[trynumber9]

No, it was a third driver.

Per AMD

>Notably, AMD's closed-source Vulkan driver currently uses a different pipeline compiler, which is the major difference between AMD's open-source and closed-source Vulkan drivers.

[kimixa]

The windows driver has 2 paths, the internal compiler, and the same LLVM as in the open source amdvlk release (though there might be things like not-yet-upstreamed changes, experimental new hardware support etc. that differ from the public version, it was fundamentally the same codebase). The same for DX12 (and any other driver that might use their PAL layer). If you want to confirm you can see all the llvm symbols in the driver's amdvlk{32,64}.dll and amdxc{32,64}.dll files. From what I remember, the internal compiler path is just stripped out for the open source amdvlk releases.

I believe the intent was to slowly deprecate the internal closed compiler, and leave it more as a fallback for older hardware, with most new development happening on LLVM. Though my info is a few months out of date now, I'd be surprised if the trajectory changed that quickly.

[account42]

AFAIK the closed source shader compiler was/is also available for Linux in the amdgpu-pro package, just not in the open source releases.

[shmerl]

Why are they using different compilers?

[account42]

Either licensing issues (maybe they don't own all parts of the closed source shader compiler) or fears that Nvidia/Intel could find out things about the hardware that AMD wants to keep secret (the fears being Unfounded doesn't make the possibility of them being a reason any less likely). Or alternatively they considered it not worth releasing it (legal review isn't free) because the LLVM back-end was supposed to replace it anyway.

[jacquesm]

Bluntly: because they don't get software and never did. The hardware is actually pretty good but the software has always been terrible and it is a serious problem because NV sure could use some real competition.