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//===----------------------------------------------------------------------===//
//
// 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___CXX03___PSTL_CPU_ALGOS_ANY_OF_H
#define _LIBCPP___CXX03___PSTL_CPU_ALGOS_ANY_OF_H
#include <__cxx03/__algorithm/any_of.h>
#include <__cxx03/__assert>
#include <__cxx03/__atomic/atomic.h>
#include <__cxx03/__atomic/memory_order.h>
#include <__cxx03/__config>
#include <__cxx03/__iterator/concepts.h>
#include <__cxx03/__pstl/backend_fwd.h>
#include <__cxx03/__pstl/cpu_algos/cpu_traits.h>
#include <__cxx03/__type_traits/is_execution_policy.h>
#include <__cxx03/__utility/move.h>
#include <__cxx03/__utility/pair.h>
#include <__cxx03/cstdint>
#include <__cxx03/optional>
_LIBCPP_PUSH_MACROS
#include <__cxx03/__undef_macros>
_LIBCPP_BEGIN_NAMESPACE_STD
namespace __pstl {
template <class _Backend, class _Index, class _Brick>
_LIBCPP_HIDE_FROM_ABI optional<bool> __parallel_or(_Index __first, _Index __last, _Brick __f) {
std::atomic<bool> __found(false);
auto __ret = __cpu_traits<_Backend>::__for_each(__first, __last, [__f, &__found](_Index __i, _Index __j) {
if (!__found.load(std::memory_order_relaxed) && __f(__i, __j)) {
__found.store(true, std::memory_order_relaxed);
__cpu_traits<_Backend>::__cancel_execution();
}
});
if (!__ret)
return nullopt;
return static_cast<bool>(__found);
}
// TODO: check whether __simd_first() can be used here
template <class _Index, class _DifferenceType, class _Pred>
_LIBCPP_HIDE_FROM_ABI bool __simd_or(_Index __first, _DifferenceType __n, _Pred __pred) noexcept {
_DifferenceType __block_size = 4 < __n ? 4 : __n;
const _Index __last = __first + __n;
while (__last != __first) {
int32_t __flag = 1;
_PSTL_PRAGMA_SIMD_REDUCTION(& : __flag)
for (_DifferenceType __i = 0; __i < __block_size; ++__i)
if (__pred(*(__first + __i)))
__flag = 0;
if (!__flag)
return true;
__first += __block_size;
if (__last - __first >= __block_size << 1) {
// Double the block _Size. Any unnecessary iterations can be amortized against work done so far.
__block_size <<= 1;
} else {
__block_size = __last - __first;
}
}
return false;
}
template <class _Backend, class _RawExecutionPolicy>
struct __cpu_parallel_any_of {
template <class _Policy, class _ForwardIterator, class _Predicate>
_LIBCPP_HIDE_FROM_ABI optional<bool>
operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) const noexcept {
if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
return __pstl::__parallel_or<_Backend>(
__first, __last, [&__policy, &__pred](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
using _AnyOfUnseq = __pstl::__any_of<_Backend, __remove_parallel_policy_t<_RawExecutionPolicy>>;
auto __res = _AnyOfUnseq()(std::__remove_parallel_policy(__policy), __brick_first, __brick_last, __pred);
_LIBCPP_ASSERT_INTERNAL(__res, "unseq/seq should never try to allocate!");
return *std::move(__res);
});
} else if constexpr (__is_unsequenced_execution_policy_v<_RawExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
return __pstl::__simd_or(__first, __last - __first, __pred);
} else {
return std::any_of(__first, __last, __pred);
}
}
};
} // namespace __pstl
_LIBCPP_END_NAMESPACE_STD
_LIBCPP_POP_MACROS
#endif // _LIBCPP___CXX03___PSTL_CPU_ALGOS_ANY_OF_H
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