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/operation_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_PUSH_MACROS
34#include <__undef_macros>
35
36_LIBCPP_BEGIN_NAMESPACE_STD
37
38template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
39_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __equal_iter_impl(
40    _InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate& __pred) {
41  for (; __first1 != __last1; ++__first1, (void)++__first2)
42    if (!__pred(*__first1, *__first2))
43      return false;
44  return true;
45}
46
47template <class _Tp,
48          class _Up,
49          class _BinaryPredicate,
50          __enable_if_t<__desugars_to<__equal_tag, _BinaryPredicate, _Tp, _Up>::value && !is_volatile<_Tp>::value &&
51                            !is_volatile<_Up>::value && __libcpp_is_trivially_equality_comparable<_Tp, _Up>::value,
52                        int> = 0>
53_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
54__equal_iter_impl(_Tp* __first1, _Tp* __last1, _Up* __first2, _BinaryPredicate&) {
55  return std::__constexpr_memcmp_equal(__first1, __first2, __element_count(__last1 - __first1));
56}
57
58template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
59_LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
60equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate __pred) {
61  return std::__equal_iter_impl(
62      std::__unwrap_iter(__first1), std::__unwrap_iter(__last1), std::__unwrap_iter(__first2), __pred);
63}
64
65template <class _InputIterator1, class _InputIterator2>
66_LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
67equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2) {
68  return std::equal(__first1, __last1, __first2, __equal_to());
69}
70
71#if _LIBCPP_STD_VER >= 14
72template <class _BinaryPredicate, class _InputIterator1, class _InputIterator2>
73inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
74__equal(_InputIterator1 __first1,
75        _InputIterator1 __last1,
76        _InputIterator2 __first2,
77        _InputIterator2 __last2,
78        _BinaryPredicate __pred,
79        input_iterator_tag,
80        input_iterator_tag) {
81  for (; __first1 != __last1 && __first2 != __last2; ++__first1, (void)++__first2)
82    if (!__pred(*__first1, *__first2))
83      return false;
84  return __first1 == __last1 && __first2 == __last2;
85}
86
87template <class _Iter1, class _Sent1, class _Iter2, class _Sent2, class _Pred, class _Proj1, class _Proj2>
88_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __equal_impl(
89    _Iter1 __first1, _Sent1 __last1, _Iter2 __first2, _Sent2 __last2, _Pred& __comp, _Proj1& __proj1, _Proj2& __proj2) {
90  while (__first1 != __last1 && __first2 != __last2) {
91    if (!std::__invoke(__comp, std::__invoke(__proj1, *__first1), std::__invoke(__proj2, *__first2)))
92      return false;
93    ++__first1;
94    ++__first2;
95  }
96  return __first1 == __last1 && __first2 == __last2;
97}
98
99template <class _Tp,
100          class _Up,
101          class _Pred,
102          class _Proj1,
103          class _Proj2,
104          __enable_if_t<__desugars_to<__equal_tag, _Pred, _Tp, _Up>::value && __is_identity<_Proj1>::value &&
105                            __is_identity<_Proj2>::value && !is_volatile<_Tp>::value && !is_volatile<_Up>::value &&
106                            __libcpp_is_trivially_equality_comparable<_Tp, _Up>::value,
107                        int> = 0>
108_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
109__equal_impl(_Tp* __first1, _Tp* __last1, _Up* __first2, _Up*, _Pred&, _Proj1&, _Proj2&) {
110  return std::__constexpr_memcmp_equal(__first1, __first2, __element_count(__last1 - __first1));
111}
112
113template <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
114inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
115__equal(_RandomAccessIterator1 __first1,
116        _RandomAccessIterator1 __last1,
117        _RandomAccessIterator2 __first2,
118        _RandomAccessIterator2 __last2,
119        _BinaryPredicate __pred,
120        random_access_iterator_tag,
121        random_access_iterator_tag) {
122  if (std::distance(__first1, __last1) != std::distance(__first2, __last2))
123    return false;
124  __identity __proj;
125  return std::__equal_impl(
126      std::__unwrap_iter(__first1),
127      std::__unwrap_iter(__last1),
128      std::__unwrap_iter(__first2),
129      std::__unwrap_iter(__last2),
130      __pred,
131      __proj,
132      __proj);
133}
134
135template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
136_LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
137equal(_InputIterator1 __first1,
138      _InputIterator1 __last1,
139      _InputIterator2 __first2,
140      _InputIterator2 __last2,
141      _BinaryPredicate __pred) {
142  return std::__equal<_BinaryPredicate&>(
143      __first1,
144      __last1,
145      __first2,
146      __last2,
147      __pred,
148      typename iterator_traits<_InputIterator1>::iterator_category(),
149      typename iterator_traits<_InputIterator2>::iterator_category());
150}
151
152template <class _InputIterator1, class _InputIterator2>
153_LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
154equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _InputIterator2 __last2) {
155  return std::__equal(
156      __first1,
157      __last1,
158      __first2,
159      __last2,
160      __equal_to(),
161      typename iterator_traits<_InputIterator1>::iterator_category(),
162      typename iterator_traits<_InputIterator2>::iterator_category());
163}
164#endif
165
166_LIBCPP_END_NAMESPACE_STD
167
168_LIBCPP_POP_MACROS
169
170#endif // _LIBCPP___ALGORITHM_EQUAL_H
171