gistfile1.pde

   @Interp
    public Iterator<LocalVariable> getLiveLocalVariables() {
        Map<LocalVariable, Integer> ends = new HashMap<LocalVariable, Integer>();
        Map<LocalVariable, Integer> starts = new HashMap<LocalVariable, Integer>();
        Set<LocalVariable> variables = new TreeSet<LocalVariable>();

        for (int i = instructions.size() - 1; i >= 0; i--) {
            Instr instr = instructions.get(i);
            Variable variable = instr.result;

            if (variable != null && variable instanceof LocalVariable) {
                variables.add((LocalVariable) variable);
                starts.put((LocalVariable) variable, i);
            }

            for (Operand operand : instr.getOperands()) {
                if (!(operand instanceof LocalVariable)) continue;

                variable = (LocalVariable) operand;

                if (ends.get((LocalVariable) variable) == null) {
                    ends.put((LocalVariable) variable, i);
                    variables.add((LocalVariable) variable);
                }
            }
        }

        return variables.iterator();
    }