1 // -*- C++ -*- 2 //===----------------------------------------------------------------------===// 3 // 4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5 // See https://llvm.org/LICENSE.txt for license information. 6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7 // 8 //===----------------------------------------------------------------------===// 9 10 #ifndef _LIBCPP___BIT_BIT_CAST_H 11 #define _LIBCPP___BIT_BIT_CAST_H 12 13 #include <__config> 14 #include <__type_traits/is_trivially_copyable.h> 15 16 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 17 # pragma GCC system_header 18 #endif 19 20 _LIBCPP_BEGIN_NAMESPACE_STD 21 22 #ifndef _LIBCPP_CXX03_LANG 23 24 template <class _ToType, class _FromType> __bit_cast(const _FromType & __from)25_LIBCPP_NODISCARD _LIBCPP_HIDE_FROM_ABI constexpr _ToType __bit_cast(const _FromType& __from) noexcept { 26 return __builtin_bit_cast(_ToType, __from); 27 } 28 29 #endif // _LIBCPP_CXX03_LANG 30 31 #if _LIBCPP_STD_VER >= 20 32 33 template <class _ToType, class _FromType> 34 requires(sizeof(_ToType) == sizeof(_FromType) && is_trivially_copyable_v<_ToType> && 35 is_trivially_copyable_v<_FromType>) bit_cast(const _FromType & __from)36[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _ToType bit_cast(const _FromType& __from) noexcept { 37 return __builtin_bit_cast(_ToType, __from); 38 } 39 40 #endif // _LIBCPP_STD_VER >= 20 41 42 _LIBCPP_END_NAMESPACE_STD 43 44 #endif // _LIBCPP___BIT_BIT_CAST_H 45