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Oh, I think Intel knows it, but they consider it too much of a trade secret to even tell the compiler team about it.

There are actually numerous performance counters exposed by the CPU too, which are good for dynamic benchmarking, but hardly anyone cares to use them.

BTW, even though the ALU part of the CPU is extremely wide and dynamic, you still have to fit your instructions through the x86 decoder at the front, and it's worth writing a scheduler just to model that part.



Why would they keep it secret?

I understand that they need to keep the low level details of their CPU secret, but a memory model? All it says is when/how reads and write commute. If a CPU manufacturer were to provide a nice, high-level memory model, this would make the CPU more sellable. Why? Because compiler writers could more aggressively optimise when compiling for the CPU.

I suspect that the reason they don't give out memory models is that they don't know how to do it. That's also the vibe I've been getting when I talked to people who would know.




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