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// -*- C++ -*- |
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//===-- parallel_backend_serial.h -----------------------------------------===// |
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// |
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
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// See https://llvm.org/LICENSE.txt for license information. |
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
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// |
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//===----------------------------------------------------------------------===// |
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|
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#ifndef _PSTL_PARALLEL_BACKEND_SERIAL_H |
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#define _PSTL_PARALLEL_BACKEND_SERIAL_H |
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|
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#include <algorithm> |
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#include <cstddef> |
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#include <memory> |
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#include <numeric> |
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#include <utility> |
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|
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namespace __pstl |
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{ |
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namespace __serial_backend |
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{ |
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|
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template <typename _Tp> |
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class __buffer |
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{ |
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std::allocator<_Tp> __allocator_; |
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_Tp* __ptr_; |
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const std::size_t __buf_size_; |
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__buffer(const __buffer&) = delete; |
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void |
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operator=(const __buffer&) = delete; |
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|
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public: |
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__buffer(std::size_t __n) : __allocator_(), __ptr_(__allocator_.allocate(__n)), __buf_size_(__n) {} |
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|
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operator bool() const { return __ptr_ != nullptr; } |
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_Tp* |
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get() const |
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{ |
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return __ptr_; |
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} |
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~__buffer() { __allocator_.deallocate(__ptr_, __buf_size_); } |
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}; |
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|
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inline void |
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__cancel_execution() |
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{ |
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} |
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|
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template <class _ExecutionPolicy, class _Index, class _Fp> |
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void |
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__parallel_for(_ExecutionPolicy&&, _Index __first, _Index __last, _Fp __f) |
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{ |
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__f(__first, __last); |
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} |
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|
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template <class _ExecutionPolicy, class _Value, class _Index, typename _RealBody, typename _Reduction> |
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_Value |
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__parallel_reduce(_ExecutionPolicy&&, _Index __first, _Index __last, const _Value& __identity, |
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const _RealBody& __real_body, const _Reduction&) |
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{ |
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if (__first == __last) |
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{ |
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return __identity; |
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} |
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else |
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{ |
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return __real_body(__first, __last, __identity); |
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} |
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} |
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|
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template <class _ExecutionPolicy, class _Index, class _UnaryOp, class _Tp, class _BinaryOp, class _Reduce> |
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_Tp |
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__parallel_transform_reduce(_ExecutionPolicy&&, _Index __first, _Index __last, _UnaryOp, _Tp __init, _BinaryOp, |
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_Reduce __reduce) |
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{ |
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return __reduce(__first, __last, __init); |
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} |
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|
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template <class _ExecutionPolicy, typename _Index, typename _Tp, typename _Rp, typename _Cp, typename _Sp, typename _Ap> |
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void |
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__parallel_strict_scan(_ExecutionPolicy&&, _Index __n, _Tp __initial, _Rp __reduce, _Cp __combine, _Sp __scan, |
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_Ap __apex) |
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{ |
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_Tp __sum = __initial; |
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if (__n) |
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__sum = __combine(__sum, __reduce(_Index(0), __n)); |
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__apex(__sum); |
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if (__n) |
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__scan(_Index(0), __n, __initial); |
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} |
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|
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template <class _ExecutionPolicy, class _Index, class _UnaryOp, class _Tp, class _BinaryOp, class _Reduce, class _Scan> |
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_Tp |
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__parallel_transform_scan(_ExecutionPolicy&&, _Index __n, _UnaryOp, _Tp __init, _BinaryOp, _Reduce, _Scan __scan) |
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{ |
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return __scan(_Index(0), __n, __init); |
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} |
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|
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template <class _ExecutionPolicy, typename _RandomAccessIterator, typename _Compare, typename _LeafSort> |
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void |
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__parallel_stable_sort(_ExecutionPolicy&&, _RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp, |
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_LeafSort __leaf_sort, std::size_t = 0) |
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{ |
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__leaf_sort(__first, __last, __comp); |
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} |
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|
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template <class _ExecutionPolicy, typename _RandomAccessIterator1, typename _RandomAccessIterator2, |
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typename _RandomAccessIterator3, typename _Compare, typename _LeafMerge> |
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void |
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__parallel_merge(_ExecutionPolicy&&, _RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1, |
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_RandomAccessIterator2 __first2, _RandomAccessIterator2 __last2, _RandomAccessIterator3 __outit, |
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_Compare __comp, _LeafMerge __leaf_merge) |
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{ |
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__leaf_merge(__first1, __last1, __first2, __last2, __outit, __comp); |
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} |
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|
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template <class _ExecutionPolicy, typename _F1, typename _F2> |
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void |
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__parallel_invoke(_ExecutionPolicy&&, _F1&& __f1, _F2&& __f2) |
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{ |
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std::forward<_F1>(__f1)(); |
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std::forward<_F2>(__f2)(); |
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} |
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|
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} // namespace __serial_backend |
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} // namespace __pstl |
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|
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#endif /* _PSTL_PARALLEL_BACKEND_SERIAL_H */ |
