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Diffstat (limited to 'lib/zstd/huf_decompress.c')
| -rw-r--r-- | lib/zstd/huf_decompress.c | 930 |
1 files changed, 930 insertions, 0 deletions
diff --git a/lib/zstd/huf_decompress.c b/lib/zstd/huf_decompress.c new file mode 100644 index 0000000000..97145b0608 --- /dev/null +++ b/lib/zstd/huf_decompress.c @@ -0,0 +1,930 @@ +// SPDX-License-Identifier: (GPL-2.0 or BSD-2-Clause) +/* + * Huffman decoder, part of New Generation Entropy library + * Copyright (C) 2013-2016, Yann Collet. + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ + +/* ************************************************************** +* Compiler specifics +****************************************************************/ +#define FORCE_INLINE static __always_inline + +/* ************************************************************** +* Dependencies +****************************************************************/ +#include "bitstream.h" /* BIT_* */ +#include "fse.h" /* header compression */ +#include "huf.h" +#include <linux/compiler.h> +#include <linux/kernel.h> +#include <linux/string.h> /* memcpy, memset */ + +/* ************************************************************** +* Error Management +****************************************************************/ +#define HUF_STATIC_ASSERT(c) \ + { \ + enum { HUF_static_assert = 1 / (int)(!!(c)) }; \ + } /* use only *after* variable declarations */ + +/*-***************************/ +/* generic DTableDesc */ +/*-***************************/ + +typedef struct { + BYTE maxTableLog; + BYTE tableType; + BYTE tableLog; + BYTE reserved; +} DTableDesc; + +static DTableDesc HUF_getDTableDesc(const HUF_DTable *table) +{ + DTableDesc dtd; + memcpy(&dtd, table, sizeof(dtd)); + return dtd; +} + +/*-***************************/ +/* single-symbol decoding */ +/*-***************************/ + +typedef struct { + BYTE byte; + BYTE nbBits; +} HUF_DEltX2; /* single-symbol decoding */ + +size_t HUF_readDTableX2_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize) +{ + U32 tableLog = 0; + U32 nbSymbols = 0; + size_t iSize; + void *const dtPtr = DTable + 1; + HUF_DEltX2 *const dt = (HUF_DEltX2 *)dtPtr; + + U32 *rankVal; + BYTE *huffWeight; + size_t spaceUsed32 = 0; + + rankVal = (U32 *)workspace + spaceUsed32; + spaceUsed32 += HUF_TABLELOG_ABSOLUTEMAX + 1; + huffWeight = (BYTE *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(tableLog_tooLarge); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + + HUF_STATIC_ASSERT(sizeof(DTableDesc) == sizeof(HUF_DTable)); + /* memset(huffWeight, 0, sizeof(huffWeight)); */ /* is not necessary, even though some analyzer complain ... */ + + iSize = HUF_readStats_wksp(huffWeight, HUF_SYMBOLVALUE_MAX + 1, rankVal, &nbSymbols, &tableLog, src, srcSize, workspace, workspaceSize); + if (HUF_isError(iSize)) + return iSize; + + /* Table header */ + { + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (tableLog > (U32)(dtd.maxTableLog + 1)) + return ERROR(tableLog_tooLarge); /* DTable too small, Huffman tree cannot fit in */ + dtd.tableType = 0; + dtd.tableLog = (BYTE)tableLog; + memcpy(DTable, &dtd, sizeof(dtd)); + } + + /* Calculate starting value for each rank */ + { + U32 n, nextRankStart = 0; + for (n = 1; n < tableLog + 1; n++) { + U32 const curr = nextRankStart; + nextRankStart += (rankVal[n] << (n - 1)); + rankVal[n] = curr; + } + } + + /* fill DTable */ + { + U32 n; + for (n = 0; n < nbSymbols; n++) { + U32 const w = huffWeight[n]; + U32 const length = (1 << w) >> 1; + U32 u; + HUF_DEltX2 D; + D.byte = (BYTE)n; + D.nbBits = (BYTE)(tableLog + 1 - w); + for (u = rankVal[w]; u < rankVal[w] + length; u++) + dt[u] = D; + rankVal[w] += length; + } + } + + return iSize; +} + +static BYTE HUF_decodeSymbolX2(BIT_DStream_t *Dstream, const HUF_DEltX2 *dt, const U32 dtLog) +{ + size_t const val = BIT_lookBitsFast(Dstream, dtLog); /* note : dtLog >= 1 */ + BYTE const c = dt[val].byte; + BIT_skipBits(Dstream, dt[val].nbBits); + return c; +} + +#define HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) *ptr++ = HUF_decodeSymbolX2(DStreamPtr, dt, dtLog) + +#define HUF_DECODE_SYMBOLX2_1(ptr, DStreamPtr) \ + if (ZSTD_64bits() || (HUF_TABLELOG_MAX <= 12)) \ + HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) + +#define HUF_DECODE_SYMBOLX2_2(ptr, DStreamPtr) \ + if (ZSTD_64bits()) \ + HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) + +FORCE_INLINE size_t HUF_decodeStreamX2(BYTE *p, BIT_DStream_t *const bitDPtr, BYTE *const pEnd, const HUF_DEltX2 *const dt, const U32 dtLog) +{ + BYTE *const pStart = p; + + /* up to 4 symbols at a time */ + while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p <= pEnd - 4)) { + HUF_DECODE_SYMBOLX2_2(p, bitDPtr); + HUF_DECODE_SYMBOLX2_1(p, bitDPtr); + HUF_DECODE_SYMBOLX2_2(p, bitDPtr); + HUF_DECODE_SYMBOLX2_0(p, bitDPtr); + } + + /* closer to the end */ + while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p < pEnd)) + HUF_DECODE_SYMBOLX2_0(p, bitDPtr); + + /* no more data to retrieve from bitstream, hence no need to reload */ + while (p < pEnd) + HUF_DECODE_SYMBOLX2_0(p, bitDPtr); + + return pEnd - pStart; +} + +static size_t HUF_decompress1X2_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + BYTE *op = (BYTE *)dst; + BYTE *const oend = op + dstSize; + const void *dtPtr = DTable + 1; + const HUF_DEltX2 *const dt = (const HUF_DEltX2 *)dtPtr; + BIT_DStream_t bitD; + DTableDesc const dtd = HUF_getDTableDesc(DTable); + U32 const dtLog = dtd.tableLog; + + { + size_t const errorCode = BIT_initDStream(&bitD, cSrc, cSrcSize); + if (HUF_isError(errorCode)) + return errorCode; + } + + HUF_decodeStreamX2(op, &bitD, oend, dt, dtLog); + + /* check */ + if (!BIT_endOfDStream(&bitD)) + return ERROR(corruption_detected); + + return dstSize; +} + +size_t HUF_decompress1X2_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (dtd.tableType != 0) + return ERROR(GENERIC); + return HUF_decompress1X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable *DCtx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + const BYTE *ip = (const BYTE *)cSrc; + + size_t const hSize = HUF_readDTableX2_wksp(DCtx, cSrc, cSrcSize, workspace, workspaceSize); + if (HUF_isError(hSize)) + return hSize; + if (hSize >= cSrcSize) + return ERROR(srcSize_wrong); + ip += hSize; + cSrcSize -= hSize; + + return HUF_decompress1X2_usingDTable_internal(dst, dstSize, ip, cSrcSize, DCtx); +} + +static size_t HUF_decompress4X2_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + /* Check */ + if (cSrcSize < 10) + return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */ + + { + const BYTE *const istart = (const BYTE *)cSrc; + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstSize; + const void *const dtPtr = DTable + 1; + const HUF_DEltX2 *const dt = (const HUF_DEltX2 *)dtPtr; + + /* Init */ + BIT_DStream_t bitD1; + BIT_DStream_t bitD2; + BIT_DStream_t bitD3; + BIT_DStream_t bitD4; + size_t const length1 = ZSTD_readLE16(istart); + size_t const length2 = ZSTD_readLE16(istart + 2); + size_t const length3 = ZSTD_readLE16(istart + 4); + size_t const length4 = cSrcSize - (length1 + length2 + length3 + 6); + const BYTE *const istart1 = istart + 6; /* jumpTable */ + const BYTE *const istart2 = istart1 + length1; + const BYTE *const istart3 = istart2 + length2; + const BYTE *const istart4 = istart3 + length3; + const size_t segmentSize = (dstSize + 3) / 4; + BYTE *const opStart2 = ostart + segmentSize; + BYTE *const opStart3 = opStart2 + segmentSize; + BYTE *const opStart4 = opStart3 + segmentSize; + BYTE *op1 = ostart; + BYTE *op2 = opStart2; + BYTE *op3 = opStart3; + BYTE *op4 = opStart4; + U32 endSignal; + DTableDesc const dtd = HUF_getDTableDesc(DTable); + U32 const dtLog = dtd.tableLog; + + if (length4 > cSrcSize) + return ERROR(corruption_detected); /* overflow */ + { + size_t const errorCode = BIT_initDStream(&bitD1, istart1, length1); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD2, istart2, length2); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD3, istart3, length3); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD4, istart4, length4); + if (HUF_isError(errorCode)) + return errorCode; + } + + /* 16-32 symbols per loop (4-8 symbols per stream) */ + endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4); + for (; (endSignal == BIT_DStream_unfinished) && (op4 < (oend - 7));) { + HUF_DECODE_SYMBOLX2_2(op1, &bitD1); + HUF_DECODE_SYMBOLX2_2(op2, &bitD2); + HUF_DECODE_SYMBOLX2_2(op3, &bitD3); + HUF_DECODE_SYMBOLX2_2(op4, &bitD4); + HUF_DECODE_SYMBOLX2_1(op1, &bitD1); + HUF_DECODE_SYMBOLX2_1(op2, &bitD2); + HUF_DECODE_SYMBOLX2_1(op3, &bitD3); + HUF_DECODE_SYMBOLX2_1(op4, &bitD4); + HUF_DECODE_SYMBOLX2_2(op1, &bitD1); + HUF_DECODE_SYMBOLX2_2(op2, &bitD2); + HUF_DECODE_SYMBOLX2_2(op3, &bitD3); + HUF_DECODE_SYMBOLX2_2(op4, &bitD4); + HUF_DECODE_SYMBOLX2_0(op1, &bitD1); + HUF_DECODE_SYMBOLX2_0(op2, &bitD2); + HUF_DECODE_SYMBOLX2_0(op3, &bitD3); + HUF_DECODE_SYMBOLX2_0(op4, &bitD4); + endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4); + } + + /* check corruption */ + if (op1 > opStart2) + return ERROR(corruption_detected); + if (op2 > opStart3) + return ERROR(corruption_detected); + if (op3 > opStart4) + return ERROR(corruption_detected); + /* note : op4 supposed already verified within main loop */ + + /* finish bitStreams one by one */ + HUF_decodeStreamX2(op1, &bitD1, opStart2, dt, dtLog); + HUF_decodeStreamX2(op2, &bitD2, opStart3, dt, dtLog); + HUF_decodeStreamX2(op3, &bitD3, opStart4, dt, dtLog); + HUF_decodeStreamX2(op4, &bitD4, oend, dt, dtLog); + + /* check */ + endSignal = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4); + if (!endSignal) + return ERROR(corruption_detected); + + /* decoded size */ + return dstSize; + } +} + +size_t HUF_decompress4X2_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (dtd.tableType != 0) + return ERROR(GENERIC); + return HUF_decompress4X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + const BYTE *ip = (const BYTE *)cSrc; + + size_t const hSize = HUF_readDTableX2_wksp(dctx, cSrc, cSrcSize, workspace, workspaceSize); + if (HUF_isError(hSize)) + return hSize; + if (hSize >= cSrcSize) + return ERROR(srcSize_wrong); + ip += hSize; + cSrcSize -= hSize; + + return HUF_decompress4X2_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx); +} + +/* *************************/ +/* double-symbols decoding */ +/* *************************/ +typedef struct { + U16 sequence; + BYTE nbBits; + BYTE length; +} HUF_DEltX4; /* double-symbols decoding */ + +typedef struct { + BYTE symbol; + BYTE weight; +} sortedSymbol_t; + +/* HUF_fillDTableX4Level2() : + * `rankValOrigin` must be a table of at least (HUF_TABLELOG_MAX + 1) U32 */ +static void HUF_fillDTableX4Level2(HUF_DEltX4 *DTable, U32 sizeLog, const U32 consumed, const U32 *rankValOrigin, const int minWeight, + const sortedSymbol_t *sortedSymbols, const U32 sortedListSize, U32 nbBitsBaseline, U16 baseSeq) +{ + HUF_DEltX4 DElt; + U32 rankVal[HUF_TABLELOG_MAX + 1]; + + /* get pre-calculated rankVal */ + memcpy(rankVal, rankValOrigin, sizeof(rankVal)); + + /* fill skipped values */ + if (minWeight > 1) { + U32 i, skipSize = rankVal[minWeight]; + ZSTD_writeLE16(&(DElt.sequence), baseSeq); + DElt.nbBits = (BYTE)(consumed); + DElt.length = 1; + for (i = 0; i < skipSize; i++) + DTable[i] = DElt; + } + + /* fill DTable */ + { + U32 s; + for (s = 0; s < sortedListSize; s++) { /* note : sortedSymbols already skipped */ + const U32 symbol = sortedSymbols[s].symbol; + const U32 weight = sortedSymbols[s].weight; + const U32 nbBits = nbBitsBaseline - weight; + const U32 length = 1 << (sizeLog - nbBits); + const U32 start = rankVal[weight]; + U32 i = start; + const U32 end = start + length; + + ZSTD_writeLE16(&(DElt.sequence), (U16)(baseSeq + (symbol << 8))); + DElt.nbBits = (BYTE)(nbBits + consumed); + DElt.length = 2; + do { + DTable[i++] = DElt; + } while (i < end); /* since length >= 1 */ + + rankVal[weight] += length; + } + } +} + +typedef U32 rankVal_t[HUF_TABLELOG_MAX][HUF_TABLELOG_MAX + 1]; +typedef U32 rankValCol_t[HUF_TABLELOG_MAX + 1]; + +static void HUF_fillDTableX4(HUF_DEltX4 *DTable, const U32 targetLog, const sortedSymbol_t *sortedList, const U32 sortedListSize, const U32 *rankStart, + rankVal_t rankValOrigin, const U32 maxWeight, const U32 nbBitsBaseline) +{ + U32 rankVal[HUF_TABLELOG_MAX + 1]; + const int scaleLog = nbBitsBaseline - targetLog; /* note : targetLog >= srcLog, hence scaleLog <= 1 */ + const U32 minBits = nbBitsBaseline - maxWeight; + U32 s; + + memcpy(rankVal, rankValOrigin, sizeof(rankVal)); + + /* fill DTable */ + for (s = 0; s < sortedListSize; s++) { + const U16 symbol = sortedList[s].symbol; + const U32 weight = sortedList[s].weight; + const U32 nbBits = nbBitsBaseline - weight; + const U32 start = rankVal[weight]; + const U32 length = 1 << (targetLog - nbBits); + + if (targetLog - nbBits >= minBits) { /* enough room for a second symbol */ + U32 sortedRank; + int minWeight = nbBits + scaleLog; + if (minWeight < 1) + minWeight = 1; + sortedRank = rankStart[minWeight]; + HUF_fillDTableX4Level2(DTable + start, targetLog - nbBits, nbBits, rankValOrigin[nbBits], minWeight, sortedList + sortedRank, + sortedListSize - sortedRank, nbBitsBaseline, symbol); + } else { + HUF_DEltX4 DElt; + ZSTD_writeLE16(&(DElt.sequence), symbol); + DElt.nbBits = (BYTE)(nbBits); + DElt.length = 1; + { + U32 const end = start + length; + U32 u; + for (u = start; u < end; u++) + DTable[u] = DElt; + } + } + rankVal[weight] += length; + } +} + +size_t HUF_readDTableX4_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize) +{ + U32 tableLog, maxW, sizeOfSort, nbSymbols; + DTableDesc dtd = HUF_getDTableDesc(DTable); + U32 const maxTableLog = dtd.maxTableLog; + size_t iSize; + void *dtPtr = DTable + 1; /* force compiler to avoid strict-aliasing */ + HUF_DEltX4 *const dt = (HUF_DEltX4 *)dtPtr; + U32 *rankStart; + + rankValCol_t *rankVal; + U32 *rankStats; + U32 *rankStart0; + sortedSymbol_t *sortedSymbol; + BYTE *weightList; + size_t spaceUsed32 = 0; + + HUF_STATIC_ASSERT((sizeof(rankValCol_t) & 3) == 0); + + rankVal = (rankValCol_t *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += (sizeof(rankValCol_t) * HUF_TABLELOG_MAX) >> 2; + rankStats = (U32 *)workspace + spaceUsed32; + spaceUsed32 += HUF_TABLELOG_MAX + 1; + rankStart0 = (U32 *)workspace + spaceUsed32; + spaceUsed32 += HUF_TABLELOG_MAX + 2; + sortedSymbol = (sortedSymbol_t *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(sizeof(sortedSymbol_t) * (HUF_SYMBOLVALUE_MAX + 1), sizeof(U32)) >> 2; + weightList = (BYTE *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(tableLog_tooLarge); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + + rankStart = rankStart0 + 1; + memset(rankStats, 0, sizeof(U32) * (2 * HUF_TABLELOG_MAX + 2 + 1)); + + HUF_STATIC_ASSERT(sizeof(HUF_DEltX4) == sizeof(HUF_DTable)); /* if compiler fails here, assertion is wrong */ + if (maxTableLog > HUF_TABLELOG_MAX) + return ERROR(tableLog_tooLarge); + /* memset(weightList, 0, sizeof(weightList)); */ /* is not necessary, even though some analyzer complain ... */ + + iSize = HUF_readStats_wksp(weightList, HUF_SYMBOLVALUE_MAX + 1, rankStats, &nbSymbols, &tableLog, src, srcSize, workspace, workspaceSize); + if (HUF_isError(iSize)) + return iSize; + + /* check result */ + if (tableLog > maxTableLog) + return ERROR(tableLog_tooLarge); /* DTable can't fit code depth */ + + /* find maxWeight */ + for (maxW = tableLog; rankStats[maxW] == 0; maxW--) { + } /* necessarily finds a solution before 0 */ + + /* Get start index of each weight */ + { + U32 w, nextRankStart = 0; + for (w = 1; w < maxW + 1; w++) { + U32 curr = nextRankStart; + nextRankStart += rankStats[w]; + rankStart[w] = curr; + } + rankStart[0] = nextRankStart; /* put all 0w symbols at the end of sorted list*/ + sizeOfSort = nextRankStart; + } + + /* sort symbols by weight */ + { + U32 s; + for (s = 0; s < nbSymbols; s++) { + U32 const w = weightList[s]; + U32 const r = rankStart[w]++; + sortedSymbol[r].symbol = (BYTE)s; + sortedSymbol[r].weight = (BYTE)w; + } + rankStart[0] = 0; /* forget 0w symbols; this is beginning of weight(1) */ + } + + /* Build rankVal */ + { + U32 *const rankVal0 = rankVal[0]; + { + int const rescale = (maxTableLog - tableLog) - 1; /* tableLog <= maxTableLog */ + U32 nextRankVal = 0; + U32 w; + for (w = 1; w < maxW + 1; w++) { + U32 curr = nextRankVal; + nextRankVal += rankStats[w] << (w + rescale); + rankVal0[w] = curr; + } + } + { + U32 const minBits = tableLog + 1 - maxW; + U32 consumed; + for (consumed = minBits; consumed < maxTableLog - minBits + 1; consumed++) { + U32 *const rankValPtr = rankVal[consumed]; + U32 w; + for (w = 1; w < maxW + 1; w++) { + rankValPtr[w] = rankVal0[w] >> consumed; + } + } + } + } + + HUF_fillDTableX4(dt, maxTableLog, sortedSymbol, sizeOfSort, rankStart0, rankVal, maxW, tableLog + 1); + + dtd.tableLog = (BYTE)maxTableLog; + dtd.tableType = 1; + memcpy(DTable, &dtd, sizeof(dtd)); + return iSize; +} + +static U32 HUF_decodeSymbolX4(void *op, BIT_DStream_t *DStream, const HUF_DEltX4 *dt, const U32 dtLog) +{ + size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */ + memcpy(op, dt + val, 2); + BIT_skipBits(DStream, dt[val].nbBits); + return dt[val].length; +} + +static U32 HUF_decodeLastSymbolX4(void *op, BIT_DStream_t *DStream, const HUF_DEltX4 *dt, const U32 dtLog) +{ + size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */ + memcpy(op, dt + val, 1); + if (dt[val].length == 1) + BIT_skipBits(DStream, dt[val].nbBits); + else { + if (DStream->bitsConsumed < (sizeof(DStream->bitContainer) * 8)) { + BIT_skipBits(DStream, dt[val].nbBits); + if (DStream->bitsConsumed > (sizeof(DStream->bitContainer) * 8)) + /* ugly hack; works only because it's the last symbol. Note : can't easily extract nbBits from just this symbol */ + DStream->bitsConsumed = (sizeof(DStream->bitContainer) * 8); + } + } + return 1; +} + +#define HUF_DECODE_SYMBOLX4_0(ptr, DStreamPtr) ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog) + +#define HUF_DECODE_SYMBOLX4_1(ptr, DStreamPtr) \ + if (ZSTD_64bits() || (HUF_TABLELOG_MAX <= 12)) \ + ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog) + +#define HUF_DECODE_SYMBOLX4_2(ptr, DStreamPtr) \ + if (ZSTD_64bits()) \ + ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog) + +FORCE_INLINE size_t HUF_decodeStreamX4(BYTE *p, BIT_DStream_t *bitDPtr, BYTE *const pEnd, const HUF_DEltX4 *const dt, const U32 dtLog) +{ + BYTE *const pStart = p; + + /* up to 8 symbols at a time */ + while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd - (sizeof(bitDPtr->bitContainer) - 1))) { + HUF_DECODE_SYMBOLX4_2(p, bitDPtr); + HUF_DECODE_SYMBOLX4_1(p, bitDPtr); + HUF_DECODE_SYMBOLX4_2(p, bitDPtr); + HUF_DECODE_SYMBOLX4_0(p, bitDPtr); + } + + /* closer to end : up to 2 symbols at a time */ + while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p <= pEnd - 2)) + HUF_DECODE_SYMBOLX4_0(p, bitDPtr); + + while (p <= pEnd - 2) + HUF_DECODE_SYMBOLX4_0(p, bitDPtr); /* no need to reload : reached the end of DStream */ + + if (p < pEnd) + p += HUF_decodeLastSymbolX4(p, bitDPtr, dt, dtLog); + + return p - pStart; +} + +static size_t HUF_decompress1X4_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + BIT_DStream_t bitD; + + /* Init */ + { + size_t const errorCode = BIT_initDStream(&bitD, cSrc, cSrcSize); + if (HUF_isError(errorCode)) + return errorCode; + } + + /* decode */ + { + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstSize; + const void *const dtPtr = DTable + 1; /* force compiler to not use strict-aliasing */ + const HUF_DEltX4 *const dt = (const HUF_DEltX4 *)dtPtr; + DTableDesc const dtd = HUF_getDTableDesc(DTable); + HUF_decodeStreamX4(ostart, &bitD, oend, dt, dtd.tableLog); + } + + /* check */ + if (!BIT_endOfDStream(&bitD)) + return ERROR(corruption_detected); + + /* decoded size */ + return dstSize; +} + +size_t HUF_decompress1X4_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (dtd.tableType != 1) + return ERROR(GENERIC); + return HUF_decompress1X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable *DCtx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + const BYTE *ip = (const BYTE *)cSrc; + + size_t const hSize = HUF_readDTableX4_wksp(DCtx, cSrc, cSrcSize, workspace, workspaceSize); + if (HUF_isError(hSize)) + return hSize; + if (hSize >= cSrcSize) + return ERROR(srcSize_wrong); + ip += hSize; + cSrcSize -= hSize; + + return HUF_decompress1X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, DCtx); +} + +static size_t HUF_decompress4X4_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + if (cSrcSize < 10) + return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */ + + { + const BYTE *const istart = (const BYTE *)cSrc; + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstSize; + const void *const dtPtr = DTable + 1; + const HUF_DEltX4 *const dt = (const HUF_DEltX4 *)dtPtr; + + /* Init */ + BIT_DStream_t bitD1; + BIT_DStream_t bitD2; + BIT_DStream_t bitD3; + BIT_DStream_t bitD4; + size_t const length1 = ZSTD_readLE16(istart); + size_t const length2 = ZSTD_readLE16(istart + 2); + size_t const length3 = ZSTD_readLE16(istart + 4); + size_t const length4 = cSrcSize - (length1 + length2 + length3 + 6); + const BYTE *const istart1 = istart + 6; /* jumpTable */ + const BYTE *const istart2 = istart1 + length1; + const BYTE *const istart3 = istart2 + length2; + const BYTE *const istart4 = istart3 + length3; + size_t const segmentSize = (dstSize + 3) / 4; + BYTE *const opStart2 = ostart + segmentSize; + BYTE *const opStart3 = opStart2 + segmentSize; + BYTE *const opStart4 = opStart3 + segmentSize; + BYTE *op1 = ostart; + BYTE *op2 = opStart2; + BYTE *op3 = opStart3; + BYTE *op4 = opStart4; + U32 endSignal; + DTableDesc const dtd = HUF_getDTableDesc(DTable); + U32 const dtLog = dtd.tableLog; + + if (length4 > cSrcSize) + return ERROR(corruption_detected); /* overflow */ + { + size_t const errorCode = BIT_initDStream(&bitD1, istart1, length1); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD2, istart2, length2); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD3, istart3, length3); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD4, istart4, length4); + if (HUF_isError(errorCode)) + return errorCode; + } + + /* 16-32 symbols per loop (4-8 symbols per stream) */ + endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4); + for (; (endSignal == BIT_DStream_unfinished) & (op4 < (oend - (sizeof(bitD4.bitContainer) - 1)));) { + HUF_DECODE_SYMBOLX4_2(op1, &bitD1); + HUF_DECODE_SYMBOLX4_2(op2, &bitD2); + HUF_DECODE_SYMBOLX4_2(op3, &bitD3); + HUF_DECODE_SYMBOLX4_2(op4, &bitD4); + HUF_DECODE_SYMBOLX4_1(op1, &bitD1); + HUF_DECODE_SYMBOLX4_1(op2, &bitD2); + HUF_DECODE_SYMBOLX4_1(op3, &bitD3); + HUF_DECODE_SYMBOLX4_1(op4, &bitD4); + HUF_DECODE_SYMBOLX4_2(op1, &bitD1); + HUF_DECODE_SYMBOLX4_2(op2, &bitD2); + HUF_DECODE_SYMBOLX4_2(op3, &bitD3); + HUF_DECODE_SYMBOLX4_2(op4, &bitD4); + HUF_DECODE_SYMBOLX4_0(op1, &bitD1); + HUF_DECODE_SYMBOLX4_0(op2, &bitD2); + HUF_DECODE_SYMBOLX4_0(op3, &bitD3); + HUF_DECODE_SYMBOLX4_0(op4, &bitD4); + + endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4); + } + + /* check corruption */ + if (op1 > opStart2) + return ERROR(corruption_detected); + if (op2 > opStart3) + return ERROR(corruption_detected); + if (op3 > opStart4) + return ERROR(corruption_detected); + /* note : op4 already verified within main loop */ + + /* finish bitStreams one by one */ + HUF_decodeStreamX4(op1, &bitD1, opStart2, dt, dtLog); + HUF_decodeStreamX4(op2, &bitD2, opStart3, dt, dtLog); + HUF_decodeStreamX4(op3, &bitD3, opStart4, dt, dtLog); + HUF_decodeStreamX4(op4, &bitD4, oend, dt, dtLog); + + /* check */ + { + U32 const endCheck = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4); + if (!endCheck) + return ERROR(corruption_detected); + } + + /* decoded size */ + return dstSize; + } +} + +size_t HUF_decompress4X4_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (dtd.tableType != 1) + return ERROR(GENERIC); + return HUF_decompress4X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + const BYTE *ip = (const BYTE *)cSrc; + + size_t hSize = HUF_readDTableX4_wksp(dctx, cSrc, cSrcSize, workspace, workspaceSize); + if (HUF_isError(hSize)) + return hSize; + if (hSize >= cSrcSize) + return ERROR(srcSize_wrong); + ip += hSize; + cSrcSize -= hSize; + + return HUF_decompress4X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx); +} + +/* ********************************/ +/* Generic decompression selector */ +/* ********************************/ + +size_t HUF_decompress1X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc const dtd = HUF_getDTableDesc(DTable); + return dtd.tableType ? HUF_decompress1X4_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable) + : HUF_decompress1X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress4X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc const dtd = HUF_getDTableDesc(DTable); + return dtd.tableType ? HUF_decompress4X4_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable) + : HUF_decompress4X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable); +} + +typedef struct { + U32 tableTime; + U32 decode256Time; +} algo_time_t; +static const algo_time_t algoTime[16 /* Quantization */][3 /* single, double, quad */] = { + /* single, double, quad */ + {{0, 