Gallium3D's Nouveau Lands ARB_compute_variable_group_size Implementation

Thanks to the ongoing compute-focused work by independent Nouveau contributor Samuel Pitoiset, the NVC0 Gallium3D driver is the first driver in Mesa supporting the ARB_compute_variable_group_size extension.

ARB_compute_variable_group_size extension is yet to be part of any official OpenGL specification release. As described via the OpenGL.org registry, "This extension allows applications to write generic compute shaders that operate on work groups with arbitrary dimensions. Instead of specifying a fixed work group size in the compute shader, an application can use a compute shader using the /local_size_variable/ layout qualifer to indicate a variable work group size."

Samuel landed the several patches yesterday for prepping GLAPI/GLSL for this extension plus exposing it in the Mesa state tracker and then ensuring it works for the NVC0 driver (NVIDIA Fermi and newer hardware) then marking it as complete.

Yet another extension to mark off the list for Nouveau NVC0 with this upcoming Mesa release due out in the next few weeks. One week to go until the feature freeze.