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I don’t mind the name “RISC” but the term “CISC” always seemed inappropriate. It sort of implies that there are or were competing schools of thought around proc

I don’t mind the name “RISC” but the term “CISC” always seemed inappropriate. It sort of implies that there are or were competing schools of thought around processor architecture when in reality so-called CISC represented an earlier trend and RISC represents a later trend. Neither trend were very intentional by their designers (e.g. why would anyone intentionally make their processor “complex”?) but instead were consequences of the technology available at the time and were simply the most reasonable ways to go about things. So called CISC designs emerge from a time when assembly programming was widespread, RISC came about once compilers were in widespread use. Reasonable engineers with constraints from both eras were focused on producing highly efficient designs. Which is why the term “CISC” rubs me the wrong way. I almost have to wonder to what extent this naming was subversive product marketing leaking into academia. Of course today we have the hindsight to see that the constraints of contemporary processor design requires a significant amount of design elements from both RISC and CISC methodologies.

fulafel 6y ago
Sure cisc as a term was invented by risc. But non-risc (better term?) and risc have coexisted for 30+ years with no sign of x86 fading, and a new type of succesful non risc architectural style, vliw, has come about.
- CyberRabbi 6y ago
  CISC designs have largely faded, in fact, since the beginning of the 32-bit era. Contemporary X86 is internally a RISC design. Not to mention all contemporary so-called RISC processors (power, arm) have hundreds of instructions and plenty non-risc style instructions.
  - fulafel 6y ago
    Re your second point: CISC and RISC are primarily characterisations of the instruction set architecture, not microarchitecture. (And of course this microarchitecture level translation was done with microcode already long before RISC was invented. )

fulafel 6y ago

Sure cisc as a term was invented by risc. But non-risc (better term?) and risc have coexisted for 30+ years with no sign of x86 fading, and a new type of succesful non risc architectural style, vliw, has come about.

CyberRabbi 6y ago
CISC designs have largely faded, in fact, since the beginning of the 32-bit era. Contemporary X86 is internally a RISC design. Not to mention all contemporary so-called RISC processors (power, arm) have hundreds of instructions and plenty non-risc style instructions.
- fulafel 6y ago
  Re your second point: CISC and RISC are primarily characterisations of the instruction set architecture, not microarchitecture. (And of course this microarchitecture level translation was done with microcode already long before RISC was invented. )