nullptr, env, /*config=*/nullptr, TF_GRAPH_DEF_VERSION, flib_def, opts);
  FunctionLibraryRuntime* lib_runtime =
      pflr->GetFLR(ProcessFunctionLibraryRuntime::kDefaultFLRDevice);
  TF_RETURN_IF_ERROR(BackwardsConstAnalysis(*graph, nullptr,
                                            &compile_time_const_nodes,
                                            lib_runtime, IsIntraClusterEdge));

  std::vector<Node*> rpo;

  const DataTypeVector& arg_types = (*fbody)->arg_types;
  std::vector<bool> const_args(arg_types.size());
  // If we can't analyze the const args. Bail out.
  TF_RETURN_IF_ERROR(
      BackwardsConstAnalysis(*((*fbody)->graph), &const_args,
                             /*compile_time_const_nodes=*/nullptr, flr));

  for (size_t i = 0; i < const_args.size(); ++i) {
    if (const_args[i]) {

        OptimizeGraph(flr, subgraph, graph_optimizer_options);

        const int num_args = input_permutation->size();
        std::vector<bool> const_args(num_args);
        TF_RETURN_IF_ERROR(
            BackwardsConstAnalysis(**subgraph, &const_args,
                                   /*compile_time_const_nodes=*/nullptr, flr));

        DataTypeVector arg_types(num_args);

  FunctionLibraryRuntime* lib_runtime =
      pflr->GetFLR(ProcessFunctionLibraryRuntime::kDefaultFLRDevice);
  std::vector<bool> compile_time_const_nodes(graph_->num_node_ids(), false);
  TF_RETURN_IF_ERROR(BackwardsConstAnalysis(
      *graph_, /*compile_time_const_arg_indices=*/nullptr,
      &compile_time_const_nodes, lib_runtime));
  // Iterate over nodes in sorted order so that compiler fuel is deterministic.