OpenBLAS/kernel/arm64/symv_L_sve_v1x4.c

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#include "symv_microk_sve_v1x4.c"

int CNAME(BLASLONG m, BLASLONG offset, FLOAT alpha, FLOAT *a, BLASLONG lda,
          FLOAT *x, BLASLONG inc_x, FLOAT *y, BLASLONG inc_y, FLOAT *buffer)
{
  BLASLONG i, j;
  FLOAT temp1, temp2;
  FLOAT tmp1[4];
  FLOAT tmp2[4];
  FLOAT *a0, *a1, *a2, *a3;
  FLOAT x0, x1, x2, x3;
  FLOAT *X = x;
  FLOAT *Y = y;

  if (inc_y != 1) {
    Y = buffer;
    COPY_K(m, y, inc_y, Y, 1);
  }
  if (inc_x != 1) {
    if (inc_y != 1) {
      X = Y + m;
    } else {
      X = buffer;
    }
    COPY_K(m, x, inc_x, X, 1);
  }

  BLASLONG offset1 = (offset / 4) * 4;

  for (j = 0; j < offset1; j+=4) {
    a0 = &a[j*lda];
    a1 = a0 + lda;
    a2 = a1 + lda;
    a3 = a2 + lda;
    x0 = X[j];
    x1 = X[j+1];
    x2 = X[j+2];
    x3 = X[j+3];
    tmp2[0] = a0[j  ]*x0 + a0[j+1]*x1 + a0[j+2]*x2 + a0[j+3]*x3;
    tmp2[1] = a0[j+1]*x0 + a1[j+1]*x1 + a1[j+2]*x2 + a1[j+3]*x3;
    tmp2[2] = a0[j+2]*x0 + a1[j+2]*x1 + a2[j+2]*x2 + a2[j+3]*x3;
    tmp2[3] = a0[j+3]*x0 + a1[j+3]*x1 + a2[j+3]*x2 + a3[j+3]*x3;
    tmp1[0] = alpha * x0;
    tmp1[1] = alpha * x1;
    tmp1[2] = alpha * x2;
    tmp1[3] = alpha * x3;

    symv_kernel_v1x4(j+4, m, a0, a1, a2, a3, X, Y, tmp1, tmp2);

    Y[j]   += alpha * tmp2[0];
    Y[j+1] += alpha * tmp2[1];
    Y[j+2] += alpha * tmp2[2];
    Y[j+3] += alpha * tmp2[3];
  }

  for (j = offset1; j < offset; j++) {
    temp1 = alpha * X[j];
    temp2 = 0.0;
    a0 = &a[j*lda];
    Y[j] += temp1 * a0[j];
    for (i = j+1; i < m; i++) {
      Y[i] += temp1 * a0[i];
      temp2 += a0[i] * X[i];
    }
    Y[j] += alpha * temp2;
  }

  if (inc_y != 1) {
    COPY_K(m, Y, 1, y, inc_y);
  }
  return(0);
}