// failure.
template <typename OpT>
LogicalResult GetOp(Region* region, OpT* result) {
  *result = {};
  for (auto op : region->getOps<OpT>()) {
    if (*result) return op.emitError("should be unique within a function");
    *result = op;
  }
  return success();
}

LogicalResult RunOnRegion(Region* region) {
  RecvTPUEmbeddingActivationsOp recv_op;
  if (failed(GetOp(region, &recv_op))) return failure();