return %ret : tensor<?xf32>
  }
}

// -----

module attributes {tf_saved_model.semantics} {
  // expected-error@+1 {{no predecessor}}
  func.func @f() -> () attributes {tf_saved_model.exported_names = ["f"]} {
  ^entry():
    return
  ^deadcode(%0: tensor<!tf_type.resource<tensor<?xf32>>>):

    int incoming_ctrl_edges = 0;
    int incoming_data_edges = 0;
    op.walk([&](Operation* child) {
      ancestor[child] = &op;
      for (Operation* predecessor : ctrlPredecessors(child)) {
        if (predecessor->getBlock() == &block) {
          incoming_ctrl_edges++;
        }
      }
      for (Value v : child->getOperands()) {
        if (v.getParentBlock() == &block) {

    }

    // insertion point for new entry is after predecessor
    // note predecessor must still be a valid entry: either we deleted an entry that was *not*
    // predecessor, or we didn't delete anything

    ensureCapacity(size + 1);
    keys[size] = key;
    values[size] = value;

    insertIntoTableKToV(size, keyHash);
    insertIntoTableVToK(size, valueHash);

                                       &arg)
                    .succeeded()) {
              options.insert(arg);
            }
          }
        } else {
          op->emitOpError("Predecessor op doesn't implement BranchOpInterface");
          return failure();
        }
      }
    }
    if (!options.empty()) {
      if (options.size() != 1) {
        op->emitOpError("Incompatible code paths.");

	// come right after it.
	after := map[ID][]*Block{}

	// Check each loop header and decide if we want to move it.
	for _, loop := range loopnest.loops {
		b := loop.header
		var p *Block // b's in-loop predecessor
		for _, e := range b.Preds {
			if e.b.Kind != BlockPlain {
				continue
			}
			if loopnest.b2l[e.b.ID] != loop {
				continue
			}
			p = e.b
		}
		if p == nil {
			continue
		}

                    for (Node predecessor : node.getDependencyPredecessors()) {
                        predecessor.addDependencySuccessor(postNode);
                        predecessor.forceAllDependenciesCompleteUpdate();
                        if (!predecessor.allDependenciesComplete()) {
                            readyNodes.removeAndRestart(predecessor);
                        }
                    }

      worklist.push(user_island);
      pred_map[user_island] = curr_op;
    }
  }

  // Construct path by following predecessor pointers.
  IslandOp curr_op = target_op;
  while (curr_op != source_op) {
    // If we don't have a predecessor pointer here, then there is no
    // source-target path.
    if (pred_map.count(curr_op) == 0) return false;
    path.push_back(curr_op);

     * the target state, not the input state. Implicitly, a rule accepts as input the subject in the state that is the predecessor of the target state.
     */
    public BindingPredicate getPredicate() {
        return predicate;
    }

    public boolean isBound() {
        return boundTo != null;
    }

  let constructor = "TFDevice::CreateEmbeddingProgramKeyPass()";
    let description = [{
    Passes in the program key to embedding ops. Will move the embedding ops
    after a _TPUCompileMlir op if there is no predecessor _TPUCompileMlir op.
    Both the embedding op and compile op are assumed to be wrapped in separate
    tf_device.launch() ops. This is because the embedding op is head outside

        // (parent) block, we need to check that it's before (the
        // (parent of) the preprocess_op.
        if (o->isBeforeInBlock(it->second)) {
          break;  // valid compile predecessor
        } else {
          return WalkResult::advance();
        }
      }
      o = o->getParentOp();
    }
    // Check that the the compile op actually passes its results to its parents.