if (!attrs)
      return op->emitError(
          "backend_config has no 'attributes' key or the attributes value is "
          "not a dictionary");

    auto calledComputations = op.getCalledComputations();
    if (!calledComputations || calledComputations.size() != 1)
      return op->emitError("expected exactly one called_computation");

    auto decomposition = mlir::cast<FlatSymbolRefAttr>(calledComputations[0]);

    }

    auto called_computations = op.getCalledComputations();
    if (called_computations.size() != 1) {
      return op.emitOpError()
             << "ApproxTopK takes exactly 1 called_computation.";
    }
    mlir::func::FuncOp callee = module_op_->lookupSymbol<mlir::func::FuncOp>(
        mlir::cast<FlatSymbolRefAttr>(op.getCalledComputations()[0]));