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

[Trond Danielsen]

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.

--
Trond Danielsen