for (auto ret_op : ret->getOperands()) {
      return_types.push_back(ret_op.getType());
    }
    auto newType =
        FunctionType::get(rewriter.getContext(), argument_types, return_types);
    if (f.getFunctionType() == newType) {
      return failure();
    }
    rewriter.modifyOpInPlace(f, [&] { f.setType(newType); });

    // Adjust the type of the return values callers of the function to