Пример #1
0
/***************************************************************************//**
    Purpose
    -------
    SGELQF computes an LQ factorization of a REAL M-by-N matrix dA:
    dA = L * Q.

    Arguments
    ---------
    @param[in]
    m       INTEGER
            The number of rows of the matrix A.  M >= 0.

    @param[in]
    n       INTEGER
            The number of columns of the matrix A.  N >= 0.

    @param[in,out]
    dA      REAL array on the GPU, dimension (LDDA,N)
            On entry, the M-by-N matrix dA.
            On exit, the elements on and below the diagonal of the array
            contain the m-by-min(m,n) lower trapezoidal matrix L (L is
            lower triangular if m <= n); the elements above the diagonal,
            with the array TAU, represent the orthogonal matrix Q as a
            product of elementary reflectors (see Further Details).

    @param[in]
    ldda    INTEGER
            The leading dimension of the array dA.  LDDA >= max(1,M).

    @param[out]
    tau     REAL array, dimension (min(M,N))
            The scalar factors of the elementary reflectors (see Further
            Details).

    @param[out]
    work    (workspace) REAL array, dimension (MAX(1,LWORK))
            On exit, if INFO = 0, WORK[0] returns the optimal LWORK.
    \n
            Higher performance is achieved if WORK is in pinned memory, e.g.
            allocated using magma_malloc_pinned.

    @param[in]
    lwork   INTEGER
            The dimension of the array WORK.  LWORK >= max(1,M).
            For optimum performance LWORK >= M*NB, where NB is the
            optimal blocksize.
    \n
            If LWORK = -1, then a workspace query is assumed; the routine
            only calculates the optimal size of the WORK array, returns
            this value as the first entry of the WORK array, and no error
            message related to LWORK is issued.

    @param[out]
    info    INTEGER
      -     = 0:  successful exit
      -     < 0:  if INFO = -i, the i-th argument had an illegal value
                  or another error occured, such as memory allocation failed.

    Further Details
    ---------------
    The matrix Q is represented as a product of elementary reflectors

       Q = H(k) . . . H(2) H(1), where k = min(m,n).

    Each H(i) has the form

       H(i) = I - tau * v * v'

    where tau is a real scalar, and v is a real vector with
    v(1:i-1) = 0 and v(i) = 1; v(i+1:n) is stored on exit in A(i,i+1:n),
    and tau in TAU(i).

    @ingroup magma_gelqf
*******************************************************************************/
extern "C" magma_int_t
magma_sgelqf_gpu(
    magma_int_t m, magma_int_t n,
    magmaFloat_ptr dA, magma_int_t ldda,
    float *tau,
    float *work, magma_int_t lwork,
    magma_int_t *info)
{
    /* Constants */
    const float c_one = MAGMA_S_ONE;
    const magma_int_t ione = 1;
    MAGMA_UNUSED( ione );  // used only for real

    /* Local variables */
    magmaFloat_ptr dAT=NULL;
    magma_int_t min_mn, maxm, maxn, nb;
    magma_int_t iinfo;

    *info = 0;
    nb = magma_get_sgelqf_nb( m, n );
    min_mn = min( m, n );

    work[0] = magma_smake_lwork( m*nb );
    bool lquery = (lwork == -1);
    if (m < 0) {
        *info = -1;
    } else if (n < 0) {
        *info = -2;
    } else if (ldda < max(1,m)) {
        *info = -4;
    } else if (lwork < max(1,m) && ! lquery) {
        *info = -7;
    }
    if (*info != 0) {
        magma_xerbla( __func__, -(*info) );
        return *info;
    }
    else if (lquery) {
        return *info;
    }

    /*  Quick return if possible */
    if (min_mn == 0) {
        work[0] = c_one;
        return *info;
    }

    maxm = magma_roundup( m, 32 );
    maxn = magma_roundup( n, 32 );

    magma_int_t lddat = maxn;

    magma_queue_t queue;
    magma_device_t cdev;
    magma_getdevice( &cdev );
    magma_queue_create( cdev, &queue );
    
    if ( m == n ) {
        dAT = dA;
        lddat = ldda;
        magmablas_stranspose_inplace( m, dAT, ldda, queue );
    }
    else {
        if (MAGMA_SUCCESS != magma_smalloc( &dAT, maxm*maxn ) ) {
            *info = MAGMA_ERR_DEVICE_ALLOC;
            goto cleanup;
        }
        
        magmablas_stranspose( m, n, dA, ldda, dAT, lddat, queue );
    }
    
    magma_sgeqrf2_gpu( n, m, dAT, lddat, tau, &iinfo );
    assert( iinfo >= 0 );
    if ( iinfo > 0 ) {
        *info = iinfo;
    }
    
