Exemple #1
0
void AllGather
( const DistMatrix<T,        U,           V   >& A,
        DistMatrix<T,Collect<U>(),Collect<V>()>& B )
{
    EL_DEBUG_CSE
    AssertSameGrids( A, B );

    const Int height = A.Height();
    const Int width = A.Width();
    B.SetGrid( A.Grid() );
    B.Resize( height, width );

    if( A.Participating() )
    {
        if( A.DistSize() == 1 )
        {
            Copy( A.LockedMatrix(), B.Matrix() );
        }
        else
        {
            const Int colStride = A.ColStride();
            const Int rowStride = A.RowStride();
            const Int distStride = colStride*rowStride;
            const Int maxLocalHeight = MaxLength(height,colStride);
            const Int maxLocalWidth = MaxLength(width,rowStride);
            const Int portionSize = mpi::Pad( maxLocalHeight*maxLocalWidth );
            vector<T> buf;
            FastResize( buf, (distStride+1)*portionSize );
            T* sendBuf = &buf[0];
            T* recvBuf = &buf[portionSize];

            // Pack
            util::InterleaveMatrix
            ( A.LocalHeight(), A.LocalWidth(),
              A.LockedBuffer(), 1, A.LDim(),
              sendBuf,          1, A.LocalHeight() );

            // Communicate
            mpi::AllGather
            ( sendBuf, portionSize, recvBuf, portionSize, A.DistComm() );

            // Unpack
            util::StridedUnpack
            ( height, width,
              A.ColAlign(), colStride,
              A.RowAlign(), rowStride,
              recvBuf, portionSize,
              B.Buffer(), B.LDim() );
        }
    }
    if( A.Grid().InGrid() && A.CrossComm() != mpi::COMM_SELF )
        El::Broadcast( B, A.CrossComm(), A.Root() );
}
Exemple #2
0
void TransposeDist( const DistMatrix<T,U,V>& A, DistMatrix<T,V,U>& B ) 
{
    DEBUG_ONLY(CSE cse("copy::TransposeDist"))
    AssertSameGrids( A, B );

    const Grid& g = B.Grid();
    B.Resize( A.Height(), A.Width() );
    if( !B.Participating() )
        return;

    const Int colStrideA = A.ColStride();
    const Int rowStrideA = A.RowStride();
    const Int distSize = A.DistSize();

    if( A.DistSize() == 1 && B.DistSize() == 1 ) 
    {
        Copy( A.LockedMatrix(), B.Matrix() );
    }
    else if( A.Width() == 1 )
    {
        const Int height = A.Height();
        const Int maxLocalHeight = MaxLength(height,distSize);
        const Int portionSize = mpi::Pad( maxLocalHeight );

        const Int colDiff = Shift(A.DistRank(),A.ColAlign(),distSize) - 
                            Shift(B.DistRank(),B.ColAlign(),distSize);
        const Int sendRankB = Mod( B.DistRank()+colDiff, distSize );
        const Int recvRankA = Mod( A.DistRank()-colDiff, distSize );
        const Int recvRankB = 
            (recvRankA/colStrideA)+rowStrideA*(recvRankA%colStrideA);

        vector<T> buffer;
        FastResize( buffer, (colStrideA+rowStrideA)*portionSize );
        T* sendBuf = &buffer[0];
        T* recvBuf = &buffer[colStrideA*portionSize];

        if( A.RowRank() == A.RowAlign() )
        {
            // Pack
            // TODO: Use kernel from copy::util
            const Int AColShift = A.ColShift();
            const T* ABuf = A.LockedBuffer();
            EL_PARALLEL_FOR
            for( Int k=0; k<rowStrideA; ++k )
            {
                T* data = &recvBuf[k*portionSize];

                const Int shift = 
                  Shift_(A.ColRank()+colStrideA*k,A.ColAlign(),distSize);
                const Int offset = (shift-AColShift) / colStrideA;
                const Int thisLocalHeight = Length_(height,shift,distSize);

                for( Int iLoc=0; iLoc<thisLocalHeight; ++iLoc )
                    data[iLoc] = ABuf[offset+iLoc*rowStrideA];
            }
        }

        // (e.g., A[VC,STAR] <- A[MC,MR])
        mpi::Scatter
        ( recvBuf, portionSize,
          sendBuf, portionSize, A.RowAlign(), A.RowComm() );

        // (e.g., A[VR,STAR] <- A[VC,STAR])
        mpi::SendRecv
        ( sendBuf, portionSize, sendRankB,
          recvBuf, portionSize, recvRankB, B.DistComm() );

        // (e.g., A[MR,MC] <- A[VR,STAR])
        mpi::Gather
        ( recvBuf, portionSize,
          sendBuf, portionSize, B.RowAlign(), B.RowComm() );

        if( B.RowRank() == B.RowAlign() )
        {
            // Unpack
            // TODO: Use kernel from copy::util
            T* bufB = B.Buffer();
            EL_PARALLEL_FOR
            for( Int k=0; k<colStrideA; ++k )
            {
                const T* data = &sendBuf[k*portionSize];

                const Int shift = 
                  Shift_(B.ColRank()+rowStrideA*k,B.ColAlign(),distSize);
                const Int offset = (shift-B.ColShift()) / rowStrideA;
                const Int thisLocalHeight = Length_(height,shift,distSize);

                for( Int iLoc=0; iLoc<thisLocalHeight; ++iLoc )
                    bufB[offset+iLoc*colStrideA] = data[iLoc];
            }
        }
    }