File size: 3,550 Bytes
2a504a6 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 | /*
* Copyright 2008-2013 NVIDIA Corporation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*! \file scan.h
* \brief Sequential implementations of scan functions.
*/
#pragma once
#include <thrust/detail/config.h>
#if defined(_CCCL_IMPLICIT_SYSTEM_HEADER_GCC)
# pragma GCC system_header
#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_CLANG)
# pragma clang system_header
#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_MSVC)
# pragma system_header
#endif // no system header
#include <thrust/system/detail/sequential/execution_policy.h>
#include <thrust/iterator/iterator_traits.h>
#include <thrust/detail/type_traits.h>
#include <thrust/detail/type_traits/function_traits.h>
#include <thrust/detail/type_traits/iterator/is_output_iterator.h>
#include <thrust/detail/function.h>
THRUST_NAMESPACE_BEGIN
namespace system
{
namespace detail
{
namespace sequential
{
__thrust_exec_check_disable__
template<typename DerivedPolicy,
typename InputIterator,
typename OutputIterator,
typename BinaryFunction>
__host__ __device__
OutputIterator inclusive_scan(sequential::execution_policy<DerivedPolicy> &,
InputIterator first,
InputIterator last,
OutputIterator result,
BinaryFunction binary_op)
{
using namespace thrust::detail;
// Use the input iterator's value type per https://wg21.link/P0571
using ValueType = typename thrust::iterator_value<InputIterator>::type;
// wrap binary_op
thrust::detail::wrapped_function<
BinaryFunction,
ValueType
> wrapped_binary_op(binary_op);
if(first != last)
{
ValueType sum = *first;
*result = *first;
for(++first, ++result; first != last; ++first, ++result)
*result = sum = wrapped_binary_op(sum,*first);
}
return result;
}
__thrust_exec_check_disable__
template<typename DerivedPolicy,
typename InputIterator,
typename OutputIterator,
typename InitialValueType,
typename BinaryFunction>
__host__ __device__
OutputIterator exclusive_scan(sequential::execution_policy<DerivedPolicy> &,
InputIterator first,
InputIterator last,
OutputIterator result,
InitialValueType init,
BinaryFunction binary_op)
{
using namespace thrust::detail;
// Use the initial value type per https://wg21.link/P0571
using ValueType = InitialValueType;
if(first != last)
{
ValueType tmp = *first; // temporary value allows in-situ scan
ValueType sum = init;
*result = sum;
sum = binary_op(sum, tmp);
for(++first, ++result; first != last; ++first, ++result)
{
tmp = *first;
*result = sum;
sum = binary_op(sum, tmp);
}
}
return result;
}
} // end namespace sequential
} // end namespace detail
} // end namespace system
THRUST_NAMESPACE_END
|