[lhl]

I started a project w/ the assumption that fully tuned for HIP kernels could get closer to roofline and beat llama.cpp's performance (and vs their ROCm engine it does!) but after thousands of iterations/experiments my suspicion is that RADV/ACO is actually just much better than LLVM/HIP when it comes to a lower-level scheduling etc for RDNA3.

I haven't finished comprehensive tests but I found:

- Vulkan is up to 2.25X faster for most coalesced, strided and interleave variants for memory-side scheduling/access shapes

- 3.3X faster on specific dot-path sweeps, including for scalar-dequant

- For matched LDS, Vulkan can be 8-14X+ faster (!!!) than matched HIP LDS

HIP doesn't always win against RADV/ACO, but on dispatch/runtime, it does appear to be quite a bit faster than HIP/LLVM on gfx1151 (Strix Halo). I'll be publishing sharing full data once I also run vs gfx1100...