> > If not, one has to set the feature set (-triple and -march passed to > > Clang/llc) to the lowest possible, and it results in much worse > > performing kernel compilation results (no SIMD or other special > > instructions used) which is not nice as OpenCL is all about > > performance. > > > > Do you know if there is such a minimal ISA feature set defined > > for CPU architectures in Debian? > > I will try to find them. But, another possibility is to require an > extended feature set but bails at runtime with a clear error message > if it appears that the current CPU is not powerful enough. I think > that, at least for x86-32, it would be a better option. I know from > previous Debian discussion that the minimal ISA feature set on this > architecture is pretty low but the use case would probably be x86-64 > processors that run 32bits software...
For x86_64 it seems all processors are supported on Debian: http://www.debian.org/releases/stable/amd64/ch02s01.html.en I think the minimum set is not that bad, it has e.g. SSE2. If I understand correctly, this is the "x86-64" CPU for LLVM (note the underscore in the arch vs. dash in the CPU variant...) For x86, the minimum requirement seems to be the 486: http://www.debian.org/releases/stable/i386/ch02s01.html.en which kills performance. ARM is supported on "any ARM CPU". http://www.debian.org/releases/stable/armhf/ch02s01.html.en This suggests some really old ARM ISA - but pocl is exclusively tested on ARMv7 (Cortex-series). To add to the confusion, the NEON SIMD extension is not to my knowledge mandated even by the ARMv7, so to be portable even here, it would have to disable the SIMD. And then there are all the other cpu architectures pocl 0.10 is not tested on... Bailing out run-time sounds like a nice solution, but probably would need quite a bit of work, or at least quite a bit of testing. The ultimate solution is here to compile the OCL kernel run-time at run-time. But for performance reasons, this would need a bit of code to selectively pick just the few needed kernel functions to compile. kalle ------------------------------------------------------------------------------ Meet PCI DSS 3.0 Compliance Requirements with EventLog Analyzer Achieve PCI DSS 3.0 Compliant Status with Out-of-the-box PCI DSS Reports Are you Audit-Ready for PCI DSS 3.0 Compliance? Download White paper Comply to PCI DSS 3.0 Requirement 10 and 11.5 with EventLog Analyzer http://pubads.g.doubleclick.net/gampad/clk?id=154622311&iu=/4140/ostg.clktrk _______________________________________________ pocl-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/pocl-devel
