def clc_core_fn_name(dst, size='', mode='', sat=''):
  """
  This helper function returns the correct clc core conversion function name
  for a given source and destination type, with optional size, mode
  and saturation arguments.
  """
  return "__clc_convert_{DST}{N}{SAT}{MODE}".format(DST=dst, N=size, SAT=sat, MODE=mode)