public int getAddressShiftAmount() {
		throw new UnsupportedOperationException(
			"Language for upgrade use only (getAddressShiftAmount)");
	}
If this old language corresponds to a legacy language which was tied to a
specific compiler specification, a suitable ID will be returned.

@return associated compiler specification ID or null if unknown
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/util/OldLanguage.java