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diff --git a/boost/compute/functional/popcount.hpp b/boost/compute/functional/popcount.hpp
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+++ b/boost/compute/functional/popcount.hpp
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+//---------------------------------------------------------------------------//
+// Copyright (c) 2013-2014 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_FUNCTIONAL_POPCOUNT_HPP
+#define BOOST_COMPUTE_FUNCTIONAL_POPCOUNT_HPP
+
+#include <boost/compute/function.hpp>
+#include <boost/compute/type_traits/type_name.hpp>
+
+namespace boost {
+namespace compute {
+
+/// Returns the number of non-zero bits in \p x.
+///
+/// \see_opencl_ref{popcount}
+template<class T>
+class popcount : public function<T(T)>
+{
+public:
+    popcount()
+        : function<T(T)>("boost_popcount")
+    {
+        std::stringstream s;
+        s << "inline " << type_name<T>() << " boost_popcount"
+          << "(const " << type_name<T>() << " x)\n"
+          << "{\n"
+          // use built-in popcount if opencl 1.2 is supported
+          << "#if __OPENCL_VERSION__ >= 120\n"
+          << "    return popcount(x);\n"
+          // fallback to generic popcount() implementation
+          << "#else\n"
+          << "    " << type_name<T>() << " count = 0;\n"
+          << "    for(" << type_name<T>() << " i = 0; i < sizeof(i) * CHAR_BIT; i++){\n"
+          << "        if(x & (" << type_name<T>() << ") 1 << i){\n"
+          << "            count++;\n"
+          << "        }\n"
+          << "    }\n"
+          << "    return count;\n"
+          << "#endif\n"
+          << "}\n";
+        this->set_source(s.str());
+    }
+};
+
+} // end compute namespace
+} // end boost namespace
+
+#endif // BOOST_COMPUTE_FUNCTIONAL_POPCOUNT_HPP