docs: @Requires("bytecode != null")
    @Ensures("result != null")
    private byte[] instrumentWithDebug(byte[] bytecode) {
      ClassReader reader = new ClassReader(bytecode);
      ClassWriter writer = new NonLoadingClassWriter(reader, 0);
      reader.accept(new HelperClassAdapter(writer), ClassReader.EXPAND_FRAMES);
      return writer.toByteArray();
    }