Re: [Discuss-gnuradio] max and argmax blocks with SIMD instructions

[Robert McGwier]

Trond:

I, as well as GNU radio and others,  need your copyright statement and 
your grant of a GPL license to this code IN the code and header modules. 
It would be best if you added this to your code as soon as possible.

THANK YOU for sharing this.

Bob



Trond Danielsen wrote:
> 2007/4/23, Eric Blossom <address@hidden>:
> > On Mon, Apr 23, 2007 at 10:48:58AM +0200, Trond Danielsen wrote:
> > > Hi everyone,
> > >
> > > I've written a couple of blocks for GNU Radio, but am not satisfied
> > > with the performance. I am therefore thinking of using SIMD
> > > instructions. However, I am not that familiar with x86 assembly
> > > instructions, and finding the reference manual on Intel's website was
> > > not easy. I know that DSPs such as the Blackfin has special vector
> > > instructions that would make this very simple, but I am not sure about
> > > x86.
> > >
> > > I am also going to write a general purpose multiply and accumulate
> > > block that would benefit much from SIMD instructions.
> > >
> > > Any comments are appreciated.
> >
> > Hi Trond,
> >
> > Can you point us at your code?  Before diving into SIMD, it would be
> > good to confirm that there isn't an easier change to make.  Have you
> > run oprofile on your code?
>
> Thanks a lot for your answer, very enlightening!
>
> The max and argmax blocks can be found here:
> ftp://open-gnss.org/pub/opengnss. If you find it useful I do not mind
> including them in GNU Radio.
>
> I haven't profiled the code, so really cannot verify that it is the
> main problem atm. I was just curious because I know that such
> instructions exist for other processors.


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