Renewed Work For ACO Compiler Support With The RadeonSI Gallium3D Driver

Back in 2019 Valve developers introduced the ACO compiler back-end within Mesa for the Radeon Vulkan "RADV" driver. This alternative to the AMDGPU LLVM shader compiler has been instrumental in helping RADV perform very well for Linux gaming both with Vulkan native titles as well as games going the route of DirectX to Vulkan via DXVK and VKD3D with Proton (Steam Play). On and off there's been talk and work towards bringing ACO to RadeonSI Gallium3D for OpenGL while now there is some new work on this front.

Going back to when ACO first debuted by Valve, there's been talk and interest in seeing ACO compiler support for the RadeonSI driver. However, with time more Linux-native games have adopted Vulkan and with the success of Steam Play and DXVK/VKD3D(-Proton) via the Vulkan API, these days there is much less concern for OpenGL with Linux gaming. Plus the RadeonSI Gallium3D driver is already quite well optimized for AMD GPUs. Additionally, RadeonSI is maintained by AMD engineers and they continue to focus on the AMDGPU LLVM shader compiler back-end across platforms. Meanwhile ACO is primarily a product of Valve engineers.

From time to time there is ACO talk/developments for RadeonSI and again this week that happened. Qiang Yu opened a new merge request entitled aco: prepare for radeonsi usage. The new merge request contains the "changes are for RadeonSI monolithic PS to use ACO." That followed this additional MR with more RadeonSI changes in preparation.

There also is still other related work outstanding like this six month old merge request to remove the RADV dependency for ACO so that it can be more easily used with RadeonSI. We'll see where this latest RadeonSI ACO work leads and the level of interest in ACO support with RadeonSI.