> Not only is it an incumbent switching to another architecture; it's an incumbent switching to another incumbent architecture. ARM is older than PowerPC and almost as old as the Macintosh itself; it came out in 1985.
> I gather that it's true that ARM hasn't been as good about backwards compatibility as some of its competitors, but was ARMv8 really so much of a jump from ARMv7 that one can't count it as part of the same line of processors anymore?
> I wasn't ever really talking about just aarch64; I was talking about all of ARM.
M1 is AArch64 only. You incorrectly brought ARMv8 into the discussion. AArch32 is irrelevant in the context of the M1.
Fair to highlight worse backwards compatibility but then you can't bring back AArch32 which Apple dropped years ago to try to claim that the M1 somehow uses an old architecture.
Is it? It's not like Apple moving MacBooks to M1 happened in a vacuum. M1 is only the latest in a whole series of Apple ARM chips, about half of which were non-aarch64.
That context actually seems extremely relevant to me; it demonstrates that Apple is not just jumping wholesale to a brand new architecture. They migrated the way large companies usually do: slowly, incrementally, testing the waters as they go. And aarch64 was absolutely not involved in the formative stages (which are arguably the most important bits) of that process. It hadn't even come into existence yet when Apple released their first product based on Apple Silicon. Heck, you can make a case that the process's roots go way back before Apple Silicon, all the way back to ~1990, when Apple first shipped the Newton.
Note, too, that the person I was originally replying to didn't say "M1", they said "Apple Silicon." In the interest of leaving the goalpost in one place, I followed that precedent.
> I gather that it's true that ARM hasn't been as good about backwards compatibility as some of its competitors, but was ARMv8 really so much of a jump from ARMv7 that one can't count it as part of the same line of processors anymore?
> I wasn't ever really talking about just aarch64; I was talking about all of ARM.
M1 is AArch64 only. You incorrectly brought ARMv8 into the discussion. AArch32 is irrelevant in the context of the M1.
Fair to highlight worse backwards compatibility but then you can't bring back AArch32 which Apple dropped years ago to try to claim that the M1 somehow uses an old architecture.