Re:How many billions of transistors in your iPhone processor?
by grishka on Monday October 30, 2023 @08:20AM
(#38068491)
The designs are smart. The CPUs themselves are still dumb, which is precisely the reason why speculative execution bugs exist. It's magic up until the point all the tricks spill out. In the end, it's always just logic gates wired together to do certain things — whether it's a Z80 or an M2 Max. All this layered complexity is simply the product of 50 years of iterative improvements.
Re:How many billions of transistors in your iPhone processor?
by John23832 on Monday October 30, 2023 @11:11AM
(#38070435)
I think this is just doubling down and simplifying CPUs to the point of uselessness.
What's the difference between a logic gate and when my index and thumb have a static charge jump between them? About a couple trillion dollars of research.
Re:How many billions of transistors in your iPhone processor?
by Koshkin on Monday October 30, 2023 @11:27AM
(#38070651)
> In the end, it's always just logic gates wired together to do certain things
That seems to me a highly reductive point of view. The whole is always more than the sum of its parts.
That’s not true for any post 1995 desktop CPU.
They just adhere to that model and pretend that that’s all they’re doing but in reality there’s layers of supercomputers inside the CPU: micro-op cache, branch predictor, reorder buffer, rename buffer.
They extract hidden parallelism out of the code, run it in blazing fast multiple instructions per clock cycle (!), and pretend that nothing out of the order happened.
CPUs are extremely complex and extremely smart. They can have errors in their implementation where the unseen branches that it executed can be accessed by some processes, etc. But there’s nothing dumb about CPUs. They are made of a million man-hours of engineering.