4 ms·
This is not achievable. There isn't enough rewritable microcode to do this even as a super slow hack. And even if all of the microcode were rewritable, ucode
by monocasa 2y ago
This is not achievable.
There isn't enough rewritable microcode to do this even as a super slow hack.
And even if all of the microcode were rewritable, ucode is kind of a fallback pathway on modern x86 cores with the fast path being hardwired decode for x86 instructions.
And even if that weren't the case the microcode decode and jump is itself hardwired for x86 instruction formats.
And even if that weren't the case the microops are very non-RISC being 2 address, etc.
- brucehoult 2y agoFamous words.
- snvzz 2y ago>This is not achievable. Maybe. >And even... Suppose any hardcoded path can be disabled, and decode done purely in microcode. Performance would be a function of: - how well the microcode can perform in decoding RISC-V. - how well the actual execution units map to RISC-V instructions. And whether this is worth it, ignoring the effort gone into it and the street cred of making something like this work, would be a function of whether or not it can beat a JIT emulator running on the same hardware.
- deleted 2y ago[deleted]