v1/__memory/addressof.h

0001 // -*- C++ -*-
0002 //===----------------------------------------------------------------------===//
0003 //
0004 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0005 // See https://llvm.org/LICENSE.txt for license information.
0006 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0007 //
0008 //===----------------------------------------------------------------------===//
0009
0010 #ifndef _LIBCPP___MEMORY_ADDRESSOF_H
0011 #define _LIBCPP___MEMORY_ADDRESSOF_H
0012
0013 #include <__config>
0014
0015 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
0016 #  pragma GCC system_header
0017 #endif
0018
0019 _LIBCPP_BEGIN_NAMESPACE_STD
0020
0021 template <class _Tp>
0022 inline _LIBCPP_CONSTEXPR_SINCE_CXX17 _LIBCPP_NO_CFI _LIBCPP_HIDE_FROM_ABI _Tp* addressof(_Tp& __x) _NOEXCEPT {
0023   return __builtin_addressof(__x);
0024 }
0025
0026 #if _LIBCPP_HAS_OBJC_ARC
0027 // Objective-C++ Automatic Reference Counting uses qualified pointers
0028 // that require special addressof() signatures.
0029 template <class _Tp>
0030 inline _LIBCPP_HIDE_FROM_ABI __strong _Tp* addressof(__strong _Tp& __x) _NOEXCEPT {
0031   return &__x;
0032 }
0033
0034 #  if _LIBCPP_HAS_OBJC_ARC_WEAK
0035 template <class _Tp>
0036 inline _LIBCPP_HIDE_FROM_ABI __weak _Tp* addressof(__weak _Tp& __x) _NOEXCEPT {
0037   return &__x;
0038 }
0039 #  endif
0040
0041 template <class _Tp>
0042 inline _LIBCPP_HIDE_FROM_ABI __autoreleasing _Tp* addressof(__autoreleasing _Tp& __x) _NOEXCEPT {
0043   return &__x;
0044 }
0045
0046 template <class _Tp>
0047 inline _LIBCPP_HIDE_FROM_ABI __unsafe_unretained _Tp* addressof(__unsafe_unretained _Tp& __x) _NOEXCEPT {
0048   return &__x;
0049 }
0050 #endif
0051
0052 #if !defined(_LIBCPP_CXX03_LANG)
0053 template <class _Tp>
0054 _Tp* addressof(const _Tp&&) noexcept = delete;
0055 #endif
0056
0057 _LIBCPP_END_NAMESPACE_STD
0058
0059 #endif // _LIBCPP___MEMORY_ADDRESSOF_H