Re: [Discuss-gnuradio] Beagle board update

[Eric Blossom]

On Thu, Oct 23, 2008 at 09:38:26PM -0700, Philip Balister wrote:
> I have some NEON code in the fff dotproduct routine, the qa code passes:
> 
> address@hidden:/home/balister/oe/tmp/work/armv7a-angstrom-linux-gnueabi/gnuradio-3.1.3+svnr9809-r4.1/trunk/gnuradio-core/src/tests#
> ./test_filter
> . [generic] [cortex_a8]
> . [generic] [cortex_a8]
> . [generic]
> . [generic]
> . [generic]
> . [generic]
> .>>> gr_fir_fff: using cortex_a8
> ..
> OK (9 tests)
> 
> 
> address@hidden:/home/balister/oe/tmp/work/armv7a-angstrom-linux-gnueabi/gnuradio-3.1.3+svnr9809-r4.1/trunk/gnuradio-core/src/tests#
> ./benchmark_dotprod_fff
>     generic: taps:  256  input: 4e+07  cpu: 968.586  taps/sec:  1.057e+07
>  cortex_a8: taps:  256  input: 4e+07  cpu: 45.703    taps/sec:  2.241e+08
> 
> Philip

Cool!

The good news / bad news is that the spread is worse than on the P4!

Is there a way to get the compiler to use the NEON instruction set in
scalar mode?  E.g., something like -mfpmath=sse on x86?  Maybe -mfp=vfp?
Are you providing the -mcpu=cortex-a8 gcc option?

Eric