public BigInteger getConst() {
		BigInteger result = BigInteger.ZERO;
		for (Varnode vn : nodes) {
			if (!vn.isConstant()) {
				return null;
			}
			result = result.shiftLeft(vn.getSize() * 8);
			result = result.or(vn.getAddress().getOffsetAsBigInteger());
		}
		return result;
	}
If the location represents a constant, get its value

@return the constant value
Ghidra/Framework/Emulation/src/main/java/ghidra/pcode/exec/ValueLocation.java