#ifndef BOOST_ENDIAN_DETAIL_ENDIAN_REVERSE_HPP_INCLUDED

#define BOOST_ENDIAN_DETAIL_ENDIAN_REVERSE_HPP_INCLUDED

// Copyright 2019, 2020 Peter Dimov

// Distributed under the Boost Software License, Version 1.0.

// https://www.boost.org/LICENSE_1_0.txt

#include <boost/endian/detail/integral_by_size.hpp>

#include <boost/endian/detail/intrinsic.hpp>

#include <boost/endian/detail/is_scoped_enum.hpp>

#include <boost/endian/detail/is_integral.hpp>

#include <boost/endian/detail/static_assert.hpp>

#include <boost/config.hpp>

#include <type_traits>

#include <cstdint>

#include <cstddef>

#include <cstring>

#if defined(BOOST_ENDIAN_NO_INTRINSICS)

# if defined(BOOST_NO_CXX14_CONSTEXPR)

#  define BOOST_ENDIAN_CONSTEXPR

# else

#  define BOOST_ENDIAN_CONSTEXPR constexpr

# endif

#else

# if defined(BOOST_ENDIAN_CONSTEXPR_INTRINSICS)

#  define BOOST_ENDIAN_CONSTEXPR BOOST_CONSTEXPR

# else

#  define BOOST_ENDIAN_CONSTEXPR

# endif

#endif

namespace boost

{

namespace endian

{

namespace detail

{

//  -- portable approach suggested by tymofey, with avoidance of undefined behavior

//     as suggested by Giovanni Piero Deretta, with a further refinement suggested

//     by Pyry Jahkola.

//  -- intrinsic approach suggested by reviewers, and by David Stone, who provided

//     his Boost licensed macro implementation (detail/intrinsic.hpp)

inline std::uint8_t BOOST_CONSTEXPR endian_reverse_impl( std::uint8_t x ) BOOST_NOEXCEPT

{

    return x;

}

inline std::uint16_t BOOST_ENDIAN_CONSTEXPR endian_reverse_impl( std::uint16_t x ) BOOST_NOEXCEPT

{

#ifdef BOOST_ENDIAN_NO_INTRINSICS

    return (x << 8) | (x >> 8);

#else

    return BOOST_ENDIAN_INTRINSIC_BYTE_SWAP_2(x);

#endif

}

inline std::uint32_t BOOST_ENDIAN_CONSTEXPR endian_reverse_impl( std::uint32_t x ) BOOST_NOEXCEPT

{

#ifdef BOOST_ENDIAN_NO_INTRINSICS

    std::uint32_t step16 = x << 16 | x >> 16;

    return ((step16 << 8) & 0xff00ff00) | ((step16 >> 8) & 0x00ff00ff);

#else

    return BOOST_ENDIAN_INTRINSIC_BYTE_SWAP_4(x);

#endif

}

inline std::uint64_t BOOST_ENDIAN_CONSTEXPR endian_reverse_impl( std::uint64_t x ) BOOST_NOEXCEPT

{

#ifdef BOOST_ENDIAN_NO_INTRINSICS

    std::uint64_t step32 = x << 32 | x >> 32;

    std::uint64_t step16 = (step32 & 0x0000FFFF0000FFFFULL) << 16 | (step32 & 0xFFFF0000FFFF0000ULL) >> 16;

    return (step16 & 0x00FF00FF00FF00FFULL) << 8 | (step16 & 0xFF00FF00FF00FF00ULL) >> 8;

#else

    return BOOST_ENDIAN_INTRINSIC_BYTE_SWAP_8(x);

# endif

}

#if defined(__SIZEOF_INT128__)

inline __uint128_t BOOST_ENDIAN_CONSTEXPR endian_reverse_impl( __uint128_t x ) BOOST_NOEXCEPT

{

    return endian_reverse_impl( static_cast<std::uint64_t>( x >> 64 ) ) |

        static_cast<__uint128_t>( endian_reverse_impl( static_cast<std::uint64_t>( x ) ) ) << 64;

}

#endif

// is_endian_reversible

template<class T> struct is_endian_reversible: std::integral_constant<bool,

    (is_integral<T>::value && !std::is_same<T, bool>::value) || is_scoped_enum<T>::value>

{

};

// is_endian_reversible_inplace

template<class T> struct is_endian_reversible_inplace: std::integral_constant<bool,

    is_integral<T>::value || std::is_enum<T>::value || std::is_same<T, float>::value || std::is_same<T, double>::value>

{

};

} // namespace detail

// Requires:

//   T is non-bool integral or scoped enumeration type

template<class T> inline BOOST_CONSTEXPR

    typename std::enable_if< !std::is_class<T>::value, T >::type

    endian_reverse( T x ) BOOST_NOEXCEPT

{

    BOOST_ENDIAN_STATIC_ASSERT( detail::is_endian_reversible<T>::value );

    typedef typename detail::integral_by_size< sizeof(T) >::type uintN_t;

    return static_cast<T>( detail::endian_reverse_impl( static_cast<uintN_t>( x ) ) );

}

// Requires:

//   T is integral, enumeration, float or double

template<class T> inline

    typename std::enable_if< !std::is_class<T>::value >::type

    endian_reverse_inplace( T & x ) BOOST_NOEXCEPT

{

    BOOST_ENDIAN_STATIC_ASSERT( detail::is_endian_reversible_inplace<T>::value );

    typename detail::integral_by_size< sizeof(T) >::type x2;

    std::memcpy( &x2, &x, sizeof(T) );

    x2 = detail::endian_reverse_impl( x2 );

    std::memcpy( &x, &x2, sizeof(T) );

}

Unexecuted instantiation: _ZN5boost6endian22endian_reverse_inplaceItEENSt3__19enable_ifIXntsr3std8is_classIT_EE5valueEvE4typeERS4_

Unexecuted instantiation: _ZN5boost6endian22endian_reverse_inplaceIjEENSt3__19enable_ifIXntsr3std8is_classIT_EE5valueEvE4typeERS4_

Unexecuted instantiation: _ZN5boost6endian22endian_reverse_inplaceImEENSt3__19enable_ifIXntsr3std8is_classIT_EE5valueEvE4typeERS4_

// Default implementation for user-defined types

template<class T> inline

    typename std::enable_if< std::is_class<T>::value >::type

    endian_reverse_inplace( T & x ) BOOST_NOEXCEPT

{

    x = endian_reverse( x );

}

// endian_reverse_inplace for arrays

template<class T, std::size_t N>

inline void endian_reverse_inplace( T (&x)[ N ] ) BOOST_NOEXCEPT

{

    for( std::size_t i = 0; i < N; ++i )

    {

        endian_reverse_inplace( x[i] );

    }

}

} // namespace endian

} // namespace boost

#endif  // BOOST_ENDIAN_DETAIL_ENDIAN_REVERSE_HPP_INCLUDED