Valve's ACO Shader Compiler Under Review For The Mesa Radeon Vulkan Driver

The RADV "ACO" shader compiler announced by Valve back in July for the fastest compilation speeds and best possible code generation may soon be hitting mainline Mesa for the open-source AMD Linux graphics stack.

The ACO shader compiler as an alternative to the existing AMDGPU LLVM shader compiler back-end has shown quite promising results for Linux games. ACO has become more featureful over time and is now largely at feature parity to the existing shader compilation support while generally offering some performance advantages, thanks to the effort and funding by Valve.

Opened on Tuesday was a merge request for adding the ACO shader compiler to the Mesa code-base for the RADV Vulkan driver. There's been talk of extending ACO to the RadeonSI OpenGL driver too, but at least at this time the changes are just about the Mesa Radeon Vulkan driver.

The code is still undergoing review so it's not mainlined yet, but hopefully we'll see this become an option for next quarter's Mesa 19.3 release. More benchmarks will come when ACO is merged though initially at least it may not be running at its full performance due to some related NIR changes still pending as well.

Update: It's merged!