1
1
openmpi/ompi/mpi/fortran/use-mpi-f08/ialltoallw_f08.F90
Jeff Squyres 0acebc0a1f Make the Alltoall/Ialltoallw F08 interfaces a little less sucky.
Use proper array types for the sendtypes and recevtypes params in the
definition of these subroutines (since they're prototyped to be array
parameters in the module).  See the comment in the code for a more
complete explanation.

Note that after talking to Craig Rasumussen, he says that this is
fairly common practice in the Fortran community (i.e., pass a scalar
that is part of an array to effectively pass an offset into that
array, since Fortran passes by reference).  So this might be a hack,
but it's a commonly-accepted hack.

Reviewed by Craig Rasmussen.

cmr=v1.7.3:subject=Fix [I]Alltoallw mpi_f08 wrapper functions

This commit was SVN r29298.
2013-09-30 17:50:43 +00:00

39 строки
1.8 KiB
Fortran

! -*- f90 -*-
!
! Copyright (c) 2009-2013 Cisco Systems, Inc. All rights reserved.
! Copyright (c) 2009-2012 Los Alamos National Security, LLC.
! All rights reserved.
! $COPYRIGHT$
#include "ompi/mpi/fortran/configure-fortran-output.h"
subroutine MPI_Ialltoallw_f08(sendbuf,sendcounts,sdispls,sendtypes,&
recvbuf,recvcounts,rdispls,recvtypes,comm,request,ierror)
use :: mpi_f08_types, only : MPI_Datatype, MPI_Comm, MPI_Request
use :: mpi_f08, only : ompi_ialltoallw_f
implicit none
OMPI_FORTRAN_IGNORE_TKR_TYPE, INTENT(IN) :: sendbuf, recvbuf
INTEGER, INTENT(IN) :: sendcounts(*), sdispls(*), recvcounts(*), rdispls(*)
TYPE(MPI_Datatype), INTENT(IN) :: sendtypes(*)
TYPE(MPI_Datatype), INTENT(IN) :: recvtypes(*)
TYPE(MPI_Comm), INTENT(IN) :: comm
TYPE(MPI_Request), INTENT(OUT) :: request
INTEGER, OPTIONAL, INTENT(OUT) :: ierror
integer :: c_ierror
! Note that we pass a scalar here for both the sendtypes and
! recvtypes arguments, even though the real Alltoallw function
! expects an array of integers. This is a hack: we know that
! [send|recv]types(1)%MPI_VAL will pass the address of the first
! integer in the array of Type(MPI_Datatype) derived types. And
! since Type(MPI_Datatype) are exactly memory-equivalent to a
! single INTEGER, passing the address of the first one is the same
! as passing the address to an array of integers. To be clear: the
! back-end ompi_alltoallw_f is expecting a pointer to an array of
! integers. So it all works out (but is a hack :-\ ).
call ompi_ialltoallw_f(sendbuf,sendcounts,sdispls,sendtypes(1)%MPI_VAL,&
recvbuf,recvcounts,rdispls,recvtypes(1)%MPI_VAL,comm%MPI_VAL,request%MPI_VAL,c_ierror)
if (present(ierror)) ierror = c_ierror
end subroutine MPI_Ialltoallw_f08