v1/__memory/destruct_n.h

0001 //===----------------------------------------------------------------------===//
0002 //
0003 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0004 // See https://llvm.org/LICENSE.txt for license information.
0005 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0006 //
0007 //===----------------------------------------------------------------------===//
0008
0009 #ifndef _LIBCPP___MEMORY_DESTRUCT_N_H
0010 #define _LIBCPP___MEMORY_DESTRUCT_N_H
0011
0012 #include <__config>
0013 #include <__cstddef/size_t.h>
0014 #include <__type_traits/integral_constant.h>
0015 #include <__type_traits/is_trivially_destructible.h>
0016
0017 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
0018 #  pragma GCC system_header
0019 #endif
0020
0021 _LIBCPP_BEGIN_NAMESPACE_STD
0022
0023 struct __destruct_n {
0024 private:
0025   size_t __size_;
0026
0027   template <class _Tp>
0028   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX26 void __process(_Tp* __p, false_type) _NOEXCEPT {
0029     for (size_t __i = 0; __i < __size_; ++__i, ++__p)
0030       __p->~_Tp();
0031   }
0032
0033   template <class _Tp>
0034   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX26 void __process(_Tp*, true_type) _NOEXCEPT {}
0035
0036   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX26 void __incr(false_type) _NOEXCEPT { ++__size_; }
0037   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX26 void __incr(true_type) _NOEXCEPT {}
0038
0039   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX26 void __set(size_t __s, false_type) _NOEXCEPT { __size_ = __s; }
0040   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX26 void __set(size_t, true_type) _NOEXCEPT {}
0041
0042 public:
0043   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX26 explicit __destruct_n(size_t __s) _NOEXCEPT : __size_(__s) {}
0044
0045   template <class _Tp>
0046   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX26 void __incr() _NOEXCEPT {
0047     __incr(integral_constant<bool, is_trivially_destructible<_Tp>::value>());
0048   }
0049
0050   template <class _Tp>
0051   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX26 void __set(size_t __s, _Tp*) _NOEXCEPT {
0052     __set(__s, integral_constant<bool, is_trivially_destructible<_Tp>::value>());
0053   }
0054
0055   template <class _Tp>
0056   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX26 void operator()(_Tp* __p) _NOEXCEPT {
0057     __process(__p, integral_constant<bool, is_trivially_destructible<_Tp>::value>());
0058   }
0059 };
0060
0061 _LIBCPP_END_NAMESPACE_STD
0062
0063 #endif // _LIBCPP___MEMORY_DESTRUCT_N_H