Re: [PATCH] media: atomisp: silence "dubious: !x | !y" warning

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On Sat, Apr 17, 2021 at 09:31:32PM +0000, David Laight wrote:
> From: Mauro Carvalho Chehab
> > Sent: 17 April 2021 19:56
> > 
> > Em Sat, 17 Apr 2021 21:06:27 +0530
> > Ashish Kalra <eashishkalra@xxxxxxxxx> escreveu:
> > 
> > > Upon running sparse, "warning: dubious: !x | !y" is brought to notice
> > > for this file.  Logical and bitwise OR are basically the same in this
> > > context so it doesn't cause a runtime bug.  But let's change it to
> > > logical OR to make it cleaner and silence the Sparse warning.
> 
> The old code is very likely to by slightly more efficient.
> 
> It may not matter here, but it might in a really hot path.
> 
> Since !x | !y and !x || !y always have the same value
> why is sparse complaining at all.
> 

Smatch doesn't warn about | vs || if both sides are true/false.  But
I've occasionally asked people if they were trying to do a fast path
optimization but it's always just a typo.

regards,
dan carpenter

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