On Mon, Sep 29, 2008 at 03:13:09PM -0700, Inderaj Bains wrote: > Thanks Eric, > Yes I want to use SIMD. Since I want to spend most time improving > performance, it would be nice if I can start off from something functioning > or put together something quickly. > How much effort would it be to get a GSM (other?) all software system > together (except A/D I guess). Maybe I could use pre-generated streams on > both ends in software. > > Thanks > Inderaj
This is great. What we've been thinking about is building a library of SIMD accelerated primitives, along the lines of Intel's Integrated Performance Primitives. The crucial differences would be: free software (GPLv3); support for SSE, SSE2, SSE3, Altivec and Cell SPE instruction sets. Our working title for this is the "Generic Performance Primtives" (GPP). One unresolved issue is what code to start with. We need a framework that provides for reference implementations, QA, testing all argument alignments, correctness, performance, etc; runtime dispatch based on the equivalent of cpuid; can be built as both shared and static libraries (need static on the SPE). The basic idea (for the user visible routines) would be to start with the well thought out API described in Volume 1 (Signal Processing) of the IPP docs, peforming a s/ipp/gpp/g. http://softwarecommunity.intel.com/isn/downloads/softwareproducts/pdfs/346499.pdf http://softwarecommunity.intel.com/isn/downloads/softwareproducts/pdfs/346532_userguide_win_ia32.pdf Two possible starting points are: liboil http://liboil.sourceforge.net (currently x86, x86-64 and PPC) Framewave http://framewave.sourceforge.net (x86 and x86-64 only) (Framewave is built on top of SSEPlus, a thin wrapper on top of the SSE C/C++ intrinsics. http://sseplus.sourceforge.net Mostly it appears that they provide emulations for instructions that are missing at a particular level. E.g., your code could target SSE3, and they'd emulate the missing addsub instruction in terms of SSE.) For starters, it would be great if you could look at these two options (and any others that you come across) and let us know how you think these would work out as starting points, given the requirements above. If this seems like more than you want to bite off, I can provide a list of high-priority functions and you could start implementing the reference version and any of the SSE*, Altivec or SPE versions that grab your attention. We're big on complex arithmetic :-) Please let me know how this sounds and if you've got any comments or questions. Thanks! Eric _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
