public void unSetInput(PcodeOp op, int slot) {
		VarnodeAST vn = (VarnodeAST) op.getInput(slot);
		vn.removeDescendant(op);
		op.setInput(null, slot);
	}
return all PcodeOps associated with a particular instruction Address
@param addr -- Address of instruction generating PcodeOps
@return -- Iterator to PcodeOps
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/model/pcode/PcodeSyntaxTree.java