// and `finalize`.
    regions.push_back(RegionSuccessor(
        &getNext(), getNext().front().getArguments().slice(0, num)));
    regions.push_back(RegionSuccessor(
        &getFinalize(), getFinalize().front().getArguments().slice(0, num)));
  } else {
    // `finalize` branches back to the op itself, not passing any arguments.
    regions.push_back(RegionSuccessor());
  }
}

          this->getOperation()->getOperands().size() - 1);
    }
  } else if (auto regionOp = llvm::dyn_cast<GeneratorDatasetRegionOp>(
                 this->getOperation()->getParentOp())) {
    if (&regionOp.getFinalize() == this->getOperation()->getParentRegion()) {
      // `finalize`'s returns get discarded.
      return MutableOperandRange(this->getOperation(), 0, 0);
    }
  }