3 ms·
On the other hand, depending on the generation, PowerPC can have a whopping number of instructions.
by classichasclass 1y ago
On the other hand, depending on the generation, PowerPC can have a whopping number of instructions.
- ck45 1y agoYes, POWER is an acronym for Power Optimization With Enhanced RISC. There are some wild instructions like cntlzd and lwarx that are more CISC-esque, and everybody’s favorite instruction (by name), eieio
- thequux 1y agoThere was an ISA I saw a while back that featured an "enhanced multiply and accumulate signed" instruction, which of course got the mnemonic "EMACS"
- kps 1y agoPowerPC has ‘Enforce In-Order Execution of I/O’ (eieio).
- billforsternz 1y agoObscure data point of the day; McDonalds is a small but long-standing real estate company in a provincial city in New Zealand. Their website address? eieio.co.nz
- mrweasel 1y agoAt what point have you enhanced your RISC architecture to the point where it becomes CISC?
- kbolino 1y agoUnless you're making it possible to access memory on every instruction that takes an argument, or adding more addressing modes that are redundant with ALU operations, or making registers that can only be used for one purpose, etc., it's not really turning into CISC. The acronyms are misnomers, or maybe you just need to think of what's being "reduced" as the number of micro-ops per high-level instruction. Regardless, you don't turn RISC into CISC just by adding more instructions.
- sgt 1y agoCould it be that they just wanted to call it POWER. And then "Enhanced" RISC made the acronym possible?
- bobmcnamara 1y agoIt's true, but it's the encoding that makes this wordy or simple to emulate.
- inkyoto 1y agoPowerPC is a trimmed down subset of the POWER architecture. The latter has a higher number of instructions, and a POWER CPU can execute the generic PowerPC code but not vice versa (unless compiled for the common set of instructions).