1//===----------------------------------------------------------------------===//
 2//
 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 4// See https://llvm.org/LICENSE.txt for license information.
 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 6//
 7//===----------------------------------------------------------------------===//
 8
 9#ifndef _LIBCPP___ALGORITHM_UPPER_BOUND_H
10#define _LIBCPP___ALGORITHM_UPPER_BOUND_H
11
12#include <__algorithm/comp.h>
13#include <__algorithm/half_positive.h>
14#include <__algorithm/iterator_operations.h>
15#include <__config>
16#include <__functional/identity.h>
17#include <__functional/invoke.h>
18#include <__iterator/advance.h>
19#include <__iterator/distance.h>
20#include <__iterator/iterator_traits.h>
21#include <__type_traits/invoke.h>
22#include <__type_traits/is_callable.h>
23#include <__type_traits/is_constructible.h>
24#include <__utility/move.h>
25
26#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
27#  pragma GCC system_header
28#endif
29
30_LIBCPP_PUSH_MACROS
31#include <__undef_macros>
32
33_LIBCPP_BEGIN_NAMESPACE_STD
34
35template <class _AlgPolicy, class _Compare, class _Iter, class _Sent, class _Tp, class _Proj>
36_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Iter
37__upper_bound(_Iter __first, _Sent __last, const _Tp& __value, _Compare&& __comp, _Proj&& __proj) {
38  auto __len = _IterOps<_AlgPolicy>::distance(__first, __last);
39  while (__len != 0) {
40    auto __half_len = std::__half_positive(__len);
41    auto __mid      = _IterOps<_AlgPolicy>::next(__first, __half_len);
42    if (std::__invoke(__comp, __value, std::__invoke(__proj, *__mid)))
43      __len = __half_len;
44    else {
45      __first = ++__mid;
46      __len -= __half_len + 1;
47    }
48  }
49  return __first;
50}
51
52template <class _ForwardIterator, class _Tp, class _Compare>
53[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
54upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value, _Compare __comp) {
55  static_assert(__is_callable<_Compare&, const _Tp&, decltype(*__first)>::value, "The comparator has to be callable");
56  static_assert(is_copy_constructible<_ForwardIterator>::value, "Iterator has to be copy constructible");
57  return std::__upper_bound<_ClassicAlgPolicy>(
58      std::move(__first), std::move(__last), __value, std::move(__comp), std::__identity());
59}
60
61template <class _ForwardIterator, class _Tp>
62[[__nodiscard__]] inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator
63upper_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
64  return std::upper_bound(std::move(__first), std::move(__last), __value, __less<>());
65}
66
67_LIBCPP_END_NAMESPACE_STD
68
69_LIBCPP_POP_MACROS
70
71#endif // _LIBCPP___ALGORITHM_UPPER_BOUND_H