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/*
* 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)
*
* Copyright (c) 2018 Andrey Semashev
*/
/*!
* \file atomic/detail/fp_ops_emulated.hpp
*
* This header contains emulated (lock-based) implementation of the floating point atomic operations.
*/
#ifndef BOOST_ATOMIC_DETAIL_FP_OPS_EMULATED_HPP_INCLUDED_
#define BOOST_ATOMIC_DETAIL_FP_OPS_EMULATED_HPP_INCLUDED_
#include <cstddef>
#include <boost/memory_order.hpp>
#include <boost/atomic/detail/config.hpp>
#include <boost/atomic/detail/bitwise_fp_cast.hpp>
#include <boost/atomic/detail/fp_operations_fwd.hpp>
#include <boost/atomic/detail/lockpool.hpp>
#ifdef BOOST_HAS_PRAGMA_ONCE
#pragma once
#endif
namespace boost {
namespace atomics {
namespace detail {
//! Generic implementation of floating point operations
template< typename Base, typename Value, std::size_t Size >
struct emulated_fp_operations :
public Base
{
typedef Base base_type;
typedef typename base_type::storage_type storage_type;
typedef Value value_type;
static BOOST_FORCEINLINE value_type fetch_add(storage_type volatile& storage, value_type v, memory_order) BOOST_NOEXCEPT
{
storage_type& s = const_cast< storage_type& >(storage);
lockpool::scoped_lock lock(&storage);
value_type old_val = atomics::detail::bitwise_fp_cast< value_type >(s);
value_type new_val = old_val + v;
s = atomics::detail::bitwise_fp_cast< storage_type >(new_val);
return old_val;
}
static BOOST_FORCEINLINE value_type fetch_sub(storage_type volatile& storage, value_type v, memory_order) BOOST_NOEXCEPT
{
storage_type& s = const_cast< storage_type& >(storage);
lockpool::scoped_lock lock(&storage);
value_type old_val = atomics::detail::bitwise_fp_cast< value_type >(s);
value_type new_val = old_val - v;
s = atomics::detail::bitwise_fp_cast< storage_type >(new_val);
return old_val;
}
};
template< typename Base, typename Value, std::size_t Size >
struct fp_operations< Base, Value, Size, false > :
public emulated_fp_operations< Base, Value, Size >
{
};
} // namespace detail
} // namespace atomics
} // namespace boost
#endif // BOOST_ATOMIC_DETAIL_FP_OPS_EMULATED_HPP_INCLUDED_
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