ceph/src/boost/libs/compute/include/boost/compute/function.hpp

   1 //---------------------------------------------------------------------------//
   2 // Copyright (c) 2013 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_FUNCTION_HPP
  12 #define BOOST_COMPUTE_FUNCTION_HPP
  13
  14 #include <map>
  15 #include <string>
  16 #include <sstream>
  17 #include <vector>
  18
  19 #include <boost/assert.hpp>
  20 #include <boost/config.hpp>
  21 #include <boost/function_types/parameter_types.hpp>
  22 #include <boost/preprocessor/repetition.hpp>
  23 #include <boost/mpl/for_each.hpp>
  24 #include <boost/mpl/size.hpp>
  25 #include <boost/mpl/transform.hpp>
  26 #include <boost/static_assert.hpp>
  27 #include <boost/tuple/tuple.hpp>
  28 #include <boost/type_traits/add_pointer.hpp>
  29 #include <boost/type_traits/function_traits.hpp>
  30
  31 #include <boost/compute/cl.hpp>
  32 #include <boost/compute/config.hpp>
  33 #include <boost/compute/type_traits/type_name.hpp>
  34
  35 namespace boost {
  36 namespace compute {
  37 namespace detail {
  38
  39 template<class ResultType, class ArgTuple>
  40 class invoked_function
  41 {
  42 public:
  43     typedef ResultType result_type;
  44
  45     BOOST_STATIC_CONSTANT(
  46         size_t, arity = boost::tuples::length<ArgTuple>::value
  47     );
  48
  49     invoked_function(const std::string &name,
  50                      const std::string &source)
  51         : m_name(name),
  52           m_source(source)
  53     {
  54     }
  55
  56     invoked_function(const std::string &name,
  57                      const std::string &source,
  58                      const std::map<std::string, std::string> &definitions)
  59         : m_name(name),
  60           m_source(source),
  61           m_definitions(definitions)
  62     {
  63     }
  64
  65     invoked_function(const std::string &name,
  66                      const std::string &source,
  67                      const ArgTuple &args)
  68         : m_name(name),
  69           m_source(source),
  70           m_args(args)
  71     {
  72     }
  73
  74     invoked_function(const std::string &name,
  75                      const std::string &source,
  76                      const std::map<std::string, std::string> &definitions,
  77                      const ArgTuple &args)
  78         : m_name(name),
  79           m_source(source),
  80           m_definitions(definitions),
  81           m_args(args)
  82     {
  83     }
  84
  85     std::string name() const
  86     {
  87         return m_name;
  88     }
  89
  90     std::string source() const
  91     {
  92         return m_source;
  93     }
  94
  95     const std::map<std::string, std::string>& definitions() const
  96     {
  97         return m_definitions;
  98     }
  99
 100     const ArgTuple& args() const
 101     {
 102         return m_args;
 103     }
 104
 105 private:
 106     std::string m_name;
 107     std::string m_source;
 108     std::map<std::string, std::string> m_definitions;
 109     ArgTuple m_args;
 110 };
 111
 112 } // end detail namespace
 113
 114 /// \class function
 115 /// \brief A function object.
 116 template<class Signature>
 117 class function
 118 {
 119 public:
 120     /// \internal_
 121     typedef typename
 122         boost::function_traits<Signature>::result_type result_type;
 123
 124     /// \internal_
 125     BOOST_STATIC_CONSTANT(
 126         size_t, arity = boost::function_traits<Signature>::arity
 127     );
 128
 129     /// \internal_
 130     typedef Signature signature;
 131
 132     /// Creates a new function object with \p name.
 133     function(const std::string &name)
 134         : m_name(name)
 135     {
 136     }
 137
 138     /// Destroys the function object.