    // conjugate tau
    #ifdef COMPLEX
    lapackf77_slacgv( &min_mn, tau, &ione );
    #endif
    
    if ( m == n ) {
        magmablas_stranspose_inplace( m, dAT, lddat, queue );
    }
    else {
        magmablas_stranspose( n, m, dAT, lddat, dA, ldda, queue );
        magma_free( dAT );
    }

cleanup:
    magma_queue_destroy( queue );
    
    return *info;
} /* magma_sgelqf_gpu */
Пример #2
0
extern "C" magma_int_t
magma_sgelqf( magma_int_t m, magma_int_t n,
              float *a,    magma_int_t lda,   float *tau,
              float *work, magma_int_t lwork, magma_int_t *info)
{
/*  -- MAGMA (version 1.4.1) --
       Univ. of Tennessee, Knoxville
       Univ. of California, Berkeley
       Univ. of Colorado, Denver
       December 2013

    Purpose
    =======
    SGELQF computes an LQ factorization of a REAL M-by-N matrix A:
    A = L * Q.

    Arguments
    =========
    M       (input) INTEGER
            The number of rows of the matrix A.  M >= 0.

    N       (input) INTEGER
            The number of columns of the matrix A.  N >= 0.

    A       (input/output) REAL array, dimension (LDA,N)
            On entry, the M-by-N matrix A.
            On exit, the elements on and below the diagonal of the array
            contain the m-by-min(m,n) lower trapezoidal matrix L (L is
            lower triangular if m <= n); the elements above the diagonal,
            with the array TAU, represent the orthogonal matrix Q as a
            product of elementary reflectors (see Further Details).

            Higher performance is achieved if A is in pinned memory, e.g.
            allocated using magma_malloc_pinned.

    LDA     (input) INTEGER
            The leading dimension of the array A.  LDA >= max(1,M).

    TAU     (output) REAL array, dimension (min(M,N))
            The scalar factors of the elementary reflectors (see Further
            Details).

    WORK    (workspace/output) REAL array, dimension (MAX(1,LWORK))
            On exit, if INFO = 0, WORK(1) returns the optimal LWORK.

            Higher performance is achieved if WORK is in pinned memory, e.g.
            allocated using magma_malloc_pinned.

    LWORK   (input) INTEGER
            The dimension of the array WORK.  LWORK >= max(1,M).
            For optimum performance LWORK >= M*NB, where NB is the
            optimal blocksize.

            If LWORK = -1, then a workspace query is assumed; the routine
            only calculates the optimal size of the WORK array, returns
            this value as the first entry of the WORK array, and no error
            message related to LWORK is issued.

    INFO    (output) INTEGER
            = 0:  successful exit
            < 0:  if INFO = -i, the i-th argument had an illegal value
                  if INFO = -10 internal GPU memory allocation failed.

    Further Details
    ===============
    The matrix Q is represented as a product of elementary reflectors

       Q = H(k) . . . H(2) H(1), where k = min(m,n).

    Each H(i) has the form

       H(i) = I - tau * v * v'

    where tau is a real scalar, and v is a real vector with
    v(1:i-1) = 0 and v(i) = 1; v(i+1:n) is stored on exit in A(i,i+1:n),
    and tau in TAU(i).
    =====================================================================    */

    #define  a_ref(a_1,a_2) ( a+(a_2)*(lda) + (a_1))

    float *dA, *dAT;
    float c_one = MAGMA_S_ONE;
    magma_int_t maxm, maxn, maxdim, nb;
    magma_int_t iinfo, ldda;
    int lquery;

    /* Function Body */
    *info = 0;
    nb = magma_get_sgelqf_nb(m);

    work[0] = MAGMA_S_MAKE( (float)(m*nb), 0 );
    lquery = (lwork == -1);
    if (m < 0) {
        *info = -1;
    } else if (n < 0) {
        *info = -2;
    } else if (lda < max(1,m)) {
        *info = -4;
    } else if (lwork < max(1,m) && ! lquery) {
        *info = -7;
    }
    if (*info != 0) {
        magma_xerbla( __func__, -(*info) );
        return *info;
    }
    else if (lquery) {
        return *info;
    }

