File size: 6,780 Bytes
be11144
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
/******************************************************************************
 * Copyright (c) 2011, Duane Merrill.  All rights reserved.
 * Copyright (c) 2011-2018, NVIDIA CORPORATION.  All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the NVIDIA CORPORATION nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL NVIDIA CORPORATION BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 ******************************************************************************/

/**
 * \file
 * Random-access iterator types
 */

#pragma once

#include <iterator>
#include <iostream>

#include "../config.cuh"

#if (THRUST_VERSION >= 100700)
    // This iterator is compatible with Thrust API 1.7 and newer
    #include <thrust/iterator/iterator_facade.h>
    #include <thrust/iterator/iterator_traits.h>
#endif // THRUST_VERSION


/// Optional outer namespace(s)
CUB_NS_PREFIX

/// CUB namespace
namespace cub {


/**
 * \addtogroup UtilIterator
 * @{
 */


/**
 * \brief A discard iterator
 */
template <typename OffsetT = ptrdiff_t>
class DiscardOutputIterator
{
public:

    // Required iterator traits
    typedef DiscardOutputIterator   self_type;              ///< My own type
    typedef OffsetT                 difference_type;        ///< Type to express the result of subtracting one iterator from another
    typedef void                    value_type;             ///< The type of the element the iterator can point to
    typedef void                    pointer;                ///< The type of a pointer to an element the iterator can point to
    typedef void                    reference;              ///< The type of a reference to an element the iterator can point to

#if (THRUST_VERSION >= 100700)
    // Use Thrust's iterator categories so we can use these iterators in Thrust 1.7 (or newer) methods
    typedef typename thrust::detail::iterator_facade_category<
        thrust::any_system_tag,
        thrust::random_access_traversal_tag,
        value_type,
        reference
      >::type iterator_category;                                        ///< The iterator category
#else
    typedef std::random_access_iterator_tag     iterator_category;      ///< The iterator category
#endif  // THRUST_VERSION

private:

    OffsetT offset;

#if defined(_WIN32) || !defined(_WIN64)
    // Workaround for win32 parameter-passing bug (ulonglong2 argmin DeviceReduce)
    OffsetT pad[CUB_MAX(1, (16 / sizeof(OffsetT) - 1))];
#endif

public:

    /// Constructor
    __host__ __device__ __forceinline__ DiscardOutputIterator(
        OffsetT offset = 0)     ///< Base offset
    :
        offset(offset)
    {}

    /// Postfix increment
    __host__ __device__ __forceinline__ self_type operator++(int)
    {
        self_type retval = *this;
        offset++;
        return retval;
    }

    /// Prefix increment
    __host__ __device__ __forceinline__ self_type operator++()
    {
        offset++;
        return *this;
    }

    /// Indirection
    __host__ __device__ __forceinline__ self_type& operator*()
    {
        // return self reference, which can be assigned to anything
        return *this;
    }

    /// Addition
    template <typename Distance>
    __host__ __device__ __forceinline__ self_type operator+(Distance n) const
    {
        self_type retval(offset + n);
        return retval;
    }

    /// Addition assignment
    template <typename Distance>
    __host__ __device__ __forceinline__ self_type& operator+=(Distance n)
    {
        offset += n;
        return *this;
    }

    /// Subtraction
    template <typename Distance>
    __host__ __device__ __forceinline__ self_type operator-(Distance n) const
    {
        self_type retval(offset - n);
        return retval;
    }

    /// Subtraction assignment
    template <typename Distance>
    __host__ __device__ __forceinline__ self_type& operator-=(Distance n)
    {
        offset -= n;
        return *this;
    }

    /// Distance
    __host__ __device__ __forceinline__ difference_type operator-(self_type other) const
    {
        return offset - other.offset;
    }

    /// Array subscript
    template <typename Distance>
    __host__ __device__ __forceinline__ self_type& operator[](Distance n)
    {
        // return self reference, which can be assigned to anything
        return *this;
    }

    /// Structure dereference
    __host__ __device__ __forceinline__ pointer operator->()
    {
        return;
    }

    /// Assignment to self (no-op)
    __host__ __device__ __forceinline__ void operator=(self_type const& other)
    {
        offset = other.offset;
    }

    /// Assignment to anything else (no-op)
    template<typename T>
    __host__ __device__ __forceinline__ void operator=(T const&)
    {}

    /// Cast to void* operator
    __host__ __device__ __forceinline__ operator void*() const { return NULL; }

    /// Equal to
    __host__ __device__ __forceinline__ bool operator==(const self_type& rhs)
    {
        return (offset == rhs.offset);
    }

    /// Not equal to
    __host__ __device__ __forceinline__ bool operator!=(const self_type& rhs)
    {
        return (offset != rhs.offset);
    }

    /// ostream operator
    friend std::ostream& operator<<(std::ostream& os, const self_type& itr)
    {
        os << "[" << itr.offset << "]";
        return os;
    }

};


/** @} */       // end group UtilIterator

}               // CUB namespace
CUB_NS_POSTFIX  // Optional outer namespace(s)