 139     ~function()
 140     {
 141     }
 142
 143     /// \internal_
 144     std::string name() const
 145     {
 146         return m_name;
 147     }
 148
 149     /// \internal_
 150     void set_source(const std::string &source)
 151     {
 152         m_source = source;
 153     }
 154
 155     /// \internal_
 156     std::string source() const
 157     {
 158         return m_source;
 159     }
 160
 161     /// \internal_
 162     void define(std::string name, std::string value = std::string())
 163     {
 164         m_definitions[name] = value;
 165     }
 166
 167     /// \internal_
 168     detail::invoked_function<result_type, boost::tuple<> >
 169     operator()() const
 170     {
 171         BOOST_STATIC_ASSERT_MSG(
 172             arity == 0,
 173             "Non-nullary function invoked with zero arguments"
 174         );
 175
 176         return detail::invoked_function<result_type, boost::tuple<> >(
 177             m_name, m_source, m_definitions
 178         );
 179     }
 180
 181     /// \internal_
 182     template<class Arg1>
 183     detail::invoked_function<result_type, boost::tuple<Arg1> >
 184     operator()(const Arg1 &arg1) const
 185     {
 186         BOOST_STATIC_ASSERT_MSG(
 187             arity == 1,
 188             "Non-unary function invoked one argument"
 189         );
 190
 191         return detail::invoked_function<result_type, boost::tuple<Arg1> >(
 192             m_name, m_source, m_definitions, boost::make_tuple(arg1)
 193         );
 194     }
 195
 196     /// \internal_
 197     template<class Arg1, class Arg2>
 198     detail::invoked_function<result_type, boost::tuple<Arg1, Arg2> >
 199     operator()(const Arg1 &arg1, const Arg2 &arg2) const
 200     {
 201         BOOST_STATIC_ASSERT_MSG(
 202             arity == 2,
 203             "Non-binary function invoked with two arguments"
 204         );
 205
 206         return detail::invoked_function<result_type, boost::tuple<Arg1, Arg2> >(
 207             m_name, m_source, m_definitions, boost::make_tuple(arg1, arg2)
 208         );
 209     }
 210
 211     /// \internal_
 212     template<class Arg1, class Arg2, class Arg3>
 213     detail::invoked_function<result_type, boost::tuple<Arg1, Arg2, Arg3> >
 214     operator()(const Arg1 &arg1, const Arg2 &arg2, const Arg3 &arg3) const
 215     {
 216         BOOST_STATIC_ASSERT_MSG(
 217             arity == 3,
 218             "Non-ternary function invoked with three arguments"
 219         );
 220
 221         return detail::invoked_function<result_type, boost::tuple<Arg1, Arg2, Arg3> >(
 222             m_name, m_source, m_definitions, boost::make_tuple(arg1, arg2, arg3)
 223         );
 224     }
 225
 226 private:
 227     std::string m_name;
 228     std::string m_source;
 229     std::map<std::string, std::string> m_definitions;
 230 };
 231
 232 /// Creates a function object given its \p name and \p source.
 233 ///
 234 /// \param name The function name.
 235 /// \param source The function source code.
 236 ///
 237 /// \see BOOST_COMPUTE_FUNCTION()
 238 template<class Signature>
 239 inline function<Signature>
 240 make_function_from_source(const std::string &name, const std::string &source)
 241 {
 242     function<Signature> f(name);
 243     f.set_source(source);
 244     return f;
 245 }
 246
 247 namespace detail {
 248
 249 // given a string containing the arguments declaration for a function
 250 // like: "(int a, const float b)", returns a vector containing the name
 251 // of each argument (e.g. ["a", "b"]).
 252 inline std::vector<std::string> parse_argument_names(const char *arguments)
 253 {
 254     BOOST_ASSERT_MSG(
 255         arguments[0] == '(' && arguments[std::strlen(arguments)-1] == ')',
 256         "Arguments should start and end with parentheses"
 257     );
 258
 259     std::vector<std::string> args;
 260
 261     size_t last_space = 0;
 262     size_t skip_comma = 0;
 263     for(size_t i = 1; i < std::strlen(arguments) - 2; i++){
 264         const char c = arguments[i];
 265
 266         if(c == ' '){
 267             last_space = i;
 268         }
 269         else if(c == ',' && !skip_comma){
 270             std::string name(
 271                 arguments + last_space + 1, i - last_space - 1
 272             );
 273             args.push_back(name);
 274         }
 275         else if(c == '<'){
 276             skip_comma++;
 277         }
 278         else if(c == '>'){
 279             skip_comma--;
 280         }
 281     }
 282
 283     std::string last_argument(
 284         arguments + last_space + 1, std::strlen(arguments) - last_space - 2
 285     );
 286     args.push_back(last_argument);
 287
 288     return args;
 289 }
 290
 291 struct signature_argument_inserter
 292 {
 293     signature_argument_inserter(std::stringstream &s_, const char *arguments, size_t last)
 294         : s(s_)
 295     {
 296         n = 0;
 297         m_last = last;
 298