    /*  Quick return if possible */
    if (min(m, n) == 0) {
        work[0] = c_one;
        return *info;
    }

    maxm = ((m + 31)/32)*32;
    maxn = ((n + 31)/32)*32;
    maxdim = max(maxm, maxn);

    if (maxdim*maxdim < 2*maxm*maxn)
        {
            ldda = maxdim;

            if (MAGMA_SUCCESS != magma_smalloc( &dA, maxdim*maxdim )) {
                *info = MAGMA_ERR_DEVICE_ALLOC;
                return *info;
            }

            magma_ssetmatrix( m, n, a, lda, dA, ldda );
            dAT = dA;
            magmablas_stranspose_inplace( ldda, dAT, ldda );
        }
    else
        {
            ldda = maxn;

            if (MAGMA_SUCCESS != magma_smalloc( &dA, 2*maxn*maxm )) {
                *info = MAGMA_ERR_DEVICE_ALLOC;
                return *info;
            }

            magma_ssetmatrix( m, n, a, lda, dA, maxm );

            dAT = dA + maxn * maxm;
            magmablas_stranspose2( dAT, ldda, dA, maxm, m, n );
        }

    magma_sgeqrf2_gpu(n, m, dAT, ldda, tau, &iinfo);

    if (maxdim*maxdim < 2*maxm*maxn) {
        magmablas_stranspose_inplace( ldda, dAT, ldda );
        magma_sgetmatrix( m, n, dA, ldda, a, lda );
    } else {
        magmablas_stranspose2( dA, maxm, dAT, ldda, n, m );
        magma_sgetmatrix( m, n, dA, maxm, a, lda );
    }

    magma_free( dA );

    return *info;
} /* magma_sgelqf */
Пример #3
0
magma_int_t magmaf_get_sgelqf_nb( magma_int_t *m )
{
    return magma_get_sgelqf_nb( *m );
}
Пример #4
0
/**
    Purpose
    -------
    SORMQR overwrites the general real M-by-N matrix C with

    @verbatim
                              SIDE = MagmaLeft   SIDE = MagmaRight
    TRANS = MagmaNoTrans:     Q * C              C * Q
    TRANS = MagmaTrans:  Q**H * C           C * Q**H
    @endverbatim

    where Q is a real unitary matrix defined as the product of k
    elementary reflectors

        Q = H(1) H(2) . . . H(k)

    as returned by SGEQRF. Q is of order M if SIDE = MagmaLeft and of order N
    if SIDE = MagmaRight.

    Arguments
    ---------
    @param[in]
    side    magma_side_t
      -     = MagmaLeft:      apply Q or Q**H from the Left;
      -     = MagmaRight:     apply Q or Q**H from the Right.

    @param[in]
    trans   magma_trans_t
      -     = MagmaNoTrans:    No transpose, apply Q;
      -     = MagmaTrans: Conjugate transpose, apply Q**H.

    @param[in]
    m       INTEGER
            The number of rows of the matrix C. M >= 0.

    @param[in]
    n       INTEGER
            The number of columns of the matrix C. N >= 0.

    @param[in]
    k       INTEGER
            The number of elementary reflectors whose product defines
            the matrix Q.
            If SIDE = MagmaLeft,  M >= K >= 0;
            if SIDE = MagmaRight, N >= K >= 0.

    @param[in]
    A       REAL array, dimension (LDA,K)
            The i-th column must contain the vector which defines the
            elementary reflector H(i), for i = 1,2,...,k, as returned by
            SGEQRF in the first k columns of its array argument A.
            A is modified by the routine but restored on exit.

    @param[in]
    lda     INTEGER
            The leading dimension of the array A.
            If SIDE = MagmaLeft,  LDA >= max(1,M);
            if SIDE = MagmaRight, LDA >= max(1,N).

    @param[in]
    tau     REAL array, dimension (K)
            TAU(i) must contain the scalar factor of the elementary
            reflector H(i), as returned by SGEQRF.

    @param[in,out]
    C       REAL array, dimension (LDC,N)
            On entry, the M-by-N matrix C.
            On exit, C is overwritten by Q*C or Q**H * C or C * Q**H or C*Q.

    @param[in]
    ldc     INTEGER
            The leading dimension of the array C. LDC >= max(1,M).

