On Monday, July 30, 2018, Bill Kontos vkontogpls@gmail.com wrote:
I've read somewhere that this requires specifically compiled binaries to work because it lacks some instructions. Is that correct?
Compressed, the 16 bit alternative representations for certain common instructions, yes.
UCB ASSUMED that ALL systems running linux would automatically have these because of COURSE it is optimal in ALL circumstances, without fucking well consulting anyone outside of their elite clique / cartel, as to whether this was actually the case.
Hint: For VLIW its actually much easier and better to keep to regular 32bit, because of the branch prediction, and just absolutely go mental on the memory bus bandwidth.
Prior to UCBs interference both Fedora and Debian had been compiled as RV64IMAFD ie without compressed, which would easily have permitted multiarch to have dual C and nonC binaries and libraries installed.
Now there will need to be a fork of both debian and fedora created, exactly as the RISCV foundation CLAIMED that they were working to avoid happening by "learning from the mistakes of the past"
rriiiight...
If so
will this limitation carry forward to other designs from the team?
If they implement C it will be fine.
The primary thing is that demand for sovereign processors is so high from various India Govt departments that they are overwhelmed with the rote task of integrating peripherals onto AXI4 buses. So i have spent the past 10 days urgently focussed on writing an autogenerator which creates the HDL source code including the fabric and bus architecture, from a formal spec in about 0.25 seconds flat.
Now the team will be free to work on much more strategic research like VLIW xBitManip SIMD 3D graphics Vectors and Compressed and a more efficient RV16 encoding that will produce far more compact code than Compressed can.
Also it turns out that one of the students is doing a phd into fabric autogeneration and optimisation. He was by a fantastic coincidence missing the tool that would actually generate the code so that it could be properly tested and synthesised.
Professor Kamakoti wrote all of Intel's formal verification test suites when he used to work for them, and he is a big fan of dynamic reconfigureable fabrics to suit different workloads. Its the RISE lab. Reconfigurable something.
Its gonna get really really interesting. They have over 20 people on the core team and they get like 20 to 30 interns helping over the summer for 6 months. Oh and me, skating around the campus, feeding the monkeys, farting and using um colourful language shall we say, and writing python that spits out BSV like it was born to Rock.
This is not a small operation, its set to completely steamroller ARM, Intel and the RISCV Foundation itself if they dont wake up. All entirely libre licensed and developed along informal IETF / ASF lines not a private club /clique / cartel.
L.