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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef _LIBCPP___PSTL_CPU_ALGOS_FILL_H 10 #define _LIBCPP___PSTL_CPU_ALGOS_FILL_H 11 12 #include <__algorithm/fill.h> 13 #include <__assert> 14 #include <__config> 15 #include <__iterator/concepts.h> 16 #include <__pstl/backend_fwd.h> 17 #include <__pstl/cpu_algos/cpu_traits.h> 18 #include <__type_traits/is_execution_policy.h> 19 #include <__utility/empty.h> 20 #include <optional> 21 22 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 23 # pragma GCC system_header 24 #endif 25 26 _LIBCPP_BEGIN_NAMESPACE_STD 27 namespace __pstl { 28 29 template <class _Index, class _DifferenceType, class _Tp> 30 _LIBCPP_HIDE_FROM_ABI _Index __simd_fill_n(_Index __first, _DifferenceType __n, const _Tp& __value) noexcept { 31 _PSTL_USE_NONTEMPORAL_STORES_IF_ALLOWED 32 _PSTL_PRAGMA_SIMD 33 for (_DifferenceType __i = 0; __i < __n; ++__i) 34 __first[__i] = __value; 35 return __first + __n; 36 } 37 38 template <class _Backend, class _RawExecutionPolicy> 39 struct __cpu_parallel_fill { 40 template <class _Policy, class _ForwardIterator, class _Tp> 41 _LIBCPP_HIDE_FROM_ABI optional<__empty> 42 operator()(_Policy&& __policy, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) const noexcept { 43 if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy> && 44 __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) { 45 return __cpu_traits<_Backend>::__for_each( 46 __first, __last, [&__policy, &__value](_ForwardIterator __brick_first, _ForwardIterator __brick_last) { 47 using _FillUnseq = __pstl::__fill<_Backend, __remove_parallel_policy_t<_RawExecutionPolicy>>; 48 [[maybe_unused]] auto __res = 49 _FillUnseq()(std::__remove_parallel_policy(__policy), __brick_first, __brick_last, __value); 50 _LIBCPP_ASSERT_INTERNAL(__res, "unseq/seq should never try to allocate!"); 51 }); 52 } else if constexpr (__is_unsequenced_execution_policy_v<_RawExecutionPolicy> && 53 __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) { 54 __pstl::__simd_fill_n(__first, __last - __first, __value); 55 return __empty{}; 56 } else { 57 std::fill(__first, __last, __value); 58 return __empty{}; 59 } 60 } 61 }; 62 63 } // namespace __pstl 64 _LIBCPP_END_NAMESPACE_STD 65 66 #endif // _LIBCPP___PSTL_CPU_ALGOS_FILL_H 67