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#ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_AIX_HPP_INCLUDED
#define BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_AIX_HPP_INCLUDED

//
//  detail/sp_counted_base_aix.hpp
//   based on: detail/sp_counted_base_w32.hpp
//
//  Copyright (c) 2001, 2002, 2003 Peter Dimov and Multi Media Ltd.
//  Copyright 2004-2005 Peter Dimov
//  Copyright 2006 Michael van der Westhuizen
//
//  Distributed under the Boost Software License, Version 1.0. (See
//  accompanying file LICENSE_1_0.txt or copy at
//  http://www.boost.org/LICENSE_1_0.txt)
//
//
//  Lock-free algorithm by Alexander Terekhov
//
//  Thanks to Ben Hitchings for the #weak + (#shared != 0)
//  formulation
//

#include <boost/detail/sp_typeinfo.hpp>
#include <builtins.h>
#include <sys/atomic_op.h>

namespace boost
{

namespace detail
{

inline void atomic_increment( int32_t* pw )
{
    // ++*pw;

    fetch_and_add( pw, 1 );
}

inline int32_t atomic_decrement( int32_t * pw )
{
    // return --*pw;

    int32_t originalValue;

    __lwsync();
    originalValue = fetch_and_add( pw, -1 );
    __isync();

    return (originalValue - 1);
}

inline int32_t atomic_conditional_increment( int32_t * pw )
{
    // if( *pw != 0 ) ++*pw;
    // return *pw;

    int32_t tmp = fetch_and_add( pw, 0 );
    for( ;; )
    {
        if( tmp == 0 ) return 0;
        if( compare_and_swap( pw, &tmp, tmp + 1 ) ) return (tmp + 1);
    }
}

class sp_counted_base
{
private:

    sp_counted_base( sp_counted_base const & );
    sp_counted_base & operator= ( sp_counted_base const & );

    int32_t use_count_;        // #shared
    int32_t weak_count_;       // #weak + (#shared != 0)

public:

    sp_counted_base(): use_count_( 1 ), weak_count_( 1 )
    {
    }