ecency-mobile/ios/Pods/boost-for-react-native/boost/mpi/operations.hpp

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9.8 KiB
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// Copyright (C) 2004 The Trustees of Indiana University.
// Copyright (C) 2005-2006 Douglas Gregor <doug.gregor -at- gmail.com>
// Use, modification and distribution is subject to 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)
// Authors: Douglas Gregor
// Andrew Lumsdaine
/** @file operations.hpp
*
* This header provides a mapping from function objects to @c MPI_Op
* constants used in MPI collective operations. It also provides
* several new function object types not present in the standard @c
* <functional> header that have direct mappings to @c MPI_Op.
*/
#ifndef BOOST_MPI_IS_MPI_OP_HPP
#define BOOST_MPI_IS_MPI_OP_HPP
#include <boost/mpi/config.hpp>
#include <boost/mpl/bool.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/and.hpp>
#include <boost/mpi/datatype.hpp>
#include <boost/utility/enable_if.hpp>
#include <functional>
namespace boost { namespace mpi {
template<typename Op, typename T> struct is_mpi_op;
/**
* @brief Determine if a function object type is commutative.
*
* This trait determines if an operation @c Op is commutative when
* applied to values of type @c T. Parallel operations such as @c
* reduce and @c prefix_sum can be implemented more efficiently with
* commutative operations. To mark an operation as commutative, users
* should specialize @c is_commutative and derive from the class @c
* mpl::true_.
*/
template<typename Op, typename T>
struct is_commutative : public mpl::false_ { };
/**************************************************************************
* Function objects for MPI operations not in <functional> header *
**************************************************************************/
/**
* @brief Compute the maximum of two values.
*
* This binary function object computes the maximum of the two values
* it is given. When used with MPI and a type @c T that has an
* associated, built-in MPI data type, translates to @c MPI_MAX.
*/
template<typename T>
struct maximum : public std::binary_function<T, T, T>
{
/** @returns the maximum of x and y. */
const T& operator()(const T& x, const T& y) const
{
return x < y? y : x;
}
};
/**
* @brief Compute the minimum of two values.
*
* This binary function object computes the minimum of the two values
* it is given. When used with MPI and a type @c T that has an
* associated, built-in MPI data type, translates to @c MPI_MIN.
*/
template<typename T>
struct minimum : public std::binary_function<T, T, T>
{
/** @returns the minimum of x and y. */
const T& operator()(const T& x, const T& y) const
{
return x < y? x : y;
}
};
/**
* @brief Compute the bitwise AND of two integral values.
*
* This binary function object computes the bitwise AND of the two
* values it is given. When used with MPI and a type @c T that has an
* associated, built-in MPI data type, translates to @c MPI_BAND.
*/
template<typename T>
struct bitwise_and : public std::binary_function<T, T, T>
{
/** @returns @c x & y. */
T operator()(const T& x, const T& y) const
{
return x & y;
}
};
/**
* @brief Compute the bitwise OR of two integral values.
*
* This binary function object computes the bitwise OR of the two
* values it is given. When used with MPI and a type @c T that has an
* associated, built-in MPI data type, translates to @c MPI_BOR.
*/
template<typename T>
struct bitwise_or : public std::binary_function<T, T, T>
{
/** @returns the @c x | y. */
T operator()(const T& x, const T& y) const
{
return x | y;
}
};
/**
* @brief Compute the logical exclusive OR of two integral values.
*
* This binary function object computes the logical exclusive of the
* two values it is given. When used with MPI and a type @c T that has
* an associated, built-in MPI data type, translates to @c MPI_LXOR.
*/
template<typename T>
struct logical_xor : public std::binary_function<T, T, T>
{
/** @returns the logical exclusive OR of x and y. */
T operator()(const T& x, const T& y) const
{
return (x || y) && !(x && y);
}
};
/**
* @brief Compute the bitwise exclusive OR of two integral values.
*
* This binary function object computes the bitwise exclusive OR of
* the two values it is given. When used with MPI and a type @c T that
* has an associated, built-in MPI data type, translates to @c
* MPI_BXOR.
*/
template<typename T>
struct bitwise_xor : public std::binary_function<T, T, T>
{
/** @returns @c x ^ y. */
T operator()(const T& x, const T& y) const
{
return x ^ y;
}
};
/**************************************************************************
* MPI_Op queries *
**************************************************************************/
/**
* @brief Determine if a function object has an associated @c MPI_Op.
*
* This trait determines if a function object type @c Op, when used
* with argument type @c T, has an associated @c MPI_Op. If so, @c
* is_mpi_op<Op,T> will derive from @c mpl::false_ and will
* contain a static member function @c op that takes no arguments but
* returns the associated @c MPI_Op value. For instance, @c
* is_mpi_op<std::plus<int>,int>::op() returns @c MPI_SUM.
