lock_free_internal.hpp

/*  
 * Copyright (c) 2009 Carnegie Mellon University. 
 *     All rights reserved.
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an "AS
 *  IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 *  express or implied.  See the License for the specific language
 *  governing permissions and limitations under the License.
 *
 * For more about this software visit:
 *
 *      http://www.graphlab.ml.cmu.edu
 *
 */


#ifndef GRAPHLAB_UTIL_LOCK_FREE_INTERNAL_HPP
#define GRAPHLAB_UTIL_LOCK_FREE_INTERNAL_HPP

#include <graphlab/util/generics/integer_selector.hpp>

namespace graphlab {
namespace lock_free_internal {

template <typename index_type>
union reference_with_counter {
  struct {
    index_type val;
    index_type counter;
  } q;
  index_type& value() {
    return q.val;
  }
  index_type& counter() {
    return q.counter;
  }
  typename u_integer_selector<sizeof(index_type) * 2>::integer_type combined;
};
  
}
}
#endif