    @param[out]
    work    (workspace) REAL array, dimension (MAX(1,LWORK))
            On exit, if INFO = 0, WORK[0] returns the optimal LWORK.

    @param[in]
    lwork   INTEGER
            The dimension of the array WORK.
            If SIDE = MagmaLeft,  LWORK >= max(1,N);
            if SIDE = MagmaRight, LWORK >= max(1,M).
            For optimum performance
            if SIDE = MagmaLeft,  LWORK >= N*NB;
            if SIDE = MagmaRight, LWORK >= M*NB,
            where NB is the optimal blocksize.
    \n
            If LWORK = -1, then a workspace query is assumed; the routine
            only calculates the optimal size of the WORK array, returns
            this value as the first entry of the WORK array, and no error
            message related to LWORK is issued by XERBLA.

    @param[out]
    info    INTEGER
      -     = 0:  successful exit
      -     < 0:  if INFO = -i, the i-th argument had an illegal value

    @ingroup magma_sgeqrf_comp
    ********************************************************************/
extern "C" magma_int_t
magma_sormqr(
    magma_side_t side, magma_trans_t trans,
    magma_int_t m, magma_int_t n, magma_int_t k,
    float *A,    magma_int_t lda,
    float *tau,
    float *C,    magma_int_t ldc,
    float *work, magma_int_t lwork,
    magma_int_t *info)
{
    #define  A(i_,j_) ( A + (i_) + (j_)*lda)
    #define dC(i_,j_) (dC + (i_) + (j_)*lddc)
    
    float *T, *T2;
    magma_int_t i, i1, i2, ib, ic, jc, nb, mi, ni, nq, nq_i, nw, step;
    magma_int_t iinfo, ldwork, lwkopt;
    magma_int_t left, notran, lquery;

    *info = 0;
    left   = (side == MagmaLeft);
    notran = (trans == MagmaNoTrans);
    lquery = (lwork == -1);

    /* NQ is the order of Q and NW is the minimum dimension of WORK */
    if (left) {
        nq = m;
        nw = n;
    } else {
        nq = n;
        nw = m;
    }
    
    /* Test the input arguments */
    if (! left && side != MagmaRight) {
        *info = -1;
    } else if (! notran && trans != MagmaTrans) {
        *info = -2;
    } else if (m < 0) {
        *info = -3;
    } else if (n < 0) {
        *info = -4;
    } else if (k < 0 || k > nq) {
        *info = -5;
    } else if (lda < max(1,nq)) {
        *info = -7;
    } else if (ldc < max(1,m)) {
        *info = -10;
    } else if (lwork < max(1,nw) && ! lquery) {
        *info = -12;
    }

    if (*info == 0) {
        nb = magma_get_sgelqf_nb( min( m, n ));
        lwkopt = max(1,nw)*nb;
        work[0] = MAGMA_S_MAKE( lwkopt, 0 );
    }

    if (*info != 0) {
        magma_xerbla( __func__, -(*info) );
        return *info;
    }
    else if (lquery) {
        return *info;
    }

    /* Quick return if possible */
    if (m == 0 || n == 0 || k == 0) {
        work[0] = MAGMA_S_ONE;
        return *info;
    }

    ldwork = nw;

    if (nb >= k) {
        /* Use CPU code */
        lapackf77_sormqr( lapack_side_const(side), lapack_trans_const(trans),
            &m, &n, &k, A, &lda, tau, C, &ldc, work, &lwork, &iinfo);
    }
    else {
        /* Use hybrid CPU-GPU code */
        /* Allocate work space on the GPU.
         * nw*nb  for dwork (m or n) by nb
         * nq*nb  for dV    (n or m) by nb
         * nb*nb  for dT
         * lddc*n for dC.
         */
        magma_int_t lddc = ((m+31)/32)*32;
        float *dwork, *dV, *dT, *dC;
        magma_smalloc( &dwork, (nw + nq + nb)*nb + lddc*n );
        if ( dwork == NULL ) {
            *info = MAGMA_ERR_DEVICE_ALLOC;
            return *info;
        }
        dV = dwork + nw*nb;
        dT = dV    + nq*nb;
        dC = dT    + nb*nb;
        
        /* work space on CPU.
         * nb*nb for T
         * nb*nb for T2, used to save and restore diagonal block of panel */
        magma_smalloc_cpu( &T, 2*nb*nb );
        if ( T == NULL ) {
            magma_free( dwork );
            *info = MAGMA_ERR_HOST_ALLOC;
            return *info;
        }
        T2 = T + nb*nb;
        
