2d106844e7
Part of https://github.com/llvm/llvm-project/issues/102817. This patch attempts to optimize the performance of `ranges::fold_left_with_iter` for segmented iterators. - before ``` # | rng::fold_left(vector<int>)/8 2.78 ns 2.78 ns 241953718 # | rng::fold_left(vector<int>)/32 12.2 ns 12.2 ns 57579851 # | rng::fold_left(vector<int>)/50 19.2 ns 19.2 ns 36487764 # | rng::fold_left(vector<int>)/8192 3226 ns 3226 ns 216811 # | rng::fold_left(vector<int>)/1048576 441842 ns 441839 ns 1592 # | rng::fold_left(deque<int>)/8 2.83 ns 2.83 ns 243888678 # | rng::fold_left(deque<int>)/32 16.6 ns 16.6 ns 42297458 # | rng::fold_left(deque<int>)/50 22.3 ns 22.3 ns 31387998 # | rng::fold_left(deque<int>)/8192 2492 ns 2492 ns 281637 # | rng::fold_left(deque<int>)/1048576 324936 ns 324936 ns 2154 # | rng::fold_left(list<int>)/8 2.54 ns 2.54 ns 275946635 # | rng::fold_left(list<int>)/32 16.2 ns 16.2 ns 42901634 # | rng::fold_left(list<int>)/50 54.7 ns 54.7 ns 12767450 # | rng::fold_left(list<int>)/8192 15154 ns 15154 ns 56744 # | rng::fold_left(list<int>)/1048576 4976906 ns 4976867 ns 158 ``` - after ``` # | rng::fold_left(vector<int>)/8 2.74 ns 2.74 ns 255954900 # | rng::fold_left(vector<int>)/32 12.1 ns 12.1 ns 57843462 # | rng::fold_left(vector<int>)/50 19.2 ns 19.2 ns 36422594 # | rng::fold_left(vector<int>)/8192 3202 ns 3202 ns 218265 # | rng::fold_left(vector<int>)/1048576 435718 ns 435709 ns 1609 # | rng::fold_left(deque<int>)/8 2.52 ns 2.52 ns 277288254 # | rng::fold_left(deque<int>)/32 14.1 ns 14.1 ns 52244463 # | rng::fold_left(deque<int>)/50 16.2 ns 16.2 ns 43131857 # | rng::fold_left(deque<int>)/8192 1695 ns 1695 ns 415620 # | rng::fold_left(deque<int>)/1048576 277729 ns 277731 ns 2532 # | rng::fold_left(list<int>)/8 2.55 ns 2.55 ns 277025050 # | rng::fold_left(list<int>)/32 16.2 ns 16.2 ns 43058857 # | rng::fold_left(list<int>)/50 54.7 ns 54.7 ns 12705516 # | rng::fold_left(list<int>)/8192 15236 ns 15235 ns 56840 # | rng::fold_left(list<int>)/1048576 4827263 ns 4827147 ns 152 ```
138 lines
5.1 KiB
C++
138 lines
5.1 KiB
C++
// -*- C++ -*-
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// 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_RANGES_FOLD_H
|
|
#define _LIBCPP___ALGORITHM_RANGES_FOLD_H
|
|
|
|
#include <__algorithm/for_each.h>
|
|
#include <__concepts/assignable.h>
|
|
#include <__concepts/constructible.h>
|
|
#include <__concepts/convertible_to.h>
|
|
#include <__concepts/invocable.h>
|
|
#include <__concepts/movable.h>
|
|
#include <__config>
|
|
#include <__functional/identity.h>
|
|
#include <__functional/invoke.h>
|
|
#include <__functional/reference_wrapper.h>
|
|
#include <__iterator/concepts.h>
|
|
#include <__iterator/iterator_traits.h>
|
|
#include <__iterator/next.h>
|
|
#include <__ranges/access.h>
|
|
#include <__ranges/concepts.h>
|
|
#include <__ranges/dangling.h>
|
|
#include <__type_traits/decay.h>
|
|
#include <__type_traits/invoke.h>
|
|
#include <__utility/forward.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
|
|
|
|
#if _LIBCPP_STD_VER >= 23
|
|
|
|
namespace ranges {
|
|
template <class _Ip, class _Tp>
|
|
struct in_value_result {
|
|
_LIBCPP_NO_UNIQUE_ADDRESS _Ip in;
|
|
_LIBCPP_NO_UNIQUE_ADDRESS _Tp value;
|
|
|
|
template <class _I2, class _T2>
|
|
requires convertible_to<const _Ip&, _I2> && convertible_to<const _Tp&, _T2>
|
|
_LIBCPP_HIDE_FROM_ABI constexpr operator in_value_result<_I2, _T2>() const& {
|
|
return {in, value};
|
|
}
|
|
|
|
template <class _I2, class _T2>
