PropagatePotentiallyWrittenUpFromCallee(func.getRegion(),
                                                call.getArgOperands());
      }
      return;
    }
    if (auto if_op = dyn_cast<TF::IfOp>(op)) {
      for (auto callee : {if_op.then_function(), if_op.else_function()}) {
        PropagatePotentiallyWrittenUpFromCallee(callee.getRegion(),

  // corresponding callOp, propagate the potentially written decision to the
  // callOp's operands, if the corresponding region's arguments are potentially
  // written resources.
  void PropagatePotentiallyWrittenUpFromCallee(
      Region& region, Operation::operand_range propagate_to);

  // Marks 'resource' as written.
  void SetPotentiallyWritten(Value resource);

  struct ResourceInfo {