// control flow branches might be dead for a given input.
    bool require_always_compilable = false;

    // Whether string constants are compilable.
    bool allow_string_consts = true;

    // Whether to allow the compilation of CollectiveReduceV2Op.
    bool allow_collective_reduce_v2 = true;

    // Whether to allow the compilation of WhereOp.
    bool allow_where_op = true;

        "SymbolicGradient should be handled by IsCompilableCall().";
    return false;
  }

  if (node.type_string() == "Const") {
    const AttrValue* attr = node.attrs().Find("dtype");
    if (!op_filter_.allow_string_consts && attr != nullptr &&
        attr->type() == DT_STRING) {
      *uncompilable_reason =
          "Const op with type DT_STRING is not supported by XLA.";
      return false;
    }
  }

      continue;
    }

    RecursiveCompilabilityChecker::OperationFilter filter =
        CreateOperationFilter(*registration);
    filter.require_always_compilable = true;
    filter.allow_string_consts = false;
    filter.allow_collective_reduce_v2 = false;
    filter.allow_unique_op = false;
    filter.allow_where_op = allow_where_op;

    RecursiveCompilabilityChecker checker(