        /* Copy matrix C from the CPU to the GPU */
        magma_ssetmatrix( m, n, C, ldc, dC, lddc );
        
        if ( (left && ! notran) ||  (! left && notran) ) {
            i1 = 0;
            i2 = k;
            step = nb;
        } else {
            i1 = ((k - 1) / nb) * nb;
            i2 = 0;
            step = -nb;
        }

        // silence "uninitialized" warnings
        mi = 0;
        ni = 0;
        
        if (left) {
            ni = n;
            jc = 0;
        } else {
            mi = m;
            ic = 0;
        }
        
        for (i = i1; (step < 0 ? i >= i2 : i < i2); i += step) {
            ib = min(nb, k - i);

            /* Form the triangular factor of the block reflector
               H = H(i) H(i+1) . . . H(i+ib-1) */
            nq_i = nq - i;
            lapackf77_slarft("Forward", "Columnwise", &nq_i, &ib,
                             A(i,i), &lda, &tau[i], T, &ib);

            /* 1) set upper triangle of panel in A to identity,
               2) copy the panel from A to the GPU, and
               3) restore A                                      */
            spanel_to_q( MagmaUpper, ib, A(i,i), lda, T2 );
            magma_ssetmatrix( nq_i,  ib, A(i,i), lda, dV, nq_i );
            sq_to_panel( MagmaUpper, ib, A(i,i), lda, T2 );

            if (left) {
                /* H or H**H is applied to C(i:m,1:n) */
                mi = m - i;
                ic = i;
            }
            else {
                /* H or H**H is applied to C(1:m,i:n) */
                ni = n - i;
                jc = i;
            }

            /* Apply H or H**H; First copy T to the GPU */
            magma_ssetmatrix( ib, ib, T, ib, dT, ib );
            magma_slarfb_gpu( side, trans, MagmaForward, MagmaColumnwise,
                              mi, ni, ib,
                              dV, nq_i,
                              dT, ib,
                              dC(ic,jc), lddc,
                              dwork, ldwork );
        }
        magma_sgetmatrix( m, n, dC, lddc, C, ldc );

        magma_free( dwork );
        magma_free_cpu( T );
    }
    work[0] = MAGMA_S_MAKE( lwkopt, 0 );

    return *info;
} /* magma_sormqr */
Пример #5
0
/***************************************************************************//**
    Purpose
    -------
    SGELQF computes an LQ factorization of a REAL M-by-N matrix A:
    A = L * Q.

    Arguments
    ---------
    @param[in]
    m       INTEGER
            The number of rows of the matrix A.  M >= 0.

    @param[in]
    n       INTEGER
            The number of columns of the matrix A.  N >= 0.

    @param[in,out]
    A       REAL array, dimension (LDA,N)
            On entry, the M-by-N matrix A.
            On exit, the elements on and below the diagonal of the array
            contain the m-by-min(m,n) lower trapezoidal matrix L (L is
            lower triangular if m <= n); the elements above the diagonal,
            with the array TAU, represent the orthogonal matrix Q as a
            product of elementary reflectors (see Further Details).
    \n
            Higher performance is achieved if A is in pinned memory, e.g.
            allocated using magma_malloc_pinned.

    @param[in]
    lda     INTEGER
            The leading dimension of the array A.  LDA >= max(1,M).

    @param[out]
    tau     REAL array, dimension (min(M,N))
            The scalar factors of the elementary reflectors (see Further
            Details).

    @param[out]
    work    (workspace) REAL array, dimension (MAX(1,LWORK))
            On exit, if INFO = 0, WORK[0] returns the optimal LWORK.

    @param[in]
    lwork   INTEGER
            The dimension of the array WORK.  LWORK >= max(1,M).
            For optimum performance LWORK >= M*NB, where NB is the
            optimal blocksize.
    \n
            If LWORK = -1, then a workspace query is assumed; the routine
            only calculates the optimal size of the WORK array, returns
            this value as the first entry of the WORK array, and no error
            message related to LWORK is issued.
    \n
            TODO: work is currently unused. sgeqrf2 allocates its own work of (m + n)*nb.

    @param[out]
    info    INTEGER
      -     = 0:  successful exit
      -     < 0:  if INFO = -i, the i-th argument had an illegal value
                  or another error occured, such as memory allocation failed.

