public void popBuild() {
		if (point == null) {
			maxsize = 0;
			oparray = null;
			return;
		}
		point = point.getParent();
		depth -= 1;
		if (point != null)
			setupPoint();
		else {
			maxsize = 0;
			oparray = null;
		}
	}
Move to the parent of the current node
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/processors/sleigh/OpTplWalker.java