File: context.hpp

package info (click to toggle)
boost1.62 1.62.0+dfsg-10
  • links: PTS, VCS
  • area: main
  • in suites: sid
  • size: 687,152 kB
  • sloc: cpp: 2,613,639; xml: 972,558; ansic: 53,674; python: 32,448; sh: 9,305; asm: 3,071; cs: 2,121; makefile: 967; perl: 859; yacc: 472; php: 132; ruby: 94; f90: 55; sql: 13; csh: 6
file content (245 lines) | stat: -rw-r--r-- 6,566 bytes parent folder | download | duplicates (5)
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
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
//---------------------------------------------------------------------------//
// Copyright (c) 2013 Kyle Lutz <kyle.r.lutz@gmail.com>
//
// Distributed under the Boost Software License, Version 1.0
// See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt
//
// See http://boostorg.github.com/compute for more information.
//---------------------------------------------------------------------------//

#ifndef BOOST_COMPUTE_CONTEXT_HPP
#define BOOST_COMPUTE_CONTEXT_HPP

#include <vector>

#include <boost/throw_exception.hpp>

#include <boost/compute/config.hpp>
#include <boost/compute/device.hpp>
#include <boost/compute/exception/opencl_error.hpp>
#include <boost/compute/detail/assert_cl_success.hpp>

namespace boost {
namespace compute {

/// \class context
/// \brief A compute context.
///
/// The context class represents a compute context.
///
/// A context object manages a set of OpenCL resources including memory
/// buffers and program objects. Before allocating memory on the device or
/// executing kernels you must set up a context object.
///
/// To create a context for the default device on the system:
/// \code
/// // get the default compute device
/// boost::compute::device gpu = boost::compute::system::default_device();
///
/// // create a context for the device
/// boost::compute::context context(gpu);
/// \endcode
///
/// Once a context is created, memory can be allocated using the buffer class
/// and kernels can be executed using the command_queue class.
///
/// \see device, command_queue
class context
{
public:
    /// Create a null context object.
    context()
        : m_context(0)
    {
    }

    /// Creates a new context for \p device with \p properties.
    ///
    /// \see_opencl_ref{clCreateContext}
    explicit context(const device &device,
                     const cl_context_properties *properties = 0)
    {
        BOOST_ASSERT(device.id() != 0);

        cl_device_id device_id = device.id();

        cl_int error = 0;
        m_context = clCreateContext(properties, 1, &device_id, 0, 0, &error);

        if(!m_context){
            BOOST_THROW_EXCEPTION(opencl_error(error));
        }
    }

    /// Creates a new context for \p devices with \p properties.
    ///
    /// \see_opencl_ref{clCreateContext}
    explicit context(const std::vector<device> &devices,
                     const cl_context_properties *properties = 0)
    {
        BOOST_ASSERT(!devices.empty());

        cl_int error = 0;

        m_context = clCreateContext(
            properties,
            static_cast<cl_uint>(devices.size()),
            reinterpret_cast<const cl_device_id *>(&devices[0]),
            0,
            0,
            &error
        );

        if(!m_context){
            BOOST_THROW_EXCEPTION(opencl_error(error));
        }
    }

    /// Creates a new context object for \p context. If \p retain is
    /// \c true, the reference count for \p context will be incremented.
    explicit context(cl_context context, bool retain = true)
        : m_context(context)
    {
        if(m_context && retain){
            clRetainContext(m_context);
        }
    }

    /// Creates a new context object as a copy of \p other.
    context(const context &other)
        : m_context(other.m_context)
    {
        if(m_context){
            clRetainContext(m_context);
        }
    }

    /// Copies the context object from \p other to \c *this.
    context& operator=(const context &other)
    {
        if(this != &other){
            if(m_context){
                clReleaseContext(m_context);
            }

            m_context = other.m_context;

            if(m_context){
                clRetainContext(m_context);
            }
        }

        return *this;
    }

    #ifndef BOOST_COMPUTE_NO_RVALUE_REFERENCES
    /// Move-constructs a new context object from \p other.
    context(context&& other) BOOST_NOEXCEPT
        : m_context(other.m_context)
    {
        other.m_context = 0;
    }

    /// Move-assigns the context from \p other to \c *this.
    context& operator=(context&& other) BOOST_NOEXCEPT
    {
        if(m_context){
            clReleaseContext(m_context);
        }

        m_context = other.m_context;
        other.m_context = 0;

        return *this;
    }
    #endif // BOOST_COMPUTE_NO_RVALUE_REFERENCES

    /// Destroys the context object.
    ~context()
    {
        if(m_context){
            BOOST_COMPUTE_ASSERT_CL_SUCCESS(
                clReleaseContext(m_context)
            );
        }
    }

    /// Returns the underlying OpenCL context.
    cl_context& get() const
    {
        return const_cast<cl_context &>(m_context);
    }

    /// Returns the device for the context. If the context contains multiple
    /// devices, the first is returned.
    device get_device() const
    {
        std::vector<device> devices = get_devices();

        if(devices.empty()) {
            return device();
        }

        return devices.front();
    }

    /// Returns a vector of devices for the context.
    std::vector<device> get_devices() const
    {
        return get_info<std::vector<device> >(CL_CONTEXT_DEVICES);
    }

    /// Returns information about the context.
    ///
    /// \see_opencl_ref{clGetContextInfo}
    template<class T>
    T get_info(cl_context_info info) const
    {
        return detail::get_object_info<T>(clGetContextInfo, m_context, info);
    }

    /// \overload
    template<int Enum>
    typename detail::get_object_info_type<context, Enum>::type
    get_info() const;

    /// Returns \c true if the context is the same as \p other.
    bool operator==(const context &other) const
    {
        return m_context == other.m_context;
    }

    /// Returns \c true if the context is different from \p other.
    bool operator!=(const context &other) const
    {
        return m_context != other.m_context;
    }

    /// \internal_
    operator cl_context() const
    {
        return m_context;
    }

private:
    cl_context m_context;
};

/// \internal_ define get_info() specializations for context
BOOST_COMPUTE_DETAIL_DEFINE_GET_INFO_SPECIALIZATIONS(context,
    ((cl_uint, CL_CONTEXT_REFERENCE_COUNT))
    ((std::vector<cl_device_id>, CL_CONTEXT_DEVICES))
    ((std::vector<cl_context_properties>, CL_CONTEXT_PROPERTIES))
)

#ifdef CL_VERSION_1_1
BOOST_COMPUTE_DETAIL_DEFINE_GET_INFO_SPECIALIZATIONS(context,
    ((cl_uint, CL_CONTEXT_NUM_DEVICES))
)
#endif // CL_VERSION_1_1

} // end compute namespace
} // end boost namespace

#endif // BOOST_COMPUTE_CONTEXT_HPP