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*****************************************************************************
* Contents: Native middle-level C interface to LAPACK function slarft
* Author: Intel Corporation
*****************************************************************************/

#include "lapacke_utils.h"

lapack_int LAPACKE_slarft_work( int matrix_layout, char direct, char storev,
                                lapack_int n, lapack_int k, const float* v,
                                lapack_int ldv, const float* tau, float* t,
                                lapack_int ldt )
{
    lapack_int info = 0;
    lapack_int nrows_v, ncols_v;
    lapack_int ldt_t, ldv_t;
    float *v_t = NULL, *t_t = NULL;
    if( matrix_layout == LAPACK_COL_MAJOR ) {
        /* Call LAPACK function and adjust info */
        LAPACK_slarft( &direct, &storev, &n, &k, v, &ldv, tau, t, &ldt );
        if( info < 0 ) {
            info = info - 1;
        }
    } else if( matrix_layout == LAPACK_ROW_MAJOR ) {
        nrows_v = LAPACKE_lsame( storev, 'c' ) ? n :
                             ( LAPACKE_lsame( storev, 'r' ) ? k : 1);
        ncols_v = LAPACKE_lsame( storev, 'c' ) ? k :
                             ( LAPACKE_lsame( storev, 'r' ) ? n : 1);
        ldt_t = MAX(1,k);
        ldv_t = MAX(1,nrows_v);
        /* Check leading dimension(s) */
        if( ldt < k ) {
            info = -10;
            LAPACKE_xerbla( "LAPACKE_slarft_work", info );
            return info;
        }
        if( ldv < ncols_v ) {
            info = -7;
            LAPACKE_xerbla( "LAPACKE_slarft_work", info );
            return info;
        }
        /* Allocate memory for temporary array(s) */
        v_t = (float*)LAPACKE_malloc( sizeof(float) * ldv_t * MAX(1,ncols_v) );
        if( v_t == NULL ) {
            info = LAPACK_TRANSPOSE_MEMORY_ERROR;
            goto exit_level_0;
        }
        t_t = (float*)LAPACKE_malloc( sizeof(float) * ldt_t * MAX(1,k) );
        if( t_t == NULL ) {
            info = LAPACK_TRANSPOSE_MEMORY_ERROR;
            goto exit_level_1;
        }
        /* Transpose input matrices */
        LAPACKE_sge_trans( matrix_layout, nrows_v, ncols_v, v, ldv, v_t, ldv_t );
        /* Call LAPACK function and adjust info */
        LAPACK_slarft( &direct, &storev, &n, &k, v_t, &ldv_t, tau, t_t,
                       &ldt_t );
        info = 0;  /* LAPACK call is ok! */
        /* Transpose output matrices */
        LAPACKE_sge_trans( LAPACK_COL_MAJOR, k, k, t_t, ldt_t, t, ldt );
        /* Release memory and exit */
        LAPACKE_free( t_t );
exit_level_1:
        LAPACKE_free( v_t );
exit_level_0:
        if( info == LAPACK_TRANSPOSE_MEMORY_ERROR ) {
            LAPACKE_xerbla( "LAPACKE_slarft_work", info );
        }
    } else {
        info = -1;
        LAPACKE_xerbla( "LAPACKE_slarft_work", info );
    }
    return info;
}
