alt Hacker NewsNot my area of expertise but what exactly is the difference between RISC-V and Power PC? Didn't Power-PC get a good run in the 90s and 2000s? Just wondering why there's renewed interest in RISC-like architectures when industry already had a good exploration of that area.
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Ah, PowerPC. For a RISC processor it surely had a lot of instructions, most of them quite peculiar. But hey, it had fixed-length instruction encoding and couldn't address memory in instructions other than "explicit memory load/store", so it was RISC, right?
It is Chinese companies looking for ARM alternative that push this otherwise mediocre ISA.
It is possible that ARM based CPUs will start eating x86 market slowly. See snapdragon X2 and upcoming Nvidia CPU. Maybe in 10 years new computers will be ARM based and a lot of IoT will run on risc-5.
x86_64 machines are RISC under the hood and have been for ages, I believe; microcode is translating your x64 instructions to risc instructions that run on the real CPU, or something akin to that. RISC never died, CISC did, but is still presented as the front-facing ISA because of compatibility.
The interest is BECAUSE it's well explored territory. The concept is proven and works fine.
On the low end where RISC-V currently lives, simplicity is a virtue.
On the high end, RISC isn't inherently bad; it just couldn't keep up on with the massive R&D investment on the x86 side. It can go fast if you sink some money into it like Apple, Qualcomm, etc have done with ARM.