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

#include "lapacke_utils.h"

lapack_int LAPACKE_zggev_work( int matrix_layout, char jobvl, char jobvr,
                               lapack_int n, lapack_complex_double* a,
                               lapack_int lda, lapack_complex_double* b,
                               lapack_int ldb, lapack_complex_double* alpha,
                               lapack_complex_double* beta,
                               lapack_complex_double* vl, lapack_int ldvl,
                               lapack_complex_double* vr, lapack_int ldvr,
                               lapack_complex_double* work, lapack_int lwork,
                               double* rwork )
{
    lapack_int info = 0;
    if( matrix_layout == LAPACK_COL_MAJOR ) {
        /* Call LAPACK function and adjust info */
        LAPACK_zggev( &jobvl, &jobvr, &n, a, &lda, b, &ldb, alpha, beta, vl,
                      &ldvl, vr, &ldvr, work, &lwork, rwork, &info );
        if( info < 0 ) {
            info = info - 1;
        }
    } else if( matrix_layout == LAPACK_ROW_MAJOR ) {
        lapack_int nrows_vl = LAPACKE_lsame( jobvl, 'v' ) ? n : 1;
        lapack_int ncols_vl = LAPACKE_lsame( jobvl, 'v' ) ? n : 1;
        lapack_int nrows_vr = LAPACKE_lsame( jobvr, 'v' ) ? n : 1;
        lapack_int ncols_vr = LAPACKE_lsame( jobvr, 'v' ) ? n : 1;
        lapack_int lda_t = MAX(1,n);
        lapack_int ldb_t = MAX(1,n);
        lapack_int ldvl_t = MAX(1,nrows_vl);
        lapack_int ldvr_t = MAX(1,nrows_vr);
        lapack_complex_double* a_t = NULL;
        lapack_complex_double* b_t = NULL;
        lapack_complex_double* vl_t = NULL;
        lapack_complex_double* vr_t = NULL;
        /* Check leading dimension(s) */
        if( lda < n ) {
            info = -6;
            LAPACKE_xerbla( "LAPACKE_zggev_work", info );
            return info;
        }
        if( ldb < n ) {
            info = -8;
            LAPACKE_xerbla( "LAPACKE_zggev_work", info );
            return info;
        }
        if( ldvl < ncols_vl ) {
            info = -12;
            LAPACKE_xerbla( "LAPACKE_zggev_work", info );
            return info;
        }
        if( ldvr < ncols_vr ) {
            info = -14;
            LAPACKE_xerbla( "LAPACKE_zggev_work", info );
            return info;
        }
        /* Query optimal working array(s) size if requested */
        if( lwork == -1 ) {
            LAPACK_zggev( &jobvl, &jobvr, &n, a, &lda_t, b, &ldb_t, alpha, beta,
                          vl, &ldvl_t, vr, &ldvr_t, work, &lwork, rwork,
                          &info );
            return (info < 0) ? (info - 1) : info;
        }
        /* Allocate memory for temporary array(s) */
        a_t = (lapack_complex_double*)
            LAPACKE_malloc( sizeof(lapack_complex_double) * lda_t * MAX(1,n) );
        if( a_t == NULL ) {
            info = LAPACK_TRANSPOSE_MEMORY_ERROR;
            goto exit_level_0;
        }
        b_t = (lapack_complex_double*)
            LAPACKE_malloc( sizeof(lapack_complex_double) * ldb_t * MAX(1,n) );
        if( b_t == NULL ) {
            info = LAPACK_TRANSPOSE_MEMORY_ERROR;
            goto exit_level_1;
        }
        if( LAPACKE_lsame( jobvl, 'v' ) ) {
            vl_t = (lapack_complex_double*)
                LAPACKE_malloc( sizeof(lapack_complex_double) *
                                ldvl_t * MAX(1,ncols_vl) );
            if( vl_t == NULL ) {
                info = LAPACK_TRANSPOSE_MEMORY_ERROR;
                goto exit_level_2;
            }
        }
        if( LAPACKE_lsame( jobvr, 'v' ) ) {
            vr_t = (lapack_complex_double*)
                LAPACKE_malloc( sizeof(lapack_complex_double) *
                                ldvr_t * MAX(1,ncols_vr) );
            if( vr_t == NULL ) {
                info = LAPACK_TRANSPOSE_MEMORY_ERROR;
                goto exit_level_3;
            }
        }
        /* Transpose input matrices */
        LAPACKE_zge_trans( matrix_layout, n, n, a, lda, a_t, lda_t );
        LAPACKE_zge_trans( matrix_layout, n, n, b, ldb, b_t, ldb_t );
        /* Call LAPACK function and adjust info */
        LAPACK_zggev( &jobvl, &jobvr, &n, a_t, &lda_t, b_t, &ldb_t, alpha, beta,
                      vl_t, &ldvl_t, vr_t, &ldvr_t, work, &lwork, rwork,
                      &info );
        if( info < 0 ) {
            info = info - 1;
        }
        /* Transpose output matrices */
        LAPACKE_zge_trans( LAPACK_COL_MAJOR, n, n, a_t, lda_t, a, lda );
        LAPACKE_zge_trans( LAPACK_COL_MAJOR, n, n, b_t, ldb_t, b, ldb );
        if( LAPACKE_lsame( jobvl, 'v' ) ) {
            LAPACKE_zge_trans( LAPACK_COL_MAJOR, nrows_vl, ncols_vl, vl_t,
                               ldvl_t, vl, ldvl );
        }
        if( LAPACKE_lsame( jobvr, 'v' ) ) {
            LAPACKE_zge_trans( LAPACK_COL_MAJOR, nrows_vr, ncols_vr, vr_t,
                               ldvr_t, vr, ldvr );
        }
        /* Release memory and exit */
        if( LAPACKE_lsame( jobvr, 'v' ) ) {
            LAPACKE_free( vr_t );
        }
exit_level_3:
        if( LAPACKE_lsame( jobvl, 'v' ) ) {
            LAPACKE_free( vl_t );
        }
exit_level_2:
        LAPACKE_free( b_t );
exit_level_1:
        LAPACKE_free( a_t );
exit_level_0:
        if( info == LAPACK_TRANSPOSE_MEMORY_ERROR ) {
            LAPACKE_xerbla( "LAPACKE_zggev_work", info );
        }
    } else {
        info = -1;
        LAPACKE_xerbla( "LAPACKE_zggev_work", info );
    }
    return info;
}
