Add the PivCo-Huffman encode/decode kernels (#849)#849
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Summary:
Implements the Huffman Pivoted kernel on top of the architecture kernel interface.
`common_pivoted_kernel.{h,c}` provides the shared coding tree `ZL_HuffmanPivotedTree`, and is the core of the algorithm. Both encoding and decoding are just doing a pre-order traversal over this tree, and following the instructions given.
`decode_pivoted_kernel.{h,c}` provides `ZL_HuffmanPivoted_decode`, and the core compexity is in `decodeNode`.
`encode_pivoted_kernel.{h,c}` provides `ZL_HuffmanPivoted_encode`, and the core complexity is in `encodeNode`
Differential Revision: D109882916
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Summary:
Implements the Huffman Pivoted kernel on top of the architecture kernel interface.
`common_pivoted_kernel.{h,c}` provides the shared coding tree `ZL_HuffmanPivotedTree`, and is the core of the algorithm. Both encoding and decoding are just doing a pre-order traversal over this tree, and following the instructions given.
`decode_pivoted_kernel.{h,c}` provides `ZL_HuffmanPivoted_decode`, and the core compexity is in `decodeNode`.
`encode_pivoted_kernel.{h,c}` provides `ZL_HuffmanPivoted_encode`, and the core complexity is in `encodeNode`
Differential Revision: D109882916
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Summary:
Implements the Huffman Pivoted kernel on top of the architecture kernel interface.
`common_pivoted_kernel.{h,c}` provides the shared coding tree `ZL_HuffmanPivotedTree`, and is the core of the algorithm. Both encoding and decoding are just doing a pre-order traversal over this tree, and following the instructions given.
`decode_pivoted_kernel.{h,c}` provides `ZL_HuffmanPivoted_decode`, and the core compexity is in `decodeNode`.
`encode_pivoted_kernel.{h,c}` provides `ZL_HuffmanPivoted_encode`, and the core complexity is in `encodeNode`
Differential Revision: D109882916
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Summary:
Implements the Huffman Pivoted kernel on top of the architecture kernel interface.
`common_pivoted_kernel.{h,c}` provides the shared coding tree `ZL_HuffmanPivotedTree`, and is the core of the algorithm. Both encoding and decoding are just doing a pre-order traversal over this tree, and following the instructions given.
`decode_pivoted_kernel.{h,c}` provides `ZL_HuffmanPivoted_decode`, and the core compexity is in `decodeNode`.
`encode_pivoted_kernel.{h,c}` provides `ZL_HuffmanPivoted_encode`, and the core complexity is in `encodeNode`
Differential Revision: D109882916
Summary: See https://www.internalfb.com/code/fbsource/[0b9e4a2588b4f716d3259505ea591a25cea158a1]/fbcode/folly/CpuId.h?lines=155-164 Reviewed By: daniellerozenblit Differential Revision: D109877948
Summary: As title Reviewed By: daniellerozenblit Differential Revision: D109877947
Summary: Adds byte-aligned bit reservation and pop primitives to the FF bitstream, needed by the upcoming PivCo-Huffman kernels: - `ZS_BitCStreamFF_reserveAlignedBits` / `ZS_BitCStreamFF_commitReservedBits` on the write side. - `ZS_BitDStreamFF_popAlignedBits` on the read side, plus a `begin` cursor in `ZS_BitDStreamFF` so the reader can compute byte offsets. - `ZS_BitDStreamFF_finish` now returns the number of bytes consumed. - Hardens `ZS_BitCStreamFF_init`/`_finish`/`_flush` against small buffers by avoiding pointer arithmetic that could underflow. Differential Revision: D109878843
Summary: Introduces the architecture-specific kernel interface for the PivCo-Huffman codec along with a portable, correctness-oriented generic implementation and the kernel test suite. The `ZL_PivCoHuffmanEncode` and `ZL_PivCoHuffmanDecode` structs provide the interface to cleanly swap between implementations based on the CPU. The `select()` function will pick the best implementation based on the current CPU, when they are added, but for now just returns the generic implementation. These are the kernels defined in the [PivCo Huffman paper](https://arxiv.org/pdf/2606.05765). The only difference is the encode side is modified following the same strategy as the [upstream repo](https://github.com/MarcinZukowski/pivco-huffman) to operate on `uint8_t rank` values, rather than `uint16_t codeword` values. The reasoning for how that change work is explained in the next diff, but the benefit is working on `uint8_t` instead of `uint16_t`. Note that some buffers require `SLOP` bytes at the end, and `partitionFull` has an odd aliasing requirement. These are constraints that are imposed by the full implementation in the next diff. Differential Revision: D109878842
Summary: Adds `micro_pivco_huffman.cpp` and wires it into the micro benchmark harness (`micro_bench.{cpp,h}`) to measure the PivCo-Huffman encode/decode kernels.
Differential Revision: D110077474
Summary:
Implements the PivCo-Huffman kernel on top of the architecture kernel interface.
`common_pivco_kernel.{h,c}` provides the shared coding tree `ZL_PivCoHuffmanTree`, and is the core of the algorithm. Both encoding and decoding are just doing a pre-order traversal over this tree, and following the instructions given.
`decode_pivco_kernel.{h,c}` provides `ZL_PivCoHuffman_decode`, and the core compexity is in `decodeNode`.
`encode_pivco_kernel.{h,c}` provides `ZL_PivCoHuffman_encode`, and the core complexity is in `encodeNode`
Differential Revision: D109882916
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Summary:
Implements the PivCo-Huffman kernel on top of the architecture kernel interface.
common_pivco_kernel.{h,c}provides the shared coding treeZL_PivCoHuffmanTree, and is the core of the algorithm. Both encoding and decoding are just doing a pre-order traversal over this tree, and following the instructions given.decode_pivco_kernel.{h,c}providesZL_PivCoHuffman_decode, and the core compexity is indecodeNode.encode_pivco_kernel.{h,c}providesZL_PivCoHuffman_encode, and the core complexity is inencodeNodeDifferential Revision: D109882916