vmv.s.x

{
  let SEW      = get_sew();
  let num_elem = get_num_elem(0, SEW);

  if illegal_vd_unmasked() then { handle_illegal(); return RETIRE_FAIL };

  assert(num_elem > 0);
  let 'n = num_elem;
  let 'm = SEW;

  let vm_val  : vector('n, dec, bool)     = read_vmask(num_elem, 0b1, 0b00000);
  let rs1_val : bits('m)                  = get_scalar(rs1, 'm);
  let vd_val  : vector('n, dec, bits('m)) = read_vreg(num_elem, SEW, 0, vd);
  result      : vector('n, dec, bits('m)) = undefined;
  mask        : vector('n, dec, bool)     = undefined;

  (result, mask) = init_masked_result(num_elem, SEW, 0, vd_val, vm_val);

  /* one body element */
  if mask[0] then result[0] = rs1_val;

  /* others treated as tail elements */
  let tail_ag : agtype = get_vtype_vta();
  foreach (i from 1 to (num_elem - 1)) {
    result[i] = match tail_ag {
      UNDISTURBED => vd_val[i],
      AGNOSTIC    => vd_val[i] /* TODO: configuration support */
    }
  };

  write_vreg(num_elem, SEW, 0, vd, result);
  vstart = zeros();
  RETIRE_SUCCESS
}