code: def nn_backend_passes(prog):
      passes = [
          "nn_backend::commingle_loop_vars",  # after loop_invariant_elimination
          "nn_backend::handle_return_inputs_as_outputs",
          "common::const_elimination",
          "common::dead_code_elimination",
          "nn_backend::handle_unused_inputs",  # must come after dce.
          "nn_backend::alert_return_type_cast",  # must be at the end.
      ]
  
      prog.validate()
      for p in passes:
          logging.info(
              'Performing passes for nn_backend: "{}"'.format(p)
          )
          PASS_REGISTRY[p](prog)
          # No more validation from this point on as prog is not SSA anymore.
  
      logging.debug("Program after nn backend passes:\n{}".format(prog))
  
label_desc: Use image node_id 1 for calling a global function with example usage: nn_backend_passes(prog) without return types