public InsnList withRegisterOffset(int delta) {
    int sz = size();
    InsnList result = new InsnList(sz);

    for (int i = 0; i < sz; i++) {
      Insn one = (Insn) get0(i);
      if (one != null) {
        result.set0(i, one.withRegisterOffset(delta));
      }
    }

    if (isImmutable()) {
      result.setImmutable();
    }

    return result;
  }
Returns an instance that is identical to this one, except that the registers in each
instruction are offset by the given amount. Mutability of the result is inherited from the
original.

@param delta the amount to offset register numbers by
@return {@code non-null;} an appropriately-constructed instance
android/android_framework/dex-maker/src/main/java/com/android/dx/rop/code/InsnList.java