Function Verify

tensorflow/compiler/mlir/tensorflow/ir/tf_executor.cc:192–237

namespace {

LogicalResult Verify(GraphOp graph) {
  auto *executorDialect = graph.getDialect();

  if (graph.GetBody().empty())
    return graph.emitOpError() << "expects a non-empty body";

  // Only tf_executor dialect operations are allowed to be immediately nested
  // in a tf_executor.graph region.
  for (Operation &op : graph.GetBody()) {
    if (op.getDialect() != executorDialect)
      return op.emitOpError() << "unallowed inside a tf_executor.graph region";
    if (isa<GraphOp>(op))
      return op.emitOpError()
             << "unallowed directly inside another tf_executor.graph";
  }

  Operation &fetch = graph.GetBody().back();
  if (!isa<FetchOp>(fetch))
    return fetch.emitOpError()
           << "invalid tf_executor.graph terminator, fetch expected";

  // Ensure that the fetch terminator operands matches the graph result type.
  // All the non-control operands of the fetch operation must match the graph
  // returned value.
  if (fetch.getNumOperands() < graph.getNumResults())
    return fetch.emitOpError() << "does not have enough operands to cover the "
                                  "graph returned values";
  for (int i : llvm::seq<int>(0, fetch.getNumOperands())) {
    Value operand = fetch.getOperand(i);
    // Break out of the loop at the first control operand encountered.
    if (operand.getType().isa<ControlType>()) {
      if (i != graph.getNumResults())
        return fetch.emitOpError()
               << "operand #" << i
               << " is a control type, can't be bound to a graph result";
      break;
    }
    if (i >= graph.getNumResults())
      return fetch.emitOpError()
             << "operand #" << i << " does not have a graph results to bind";
    if (graph.getResult(i).getType() != operand.getType())
      return fetch.emitOpError()
             << "operand #" << i << " type mismatch graph results";
  }
  return success();
}

void Print(GraphOp graph, OpAsmPrinter &p) {
  p << graph.getOperationName();