private void disassembleAt(Address addr) {
		if (listing.getInstructionAt(addr) == null) {
			disassemblyPoints.addRange(addr, addr);
		}
	}
Attempt to markup FReg access instruction with register reference.

@param instr
@return register name if identified, else null
Ghidra/Processors/PIC/src/main/java/ghidra/app/plugin/core/analysis/Pic17c7xxAnalyzer.java