In general for moving from v8 to v9, I think 16% is extremely pessimistic. Removal of aarch32 has huge implications. And this is not limited to CPU but also t

In general for moving from v8 to v9, I think 16% is extremely pessimistic. Removal of aarch32 has huge implications. And this is not limited to CPU but also touches MMU, caches and more that in v8 had to provide aarch32 compatible interfaces. This lead to really inefficient designs (for example, MMU walk which is extremely critical to performance is more than twice as complicated in ARMv8 compared to v7 and v9). The space saved by removing these can be used for bigger caches, wider units, better branch prediction and other fun stuff. Finally, note also that the baseline X1 numbers come from Samsung who we all know are worst in class right now. And they are using an inferior process. Let's see what qcomm, ampere and amazon can do with v9.