core_sttqrt.c

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#include <lapacke.h>
#include "common.h"
#undef COMPLEX
#define REAL

/***************************************************************************/
#if defined(PLASMA_HAVE_WEAK)
#pragma weak CORE_sttqrt = PCORE_sttqrt
#define CORE_sttqrt PCORE_sttqrt
#endif
int CORE_sttqrt(int M, int N, int IB,
                float *A1, int LDA1,
                float *A2, int LDA2,
                float *T, int LDT,
                float *TAU, float *WORK)
{
    static int                ione  = 1;
    static float zone  = 1.0;
    static float zzero = 0.0;

    float alpha;
    int i, j, l, ii, sb, mi, ni;

    /* Check input arguments */
    if (M < 0) {
        coreblas_error(1, "Illegal value of M");
        return -1;
    }
    if (N < 0) {
        coreblas_error(2, "Illegal value of N");
        return -2;
    }
    if (IB < 0) {
        coreblas_error(3, "Illegal value of IB");
        return -3;
    }
    if ((LDA2 < max(1,M)) && (M > 0)) {
        coreblas_error(7, "Illegal value of LDA2");
        return -7;
    }

    /* Quick return */
    if ((M == 0) || (N == 0) || (IB == 0))
        return PLASMA_SUCCESS;

    /* TODO: Need to check why some cases require 
     *  this to not have uninitialized values */
    CORE_slaset( PlasmaUpperLower, IB, N,
                 0., 0., T, LDT);

    for (ii = 0; ii < N; ii += IB) {
        sb = min(N-ii, IB);
        for (i = 0; i < sb; i++) {
            j  = ii + i;
            mi = min( j + 1, M );
            ni = sb-i-1;

            /*
             * Generate elementary reflector H( II*IB+I ) to annihilate
             * A( II*IB+I:mi, II*IB+I ).
             */
            LAPACKE_slarfg_work(
                    mi+1, &A1[LDA1*j+j], &A2[LDA2*j], ione, &TAU[j]);

            if (ni > 0) {
                /*
                 * Apply H( II*IB+I ) to A( II*IB+I:M, II*IB+I+1:II*IB+IB ) from the left.
                 */
                cblas_scopy(
                    ni,
                    &A1[LDA1*(j+1)+j], LDA1,
                    WORK, 1);

#ifdef COMPLEX
                LAPACKE_slacgv_work(ni, WORK, 1);
#endif
                cblas_sgemv(
                    CblasColMajor, (CBLAS_TRANSPOSE)PlasmaTrans,
                    mi, ni,
                    (zone), &A2[LDA2*(j+1)], LDA2,
                                       &A2[LDA2*j],     1,
                    (zone), WORK,            1);
#ifdef COMPLEX
                LAPACKE_slacgv_work(ni, WORK, 1);
#endif
                alpha = -(TAU[j]);
                cblas_saxpy(
                    ni, (alpha),
                    WORK, 1,
                    &A1[LDA1*(j+1)+j], LDA1);
#ifdef COMPLEX
                LAPACKE_slacgv_work(ni, WORK, 1);
#endif
                cblas_sger(
                    CblasColMajor, mi, ni,
                    (alpha), &A2[LDA2*j], 1,
                    WORK, 1,
                    &A2[LDA2*(j+1)], LDA2);
            }

            /*
             * Calculate T
             *
             * T(0:i-1, j) = alpha * A2(0:M-1, ii:j-1)' * A2(0:M-1, j)
             */

            if ( i > 0 ) {

                l = min(i, max(0, M-ii));
                alpha = -(TAU[j]);

                CORE_spemv(
                        PlasmaTrans, PlasmaColumnwise,
                        min(j, M), i, l,
                        alpha, &A2[LDA2*ii], LDA2,
                               &A2[LDA2*j],  1,
                        zzero, &T[LDT*j],    1,
                        WORK);

                /* T(0:i-1, j) = T(0:i-1, ii:j-1) * T(0:i-1, j) */
                cblas_strmv(
                        CblasColMajor, (CBLAS_UPLO)PlasmaUpper,
                        (CBLAS_TRANSPOSE)PlasmaNoTrans,
                        (CBLAS_DIAG)PlasmaNonUnit,
                        i, &T[LDT*ii], LDT,
                           &T[LDT*j], 1);

            }

            T[LDT*j+i] = TAU[j];
        }

        /* Apply Q' to the rest of the matrix to the left  */
        if (N > ii+sb) {
            mi = min(ii+sb, M);
            ni = N-(ii+sb);
            l  = min(sb, max(0, mi-ii));
            CORE_sparfb(
                PlasmaLeft, PlasmaTrans,
                PlasmaForward, PlasmaColumnwise,
                IB, ni, mi, ni, sb, l,             //replaced sb by IB
                &A1[LDA1*(ii+sb)+ii], LDA1,
                &A2[LDA2*(ii+sb)], LDA2,
                &A2[LDA2*ii], LDA2,
                &T[LDT*ii], LDT,
                WORK, sb);
        }
    }
    return PLASMA_SUCCESS;
}

/***************************************************************************/
void QUARK_CORE_sttqrt(Quark *quark, Quark_Task_Flags *task_flags,
                       int m, int n, int ib, int nb,
                       float *A1, int lda1,
                       float *A2, int lda2,
                       float *T, int ldt)
{
    DAG_CORE_TTQRT;
    QUARK_Insert_Task(quark, CORE_sttqrt_quark, task_flags,
        sizeof(int),                        &m,     VALUE,
        sizeof(int),                        &n,     VALUE,
        sizeof(int),                        &ib,    VALUE,
        sizeof(float)*nb*nb,    A1,            INOUT|QUARK_REGION_D|QUARK_REGION_U,
        sizeof(int),                        &lda1,  VALUE,
        sizeof(float)*nb*nb,    A2,            INOUT|QUARK_REGION_D|QUARK_REGION_U|LOCALITY,
        sizeof(int),                        &lda2,  VALUE,
        sizeof(float)*ib*nb,    T,             OUTPUT,
        sizeof(int),                        &ldt,   VALUE,
        sizeof(float)*nb,       NULL,          SCRATCH,
        sizeof(float)*ib*nb,    NULL,          SCRATCH,
        0);
}

/***************************************************************************/
#if defined(PLASMA_HAVE_WEAK)
#pragma weak CORE_sttqrt_quark = PCORE_sttqrt_quark
#define CORE_sttqrt_quark PCORE_sttqrt_quark
#endif
void CORE_sttqrt_quark(Quark *quark)
{
    int m;
    int n;
    int ib;
    float *A1;
    int lda1;
    float *A2;
    int lda2;
    float *T;
    int ldt;
    float *TAU;
    float *WORK;

    quark_unpack_args_11(quark, m, n, ib, A1, lda1, A2, lda2, T, ldt, TAU, WORK);
    CORE_sttqrt(m, n, ib, A1, lda1, A2, lda2, T, ldt, TAU, WORK);
}