public void clear() {
		refmap = null;
		oprefmap = null;
		joinToStorage = null;
		storageToJoin = null;
		joinAllocate = 0;
		vbank.clear();
		opbank.clear();
		bblocks = new ArrayList<>();
		uniqId = 0;
	}
Varnodes and PcodeOps in a coherent graph structure
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/model/pcode/PcodeSyntaxTree.java