return;
    }
    if (auto while_op = dyn_cast<TF::WhileOp>(op)) {
      for (auto callee : {while_op.cond_function(), while_op.body_function()}) {
        PropagatePotentiallyWrittenUpFromCallee(callee.getRegion(),
                                                while_op.getInput());
      }
      return;
    }
    if (auto while_op = dyn_cast<TF::WhileRegionOp>(op)) {

  for (int64_t i = 0; i < while_op.getNumResults(); ++i) {
    auto it = buffer_to_size->find(while_op.getOperand(i));
    if (it == buffer_to_size->end()) continue;
    new_while_operands.push_back(it->getSecond().size);
  }
  auto new_while = builder.create<TF::WhileRegionOp>(
      while_op.getLoc(), body_region.front().getTerminator()->getOperandTypes(),
      new_while_operands, while_op->getAttrs());

          while_op, while_op.getCondAttr());
      func::FuncOp body = SymbolTable::lookupNearestSymbolFrom<func::FuncOp>(
          while_op, while_op.getBodyAttr());
      for (auto &arg : while_op->getOpOperands()) {
        BlockArgument cond_arg = cond.getArgument(arg.getOperandNumber());
        this->join(getLatticeElement(cond_arg), *getLatticeElement(arg.get()));

}

LogicalResult ConvertWhileOp(WhileOp while_op, bool allow_passthrough_args) {
  auto while_region = OpBuilder(while_op).create<TF::WhileRegionOp>(
      while_op.getLoc(), while_op.getResultTypes(), while_op.getInput(),
      while_op.getParallelIterations(), while_op.getIsStateless(),
      while_op.getShapeInvariant());
  CopyDeviceAndUnderscoredAttributes(while_op, while_region);

  YieldOp cond_yield =

      id_map[i] = j++;
      new_operands.push_back(while_op.getOperand(i));
      new_result_types.push_back(while_op.getResultTypes()[i]);
    }
  }

  auto new_while_op = OpBuilder(while_op).create<WhileOp>(
      while_op.getLoc(), new_result_types, new_operands, while_op->getAttrs());
  new_while_op.getCond().takeBody(while_op.getCond());
  new_while_op.getBody().takeBody(while_op.getBody());

  for (auto i = 0; i < n; ++i) {

      read_var->erase();
    } else if (auto while_op = dyn_cast<TF::WhileOp>(user_op)) {
      GetUpdatedWhileOp<TF::WhileOp>(
          while_op, while_op.cond_function().getArgumentTypes(), args_to_erase);
      while_op->erase();
    } else if (auto while_op = dyn_cast<TF::WhileRegionOp>(user_op)) {
      auto new_while_op = GetUpdatedWhileOp(
          while_op, while_op.getCond().getArgumentTypes(), args_to_erase);

  // Create the new while op.
  auto new_while_operands = llvm::to_vector<8>(while_op.getOperands());
  OpBuilder builder(while_op);
  assert(while_op.getNumOperands() == while_op.getNumResults());
  for (int64_t i = 0; i < while_op.getNumResults(); ++i) {
    auto it = data_var_to_size_var.find(while_op.getOperand(i));
    if (it == data_var_to_size_var.end()) continue;

llvm::SmallVector<std::pair<int64_t, llvm::SmallVector<Value, 4>>, 4>
AnnotateCompileOpAndGetExecuteArgToWhileArgsMapping(
    TF::WhileRegionOp while_op, tf_device::ReplicateOp replicate,
    TF::TPUExecuteAndUpdateVariablesOp execute,
    tf_device::LaunchOp compile_launch) {
  Region& body = while_op.getBody();
  Region& cond = while_op.getCond();

  llvm::SmallVector<std::pair<int64_t, llvm::SmallVector<Value, 4>>, 4> mapping;

  auto loc = NameLoc::get(
      builder.getStringAttr("chain_control_outputs@" + while_op.getBody()));
  IslandOp const_wrapper = GetDummyConstant(builder, const_type, loc);

  // Get new operand and result types.
  auto new_operands = llvm::to_vector<4>(while_op->getOperands());
  auto new_result_types = llvm::to_vector<4>(while_op->getResultTypes());
  Value const_output = const_wrapper.getOutputs()[0];

  NameAttrList cond_fn, body_fn;
  cond_fn.set_name("f3");
  body_fn.set_name("f2");
  auto while_op =
      ops::While(s.WithOpName("while"),
                 std::initializer_list<Input>{arg0, arg1}, cond_fn, body_fn);
  auto ret2 = ops::_Retval(s.WithOpName("ret2"), while_op.output[0], 2);
  auto ret3 = ops::_Retval(s.WithOpName("ret3"), while_op.output[1], 3);
  std::unique_ptr<Graph> g(new Graph(OpRegistry::Global()));