[Mesa-dev] [PATCH 09/23] i965/vs: Map scalar VS input locations properly; avoid tons of MOVs.

[Matt Turner]

On Wed, Sep 30, 2015 at 12:58 AM, Kenneth Graunke <kenneth at whitecape.org> wrote:
> Previously, we used nir_lower_io with the scalar type_size function,
> which mapped VERT_ATTRIB_* locations to...some numbers.  Then, in
> fs_visitor::nir_setup_inputs(), we created temporaries indexed by
> those numbers, and emitted MOVs from the actual ATTR registers to
> those temporaries.
>
> This patch reworks our input lowering to produce NIR lower_input
> intrinsics that properly index into the ATTR file, so we can access
> it directly.
>
> No changes in shader-db.

You  might add a sentence here that explains that this patch lets the
driver avoid generating a bunch of MOVs that would otherwise be
optimized away. The contrasting "avoid tons of MOVs" and "No changes
in shader-db" might be confusing otherwise.