4 ms·
> I agree; all instructions should be the same size in classic RISC That was not true for the original RISC ISAs -- CDC6600, Cray 1, IBM 801, RISC-II -- and it
by brucehoult 4y ago
> I agree; all instructions should be the same size in classic RISC
That was not true for the original RISC ISAs -- CDC6600, Cray 1, IBM 801, RISC-II -- and it is not true now for ARMv7 and RISC-V.
It is only really true for RISC ISAs introduced between about 1985 and 1990.
And Aarch64, where it will come to be recognised as a mistake, in time.
> The quantity of instructions is not as relevant.
True.
A minimal but powerful ISA is a good thing, but it's not the differentiator between RISC and not-RISC. The complexity of each individual instruction is.