private int pow2(int pow) {
		int r = 1;
		for (int i = 1; i <= pow; i++) {
			r *= 2;
		}
		return r;
	}
Returns the map from context register values to disassembly display prefixes
@return map values->prefixes
Ghidra/Extensions/SleighDevTools/src/main/java/ghidra/app/util/disassemble/GNUExternalDisassembler.java