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Diffstat (limited to 'contrib/llvm-project/libcxx/include/__algorithm/lower_bound.h')
-rw-r--r-- | contrib/llvm-project/libcxx/include/__algorithm/lower_bound.h | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/contrib/llvm-project/libcxx/include/__algorithm/lower_bound.h b/contrib/llvm-project/libcxx/include/__algorithm/lower_bound.h new file mode 100644 index 000000000000..1448c8963327 --- /dev/null +++ b/contrib/llvm-project/libcxx/include/__algorithm/lower_bound.h @@ -0,0 +1,72 @@ +//===----------------------------------------------------------------------===// +// +// 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___ALGORITHM_LOWER_BOUND_H +#define _LIBCPP___ALGORITHM_LOWER_BOUND_H + +#include <__config> +#include <__algorithm/comp.h> +#include <__algorithm/half_positive.h> +#include <iterator> + +#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) +#pragma GCC system_header +#endif + +_LIBCPP_PUSH_MACROS +#include <__undef_macros> + +_LIBCPP_BEGIN_NAMESPACE_STD + +template <class _Compare, class _ForwardIterator, class _Tp> +_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator +__lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp) +{ + typedef typename iterator_traits<_ForwardIterator>::difference_type difference_type; + difference_type __len = _VSTD::distance(__first, __last); + while (__len != 0) + { + difference_type __l2 = _VSTD::__half_positive(__len); + _ForwardIterator __m = __first; + _VSTD::advance(__m, __l2); + if (__comp(*__m, __value_)) + { + __first = ++__m; + __len -= __l2 + 1; + } + else + __len = __l2; + } + return __first; +} + +template <class _ForwardIterator, class _Tp, class _Compare> +_LIBCPP_NODISCARD_EXT inline +_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 +_ForwardIterator +lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_, _Compare __comp) +{ + typedef typename add_lvalue_reference<_Compare>::type _Comp_ref; + return _VSTD::__lower_bound<_Comp_ref>(__first, __last, __value_, __comp); +} + +template <class _ForwardIterator, class _Tp> +_LIBCPP_NODISCARD_EXT inline +_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 +_ForwardIterator +lower_bound(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value_) +{ + return _VSTD::lower_bound(__first, __last, __value_, + __less<typename iterator_traits<_ForwardIterator>::value_type, _Tp>()); +} + +_LIBCPP_END_NAMESPACE_STD + +_LIBCPP_POP_MACROS + +#endif // _LIBCPP___ALGORITHM_LOWER_BOUND_H |