| /* |
| * 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/bitwise_fp_cast.hpp |
| * |
| * This header defines \c bitwise_fp_cast used to convert between storage and floating point value types |
| */ |
| |
| #ifndef BOOST_ATOMIC_DETAIL_BITWISE_FP_CAST_HPP_INCLUDED_ |
| #define BOOST_ATOMIC_DETAIL_BITWISE_FP_CAST_HPP_INCLUDED_ |
| |
| #include <cstddef> |
| #include <boost/atomic/detail/config.hpp> |
| #include <boost/atomic/detail/float_sizes.hpp> |
| #include <boost/atomic/detail/bitwise_cast.hpp> |
| #include <boost/atomic/detail/header.hpp> |
| |
| #ifdef BOOST_HAS_PRAGMA_ONCE |
| #pragma once |
| #endif |
| |
| namespace boost { |
| namespace atomics { |
| namespace detail { |
| |
| /*! |
| * \brief The type trait returns the size of the value of the specified floating point type |
| * |
| * This size may be less than <tt>sizeof(T)</tt> if the implementation uses padding bytes for a particular FP type. This is |
| * often the case with 80-bit extended double, which is stored in 12 or 16 bytes with padding filled with garbage. |
| */ |
| template< typename T > |
| struct value_sizeof |
| { |
| static BOOST_CONSTEXPR_OR_CONST std::size_t value = sizeof(T); |
| }; |
| |
| #if defined(BOOST_ATOMIC_DETAIL_SIZEOF_FLOAT_VALUE) |
| template< > |
| struct value_sizeof< float > |
| { |
| static BOOST_CONSTEXPR_OR_CONST std::size_t value = BOOST_ATOMIC_DETAIL_SIZEOF_FLOAT_VALUE; |
| }; |
| #endif |
| |
| #if defined(BOOST_ATOMIC_DETAIL_SIZEOF_DOUBLE_VALUE) |
| template< > |
| struct value_sizeof< double > |
| { |
| static BOOST_CONSTEXPR_OR_CONST std::size_t value = BOOST_ATOMIC_DETAIL_SIZEOF_DOUBLE_VALUE; |
| }; |
| #endif |
| |
| #if defined(BOOST_ATOMIC_DETAIL_SIZEOF_LONG_DOUBLE_VALUE) |
| template< > |
| struct value_sizeof< long double > |
| { |
| static BOOST_CONSTEXPR_OR_CONST std::size_t value = BOOST_ATOMIC_DETAIL_SIZEOF_LONG_DOUBLE_VALUE; |
| }; |
| #endif |
| |
| template< typename T > |
| struct value_sizeof< const T > : value_sizeof< T > {}; |
| |
| template< typename T > |
| struct value_sizeof< volatile T > : value_sizeof< T > {}; |
| |
| template< typename T > |
| struct value_sizeof< const volatile T > : value_sizeof< T > {}; |
| |
| |
| template< typename To, typename From > |
| BOOST_FORCEINLINE To bitwise_fp_cast(From const& from) BOOST_NOEXCEPT |
| { |
| return atomics::detail::bitwise_cast< To, atomics::detail::value_sizeof< From >::value >(from); |
| } |
| |
| } // namespace detail |
| } // namespace atomics |
| } // namespace boost |
| |
| #include <boost/atomic/detail/footer.hpp> |
| |
| #endif // BOOST_ATOMIC_DETAIL_BITWISE_FP_CAST_HPP_INCLUDED_ |