    Further Details
    ---------------
    The matrix Q is represented as a product of elementary reflectors

       Q = H(k) . . . H(2) H(1), where k = min(m,n).

    Each H(i) has the form

       H(i) = I - tau * v * v'

    where tau is a real scalar, and v is a real vector with
    v(1:i-1) = 0 and v(i) = 1; v(i+1:n) is stored on exit in A(i,i+1:n),
    and tau in TAU(i).

    @ingroup magma_gelqf
*******************************************************************************/
extern "C" magma_int_t
magma_sgelqf(
    magma_int_t m, magma_int_t n,
    float *A,    magma_int_t lda,   float *tau,
    float *work, magma_int_t lwork,
    magma_int_t *info)
{
    #define  dA(i_, j_)  (dA  + (i_) + (j_)*ldda)
    #define dAT(i_, j_)  (dAT + (i_) + (j_)*ldda)
    
    /* Constants */
    const float c_one = MAGMA_S_ONE;
    const magma_int_t ione = 1;
    MAGMA_UNUSED( ione );  // used only for real
    
    /* Local variables */
    magmaFloat_ptr dA=NULL, dAT=NULL;
    magma_int_t min_mn, maxm, maxn, maxdim, nb;
    magma_int_t iinfo, ldda, lddat;

    /* Function Body */
    *info = 0;
    nb = magma_get_sgelqf_nb( m, n );
    min_mn = min( m, n );

    work[0] = magma_smake_lwork( m*nb );
    bool lquery = (lwork == -1);
    if (m < 0) {
        *info = -1;
    } else if (n < 0) {
        *info = -2;
    } else if (lda < max(1,m)) {
        *info = -4;
    } else if (lwork < max(1,m) && ! lquery) {
        *info = -7;
    }
    if (*info != 0) {
        magma_xerbla( __func__, -(*info) );
        return *info;
    }
    else if (lquery) {
        return *info;
    }

    /* Quick return if possible */
    if (min_mn == 0) {
        work[0] = c_one;
        return *info;
    }

    maxm = magma_roundup( m, 32 );
    maxn = magma_roundup( n, 32 );
    maxdim = max( maxm, maxn );

    magma_queue_t queue = NULL;
    magma_device_t cdev;
    magma_getdevice( &cdev );
    magma_queue_create( cdev, &queue );
    
    // copy to GPU and transpose
    if (maxdim*maxdim < 2*maxm*maxn) {
        // close to square, do everything in-place
        ldda  = maxdim;
        lddat = maxdim;

        if (MAGMA_SUCCESS != magma_smalloc( &dA, maxdim*maxdim )) {
            *info = MAGMA_ERR_DEVICE_ALLOC;
            goto cleanup;
        }

        magma_ssetmatrix( m, n, A, lda, dA(0,0), ldda, queue );
        dAT = dA;
        magmablas_stranspose_inplace( lddat, dAT(0,0), lddat, queue );
    }
    else {
        // rectangular, do everything out-of-place
        ldda  = maxm;
        lddat = maxn;

        if (MAGMA_SUCCESS != magma_smalloc( &dA, 2*maxn*maxm )) {
            *info = MAGMA_ERR_DEVICE_ALLOC;
            goto cleanup;
        }

        magma_ssetmatrix( m, n, A, lda, dA(0,0), ldda, queue );

        dAT = dA + maxn * maxm;
        magmablas_stranspose( m, n, dA(0,0), ldda, dAT(0,0), lddat, queue );
    }

    // factor QR
    magma_sgeqrf2_gpu( n, m, dAT(0,0), lddat, tau, &iinfo );
    assert( iinfo >= 0 );
    if ( iinfo > 0 ) {
        *info = iinfo;
    }
    
    // conjugate tau
    #ifdef COMPLEX
    lapackf77_slacgv( &min_mn, tau, &ione );
    #endif

    // undo transpose
    if (maxdim*maxdim < 2*maxm*maxn) {
        magmablas_stranspose_inplace( lddat, dAT(0,0), lddat, queue );
        magma_sgetmatrix( m, n, dA(0,0), ldda, A, lda, queue );
    } else {
        magmablas_stranspose( n, m, dAT(0,0), lddat, dA(0,0), ldda, queue );
        magma_sgetmatrix( m, n, dA(0,0), ldda, A, lda, queue );
    }

cleanup:
    magma_queue_destroy( queue );
    magma_free( dA );

    return *info;
} /* magma_sgelqf */