1*4824e7fdSDimitry Andric // -*- C++ -*- 2*4824e7fdSDimitry Andric //===----------------------------------------------------------------------===// 3*4824e7fdSDimitry Andric // 4*4824e7fdSDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5*4824e7fdSDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 6*4824e7fdSDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7*4824e7fdSDimitry Andric // 8*4824e7fdSDimitry Andric //===----------------------------------------------------------------------===// 9*4824e7fdSDimitry Andric 10*4824e7fdSDimitry Andric #ifndef _LIBCPP___BIT_BYTESWAP_H 11*4824e7fdSDimitry Andric #define _LIBCPP___BIT_BYTESWAP_H 12*4824e7fdSDimitry Andric 13*4824e7fdSDimitry Andric #include <__concepts/arithmetic.h> 14*4824e7fdSDimitry Andric #include <__config> 15*4824e7fdSDimitry Andric #include <cstdint> 16*4824e7fdSDimitry Andric #include <cstdlib> 17*4824e7fdSDimitry Andric 18*4824e7fdSDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 19*4824e7fdSDimitry Andric # pragma GCC system_header 20*4824e7fdSDimitry Andric #endif 21*4824e7fdSDimitry Andric 22*4824e7fdSDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD 23*4824e7fdSDimitry Andric 24*4824e7fdSDimitry Andric #if _LIBCPP_STD_VER > 20 && !defined(_LIBCPP_HAS_NO_CONCEPTS) 25*4824e7fdSDimitry Andric 26*4824e7fdSDimitry Andric template <integral _Tp> 27*4824e7fdSDimitry Andric _LIBCPP_HIDE_FROM_ABI constexpr _Tp byteswap(_Tp __val) noexcept { 28*4824e7fdSDimitry Andric 29*4824e7fdSDimitry Andric if constexpr (sizeof(_Tp) == 1) { 30*4824e7fdSDimitry Andric return __val; 31*4824e7fdSDimitry Andric } else if constexpr (sizeof(_Tp) == 2) { 32*4824e7fdSDimitry Andric return __builtin_bswap16(__val); 33*4824e7fdSDimitry Andric } else if constexpr (sizeof(_Tp) == 4) { 34*4824e7fdSDimitry Andric return __builtin_bswap32(__val); 35*4824e7fdSDimitry Andric } else if constexpr (sizeof(_Tp) == 8) { 36*4824e7fdSDimitry Andric return __builtin_bswap64(__val); 37*4824e7fdSDimitry Andric #ifndef _LIBCPP_HAS_NO_INT128 38*4824e7fdSDimitry Andric } else if constexpr (sizeof(_Tp) == 16) { 39*4824e7fdSDimitry Andric #if __has_builtin(__builtin_bswap128) 40*4824e7fdSDimitry Andric return __builtin_bswap128(__val); 41*4824e7fdSDimitry Andric #else 42*4824e7fdSDimitry Andric return static_cast<_Tp>(byteswap(static_cast<uint64_t>(__val))) << 64 | 43*4824e7fdSDimitry Andric static_cast<_Tp>(byteswap(static_cast<uint64_t>(__val >> 64))); 44*4824e7fdSDimitry Andric #endif // __has_builtin(__builtin_bswap128) 45*4824e7fdSDimitry Andric #endif // _LIBCPP_HAS_NO_INT128 46*4824e7fdSDimitry Andric } else { 47*4824e7fdSDimitry Andric static_assert(sizeof(_Tp) == 0, "byteswap is unimplemented for integral types of this size"); 48*4824e7fdSDimitry Andric } 49*4824e7fdSDimitry Andric } 50*4824e7fdSDimitry Andric 51*4824e7fdSDimitry Andric #endif // _LIBCPP_STD_VER > 20 && !defined(_LIBCPP_HAS_NO_CONCEPTS) 52*4824e7fdSDimitry Andric 53*4824e7fdSDimitry Andric _LIBCPP_END_NAMESPACE_STD 54*4824e7fdSDimitry Andric 55*4824e7fdSDimitry Andric #endif // _LIBCPP___BIT_BYTESWAP_H 56