@Override
	public void decode(Decoder decoder) throws DecoderException {
		int el = decoder.openElement(ELEM_INSTRUCT_PAT);
		maskvalue = new PatternBlock(true);
		maskvalue.decode(decoder);
		decoder.closeElement(el);
	}
Matches against the actual instruction bit stream
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/processors/sleigh/pattern/InstructionPattern.java