// 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];

        PropagateInputToOutput(op->getOperand(result.getResultNumber()),
                               result);
    } else if (auto while_op = dyn_cast<WhileOp>(op)) {
      AnalyzeWhileLoop(while_op, backtrack_analysis.GetAnalysisForFunc(
                                     while_op.body_function()));
    } else if (auto while_region = dyn_cast<WhileRegionOp>(op)) {

  module.walk([&](mlir::TFL::WhileOp while_op) {
    auto cond = symbol_table.lookup<mlir::func::FuncOp>(
        while_op->getAttr("cond").cast<mlir::FlatSymbolRefAttr>().getValue());
    AddCallOpInWhileOpRegion(while_op.getCond(), cond);
    while_op->removeAttr("cond");
    auto body = symbol_table.lookup<mlir::func::FuncOp>(
        while_op->getAttr("body").cast<mlir::FlatSymbolRefAttr>().getValue());

  // Recreate the while op.
  OpBuilder builder(while_op);
  // Now use the filtered original operands, which will be replaced by
  // AddLoadsStoresOutsideControlFlowOp().
  auto new_while = builder.create<TF::WhileOp>(
      while_op.getLoc(), body.getFunctionType().getResults(),
      FilterRange<Value, OperandRange>(while_op.getOperands(),
                                       resource_arg_uses),

      MarkOutsideCompiled(host_if.getOperation());
    }
    if (auto while_op = llvm::dyn_cast<mlir::TF::WhileRegionOp>(op)) {
      if (!HasOutsideCompilationNested(op)) return WalkResult::advance();
      OpBuilder builder(while_op);
      auto host_while = CloneEmptyWhile(while_op.getParallelIterations(),
                                        while_op.getLoc(), builder);
      const auto condition_send_recv_key =

                                TF::WhileOp* while_op) {
  // Given a while loop body function 'body_func', find the tf.While Op that
  // uses it.
  auto uses_optional = body_func.getSymbolUses(module);
  if (!uses_optional.has_value()) {
    body_func.emitOpError() << "no use of while loop body";
    return LogicalResult::failure();
  }
  *while_op = nullptr;
  for (auto& use : uses_optional.value()) {

  LogicalResult matchAndRewrite(WhileRegionOp while_op,
                                PatternRewriter &rewriter) const override {
    auto &body_block = while_op.getBody().front();
    auto &cond_block = while_op.getCond().front();
    bool changed = false;
    for (int op_idx : llvm::seq<int>(0, while_op.getNumOperands())) {
      auto body_arg = body_block.getArgument(op_idx);

          return logical_device;
        }

        if (auto while_op = llvm::dyn_cast<mlir::TF::WhileRegionOp>(owner)) {
          const int operand_number = use.getOperandNumber();
          next_values_to_visit.push_back(
              while_op.getCond().front().getArgument(operand_number));
          next_values_to_visit.push_back(
              while_op.getBody().front().getArgument(operand_number));
          continue;