private void parseContextFields(Element element, RegisterBuilder regBuilder, Address addr,
			int contextBitLength) throws SAXException {

		List<?> children = element.getChildren();
		Iterator<?> iter = children.iterator();
		while (iter.hasNext()) {
			Element childElement = (Element) iter.next();
			String elementName = childElement.getName();
			if (!"field".equals(childElement.getName())) {
				throw new SAXException(
					"Unsupported context_register element '" + elementName + "'");
			}
			String name = childElement.getAttributeValue("name");
			if (name == null) {
				throw new SAXException("Missing required field 'name' attribute");
			}
			String range = childElement.getAttributeValue("range");
			if (range == null) {
				throw new SAXException("Missing required field 'range' attribute");
			}
			int lsb = -1;
			int msb = -1;
			try {
				String[] splitRange = range.split(",");
				lsb = Integer.parseInt(splitRange[0]);
				msb = Integer.parseInt(splitRange[1]);
				int fieldBitLength = msb - lsb + 1;

				// Transpose bit numbering from Sleigh convention in file to big-endian register context bit numbering
				lsb = contextBitLength - msb - 1;
				msb = lsb + fieldBitLength - 1;
			}
			catch (Exception e) {
			}
//			if (lsb < 0 || msb < 0 || msb < lsb || lsb > 31 || msb > 31) {
//				throw new SAXException("invalid field range: " + range);
//			}
			regBuilder.addRegister(name, name, addr, (contextBitLength + 7) / 8, lsb, msb - lsb + 1,
				true, Register.TYPE_CONTEXT);
		}

	}
Returns language description associated with this old language.
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/program/util/OldLanguage.java