1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
|
// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___MEMORY_COMPRESSED_PAIR_H
#define _LIBCPP___MEMORY_COMPRESSED_PAIR_H
#include <__config>
#include <__utility/forward.h>
#include <__utility/move.h>
#include <tuple> // needed in c++03 for some constructors
#include <type_traits>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
// Tag used to default initialize one or both of the pair's elements.
struct __default_init_tag {};
struct __value_init_tag {};
template <class _Tp, int _Idx, bool _CanBeEmptyBase = is_empty<_Tp>::value && !__libcpp_is_final<_Tp>::value>
struct __compressed_pair_elem {
using _ParamT = _Tp;
using reference = _Tp&;
using const_reference = const _Tp&;
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __compressed_pair_elem(__default_init_tag) {}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __compressed_pair_elem(__value_init_tag) : __value_() {}
template <class _Up, class = __enable_if_t<!is_same<__compressed_pair_elem, typename decay<_Up>::type>::value> >
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit
__compressed_pair_elem(_Up&& __u) : __value_(std::forward<_Up>(__u)) {}
#ifndef _LIBCPP_CXX03_LANG
template <class... _Args, size_t... _Indices>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX14
__compressed_pair_elem(piecewise_construct_t, tuple<_Args...> __args, __tuple_indices<_Indices...>)
: __value_(std::forward<_Args>(std::get<_Indices>(__args))...) {}
#endif
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 reference __get() _NOEXCEPT { return __value_; }
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR const_reference __get() const _NOEXCEPT { return __value_; }
private:
_Tp __value_;
};
template <class _Tp, int _Idx>
struct __compressed_pair_elem<_Tp, _Idx, true> : private _Tp {
using _ParamT = _Tp;
using reference = _Tp&;
using const_reference = const _Tp&;
using __value_type = _Tp;
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __compressed_pair_elem() = default;
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __compressed_pair_elem(__default_init_tag) {}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR __compressed_pair_elem(__value_init_tag) : __value_type() {}
template <class _Up, class = __enable_if_t<!is_same<__compressed_pair_elem, typename decay<_Up>::type>::value> >
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
explicit __compressed_pair_elem(_Up&& __u) : __value_type(std::forward<_Up>(__u)) {}
#ifndef _LIBCPP_CXX03_LANG
template <class... _Args, size_t... _Indices>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX14
__compressed_pair_elem(piecewise_construct_t, tuple<_Args...> __args, __tuple_indices<_Indices...>)
: __value_type(std::forward<_Args>(std::get<_Indices>(__args))...) {}
#endif
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11 reference __get() _NOEXCEPT { return *this; }
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR const_reference __get() const _NOEXCEPT { return *this; }
};
template <class _T1, class _T2>
class __compressed_pair : private __compressed_pair_elem<_T1, 0>,
private __compressed_pair_elem<_T2, 1> {
public:
// NOTE: This static assert should never fire because __compressed_pair
// is *almost never* used in a scenario where it's possible for T1 == T2.
// (The exception is std::function where it is possible that the function
// object and the allocator have the same type).
static_assert((!is_same<_T1, _T2>::value),
"__compressed_pair cannot be instantiated when T1 and T2 are the same type; "
"The current implementation is NOT ABI-compatible with the previous implementation for this configuration");
using _Base1 _LIBCPP_NODEBUG = __compressed_pair_elem<_T1, 0>;
using _Base2 _LIBCPP_NODEBUG = __compressed_pair_elem<_T2, 1>;
template <bool _Dummy = true,
class = __enable_if_t<
__dependent_type<is_default_constructible<_T1>, _Dummy>::value &&
__dependent_type<is_default_constructible<_T2>, _Dummy>::value
>
>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
__compressed_pair() : _Base1(__value_init_tag()), _Base2(__value_init_tag()) {}
template <class _U1, class _U2>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
__compressed_pair(_U1&& __t1, _U2&& __t2) : _Base1(std::forward<_U1>(__t1)), _Base2(std::forward<_U2>(__t2)) {}
#ifndef _LIBCPP_CXX03_LANG
template <class... _Args1, class... _Args2>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX14
__compressed_pair(piecewise_construct_t __pc, tuple<_Args1...> __first_args,
tuple<_Args2...> __second_args)
: _Base1(__pc, std::move(__first_args), typename __make_tuple_indices<sizeof...(_Args1)>::type()),
_Base2(__pc, std::move(__second_args), typename __make_tuple_indices<sizeof...(_Args2)>::type()) {}
#endif
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
typename _Base1::reference first() _NOEXCEPT {
return static_cast<_Base1&>(*this).__get();
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
typename _Base1::const_reference first() const _NOEXCEPT {
return static_cast<_Base1 const&>(*this).__get();
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
typename _Base2::reference second() _NOEXCEPT {
return static_cast<_Base2&>(*this).__get();
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR
typename _Base2::const_reference second() const _NOEXCEPT {
return static_cast<_Base2 const&>(*this).__get();
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR static
_Base1* __get_first_base(__compressed_pair* __pair) _NOEXCEPT {
return static_cast<_Base1*>(__pair);
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR static
_Base2* __get_second_base(__compressed_pair* __pair) _NOEXCEPT {
return static_cast<_Base2*>(__pair);
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
void swap(__compressed_pair& __x)
_NOEXCEPT_(__is_nothrow_swappable<_T1>::value && __is_nothrow_swappable<_T2>::value) {
using std::swap;
swap(first(), __x.first());
swap(second(), __x.second());
}
};
template <class _T1, class _T2>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX11
void swap(__compressed_pair<_T1, _T2>& __x, __compressed_pair<_T1, _T2>& __y)
_NOEXCEPT_(__is_nothrow_swappable<_T1>::value && __is_nothrow_swappable<_T2>::value) {
__x.swap(__y);
}
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___MEMORY_COMPRESSED_PAIR_H
|
