@Override
	public T evaluateOp(Program program, PcodeOp op) {
		return evaluateOp(program, op, new HashMap<>());
	}
Evaluate a {@link PcodeOp#LOAD} op

@param program the program defining the static context
@param op the op whose output to evaluate
@param already a cache of already-evaluated varnodes and their values
@return the output value
Ghidra/Debug/ProposedUtils/src/main/java/ghidra/pcode/eval/AbstractVarnodeEvaluator.java