OpenGL 4 Shader Image Extensions Land Today In RadeonSI Gallium3D

There are some notable improvements that landed today in RadeonSI Gallium3D for AMD GCN graphics processors.

The highlights from the work that landed in Mesa Git today for RadeonSI include:

- Coherent memory access.

- Volatile memory access.

- Memory barriers.

- The many patches culminate with two GL4 extensions being done. ARB_shader_image_load_store and ARB_shader_image_size are now complete for RadeonSI! Up to now, only the i965 Intel driver supported these extensions for OpenGL 4.2 and 4.3, respectively.

Kudos to Nicolai Hähnle and the others involved in this shader image extension support! This now leaves RadeonSI with needing ARB_shader_atomic_counters before having OpenGL 4.2 support, which shouldn't be too far out considering core Mesa and the Intel / Nouveau NVC0 drivers already support this extension. We're still then several extensions away from official OpenGL 4.3 support. Or fire up the new "PRO" hybrid driver if you want OpenGL 4.5 today.