Re:STM32MP2: ST’s first Linux capable 64-bit MPU with NPU, G...
by kragen on Saturday August 26, 2023 @06:22PM
(#37277441)
yes, the more complex arm isa runs counter to formal verification, and so does the complexity and secrecy of the arm implementation
lots of realtime systems still don't bother with formal verification, even though it's enormously more accessible today than 20 or 40 years ago
Yeah, when you have that much ram, code density advantage matters less (although in L1$ it will still matter), and other factors weight more.
When it's designed for realtime, then high assurance and formal verification enter the game. There, I'd argue that the complexity of the ARM ISA runs counter to the goals, and RISC-V does an order of magnitude better.
>this weekend i'm prototyping a jit compiler with the objective of keeping most of my code in a bytecode form that's denser than even thumb-2 or rv32c; i anticipate about 20% better code density and about a 2-4× slowdown, with on the order of 64 clocks per instruction of compilation time. i think this should mostly eliminate the rv64c code density advantage, which i agree is pretty killer. that's not why i'm doing it, of course (i love risc-v)
Seems you're having a fun weekend. I am instead playing with old hardware, and reading some 80s book on serial comms.