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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-exception7//8//===----------------------------------------------------------------------===//9 10#ifndef _LIBCPP___BIT_BIT_CAST_H11#define _LIBCPP___BIT_BIT_CAST_H12 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_header18#endif19 20_LIBCPP_BEGIN_NAMESPACE_STD21 22#ifndef _LIBCPP_CXX03_LANG23 24template <class _ToType, class _FromType>25[[__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_LANG30 31#if _LIBCPP_STD_VER >= 2032 33template <class _ToType, class _FromType>34 requires(sizeof(_ToType) == sizeof(_FromType) && is_trivially_copyable_v<_ToType> &&35 is_trivially_copyable_v<_FromType>)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 >= 2041 42_LIBCPP_END_NAMESPACE_STD43 44#endif // _LIBCPP___BIT_BIT_CAST_H45