Nikolas Klauser e7e3711885 [libc++][PSTL] Make the PSTL available by default under -fexperimental-library
This removes the need for a custom libc++ build to have a basic set of PSTL algorithms.

Reviewed By: ldionne, #libc

Spies: miyuki, libcxx-commits, arichardson

Differential Revision: https://reviews.llvm.org/D149624
2023-05-05 13:53:17 -07:00

73 lines
2.7 KiB
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_PSTL_FILL_H
#define _LIBCPP___ALGORITHM_PSTL_FILL_H
#include <__algorithm/fill.h>
#include <__config>
#include <__iterator/iterator_traits.h>
#include <__pstl/internal/parallel_impl.h>
#include <__pstl/internal/unseq_backend_simd.h>
#include <__type_traits/is_execution_policy.h>
#include <__type_traits/remove_cvref.h>
#include <__utility/terminate_on_exception.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
_LIBCPP_BEGIN_NAMESPACE_STD
template <class _ExecutionPolicy,
class _ForwardIterator,
class _Tp,
enable_if_t<is_execution_policy_v<__remove_cvref_t<_ExecutionPolicy>>, int> = 0>
_LIBCPP_HIDE_FROM_ABI void
fill(_ExecutionPolicy&& __policy, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
__is_cpp17_random_access_iterator<_ForwardIterator>::value) {
std::__terminate_on_exception([&] {
__pstl::__par_backend::__parallel_for(
__pstl::__internal::__par_backend_tag{},
__policy,
__first,
__last,
[&__policy, &__value](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
std::fill(std::__remove_parallel_policy(__policy), __brick_first, __brick_last, __value);
});
});
} else if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__is_cpp17_random_access_iterator<_ForwardIterator>::value) {
__pstl::__unseq_backend::__simd_fill_n(__first, __last - __first, __value);
} else {
std::fill(__first, __last, __value);
}
}
template <class _ExecutionPolicy,
class _ForwardIterator,
class _SizeT,
class _Tp,
enable_if_t<is_execution_policy_v<__remove_cvref_t<_ExecutionPolicy>>, int> = 0>
_LIBCPP_HIDE_FROM_ABI void
fill_n(_ExecutionPolicy&& __policy, _ForwardIterator __first, _SizeT __n, const _Tp& __value) {
if constexpr (__is_cpp17_random_access_iterator<_ForwardIterator>::value)
std::fill(__policy, __first, __first + __n, __value);
else
std::fill_n(__first, __n, __value);
}
_LIBCPP_END_NAMESPACE_STD
#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
#endif // _LIBCPP___ALGORITHM_PSTL_FILL_H