Teuchos_MpiReductionOpSetter.hpp

// @HEADER
// ***********************************************************************
//
//                    Teuchos: Common Tools Package
//                 Copyright (2004) Sandia Corporation
//
// Under terms of Contract DE-AC04-94AL85000, there is a non-exclusive
// license for use of this work by or on behalf of the U.S. Government.
//
// This library is free software; you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation; either version 2.1 of the
// License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
// USA
// Questions? Contact Michael A. Heroux (maherou@sandia.gov)
//
// ***********************************************************************
// @HEADER

#ifndef TEUCHOS_MPI_REDUCTION_OP_SETTER_HPP
#define TEUCHOS_MPI_REDUCTION_OP_SETTER_HPP

#include "Teuchos_RCP.hpp"
#include "Teuchos_ReductionOp.hpp"
#include "mpi.h"

namespace Teuchos {

class TEUCHOS_LIB_DLL_EXPORT MpiReductionOpBase : virtual public Describable {
public:
  virtual void reduce(
    void              *invec
    ,void             *inoutvec
    ,int              *len
    ,MPI_Datatype     *datatype
    ) const = 0;
};

template<typename Ordinal>
class MpiReductionOp : public MpiReductionOpBase {
public:
  MpiReductionOp( const RCP<const ValueTypeReductionOp<Ordinal,char> > &reductOp );
  void reduce(
    void              *invec
    ,void             *inoutvec
    ,int              *len
    ,MPI_Datatype     *datatype
    ) const;
private:
  RCP<const ValueTypeReductionOp<Ordinal,char> > reductOp_;
  // Not defined and not to be called
  MpiReductionOp();
  MpiReductionOp(const MpiReductionOp&);
  MpiReductionOp& operator=(const MpiReductionOp&);
};

template<typename Ordinal>
RCP<const MpiReductionOp<Ordinal> >
mpiReductionOp( const RCP<const ValueTypeReductionOp<Ordinal,char> > &reductOp );

class TEUCHOS_LIB_DLL_EXPORT MpiReductionOpSetter {
public:

  MpiReductionOpSetter( const Teuchos::RCP<const MpiReductionOpBase>& reduct_op );

  ~MpiReductionOpSetter();

  MPI_Op mpi_op() const;
  
private:
  // Not defined and not to be called!
  MpiReductionOpSetter();
  MpiReductionOpSetter(const MpiReductionOpSetter&);
  MpiReductionOpSetter& operator=(const MpiReductionOpSetter&);
};

// ///////////////////////////////////////
// Template implemenations

template<typename Ordinal>
MpiReductionOp<Ordinal>::MpiReductionOp(
  const RCP<const ValueTypeReductionOp<Ordinal,char> > &reductOp
  )
  :reductOp_(reductOp)
{}

template<typename Ordinal>
void MpiReductionOp<Ordinal>::reduce(
  void              *invec
  ,void             *inoutvec
  ,int              *len
  ,MPI_Datatype     *datatype
  ) const
{
  (void)datatype;
#ifdef TEUCHOS_DEBUG
  TEST_FOR_EXCEPT(!invec);
  TEST_FOR_EXCEPT(!inoutvec);
  TEST_FOR_EXCEPT(!len);
  TEST_FOR_EXCEPT(!(*len>0));
  TEST_FOR_EXCEPT(!datatype);
  //TEST_FOR_EXCEPT(!(*datatype==MPI_CHAR));
  // We also allow datatypes that are blocks of chars!
#endif
  reductOp_->reduce(
    *len,reinterpret_cast<char*>(invec),reinterpret_cast<char*>(inoutvec)
    );
}

template<typename Ordinal>
RCP<const MpiReductionOp<Ordinal> >
mpiReductionOp( const RCP<const ValueTypeReductionOp<Ordinal,char> > &reductOp )
{
  return rcp(new MpiReductionOp<Ordinal>(reductOp));
}

} // namespace Teuchos

#endif // TEUCHOS_MPI_REDUCTION_OP_SETTER_HPP