projects / ceph.git / blame
| Commit | Line | Data |
|---|---|---|
| 7c673cae FG |
1 | //---------------------------------------------------------------------------// |
| 2 | // Copyright (c) 2013-2014 Kyle Lutz <kyle.r.lutz@gmail.com> | |
| 3 | // | |
| 4 | // Distributed under the Boost Software License, Version 1.0 | |
| 5 | // See accompanying file LICENSE_1_0.txt or copy at | |
| 6 | // http://www.boost.org/LICENSE_1_0.txt | |
| 7 | // | |
| 8 | // See http://boostorg.github.com/compute for more information. | |
| 9 | //---------------------------------------------------------------------------// | |
| 10 | ||
| 11 | #ifndef BOOST_COMPUTE_FUNCTIONAL_POPCOUNT_HPP | |
| 12 | #define BOOST_COMPUTE_FUNCTIONAL_POPCOUNT_HPP | |
| 13 | ||
| 14 | #include <boost/compute/function.hpp> | |
| 15 | #include <boost/compute/type_traits/type_name.hpp> | |
| 16 | ||
| 17 | namespace boost { | |
| 18 | namespace compute { | |
| 19 | ||
| 20 | /// Returns the number of non-zero bits in \p x. | |
| 21 | /// | |
| 22 | /// \see_opencl_ref{popcount} | |
| 23 | template<class T> | |
| 24 | class popcount : public function<T(T)> | |
| 25 | { | |
| 26 | public: | |
| 27 | popcount() | |
| 28 | : function<T(T)>("boost_popcount") | |
| 29 | { | |
| 30 | std::stringstream s; | |
| 31 | s << "inline " << type_name<T>() << " boost_popcount" | |
| 32 | << "(const " << type_name<T>() << " x)\n" | |
| 33 | << "{\n" | |
| 34 | // use built-in popcount if opencl 1.2 is supported | |
| 35 | << "#if __OPENCL_VERSION__ >= 120\n" | |
| 36 | << " return popcount(x);\n" | |
| 37 | // fallback to generic popcount() implementation | |
| 38 | << "#else\n" | |
| 39 | << " " << type_name<T>() << " count = 0;\n" | |
| 40 | << " for(" << type_name<T>() << " i = 0; i < sizeof(i) * CHAR_BIT; i++){\n" | |
| 41 | << " if(x & (" << type_name<T>() << ") 1 << i){\n" | |
| 42 | << " count++;\n" | |
| 43 | << " }\n" | |
| 44 | << " }\n" | |
| 45 | << " return count;\n" | |
| 46 | << "#endif\n" | |
| 47 | << "}\n"; | |
| 48 | this->set_source(s.str()); | |
| 49 | } | |
| 50 | }; | |
| 51 | ||
| 52 | } // end compute namespace | |
| 53 | } // end boost namespace | |
| 54 | ||
| 55 | #endif // BOOST_COMPUTE_FUNCTIONAL_POPCOUNT_HPP |