_store_heap_oop_not_null(p, new_obj);

  }

}

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

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