public int codeSize() {
    int sz = size();

    if (sz == 0) {
      return 0;
    }

    DalvInsn last = get(sz - 1);
    return last.getNextAddress();
  }
Gets the size of this instance, in 16-bit code units. This will only return a meaningful result
if the instructions in this instance all have valid addresses.

@return {@code >= 0;} the size
android/android_framework/dex-maker/src/main/java/com/android/dx/dex/code/DalvInsnList.java