@Override
	public boolean isMatch(ParserWalker walker, SleighDebugLogger debug)
			throws MemoryAccessException {
		boolean match = maskvalue.isContextMatch(walker);
		debugPatternMatch(debug, walker, match);
		return match;
	}
Pattern which depends only on the non-instruction stream bits
of the context
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/processors/sleigh/pattern/ContextPattern.java