VMware's SVGA Gallium3D Driver Getting NIR'ed

Following the open-source NVIDIA "Nouveau" driver switching to NIR by default, the VMware SVGA Gallium3D driver has also landed NIR-to-TGSI support in mainline.

Emma Anholt has been leading the work on gutting Mesa of the old GLSL-to-TGSI path and moving all drivers to ultimately go through the NIR intermediate representation even if it means translating back to TGSI at the end. Getting rid of GLSL-to-TGSI allows removing lots of old, poorly maintained code. Getting the drivers using the NIR intermediate representation is a win for performance as well.

The latest step in that quest is allowing VMware's SVGA Gallium3D driver to allow requesting NIR and translating to TGSI. As of Wednesday that SVGA code has been merged into Mesa 22.2 to clear that hurdle and another step closer to the GLSL-to-TGSI deletion.

While for now the SVGA driver still has to rely on NIR-to-TGSI, VMware is working on plumbing native NIR support into the driver. It was mentioned in the merge request that VMware engineers are working on native NIR support for this Gallium3D driver and they hope to have that integration completed roughly around mid-year. So shortly that extra step of going back to TGSI in SVGA should be avoided for further improving this open-source driver used for virtual GPU support with VMware virtualization software.