← Back to context

Comment by mshockwave

1 year ago

Zb extension is in both RVA22 and RVA23 profiles, meaning application cores (targeting consumer devices like smartphones) designed in the past few years almost certainly have shXadd instructions in order to be compatible with the mainstream software ecosystem

> meaning application cores (targeting consumer devices like smartphones

where are they?

  • You are aware that hardware takes time to build, tapeout and productise?

    On the open-source front, I can right now download a RVA23 supporting RISC-V implementation, simulate the RTL and have it out perform my current Zen1 desktop per cycle in scalar code: https://news.ycombinator.com/item?id=41331786 (see the XiangShanV3 numbers)

    • RISC-V has existed for over a decade and in that time no one has got close to building a competitive non microcontroller level CPU with it.

      How long is this supposed to take?

      How long until it is accepted that RISC-V looks like a semiconductor nerd snipe of epic proportion designed to divert energy away from anything that might actually work? If it was not designed for this it is definitely what it has achieved.

      12 replies →