radv,nir: optimize vkd3d-proton's MSAD instruction
Apparently this DXIL instruction is used by FSR 3. The unoptimized sequence is horrible, but I don't know how much of an effect this has on actual FSR 3 shaders.
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Apparently this DXIL instruction is used by FSR 3. The unoptimized sequence is horrible, but I don't know how much of an effect this has on actual FSR 3 shaders.