bit_cast.h 1.1 KB

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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-exception
  7. //
  8. //===----------------------------------------------------------------------===//
  9. #ifndef _LIBCPP___BIT_BIT_CAST_H
  10. #define _LIBCPP___BIT_BIT_CAST_H
  11. #include <__config>
  12. #include <__type_traits/is_trivially_copyable.h>
  13. #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  14. # pragma GCC system_header
  15. #endif
  16. _LIBCPP_BEGIN_NAMESPACE_STD
  17. #if _LIBCPP_STD_VER >= 20
  18. template <class _ToType, class _FromType>
  19. requires(sizeof(_ToType) == sizeof(_FromType) &&
  20. is_trivially_copyable_v<_ToType> &&
  21. is_trivially_copyable_v<_FromType>)
  22. _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr _ToType bit_cast(const _FromType& __from) noexcept {
  23. return __builtin_bit_cast(_ToType, __from);
  24. }
  25. #endif // _LIBCPP_STD_VER >= 20
  26. _LIBCPP_END_NAMESPACE_STD
  27. #endif // _LIBCPP___BIT_BIT_CAST_H