/* * Copyright (c) Meta Platforms, Inc. and affiliates. * All rights reserved. * * This source code is licensed under both the BSD-style license (found in the * LICENSE file in the root directory of this source tree) and the GPLv2 (found * in the COPYING file in the root directory of this source tree). * You may select, at your option, one of the above-listed licenses. */ /*-************************************* * Dependencies ***************************************/ #include "zstd_compress_superblock.h" #include "../common/zstd_internal.h" /* ZSTD_getSequenceLength */ #include "hist.h" /* HIST_countFast_wksp */ #include "zstd_compress_internal.h" /* ZSTD_[huf|fse|entropy]CTablesMetadata_t */ #include "zstd_compress_sequences.h" #include "zstd_compress_literals.h" /** ZSTD_compressSubBlock_literal() : * Compresses literals section for a sub-block. * When we have to write the Huffman table we will sometimes choose a header * size larger than necessary. This is because we have to pick the header size * before we know the table size + compressed size, so we have a bound on the * table size. If we guessed incorrectly, we fall back to uncompressed literals. * * We write the header when writeEntropy=1 and set entropyWritten=1 when we succeeded * in writing the header, otherwise it is set to 0. * * hufMetadata->hType has literals block type info. * If it is set_basic, all sub-blocks literals section will be Raw_Literals_Block. * If it is set_rle, all sub-blocks literals section will be RLE_Literals_Block. * If it is set_compressed, first sub-block's literals section will be Compressed_Literals_Block * If it is set_compressed, first sub-block's literals section will be Treeless_Literals_Block * and the following sub-blocks' literals sections will be Treeless_Literals_Block. * @return : compressed size of literals section of a sub-block * Or 0 if unable to compress. * Or error code */ static size_t ZSTD_compressSubBlock_literal(const HUF_CElt* hufTable, const ZSTD_hufCTablesMetadata_t* hufMetadata, const BYTE* literals, size_t litSize, void* dst, size_t dstSize, const int bmi2, int writeEntropy, int* entropyWritten) { … } static size_t ZSTD_seqDecompressedSize(seqStore_t const* seqStore, const seqDef* sequences, size_t nbSeqs, size_t litSize, int lastSubBlock) { … } /** ZSTD_compressSubBlock_sequences() : * Compresses sequences section for a sub-block. * fseMetadata->llType, fseMetadata->ofType, and fseMetadata->mlType have * symbol compression modes for the super-block. * The first successfully compressed block will have these in its header. * We set entropyWritten=1 when we succeed in compressing the sequences. * The following sub-blocks will always have repeat mode. * @return : compressed size of sequences section of a sub-block * Or 0 if it is unable to compress * Or error code. */ static size_t ZSTD_compressSubBlock_sequences(const ZSTD_fseCTables_t* fseTables, const ZSTD_fseCTablesMetadata_t* fseMetadata, const seqDef* sequences, size_t nbSeq, const BYTE* llCode, const BYTE* mlCode, const BYTE* ofCode, const ZSTD_CCtx_params* cctxParams, void* dst, size_t dstCapacity, const int bmi2, int writeEntropy, int* entropyWritten) { … } /** ZSTD_compressSubBlock() : * Compresses a single sub-block. * @return : compressed size of the sub-block * Or 0 if it failed to compress. */ static size_t ZSTD_compressSubBlock(const ZSTD_entropyCTables_t* entropy, const ZSTD_entropyCTablesMetadata_t* entropyMetadata, const seqDef* sequences, size_t nbSeq, const BYTE* literals, size_t litSize, const BYTE* llCode, const BYTE* mlCode, const BYTE* ofCode, const ZSTD_CCtx_params* cctxParams, void* dst, size_t dstCapacity, const int bmi2, int writeLitEntropy, int writeSeqEntropy, int* litEntropyWritten, int* seqEntropyWritten, U32 lastBlock) { … } static size_t ZSTD_estimateSubBlockSize_literal(const BYTE* literals, size_t litSize, const ZSTD_hufCTables_t* huf, const ZSTD_hufCTablesMetadata_t* hufMetadata, void* workspace, size_t wkspSize, int writeEntropy) { … } static size_t ZSTD_estimateSubBlockSize_symbolType(symbolEncodingType_e type, const BYTE* codeTable, unsigned maxCode, size_t nbSeq, const FSE_CTable* fseCTable, const U8* additionalBits, short const* defaultNorm, U32 defaultNormLog, U32 defaultMax, void* workspace, size_t wkspSize) { … } static size_t ZSTD_estimateSubBlockSize_sequences(const BYTE* ofCodeTable, const BYTE* llCodeTable, const BYTE* mlCodeTable, size_t nbSeq, const ZSTD_fseCTables_t* fseTables, const ZSTD_fseCTablesMetadata_t* fseMetadata, void* workspace, size_t wkspSize, int writeEntropy) { … } EstimatedBlockSize; static EstimatedBlockSize ZSTD_estimateSubBlockSize(const BYTE* literals, size_t litSize, const BYTE* ofCodeTable, const BYTE* llCodeTable, const BYTE* mlCodeTable, size_t nbSeq, const ZSTD_entropyCTables_t* entropy, const ZSTD_entropyCTablesMetadata_t* entropyMetadata, void* workspace, size_t wkspSize, int writeLitEntropy, int writeSeqEntropy) { … } static int ZSTD_needSequenceEntropyTables(ZSTD_fseCTablesMetadata_t const* fseMetadata) { … } static size_t countLiterals(seqStore_t const* seqStore, const seqDef* sp, size_t seqCount) { … } #define BYTESCALE … static size_t sizeBlockSequences(const seqDef* sp, size_t nbSeqs, size_t targetBudget, size_t avgLitCost, size_t avgSeqCost, int firstSubBlock) { … } /** ZSTD_compressSubBlock_multi() : * Breaks super-block into multiple sub-blocks and compresses them. * Entropy will be written into the first block. * The following blocks use repeat_mode to compress. * Sub-blocks are all compressed, except the last one when beneficial. * @return : compressed size of the super block (which features multiple ZSTD blocks) * or 0 if it failed to compress. */ static size_t ZSTD_compressSubBlock_multi(const seqStore_t* seqStorePtr, const ZSTD_compressedBlockState_t* prevCBlock, ZSTD_compressedBlockState_t* nextCBlock, const ZSTD_entropyCTablesMetadata_t* entropyMetadata, const ZSTD_CCtx_params* cctxParams, void* dst, size_t dstCapacity, const void* src, size_t srcSize, const int bmi2, U32 lastBlock, void* workspace, size_t wkspSize) { … } size_t ZSTD_compressSuperBlock(ZSTD_CCtx* zc, void* dst, size_t dstCapacity, const void* src, size_t srcSize, unsigned lastBlock) { … }
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