|
|
requires convertible_to<_Ip, _I2> && convertible_to<_Tp, _T2>
|
|
_LIBCPP_HIDE_FROM_ABI constexpr operator in_value_result<_I2, _T2>() && {
|
|
return {std::move(in), std::move(value)};
|
|
}
|
|
};
|
|
|
|
template <class _Ip, class _Tp>
|
|
using fold_left_with_iter_result = in_value_result<_Ip, _Tp>;
|
|
|
|
template <class _Fp, class _Tp, class _Ip, class _Rp, class _Up = decay_t<_Rp>>
|
|
concept __indirectly_binary_left_foldable_impl =
|
|
convertible_to<_Rp, _Up> && //
|
|
movable<_Tp> && //
|
|
movable<_Up> && //
|
|
convertible_to<_Tp, _Up> && //
|
|
invocable<_Fp&, _Up, iter_reference_t<_Ip>> && //
|
|
assignable_from<_Up&, invoke_result_t<_Fp&, _Up, iter_reference_t<_Ip>>>;
|
|
|
|
template <class _Fp, class _Tp, class _Ip>
|
|
concept __indirectly_binary_left_foldable =
|
|
copy_constructible<_Fp> && //
|
|
invocable<_Fp&, _Tp, iter_reference_t<_Ip>> && //
|
|
__indirectly_binary_left_foldable_impl<_Fp, _Tp, _Ip, invoke_result_t<_Fp&, _Tp, iter_reference_t<_Ip>>>;
|
|
|
|
struct __fold_left_with_iter {
|
|
template <input_iterator _Ip, sentinel_for<_Ip> _Sp, class _Tp, __indirectly_binary_left_foldable<_Tp, _Ip> _Fp>
|
|
[[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto operator()(_Ip __first, _Sp __last, _Tp __init, _Fp __f) {
|
|
using _Up = decay_t<invoke_result_t<_Fp&, _Tp, iter_reference_t<_Ip>>>;
|
|
|
|
if (__first == __last) {
|
|
return fold_left_with_iter_result<_Ip, _Up>{std::move(__first), _Up(std::move(__init))};
|
|
}
|
|
|
|
_Up __result = std::invoke(__f, std::move(__init), *__first);
|
|
++__first;
|
|
__identity __proj;
|
|
auto __end = std::__for_each(
|
|
std::move(__first),
|
|
std::move(__last),
|
|
[&](auto&& __element) {
|
|
__result = std::invoke(__f, std::move(__result), std::forward<decltype(__element)>(__element));
|
|
},
|
|
__proj);
|
|
|
|
return fold_left_with_iter_result<_Ip, _Up>{std::move(__end), std::move(__result)};
|
|
}
|
|
|
|
template <input_range _Rp, class _Tp, __indirectly_binary_left_foldable<_Tp, iterator_t<_Rp>> _Fp>
|
|
[[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto operator()(_Rp&& __r, _Tp __init, _Fp __f) {
|
|
auto __result = operator()(ranges::begin(__r), ranges::end(__r), std::move(__init), std::ref(__f));
|
|
|
|
using _Up = decay_t<invoke_result_t<_Fp&, _Tp, range_reference_t<_Rp>>>;
|
|
return fold_left_with_iter_result<borrowed_iterator_t<_Rp>, _Up>{std::move(__result.in), std::move(__result.value)};
|
|
}
|
|
};
|
|
|
|
inline constexpr auto fold_left_with_iter = __fold_left_with_iter();
|
|
|
|
struct __fold_left {
|
|
template <input_iterator _Ip, sentinel_for<_Ip> _Sp, class _Tp, __indirectly_binary_left_foldable<_Tp, _Ip> _Fp>
|
|
[[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto operator()(_Ip __first, _Sp __last, _Tp __init, _Fp __f) {
|
|
return fold_left_with_iter(std::move(__first), std::move(__last), std::move(__init), std::ref(__f)).value;
|
|
}
|
|
|
|
template <input_range _Rp, class _Tp, __indirectly_binary_left_foldable<_Tp, iterator_t<_Rp>> _Fp>
|
|
[[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto operator()(_Rp&& __r, _Tp __init, _Fp __f) {
|
|
return fold_left_with_iter(ranges::begin(__r), ranges::end(__r), std::move(__init), std::ref(__f)).value;
|
|
}
|
|
};
|
|
|
|
inline constexpr auto fold_left = __fold_left();
|
|
} // namespace ranges
|
|
|
|
#endif // _LIBCPP_STD_VER >= 23
|
|
|
|
_LIBCPP_END_NAMESPACE_STD
|
|
|
|
_LIBCPP_POP_MACROS
|
|
|
|
#endif // _LIBCPP___ALGORITHM_RANGES_FOLD_H
|