@Override
	public void decode(Decoder decoder, SleighLanguage sleigh) throws DecoderException {
//		int el = decoder.openElement(ELEM_CONTEXT_SYM);
		flow = false;
		int id = (int) decoder.readUnsignedInteger(ATTRIB_VARNODE);
		SymbolTable symtab = sleigh.getSymbolTable();
		vn = (VarnodeSymbol) symtab.findSymbol(id);
		int attrib = decoder.getNextAttributeId();
		boolean lowMissing = true;
		boolean highMissing = true;
		while (attrib != 0) {
			if (attrib == ATTRIB_LOW.id()) {
				low = (int) decoder.readSignedInteger();
				lowMissing = false;
			}
			else if (attrib == ATTRIB_HIGH.id()) {
				high = (int) decoder.readSignedInteger();
				highMissing = false;
			}
			else if (attrib == ATTRIB_FLOW.id()) {
				flow = decoder.readBool();
			}
			attrib = decoder.getNextAttributeId();
		}
		if (lowMissing || highMissing) {
			throw new DecoderException("Missing high/low attributes");
		}
		patval = (PatternValue) PatternExpression.decodeExpression(decoder, sleigh);
		decoder.closeElement(ELEM_CONTEXT_SYM.id());
	}
Get the ending bit of the context value within the "global" buffer, after
the values have been packed.
@return the ending bit
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/processors/sleigh/symbol/ContextSymbol.java