[Mesa-dev] [PATCH 2/2] i965: Avoid generating MOVs for most ir_assignment handling.

[Stéphane Marchesin]

On Sat, Aug 27, 2011 at 03:23, Kenneth Graunke <kenneth at whitecape.org> wrote:
> This is a port of vec4_visitor::try_rewrite_rhs_to_dst to fs_visitor.
>
> Not only is this technique less invasive and more robust, it also
> generates better code.  Over and above the previous technique, this
> reduced instruction count in shader-db:
>
> With all FS optimizations (register coalescing and such) disabled, this
> reduced instruction count by 6.23% on average and 36% in the best case.
>
> With optimizations left enabled, it still reduced instruction count by
> 0.28% on average and 1.4% in the best case.
>
> In no case did this technique result in more code than the prior method.
>

Hi,

This regresses yuv tests in glbench here. The shaders regressing are
the .glslf files there, and glbench can be found in the same repo:

http://git.chromium.org/gitweb/?p=chromiumos/third_party/autotest.git;a=tree;f=client/deps/glbench/src;h=8c533f2d21e87c143f512f693947d7a660c2b4bc;hb=HEAD

Stéphane