private DependencyNode getOrCreateDependencyNode(T value) {
		DependencyNode dependencyNode = nodeMap.get(value);
		if (dependencyNode == null) {
			dependencyNode = new DependencyNode(value);
			nodeMap.put(value, dependencyNode);
			unvisitedIndependentSet.add(value);
		}
		return dependencyNode;
	}
Returns the set of values in this graph.
@return the set of values in this graph.
Ghidra/Framework/Generic/src/main/java/ghidra/util/graph/AbstractDependencyGraph.java