Re: [PATCH 11/23] media: atomisp: Remove test pattern generator (TPG) support

[Kieran Bingham <kieran.bingham@ideasonboard.com>]

Quoting Kieran Bingham (2024-04-16 15:37:39)
> Quoting Andy Shevchenko (2024-04-16 14:34:45)
> > On Tue, Apr 16, 2024 at 12:25 PM Hans de Goede <hdegoede@redhat.com> wrote:
> > > On 4/15/24 4:40 PM, Andy Shevchenko wrote:
> > > > On Mon, Apr 15, 2024 at 02:02:08PM +0200, Hans de Goede wrote:
> > 
> > ...
> > 
> > > >>              unsigned int hblank_cycles = 100,
> > > >>              vblank_lines = 6,
> > > >>              width,
> > > >
> > > > Urgh... These comma operators probably is subject to replace with separate
> > > > definitions or being grouped on a single line (as it suppose to be in this
> > > > case).
> > >
> > > That indeed is ugly, but fixing this is out of scope for this patch,
> > > so I've added an extra patch to the set to address this:
> > >
> > > https://git.kernel.org/pub/scm/linux/kernel/git/hansg/linux.git/commit/?h=media-atomisp&id=48d93af9d9b0fd40a21a656cb8cd8e25700bfed5
> > 
> > WFM, thanks!
> > 
> > Btw (yes, I see you tagged that already, so just FYI then)
> > (1 + (stream->config.pixels_per_clock == 2));
> > is an interesting way of using
> > 
> >  (stream->config.pixels_per_clock == 2) ? 2 : 1);
> > 
> > which likely can produce slightly better code (due to use of constant
> > 2 twice), although it is a pure speculation by me.

Ooops, I didn't mean to send that. Well I wrote something but then
closed it when I wasn't going to bother and instead some how sent an
empty mail ..

So now I guess I should actually say what I wasn't going to end up
saying? haha.

This was too intriguing (to me) so I threw it in godbolt, and for
various levels of compiler optimsations, both options generate the same
code, even with -O0. Of course the different optimsation levels produce
different code, but the two options above always match at the given
level.

Fun with godbolt ;-)

https://godbolt.org/z/hYjrvK6hn

> > 
> > -- 
> > With Best Regards,
> > Andy Shevchenko