Great! Only one last favor: I'd like llvmpipe to pass tests too. This needs two simple changes: * Despite its name, the coarse derivative can be fine, and in the case of llvmpipe it seems to be. So please quantize it like you do for the unqualified derivative. * llvmpipe is apparently even less precise than NVIDIA. So please raise the ULP limits like in https://gitlab.winehq.org/giomasce/vkd3d/-/commit/e78c53aab6be5cd647de25f47a....
That commit passes tests in all the implementations I have access to (radv, NVIDIA and Intel). If it is compiled in your mesa binaries, you can test on llvmpipe using `VKD3D_VULKAN_DEVICE=1` or something.
Also, we normally use the imperative form in commit subjects: "Support fine derivatives" rather than "Fine derivatives support". Thanks!