| //===----------------------------------------------------------------------===// |
| // |
| // 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_MAKE_HEAP_H |
| #define _LIBCPP___ALGORITHM_MAKE_HEAP_H |
| |
| #include <__algorithm/comp.h> |
| #include <__algorithm/comp_ref_type.h> |
| #include <__algorithm/iterator_operations.h> |
| #include <__algorithm/push_heap.h> |
| #include <__algorithm/sift_down.h> |
| #include <__config> |
| #include <__iterator/iterator_traits.h> |
| #include <__type_traits/is_arithmetic.h> |
| #include <__utility/move.h> |
| |
| #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 _AlgPolicy, class _Compare, class _RandomAccessIterator> |
| inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void |
| __make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare&& __comp) { |
| __comp_ref_type<_Compare> __comp_ref = __comp; |
| |
| using __diff_t = __iter_diff_t<_RandomAccessIterator>; |
| const __diff_t __n = __last - __first; |
| |
| static const bool __assume_both_children = is_arithmetic<__iter_value_type<_RandomAccessIterator> >::value; |
| |
| // While it would be correct to always assume we have both children, in practice we observed this to be a performance |
| // improvement only for arithmetic types. |
| const __diff_t __sift_down_n = __assume_both_children ? ((__n & 1) ? __n : __n - 1) : __n; |
| |
| if (__n > 1) { |
| // start from the first parent, there is no need to consider children |
| |
| for (__diff_t __start = (__sift_down_n - 2) / 2; __start >= 0; --__start) { |
| std::__sift_down<_AlgPolicy, __assume_both_children>(__first, __comp_ref, __sift_down_n, __start); |
| } |
| if _LIBCPP_CONSTEXPR (__assume_both_children) |
| std::__sift_up<_AlgPolicy>(__first, __last, __comp, __n); |
| } |
| } |
| |
| template <class _RandomAccessIterator, class _Compare> |
| inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void |
| make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) { |
| std::__make_heap<_ClassicAlgPolicy>(std::move(__first), std::move(__last), __comp); |
| } |
| |
| template <class _RandomAccessIterator> |
| inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void |
| make_heap(_RandomAccessIterator __first, _RandomAccessIterator __last) { |
| std::make_heap(std::move(__first), std::move(__last), __less<>()); |
| } |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| _LIBCPP_POP_MACROS |
| |
| #endif // _LIBCPP___ALGORITHM_MAKE_HEAP_H |