rewriter.replaceOp(op, converted.getResults());
    return success();
  }
};

struct ConvertTensorListPushBack
    : public OpRewritePattern<TF::TensorListPushBackOp> {
  using OpRewritePattern::OpRewritePattern;

  LogicalResult matchAndRewrite(TF::TensorListPushBackOp op,
                                PatternRewriter& rewriter) const override {
    // It is currently not possible to easily pack the output of a multi-result

    return CreateI32SplatConst(op.getLoc(), rewriter, {1}, 0);
  }
};

struct ConvertTensorListPushBack
    : public OpConversionPattern<TF::TensorListPushBackOp> {
  using OpConversionPattern::OpConversionPattern;

  LogicalResult matchAndRewrite(
      TF::TensorListPushBackOp op, OpAdaptor adaptor,
      ConversionPatternRewriter &rewriter) const override {
    Value input_handle = adaptor.getOperands()[0];

  (*buffer_to_size)[buffer] = {size, /*fixed=*/true};
  list.getOutputHandle().replaceAllUsesWith(buffer);
  list.erase();
  return success();
}

LogicalResult HandleTensorListPushBackOp(
    TF::TensorListPushBackOp push,
    llvm::SmallDenseMap<Value, SizeInfo>* buffer_to_size) {
  auto buffer = push.getInputHandle();
  auto it = buffer_to_size->find(buffer);
  if (it == buffer_to_size->end()) {
    return push.emitOpError(

      GET_OPERATION_NAME(mlir::TF::EmptyTensorListOp),
      GET_OPERATION_NAME(mlir::TF::TensorListReserveOp),
      GET_OPERATION_NAME(mlir::TF::TensorListFromTensorOp),
      GET_OPERATION_NAME(mlir::TF::TensorListPushBackOp),
      GET_OPERATION_NAME(mlir::TF::TensorListPopBackOp),
      GET_OPERATION_NAME(mlir::TF::TensorListGetItemOp),
      GET_OPERATION_NAME(mlir::TF::TensorListSetItemOp),

    // (conceptually) modify it i.e., ops that take an input TensorList and
    // produce an output TensorList.
    for (auto& use : tensorlist.getUses()) {
      if (auto push = llvm::dyn_cast<TensorListPushBackOp>(use.getOwner())) {
        auto element_type =
            mlir::dyn_cast<RankedTensorType>(push.getTensor().getType());
        if (!verify_and_update_potential_element_type(element_type))
          return false;