if (auto input_result = mlir::dyn_cast<mlir::OpResult>(src)) {
    auto* input_inst = GetIslandInnerOpOrSelf(input_result.getOwner());
    // Replaces the input node with NextIteration sink if it is a NextIteration
    // source.
    if (auto next_iter_source =
            llvm::dyn_cast<mlir::tf_executor::NextIterationSourceOp>(
                input_inst))
      input_inst = next_iter_source.GetSink();