[Mesa-dev] [PATCH] nir: Add a couple of iand/ior optimizations

[Jason Ekstrand]

On Tue, Jul 24, 2018 at 5:41 PM Timothy Arceri <tarceri at itsqueeze.com>
wrote:

> On 24/07/18 00:10, Jason Ekstrand wrote:
> > On Mon, Jul 23, 2018 at 1:08 AM Timothy Arceri <tarceri at itsqueeze.com
> > <mailto:tarceri at itsqueeze.com>> wrote:
> >
> >     Ian and I have been looking at these type of things recently. Ian has
> >     started work on a pass to cover this stuff without having to add
> dozens
> >     of these types of opts.
> >
> >
> https://lists.freedesktop.org/archives/mesa-dev/2018-July/200583.html
> >
> >
> > Does said pass work only on logical operations with booleans or also
> > regular bitwise operations?  This patch is for bitwise operations though
> > it naturally works with booleans.
>
> Good point. I replied to this too quickly without thinking too hard. In
> that case we should probably also add these similar opt which I have
> also come across:
>
>     (('ior', ('ior', a, b), a), ('ior', a, b)),
>     (('iand', ('iand', a, b), a), ('iand', a, b)),
>

Done.


> With those added:
>
> Reviewed-by: Timothy Arceri <tarceri at itsqueeze.com>
>

Thanks!


> >
> > --Jason
> >
> >     On 23/07/18 17:36, Jason Ekstrand wrote:
> >      > Spotted in a shader in Batman: Arkham City.
> >      > ---
> >      >   src/compiler/nir/nir_opt_algebraic.py | 2 ++
> >      >   1 file changed, 2 insertions(+)
> >      >
> >      > diff --git a/src/compiler/nir/nir_opt_algebraic.py
> >     b/src/compiler/nir/nir_opt_algebraic.py
> >      > index ba277fdfd0e..f2007852b21 100644
> >      > --- a/src/compiler/nir/nir_opt_algebraic.py
> >      > +++ b/src/compiler/nir/nir_opt_algebraic.py
> >      > @@ -377,6 +377,8 @@ optimizations = [
> >      >      (('ixor', a, a), 0),
> >      >      (('ixor', a, 0), a),
> >      >      (('inot', ('inot', a)), a),
> >      > +   (('ior', ('iand', a, b), b), b),
> >      > +   (('iand', ('ior', a, b), b), b),
> >      >      # DeMorgan's Laws
> >      >      (('iand', ('inot', a), ('inot', b)), ('inot', ('ior',  a,
> b))),
> >      >      (('ior',  ('inot', a), ('inot', b)), ('inot', ('iand', a,
> b))),
> >      >
> >
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/mesa-dev/attachments/20180724/11a4367d/attachment.html>