}

ParseResult GraphOp::parse(OpAsmParser &parser, OperationState &result) {
  llvm::SMLoc loc = parser.getCurrentLocation();

  // Parse the body region.
  Region &body = *result.addRegion();
  if (parser.parseRegion(body)) return failure();

  // Ensure that the region is well formed: it contains at least a block with
  // a FetchOp terminator.
  GraphOp::ensureTerminator(body, parser.getBuilder(), result.location);

  for (auto argAndType : llvm::zip(region_args, region_arg_types)) {
    auto& arg = packed_args.emplace_back();
    arg.ssaName = std::get<0>(argAndType);
    arg.type = std::get<1>(argAndType);
  }
  if (parser.parseRegion(body, packed_args)) return failure();

  // Add derived `operandSegmentSizes` attribute based on parsed operands.
  if (!result.attributes.get(kOperandSegmentSizesAttr)) {

    builder.create<YieldOp>(controlled_op->getLoc(),
                            controlled_op->getResults());
    result.location = controlled_op->getLoc();
  } else if (parser.parseRegion(body)) {
    return failure();
  }

  ControlNodeOp::ensureTerminator(body, parser.getBuilder(), result.location);

  // Get the results type for the control node from the terminator operands.