public String getFormattedInstructionMask(int opIndex) {
		byte[] mask = opIndex < 0 ? getInstructionMask() : getOperandValueMask(opIndex);
		return getFormattedBytes(mask);
	}
Return general/operand bit mask formatted as a String
@param opIndex operand index or -1 for mnemonic mask
@return bit mask string
Ghidra/Framework/SoftwareModeling/src/main/java/ghidra/app/plugin/processors/sleigh/SleighDebugLogger.java