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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-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___PSTL_CPU_ALGOS_ANY_OF_H10#define _LIBCPP___PSTL_CPU_ALGOS_ANY_OF_H11 12#include <__algorithm/any_of.h>13#include <__assert>14#include <__atomic/atomic.h>15#include <__atomic/memory_order.h>16#include <__config>17#include <__iterator/concepts.h>18#include <__pstl/backend_fwd.h>19#include <__pstl/cpu_algos/cpu_traits.h>20#include <__type_traits/is_execution_policy.h>21#include <__utility/move.h>22#include <__utility/pair.h>23#include <cstdint>24#include <optional>25 26_LIBCPP_PUSH_MACROS27#include <__undef_macros>28 29#if _LIBCPP_STD_VER >= 1730 31_LIBCPP_BEGIN_NAMESPACE_STD32namespace __pstl {33 34template <class _Backend, class _Index, class _Brick>35_LIBCPP_HIDE_FROM_ABI optional<bool> __parallel_or(_Index __first, _Index __last, _Brick __f) {36 std::atomic<bool> __found(false);37 auto __ret = __cpu_traits<_Backend>::__for_each(__first, __last, [__f, &__found](_Index __i, _Index __j) {38 if (!__found.load(std::memory_order_relaxed) && __f(__i, __j)) {39 __found.store(true, std::memory_order_relaxed);40 __cpu_traits<_Backend>::__cancel_execution();41 }42 });43 if (!__ret)44 return nullopt;45 return static_cast<bool>(__found);46}47 48// TODO: check whether __simd_first() can be used here49template <class _Index, class _DifferenceType, class _Pred>50_LIBCPP_HIDE_FROM_ABI bool __simd_or(_Index __first, _DifferenceType __n, _Pred __pred) noexcept {51 _DifferenceType __block_size = 4 < __n ? 4 : __n;52 const _Index __last = __first + __n;53 while (__last != __first) {54 int32_t __flag = 1;55 _PSTL_PRAGMA_SIMD_REDUCTION(& : __flag)56 for (_DifferenceType __i = 0; __i < __block_size; ++__i)57 if (__pred(*(__first + __i)))58 __flag = 0;59 if (!__flag)60 return true;61 62 __first += __block_size;63 if (__last - __first >= __block_size << 1) {64 // Double the block _Size. Any unnecessary iterations can be amortized against work done so far.65 __block_size <<= 1;66 } else {67 __block_size = __last - __first;68 }69 }70 return false;71}72 73template <class _Backend, class _RawExecutionPolicy>74struct __cpu_parallel_any_of {75 template <class _Policy, class _ForwardIterator, class _Predicate>76 _LIBCPP_HIDE_FROM_ABI optional<bool>77 operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) const noexcept {78 if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy> &&79 __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {80 return __pstl::__parallel_or<_Backend>(81 __first, __last, [&__policy, &__pred](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {82 using _AnyOfUnseq = __pstl::__any_of<_Backend, __remove_parallel_policy_t<_RawExecutionPolicy>>;83 auto __res = _AnyOfUnseq()(std::__remove_parallel_policy(__policy), __brick_first, __brick_last, __pred);84 _LIBCPP_ASSERT_INTERNAL(__res, "unseq/seq should never try to allocate!");85 return *std::move(__res);86 });87 } else if constexpr (__is_unsequenced_execution_policy_v<_RawExecutionPolicy> &&88 __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {89 return __pstl::__simd_or(__first, __last - __first, __pred);90 } else {91 return std::any_of(__first, __last, __pred);92 }93 }94};95 96} // namespace __pstl97_LIBCPP_END_NAMESPACE_STD98 99#endif // _LIBCPP_STD_VER >= 17100 101_LIBCPP_POP_MACROS102 103#endif // _LIBCPP___PSTL_CPU_ALGOS_ANY_OF_H104