alt Hacker NewsBy MMIO semantics do you mean explicit load and store instructions? I’ve never felt that pointer reads or writes were lacking descriptiveness here. I would argue the only surprising thing is that they might be optimized out (which is what volatile prevents).
Volatile on a non pointer value is not for MMIO, though, that’s typically for concurrency like with interrupts.
> I’ve never felt that pointer reads or writes were lacking descriptiveness here. I would argue the only surprising thing is that they might be optimized out
The C and C++ languages would be very slow by modern standards if you insist that reading or writing via a pointer must result in immediate fetches or stores to memory.
> Volatile on a non pointer value is not for MMIO, though, that’s typically for concurrency like with interrupts.
You're holding it wrong. Perhaps you've been holding it wrong for so long and so confidently that you've distorted the world around you -- indeed on MSVC on x86 or x86-64 that actually happened -- but, you're still holding it wrong.