0}, {1, 1}, {2, 2}}, /* Q==0 : impossible */ + {{0, 0}, {1, 1}, {2, 2}}, /* Q==1 : impossible */ + {{38, 130}, {1313, 74}, {2151, 38}}, /* Q == 2 : 12-18% */ + {{448, 128}, {1353, 74}, {2238, 41}}, /* Q == 3 : 18-25% */ + {{556, 128}, {1353, 74}, {2238, 47}}, /* Q == 4 : 25-32% */ + {{714, 128}, {1418, 74}, {2436, 53}}, /* Q == 5 : 32-38% */ + {{883, 128}, {1437, 74}, {2464, 61}}, /* Q == 6 : 38-44% */ + {{897, 128}, {1515, 75}, {2622, 68}}, /* Q == 7 : 44-50% */ + {{926, 128}, {1613, 75}, {2730, 75}}, /* Q == 8 : 50-56% */ + {{947, 128}, {1729, 77}, {3359, 77}}, /* Q == 9 : 56-62% */ + {{1107, 128}, {2083, 81}, {4006, 84}}, /* Q ==10 : 62-69% */ + {{1177, 128}, {2379, 87}, {4785, 88}}, /* Q ==11 : 69-75% */ + {{1242, 128}, {2415, 93}, {5155, 84}}, /* Q ==12 : 75-81% */ + {{1349, 128}, {2644, 106}, {5260, 106}}, /* Q ==13 : 81-87% */ + {{1455, 128}, {2422, 124}, {4174, 124}}, /* Q ==14 : 87-93% */ + {{722, 128}, {1891, 145}, {1936, 146}}, /* Q ==15 : 93-99% */ +}; + +/** HUF_selectDecoder() : +* Tells which decoder is likely to decode faster, +* based on a set of pre-determined metrics. +* @return : 0==HUF_decompress4X2, 1==HUF_decompress4X4 . +* Assumption : 0 < cSrcSize < dstSize <= 128 KB */ +U32 HUF_selectDecoder(size_t dstSize, size_t cSrcSize) +{ + /* decoder timing evaluation */ + U32 const Q = (U32)(cSrcSize * 16 / dstSize); /* Q < 16 since dstSize > cSrcSize */ + U32 const D256 = (U32)(dstSize >> 8); + U32 const DTime0 = algoTime[Q][0].tableTime + (algoTime[Q][0].decode256Time * D256); + U32 DTime1 = algoTime[Q][1].tableTime + (algoTime[Q][1].decode256Time * D256); + DTime1 += DTime1 >> 3; /* advantage to algorithm using less memory, for cache eviction */ + + return DTime1 < DTime0; +} + +typedef size_t (*decompressionAlgo)(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize); + +size_t HUF_decompress4X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + /* validation checks */ + if (dstSize == 0) + return ERROR(dstSize_tooSmall); + if (cSrcSize > dstSize) + return ERROR(corruption_detected); /* invalid */ + if (cSrcSize == dstSize) { + memcpy(dst, cSrc, dstSize); + return dstSize; + } /* not compressed */ + if (cSrcSize == 1) { + memset(dst, *(const BYTE *)cSrc, dstSize); + return dstSize; + } /* RLE */ + + { + U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize); + return algoNb ? HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize) + : HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize); + } +} + +size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + /* validation checks */ + if (dstSize == 0) + return ERROR(dstSize_tooSmall); + if ((cSrcSize >= dstSize) || (cSrcSize <= 1)) + return ERROR(corruption_detected); /* invalid */ + + { + U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize); + return algoNb ? HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize) + : HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize); + } +} + +size_t HUF_decompress1X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + /* validation checks */ + if (dstSize == 0) + return ERROR(dstSize_tooSmall); + if (cSrcSize > dstSize) + return ERROR(corruption_detected); /* invalid */ + if (cSrcSize == dstSize) { + memcpy(dst, cSrc, dstSize); + return dstSize; + } /* not compressed */ + if (cSrcSize == 1) { + memset(dst, *(const BYTE *)cSrc, dstSize); + return dstSize; + } /* RLE */ + + { + U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize); + return algoNb ? HUF_decompress1X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize) + : HUF_decompress1X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize); + } +} |