private void handlePclModification(Instruction instr) {
		String mnemonic = instr.getMnemonicString();
		if ("MOVWF".equals(mnemonic)) {
			if (wContext.hasValue()) {
				handleComputedFlow(instr, wContext.longValue(), Reference.MNEMONIC);
			}
			else {
				Msg.warn(this,
					"Unhandled PCL modification (WREG unknown): " + instr.getMinAddress());
			}
		}
		else if ("MOVFP".equals(mnemonic) || "MOVPF".equals(mnemonic)) {
			Object[] objs = instr.getOpObjects(0);
			if (objs.length == 0 && (wReg.equals(objs[0]) || wReg.getAddress().equals(objs[0])) &&
				wContext.hasValue()) {
				handleComputedFlow(instr, wContext.longValue(), Reference.MNEMONIC);
			}
			else {
				Msg.warn(this,
					"Unhandled PCL modification (WREG unknown): " + instr.getMinAddress());
			}
		}
	}
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