Re: float-to-short conversion

[CEL]

You are _NOT_ an idiot.
There were serious bugs in the generic implementation of several of the
type conversion kernels.

Best regards,
Marcus 
On Sun, 2019-11-17 at 12:20 -0500, Marcus D Leech wrote:
> Thanks Ron. 
> 
> I did some more testing, and it appears to indicate that I’m an
> idiot. I won’t go into the sordid details. 
> 
> 
> 
> Sent from my iPhone
> 
> > On Nov 17, 2019, at 6:17 AM, Ron Economos <address@hidden> wrote:
> > 
> > It's pretty easy to test for Volk issues. Just edit the
> > ~/.volk/volk_config file and change the volk_32f_s32f_convert_16i
> > line to generic for both alignments.
> > 
> > On my older box, volk_config has u_avx for both alignments (and
> > that works correctly).
> > 
> > Ron
> > 
> > > On 11/16/19 17:55, Marcus D. Leech wrote:
> > > Is it possible that at some point the GR3.7 float-to-short
> > > convert (which uses Volk, it seems) got busted?
> > > 
> > > I'm seeing values that look like they have been inappropriately
> > > byte-swapped.
> > > 
> > > The attached flow-graph produces an output file with the correct
> > > value of "7" interpreted as a Short, but when the same is run on
> > >   a different (still X86) machine (The Atom X5 z8350), as on the
> > > Atomic PI SBC, the values are byte-swapped.
> > > 
> > > I've been pulling my hair out for *weeks* on this, and only this
> > > evening came to realize that somewhere, those "shorts" are
> > > getting
> > >   byte-swapped, and it looks like *one* of the Volk kernels may
> > > be to blame.
> > > 
> > > I would fully-expect there to be "surprises" when exchanging data
> > > twixt ARM SBCs and any randomly-chosen X86, because some (not
> > > ALL)
> > >   ARMs use a different byte-ordering, but this is between X86
> > > systems.
> > > 
> > > And on my lappy, which is a core i7 m640, the attached flow-graph 
> > > produces the correct results in the output file.
> > > 
> > > My lappy is running GR 3.7.13.4 while the packaged GR for Ubuntu
> > > 18.04 (on the Atomic PI) is  3.7.11-10.
> > > 
> > > 
> > >

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