True, but the basic point still stands. ISA heavily constrains the final design on-die. ARM might not be able to deliver an ISA that fits Apple&#x27;s needs.<p>Apple already has a tweaked version of ARM (ARMv7s) [1]. There may come a day where tweaks no longer cut it. At the end of another excellent post, from the same author [2]:<p>&gt; If compiler–architecture co-design is on the table, much more radical opportunities are available.<p>Apple has both compiler and architecture teams. And if it sees ties to a specific architecture hurting its product development goals again? It seems like exactly the kind of company that would drop the ARM ISA completely.<p>Or at least like the kind of company that wants to keep that option on the table.<p>[1] <a href="http:&#x2F;&#x2F;www.linleygroup.com&#x2F;newsletters&#x2F;newsletter_detail.php?num=4881" rel="nofollow">http:&#x2F;&#x2F;www.linleygroup.com&#x2F;newsletters&#x2F;newsletter_detail.php...</a>
[2] <a href="http:&#x2F;&#x2F;adriansampson.net&#x2F;blog&#x2F;macroscalar.html" rel="nofollow">http:&#x2F;&#x2F;adriansampson.net&#x2F;blog&#x2F;macroscalar.html</a>