@Override
	public void decode(Decoder decoder, PcodeFactory pfactory) throws DecoderException {
		for (;;) {
			int attribId = decoder.getNextAttributeId();
			if (attribId == 0) {
				break;
			}
			if (attribId == AttributeId.ATTRIB_VARREF.id()) {
				int refid = (int) decoder.readUnsignedInteger();
				varnode = pfactory.getRef(refid);
				if (varnode != null) {
					if (varnode.getHigh() == null) {
						Msg.warn(this, "VOID high variable problem at " + varnode.getAddress());
						return;
					}
					datatype = varnode.getHigh().getDataType();
				}
				break;
			}
		}
		super.decode(decoder, pfactory);
	}
@return a Varnode representing the return value in the function's data-flow
Ghidra/Features/Decompiler/src/main/java/ghidra/app/decompiler/ClangReturnType.java