That would require new instructions, so it would be visible.On the topic of GFX IP level, I am curious whether increased FP16 vs FP32 throughput can sneak under the same version number, or if that is different enough to be visible to the driver.
That said, if you'd simply use previously reserved bits for encoding those and all existing instructions still work all the same, you could probably pretend there weren't any changes (only when you need the new instructions then you'd actually need to distinguish). But why would you do that, you could just say it's gfx ip level 8.1 or so in that case, and noone would have any clue what changed neither...