vulkan: warptiles currently assume warp sizes <= 64, clamp to work around larger warps - #27726
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| const uint32_t subgroup_size_32 = std::max(device->subgroup_size, 32u); | ||
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| // clamp WARP for l_/m_ warptiles so WM <= BM (breaks on subgroupSize > 64) | ||
| const uint32_t mm_warp_8 = std::min(subgroup_size_8, 64u); |
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I've never fully understood these tile size calculations. Would this work for a coopmat implementation with subgroupSize==128?
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With coopmat it may be problematic, but currently the tile sizes are just incompatible generally with subgroups > 64. It was all created for subgroup size 32/64 on Nvidia and AMD.
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…ound larger warps (ggml-org#27726)
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Overview
Fixes #25734, supersedes #25735 which missed a few clamps. Long term, Adreno-compatible tiles could be added once #25773 is done.
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