*
* Users may specialize @c is_mpi_op for any other class templates
* that map onto operations that have @c MPI_Op equivalences, such as
* bitwise OR, logical and, or maximum. However, users are encouraged
* to use the standard function objects in the @c functional and @c
* boost/mpi/operations.hpp headers whenever possible. For
* function objects that are class templates with a single template
* parameter, it may be easier to specialize @c is_builtin_mpi_op.
*/
template<typename Op, typename T>
struct is_mpi_op : public mpl::false_ { };
/// INTERNAL ONLY
template<typename T>
struct is_mpi_op<maximum<T>, T>
: public boost::mpl::or_<is_mpi_integer_datatype<T>,
is_mpi_floating_point_datatype<T> >
{
static MPI_Op op() { return MPI_MAX; }
};
/// INTERNAL ONLY
template<typename T>
struct is_mpi_op<minimum<T>, T>
: public boost::mpl::or_<is_mpi_integer_datatype<T>,
is_mpi_floating_point_datatype<T> >
{
static MPI_Op op() { return MPI_MIN; }
};
/// INTERNAL ONLY
template<typename T>
struct is_mpi_op<std::plus<T>, T>
: public boost::mpl::or_<is_mpi_integer_datatype<T>,
is_mpi_floating_point_datatype<T>,
is_mpi_complex_datatype<T> >
{
static MPI_Op op() { return MPI_SUM; }
};
/// INTERNAL ONLY
template<typename T>
struct is_mpi_op<std::multiplies<T>, T>
: public boost::mpl::or_<is_mpi_integer_datatype<T>,
is_mpi_floating_point_datatype<T>,
is_mpi_complex_datatype<T> >
{
static MPI_Op op() { return MPI_PROD; }
};
/// INTERNAL ONLY
template<typename T>
struct is_mpi_op<std::logical_and<T>, T>
: public boost::mpl::or_<is_mpi_integer_datatype<T>,
is_mpi_logical_datatype<T> >
{
static MPI_Op op() { return MPI_LAND; }
};
/// INTERNAL ONLY
template<typename T>
struct is_mpi_op<std::logical_or<T>, T>
: public boost::mpl::or_<is_mpi_integer_datatype<T>,
is_mpi_logical_datatype<T> >
{
static MPI_Op op() { return MPI_LOR; }
};
/// INTERNAL ONLY
template<typename T>
struct is_mpi_op<logical_xor<T>, T>
: public boost::mpl::or_<is_mpi_integer_datatype<T>,
is_mpi_logical_datatype<T> >
{
static MPI_Op op() { return MPI_LXOR; }
};
/// INTERNAL ONLY
template<typename T>
struct is_mpi_op<bitwise_and<T>, T>
: public boost::mpl::or_<is_mpi_integer_datatype<T>,
is_mpi_byte_datatype<T> >
{
static MPI_Op op() { return MPI_BAND; }
};
/// INTERNAL ONLY
template<typename T>
struct is_mpi_op<bitwise_or<T>, T>
: public boost::mpl::or_<is_mpi_integer_datatype<T>,
is_mpi_byte_datatype<T> >
{
static MPI_Op op() { return MPI_BOR; }
};
/// INTERNAL ONLY
template<typename T>
struct is_mpi_op<bitwise_xor<T>, T>
: public boost::mpl::or_<is_mpi_integer_datatype<T>,
is_mpi_byte_datatype<T> >
{
static MPI_Op op() { return MPI_BXOR; }
};
namespace detail {
// A helper class used to create user-defined MPI_Ops
template<typename Op, typename T>
class user_op
{
public:
explicit user_op(Op& op)
{
BOOST_MPI_CHECK_RESULT(MPI_Op_create,
(&user_op<Op, T>::perform,
is_commutative<Op, T>::value,
&mpi_op));
op_ptr = &op;
}
~user_op()
{
if (std::uncaught_exception()) {
// Ignore failure cases: there are obviously other problems
// already, and we don't want to cause program termination if
// MPI_Op_free fails.
MPI_Op_free(&mpi_op);
} else {
BOOST_MPI_CHECK_RESULT(MPI_Op_free, (&mpi_op));
}
}
MPI_Op& get_mpi_op()
{
return mpi_op;
}
private:
MPI_Op mpi_op;
static Op* op_ptr;
static void BOOST_MPI_CALLING_CONVENTION perform(void* vinvec, void* voutvec, int* plen, MPI_Datatype*)
{
T* invec = static_cast<T*>(vinvec);
T* outvec = static_cast<T*>(voutvec);
std::transform(invec, invec + *plen, outvec, outvec, *op_ptr);
}
};
template<typename Op, typename T> Op* user_op<Op, T>::op_ptr = 0;
} // end namespace detail
} } // end namespace boost::mpi
#endif // BOOST_MPI_GET_MPI_OP_HPP