code: private void sort(InstructionGroup group) {
          final InsnList instructions = method.instructions;
          Collections.sort(group.getNodes(), new Comparator<InstructionGraphNode>() {
              public int compare(InstructionGraphNode a, InstructionGraphNode b) {
                  return Integer.valueOf(instructions.indexOf(a.getInstruction()))
                          .compareTo(instructions.indexOf(b.getInstruction()));
              }
          });
      }
docs: sort the group instructions according to their method index