 299         m_argument_names = parse_argument_names(arguments);
 300
 301         BOOST_ASSERT_MSG(
 302             m_argument_names.size() == last,
 303             "Wrong number of arguments"
 304         );
 305     }
 306
 307     template<class T>
 308     void operator()(const T*)
 309     {
 310         s << type_name<T>() << " " << m_argument_names[n];
 311         if(n+1 < m_last){
 312             s << ", ";
 313         }
 314         n++;
 315     }
 316
 317     size_t n;
 318     size_t m_last;
 319     std::stringstream &s;
 320     std::vector<std::string> m_argument_names;
 321 };
 322
 323 template<class Signature>
 324 inline std::string make_function_declaration(const char *name, const char *arguments)
 325 {
 326     typedef typename
 327         boost::function_traits<Signature>::result_type result_type;
 328     typedef typename
 329         boost::function_types::parameter_types<Signature>::type parameter_types;
 330     typedef typename
 331         mpl::size<parameter_types>::type arity_type;
 332
 333     std::stringstream s;
 334     s << "inline " << type_name<result_type>() << " " << name;
 335     s << "(";
 336
 337     if(arity_type::value > 0){
 338         signature_argument_inserter i(s, arguments, arity_type::value);
 339         mpl::for_each<
 340             typename mpl::transform<parameter_types, boost::add_pointer<mpl::_1>
 341         >::type>(i);
 342     }
 343
 344     s << ")";
 345     return s.str();
 346 }
 347
 348 struct argument_list_inserter
 349 {
 350     argument_list_inserter(std::stringstream &s_, const char first, size_t last)
 351         : s(s_)
 352     {
 353         n = 0;
 354         m_last = last;
 355         m_name = first;
 356     }
 357
 358     template<class T>
 359     void operator()(const T*)
 360     {
 361         s << type_name<T>() << " " << m_name++;
 362         if(n+1 < m_last){
 363             s << ", ";
 364         }
 365         n++;
 366     }
 367
 368     size_t n;
 369     size_t m_last;
 370     char m_name;
 371     std::stringstream &s;
 372 };
 373
 374 template<class Signature>
 375 inline std::string generate_argument_list(const char first = 'a')
 376 {
 377     typedef typename
 378         boost::function_types::parameter_types<Signature>::type parameter_types;
 379     typedef typename
 380         mpl::size<parameter_types>::type arity_type;
 381
 382     std::stringstream s;
 383     s << '(';
 384
 385     if(arity_type::value > 0){
 386         argument_list_inserter i(s, first, arity_type::value);
 387         mpl::for_each<
 388             typename mpl::transform<parameter_types, boost::add_pointer<mpl::_1>
 389         >::type>(i);
 390     }
 391
 392     s << ')';
 393     return s.str();
 394 }
 395
 396 // used by the BOOST_COMPUTE_FUNCTION() macro to create a function
 397 // with the given signature, name, arguments, and source.
 398 template<class Signature>
 399 inline function<Signature>
 400 make_function_impl(const char *name, const char *arguments, const char *source)
 401 {
 402     std::stringstream s;
 403     s << make_function_declaration<Signature>(name, arguments);
 404     s << source;
 405
 406     return make_function_from_source<Signature>(name, s.str());
 407 }
 408
 409 } // end detail namespace
 410 } // end compute namespace
 411 } // end boost namespace
 412
 413 /// Creates a function object with \p name and \p source.
 414 ///
 415 /// \param return_type The return type for the function.
 416 /// \param name The name of the function.
 417 /// \param arguments A list of arguments for the function.
 418 /// \param source The OpenCL C source code for the function.
 419 ///
 420 /// The function declaration and signature are automatically created using
 421 /// the \p return_type, \p name, and \p arguments macro parameters.
 422 ///
 423 /// The source code for the function is interpreted as OpenCL C99 source code
 424 /// which is stringified and passed to the OpenCL compiler when the function
 425 /// is invoked.
 426 ///
 427 /// For example, to create a function which squares a number:
 428 /// \code
 429 /// BOOST_COMPUTE_FUNCTION(float, square, (float x),
 430 /// {
 431 ///     return x * x;
 432 /// });
 433 /// \endcode
 434 ///
 435 /// And to create a function which sums two numbers:
 436 /// \code
 437 /// BOOST_COMPUTE_FUNCTION(int, sum_two, (int x, int y),
 438 /// {
 439 ///     return x + y;
 440 /// });
 441 /// \endcode
 442 ///
 443 /// \see BOOST_COMPUTE_CLOSURE()
 444 #ifdef BOOST_COMPUTE_DOXYGEN_INVOKED
 445 #define BOOST_COMPUTE_FUNCTION(return_type, name, arguments, source)
 446 #else
 447 #define BOOST_COMPUTE_FUNCTION(return_type, name, arguments, ...) \
 448     ::boost::compute::function<return_type arguments> name = \
 449         ::boost::compute::detail::make_function_impl<return_type arguments>( \
 450             #name, #arguments, #__VA_ARGS__ \
 451         )
 452 #endif
 453
 454 #endif // BOOST_COMPUTE_FUNCTION_HPP