> A disadvantage of the RISC design was that since programs required more instructions, they took up more space in memory. Back in the late 1970s, when the first generation of CPUs were being designed, 1 megabyte of memory cost about $5,000. So any way to reduce the memory size of programs (and having a complex instruction set would help do that) was valuable. This is why chips like the Intel 8080, 8088, and 80286 had so many instructions.
> But memory prices were dropping rapidly. By 1994, that 1 megabyte would be under $6. So the extra memory required for a RISC CPU was going to be much less of a problem in the future.
I think this is still a problem? Not memory size, but the speed of the memory bus.
>A disadvantage of the RISC design was that since programs required more instructions,
It's important to understand that, while that was the case back then, today, RISC-V has best 64-bit code density, whereas best 32-bit is still ARM thumb2, with RISC-V being a close 2nd, and actually better with current B and Zc extensions, to be ratified soon.
This is achieved with very little complexity required in the decode, which becomes a net win if there's any ROM or cache in the chip.
> But memory prices were dropping rapidly. By 1994, that 1 megabyte would be under $6. So the extra memory required for a RISC CPU was going to be much less of a problem in the future.
I think this is still a problem? Not memory size, but the speed of the memory bus.