Mesa 21.3.3 Released With Fixes For Old ATI R300~R500 GPUs, RADV Fixes Too

For those sticking to stable Mesa point releases, Mesa 21.3.3 is out today to close out the year. Notable with Mesa 21.3.3 is the large number of fixes for older ATI Radeon R300 through R500 (X1000 series) GPU fixes with the R300 Gallium3D driver.

Exciting vintage GPU enthusiasts earlier this month was word of a big performance optimization for R300 Gallium3D with that old open-source OpenGL driver for Radeon 9500 through X1000 series graphics cards. That work revolved around NIR-to-TGSI path for making use of the intermediate representation preferred by newer Mesa drivers. Those changes are in Mesa 22.0 for next quarter's stable release and not the current 21.3 stable series.

While lacking the hefty NIR work for R300g, Mesa 21.3.3 does bring a number of fixes for that old Gallium3D driver from the ATI days. There are some optimization fixes, various instruction changes, disabling loop unrolling on R600 GPUs, and some vertex shader fixes. The disabling of loop unrolling on R500 was done as the code was found to be rather buggy so instead rely on GLSL or NIR for loop unrolling. These fixes are mostly minor while those still using the nearly two decade old Radeon GPUs will be eager for Mesa 22.0's debut in February~March.

Both new and old Radeon GPUs benefit from this new open-source Mesa 3D update.

Aside from the R300g fixes, there are also fixes for newer Radeon GPUs with several RADV Vulkan driver fixes. There are also ACO compiler back-end fixes too.

The rest of the Mesa 21.3.3 changes include fixes for Panfrost, GLSL, fixing building of OpenSWR under MSVC, and one Intel fix. The full list of patches can be found via the announcement.