[ET-VK][refactor] Introduce PackedDimInfo struct for packed dimension metadata #16414
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… metadata Pull Request resolved: #16403 ## Context With the introduction of block-packed memory layouts for quantized tensors, the metadata stored by `vTensor` used to describe the data layout within a texture/buffer was no longer sufficient to form a complete description of the data layout. This created an awkward pattern of needing to estimate the `GPUMemoryLayout` which would be needed to compute storage descriptors such as image extents. This diff addresses the problem by introducing the `PackedDimInfo` struct to `vTensor`, which provides a complete description of how data in a tensor may be organized in the GPU buffer/texture used to store the tensor data, and allows simplification of the functions used to compute buffer numel or texture extents. ## `PackedDimInfo` Introduced the `PackedDimInfo` struct that encapsulates all information about packed dimensions in GPU tensors. This improves code organization and makes the relationship between related metadata fields explicit. The `PackedDimInfo` struct contains: - `packed_dim`: Which dimension is tightly packed (WHCN index) / contiguous in memory - `packed_dim_padded`: Whether the packed dimension is padded to multiple of 4; some layouts will do this to accomodate vectorized load/stores - `outer_packed_dim`: Second-level packing for block-packed layouts (4W4C, 4H4W); for layouts with only a single level of packing, will be equal to `packed_dim` - `outer_packed_dim_padded`: Whether outer packed dim is padded (tiled only) ## Changes - Added PackedDimInfo struct with helper function calculate_packed_dim_info() - Replaced packed_dim_ member with packed_dim_info_ in vTensor class - Updated function signatures to accept PackedDimInfo& instead of packed_dim_: * create_hashed_layout * calculate_dim_order * calculate_padded_sizes * calculate_logical_limits * TextureMetadata constructor/update * vTensorStorage constructor - Added packed_dim_info() accessor to vTensor and ComputeGraph classes - Store an additional `padded_sizes_` member in vTensor which is now used to for strides/image extents/GPU buffer numel computation, instead of using `sizes_` directly - Introduce memory layouts for kInt8x4 type that only use a single level of packing ghstack-source-id: 331381718 Differential Revision: [D89832382](https://our.internmc.facebook.com/intern/diff/D89832382/)
🔗 Helpful Links🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/16414
Note: Links to docs will display an error until the docs builds have been completed. ❗ 1 Active SEVsThere are 1 currently active SEVs. If your PR is affected, please view them below: ⏳ No Failures, 133 PendingAs of commit 447d2a4 with merge base 0dfda64 ( This comment was automatically generated by Dr. CI and updates every 15 minutes. |
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This PR was created by the merge bot to help merge the original PR into the main branch.
ghstack PR number: #16403 by @SS-JIA
^ Please use this as the source of truth for the PR details, comments, and reviews
ghstack PR base: https://github.com/pytorch/executorch/tree/gh/SS-JIA/388/base
ghstack PR head: https://github.com/pytorch/executorch/tree/gh/SS-JIA/388/head
Merge bot PR base: https://github.com/pytorch/executorch/tree/main
Merge bot PR head: https://github.com/pytorch/executorch/tree/gh/SS-JIA/388/orig
Differential Revision: D89832382
@diff-train-skip-merge