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
10 #ifndef _LIBCPP___ALGORITHM_EQUAL_H
11 #define _LIBCPP___ALGORITHM_EQUAL_H
12
13 #include <__algorithm/comp.h>
14 #include <__algorithm/unwrap_iter.h>
15 #include <__config>
16 #include <__functional/identity.h>
17 #include <__functional/invoke.h>
18 #include <__iterator/distance.h>
19 #include <__iterator/iterator_traits.h>
20 #include <__string/constexpr_c_functions.h>
21 #include <__type_traits/enable_if.h>
22 #include <__type_traits/integral_constant.h>
23 #include <__type_traits/is_constant_evaluated.h>
24 #include <__type_traits/is_equality_comparable.h>
25 #include <__type_traits/is_volatile.h>
26 #include <__type_traits/predicate_traits.h>
27 #include <__utility/move.h>
28
29 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
30 # pragma GCC system_header
31 #endif
32
33 _LIBCPP_BEGIN_NAMESPACE_STD
34
35 template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
__equal_iter_impl(_InputIterator1 __first1,_InputIterator1 __last1,_InputIterator2 __first2,_BinaryPredicate & __pred)36 _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __equal_iter_impl(
37 _InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate& __pred) {
38 for (; __first1 != __last1; ++__first1, (void)++__first2)
39 if (!__pred(*__first1, *__first2))
40 return false;
41 return true;
42 }
43
44 template <
45 class _Tp,
46 class _Up,
47 class _BinaryPredicate,
48 __enable_if_t<__is_trivial_equality_predicate<_BinaryPredicate, _Tp, _Up>::value && !is_volatile<_Tp>::value &&
49 !is_volatile<_Up>::value && __libcpp_is_trivially_equality_comparable<_Tp, _Up>::value,
50 int> = 0>
51 _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
__equal_iter_impl(_Tp * __first1,_Tp * __last1,_Up * __first2,_BinaryPredicate &)52 __equal_iter_impl(_Tp* __first1, _Tp* __last1, _Up* __first2, _BinaryPredicate&) {
53 return std::__constexpr_memcmp(__first1, __first2, (__last1 - __first1) * sizeof(_Tp)) == 0;
54 }
55
56 template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
57 _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
equal(_InputIterator1 __first1,_InputIterator1 __last1,_InputIterator2 __first2,_BinaryPredicate __pred)58 equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate __pred) {
59 return std::__equal_iter_impl(
60 std::__unwrap_iter(__first1), std::__unwrap_iter(__last1), std::__unwrap_iter(__first2), __pred);
61 }
62
63 template <class _InputIterator1, class _InputIterator2>
64 _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
equal(_InputIterator1 __first1,_InputIterator1 __last1,_InputIterator2 __first2)65 equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2) {
66 return std::equal(__first1, __last1, __first2, __equal_to());
67 }
68
69 #if _LIBCPP_STD_VER >= 14
70 template <class _BinaryPredicate, class _InputIterator1, class _InputIterator2>
71 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
__equal(_InputIterator1 __first1,_InputIterator1 __last1,_InputIterator2 __first2,_InputIterator2 __last2,_BinaryPredicate __pred,input_iterator_tag,input_iterator_tag)72 __equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2,
73 _BinaryPredicate __pred, input_iterator_tag, input_iterator_tag) {
74 for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void)++__first2)
75 if (!__pred(*__first1, *__first2))
76 return false;
77 return __first1 == __last1 && __first2 == __last2;
78 }
79
80 template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
__equal_impl(_Iter1 __first1,_Sent1 __last1,_Iter2 __first2,_Sent2 __last2,_Pred & __comp,_Proj1 & __proj1,_Proj2 & __proj2)81 _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __equal_impl(
82 _Iter1 __first1, _Sent1 __last1, _Iter2 __first2, _Sent2 __last2, _Pred& __comp, _Proj1& __proj1, _Proj2& __proj2) {
83 while (__first1 != __last1 && __first2 != __last2) {
84 if (!std::__invoke(__comp, std::__invoke(__proj1, *__first1), std::__invoke(__proj2, *__first2)))
85 return false;
86 ++__first1;
87 ++__first2;
88 }
89 return __first1 == __last1 && __first2 == __last2;
90 }
91
92 template <class _Tp,
93 class _Up,
94 class _Pred,
95 class _Proj1,
96 class _Proj2,
97 __enable_if_t<__is_trivial_equality_predicate<_Pred, _Tp, _Up>::value && __is_identity<_Proj1>::value &&
98 __is_identity<_Proj2>::value && !is_volatile<_Tp>::value && !is_volatile<_Up>::value &&
99 __libcpp_is_trivially_equality_comparable<_Tp, _Up>::value,
100 int> = 0>
__equal_impl(_Tp * __first1,_Tp * __last1,_Up * __first2,_Up *,_Pred &,_Proj1 &,_Proj2 &)101 _LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __equal_impl(
102 _Tp* __first1, _Tp* __last1, _Up* __first2, _Up*, _Pred&, _Proj1&, _Proj2&) {
103 return std::__constexpr_memcmp(__first1, __first2, (__last1 - __first1) * sizeof(_Tp)) == 0;
104 }
105
106 template <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
107 inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
__equal(_RandomAccessIterator1 __first1,_RandomAccessIterator1 __last1,_RandomAccessIterator2 __first2,_RandomAccessIterator2 __last2,_BinaryPredicate __pred,random_access_iterator_tag,random_access_iterator_tag)108 __equal(_RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1, _RandomAccessIterator2 __first2,
109 _RandomAccessIterator2 __last2, _BinaryPredicate __pred, random_access_iterator_tag,
110 random_access_iterator_tag) {
111 if (_VSTD::distance(__first1, __last1) != _VSTD::distance(__first2, __last2))
112 return false;
113 __identity __proj;
114 return std::__equal_impl(
115 std::__unwrap_iter(__first1),
116 std::__unwrap_iter(__last1),
117 std::__unwrap_iter(__first2),
118 std::__unwrap_iter(__last2),
119 __pred,
120 __proj,
121 __proj);
122 }
123
124 template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
125 _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
equal(_InputIterator1 __first1,_InputIterator1 __last1,_InputIterator2 __first2,_InputIterator2 __last2,_BinaryPredicate __pred)126 equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2,
127 _BinaryPredicate __pred) {
128 return _VSTD::__equal<_BinaryPredicate&>(
129 __first1, __last1, __first2, __last2, __pred, typename iterator_traits<_InputIterator1>::iterator_category(),
130 typename iterator_traits<_InputIterator2>::iterator_category());
131 }
132
133 template <class _InputIterator1, class _InputIterator2>
134 _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
equal(_InputIterator1 __first1,_InputIterator1 __last1,_InputIterator2 __first2,_InputIterator2 __last2)135 equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2) {
136 return std::__equal(
137 __first1,
138 __last1,
139 __first2,
140 __last2,
141 __equal_to(),
142 typename iterator_traits<_InputIterator1>::iterator_category(),
143 typename iterator_traits<_InputIterator2>::iterator_category());
144 }
145 #endif
146
147 _LIBCPP_END_NAMESPACE_STD
148
149 #endif // _LIBCPP___ALGORITHM_EQUAL_H
150