parser.parseOptionalAttrDict(op_attrs) ||
      parser.parseOptionalAttrDict(op_func_attrs))
    return mlir::failure();

  int64_t num_results = 0;
  if (succeeded(parser.parseOptionalColon())) {
    mlir::IntegerAttr attr;
    mlir::NamedAttrList attrs;
    if (failed(parser.parseAttribute(attr, "num_results", attrs)))
      return mlir::failure();
    num_results = attr.getValue().getSExtValue();