Function indexFromValue

Src/Base/AMReX_MultiFab.cpp:982–1008

namespace {

IntVect
indexFromValue (MultiFab const& mf, int comp, int nghost, Real value, MPI_Op mmloc)
{
    IntVect loc = indexFromValue(mf, comp, IntVect{nghost}, value);

#ifdef BL_USE_MPI
    const int NProcs = ParallelContext::NProcsSub();
    if (NProcs > 1)
    {
        struct {
            Real mm;
            int rank;
        } in, out;
        in.mm = value;
        in.rank = ParallelContext::MyProcSub();
        MPI_Datatype datatype = (sizeof(Real) == sizeof(double))
            ? MPI_DOUBLE_INT : MPI_FLOAT_INT;
        MPI_Comm comm = ParallelContext::CommunicatorSub();
        MPI_Allreduce(&in,  &out, 1, datatype, mmloc, comm);
        MPI_Bcast(&(loc[0]), AMREX_SPACEDIM, MPI_INT, out.rank, comm);
    }
#else
    amrex::ignore_unused(mmloc);
#endif

    return loc;
}

}