return region && region->isProperAncestor(replicate_region);
  };

  for (Value operand : op->getOperands())
    if (!ancestor_of_replicate(operand.getParentRegion())) return false;

  // _TPUDeviceOrdinalPlaceholder implicitly depends on the replica.
  if (llvm::isa<TF::_TPUDeviceOrdinalPlaceholderOp>(op)) return false;

  bool has_replicate_operands = false;

    TF_StrTensor:$summary_metadata
  );

  let results = (outs);

  TF_DerivedOperandTypeAttr T = TF_DerivedOperandTypeAttr<2>;
}

def TF__TPUDeviceOrdinalPlaceholderOp : TF_Op<"_TPUDeviceOrdinalPlaceholder", [Pure]> {
  let summary = [{
Placeholder for a device ordinal that depends on its tf_device.replicate ancestor.
  }];

  let description = [{