OpenBLAS/kernel/arm64/symv_U_asimd_4x4.c

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#include "symv_microk_asimd_4x4.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, j1, j2, m2;
  FLOAT temp1, temp2;
  FLOAT tmp1[4];
  FLOAT tmp2[4];
  FLOAT *a0, *a1, *a2, *a3;
  FLOAT *X = x;
  FLOAT *Y = y;

  BLASLONG m1 = m - offset;
  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);
  }

  m2 = m - (offset % 4);
  for (j = m1; j < m2; j += 4) {
    tmp1[0] = alpha * X[j];
    tmp1[1] = alpha * X[j+1];
    tmp1[2] = alpha * X[j+2];
    tmp1[3] = alpha * X[j+3];
    tmp2[0] = 0.0;
    tmp2[1] = 0.0;
    tmp2[2] = 0.0;
    tmp2[3] = 0.0;
    a0 = &a[j*lda];
    a1 = a0 + lda;
    a2 = a1 + lda;
    a3 = a2 + lda;
    j1 = (j / 4) * 4;
    if ( j1 )
      symv_kernel_4x4(0, j1, a0, a1, a2, a3, X, Y, tmp1, tmp2);

    j2 = 0;
    for (j1 = j ; j1 < j+4 ; j1++) {
      temp1 = tmp1[j2];
      temp2 = tmp2[j2];
      a0 = &a[j1*lda];
      for (i=j ; i<j1; i++) {
        Y[i] += temp1 * a0[i];
        temp2 += a0[i] * X[i];
      }
      Y[j1] += temp1 * a0[j1] + alpha * temp2;
      j2++;
    }
  }

  for ( ; j < m; j++) {
    temp1 = alpha * X[j];
    temp2 = 0.0;
    a0 = &a[j*lda];
    for (i = 0 ; i < j; i++) {
      Y[i] += temp1 * a0[i];
      temp2 += a0[i] * X[i];
    }
    Y[j] += temp1 * a0[j] + alpha * temp2;
  }

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