/*

 * Copyright (c) 2018, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "code/compiledMethod.hpp"

#include "code/nmethod.hpp"

#include "gc/shared/gcBehaviours.hpp"

IsUnloadingBehaviour* IsUnloadingBehaviour::_current = NULL;

class IsCompiledMethodUnloadingOopClosure: public OopClosure {

  BoolObjectClosure *_cl;

  bool _is_unloading;

public:

  IsCompiledMethodUnloadingOopClosure(BoolObjectClosure* cl)

    : _cl(cl),

      _is_unloading(false)

  { }

  virtual void do_oop(oop* p) {

    if (_is_unloading) {

      return;

    }

    oop obj = *p;

    if (obj == NULL) {

      return;

    }

    if (!_cl->do_object_b(obj)) {

      _is_unloading = true;

    }

  }

  virtual void do_oop(narrowOop* p) {

    ShouldNotReachHere();

  }

  bool is_unloading() const {

    return _is_unloading;

  }

};

bool ClosureIsUnloadingBehaviour::is_unloading(CompiledMethod* cm) const {

  if (cm->is_nmethod()) {

    IsCompiledMethodUnloadingOopClosure cl(_cl);

    static_cast<nmethod*>(cm)->oops_do(&cl, true /* allow_dead */);

    return cl.is_unloading();

  } else {

    return false;

  }

}