@Override
	protected boolean isEnabledForDecompilerContext(DecompilerActionContext context) {
		Function function = context.getFunction();
		if (function == null || function instanceof UndefinedFunction) {
			return false;
		}

		PcodeOp callOp = getCallOp(context.getProgram(), context.getTokenAtCursor());
		if (callOp == null) {
			return false;
		}

		// don't enable if override already in place
		return getSymbol(context.getFunction(), context.getTokenAtCursor()) == null;
	}
Try to find the PcodeOp representing the call the user has selected
@param program is the Program
@param tokenAtCursor is the point in the window the user has selected
@return the PcodeOp or null
Ghidra/Features/Decompiler/src/main/java/ghidra/app/plugin/core/decompile/actions/OverridePrototypeAction.java