@Override
	public void apply(ParserWalker walker, SleighDebugLogger debug) throws MemoryAccessException {
		int val = (int) patexp.getValue(walker);
		val <<= shift;
		walker.getParserContext().setContextWord(num, val, mask);
		if (debug != null) {
			debug.dumpContextSet(walker.getParserContext(), num, val, mask);
		}
	}
An operation on the context (bit-packed form) of an instruction
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/processors/sleigh/ContextOp.java