// yield.
    SmallVector<Value, 4> new_results(old_num_operands);
    int next_idx = 0;
    for (int op_idx : llvm::seq<int>(0, old_num_operands))
      if (!removed_operand.test(op_idx))
        new_results[op_idx] = new_while_op.getResult(next_idx++);

    rewriter.replaceOp(while_op, new_results);
    return success();
  }
};

}  // anonymous namespace

        // *before* returning newValue from the cache query.
        return transform(
            newValue,
            newResult -> {
              LoadingValueReference.this.set(newResult);
              return newResult;
            },
            directExecutor());
      } catch (Throwable t) {
        ListenableFuture<V> result = setException(t) ? futureValue : fullyFailedFuture(t);

        // *before* returning newValue from the cache query.
        return transform(
            newValue,
            newResult -> {
              LoadingValueReference.this.set(newResult);
              return newResult;
            },
            directExecutor());
      } catch (Throwable t) {
        ListenableFuture<V> result = setException(t) ? futureValue : fullyFailedFuture(t);

        pack_op.getValuesCount() != input_unpack_op.getNum())
      return failure();

    const int total_pack_inputs = pack_op.getNumOperands();
    const int num_results = input_unpack_op.getNumResults();
    if (total_pack_inputs != num_results) return failure();
    for (auto input_output :
         llvm::zip(pack_op.getOperands(), input_unpack_op.getResults())) {
      Value pack_input = std::get<0>(input_output);