| /* ****************************************************************** |
| Huffman encoder, part of New Generation Entropy library |
| Copyright (C) 2013-2016, Yann Collet. |
| |
| BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) |
| |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions are |
| met: |
| |
| * Redistributions of source code must retain the above copyright |
| notice, this list of conditions and the following disclaimer. |
| * Redistributions in binary form must reproduce the above |
| copyright notice, this list of conditions and the following disclaimer |
| in the documentation and/or other materials provided with the |
| distribution. |
| |
| THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| You can contact the author at : |
| - FSE+HUF source repository : https://github.com/Cyan4973/FiniteStateEntropy |
| - Public forum : https://groups.google.com/forum/#!forum/lz4c |
| ****************************************************************** */ |
| |
| /* ************************************************************** |
| * Compiler specifics |
| ****************************************************************/ |
| #ifdef _MSC_VER /* Visual Studio */ |
| # pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */ |
| #endif |
| |
| |
| /* ************************************************************** |
| * Includes |
| ****************************************************************/ |
| #include <string.h> /* memcpy, memset */ |
| #include <stdio.h> /* printf (debug) */ |
| #include "compiler.h" |
| #include "bitstream.h" |
| #include "hist.h" |
| #define FSE_STATIC_LINKING_ONLY /* FSE_optimalTableLog_internal */ |
| #include "fse.h" /* header compression */ |
| #define HUF_STATIC_LINKING_ONLY |
| #include "huf.h" |
| #include "error_private.h" |
| |
| |
| /* ************************************************************** |
| * Error Management |
| ****************************************************************/ |
| #define HUF_isError ERR_isError |
| #define HUF_STATIC_ASSERT(c) DEBUG_STATIC_ASSERT(c) /* use only *after* variable declarations */ |
| #define CHECK_V_F(e, f) size_t const e = f; if (ERR_isError(e)) return e |
| #define CHECK_F(f) { CHECK_V_F(_var_err__, f); } |
| |
| |
| /* ************************************************************** |
| * Utils |
| ****************************************************************/ |
| unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue) |
| { |
| return FSE_optimalTableLog_internal(maxTableLog, srcSize, maxSymbolValue, 1); |
| } |
| |
| |
| /* ******************************************************* |
| * HUF : Huffman block compression |
| *********************************************************/ |
| /* HUF_compressWeights() : |
| * Same as FSE_compress(), but dedicated to huff0's weights compression. |
| * The use case needs much less stack memory. |
| * Note : all elements within weightTable are supposed to be <= HUF_TABLELOG_MAX. |
| */ |
| #define MAX_FSE_TABLELOG_FOR_HUFF_HEADER 6 |
| static size_t HUF_compressWeights (void* dst, size_t dstSize, const void* weightTable, size_t wtSize) |
| { |
| BYTE* const ostart = (BYTE*) dst; |
| BYTE* op = ostart; |
| BYTE* const oend = ostart + dstSize; |
| |
| unsigned maxSymbolValue = HUF_TABLELOG_MAX; |
| U32 tableLog = MAX_FSE_TABLELOG_FOR_HUFF_HEADER; |
| |
| FSE_CTable CTable[FSE_CTABLE_SIZE_U32(MAX_FSE_TABLELOG_FOR_HUFF_HEADER, HUF_TABLELOG_MAX)]; |
| BYTE scratchBuffer[1<<MAX_FSE_TABLELOG_FOR_HUFF_HEADER]; |
| |
| unsigned count[HUF_TABLELOG_MAX+1]; |
| S16 norm[HUF_TABLELOG_MAX+1]; |
| |
| /* init conditions */ |
| if (wtSize <= 1) return 0; /* Not compressible */ |
| |
| /* Scan input and build symbol stats */ |
| { unsigned const maxCount = HIST_count_simple(count, &maxSymbolValue, weightTable, wtSize); /* never fails */ |
| if (maxCount == wtSize) return 1; /* only a single symbol in src : rle */ |
| if (maxCount == 1) return 0; /* each symbol present maximum once => not compressible */ |
| } |
| |
| tableLog = FSE_optimalTableLog(tableLog, wtSize, maxSymbolValue); |
| CHECK_F( FSE_normalizeCount(norm, tableLog, count, wtSize, maxSymbolValue) ); |
| |
| /* Write table description header */ |
| { CHECK_V_F(hSize, FSE_writeNCount(op, oend-op, norm, maxSymbolValue, tableLog) ); |
| op += hSize; |
| } |
| |
| /* Compress */ |
| CHECK_F( FSE_buildCTable_wksp(CTable, norm, maxSymbolValue, tableLog, scratchBuffer, sizeof(scratchBuffer)) ); |
| { CHECK_V_F(cSize, FSE_compress_usingCTable(op, oend - op, weightTable, wtSize, CTable) ); |
| if (cSize == 0) return 0; /* not enough space for compressed data */ |
| op += cSize; |
| } |
| |
| return op-ostart; |
| } |
| |
| |
| struct HUF_CElt_s { |
| U16 val; |
| BYTE nbBits; |
| }; /* typedef'd to HUF_CElt within "huf.h" */ |
| |
| /*! HUF_writeCTable() : |
| `CTable` : Huffman tree to save, using huf representation. |
| @return : size of saved CTable */ |
| size_t HUF_writeCTable (void* dst, size_t maxDstSize, |
| const HUF_CElt* CTable, unsigned maxSymbolValue, unsigned huffLog) |
| { |
| BYTE bitsToWeight[HUF_TABLELOG_MAX + 1]; /* precomputed conversion table */ |
| BYTE huffWeight[HUF_SYMBOLVALUE_MAX]; |
| BYTE* op = (BYTE*)dst; |
| U32 n; |
| |
| /* check conditions */ |
| if (maxSymbolValue > HUF_SYMBOLVALUE_MAX) return ERROR(maxSymbolValue_tooLarge); |
| |
| /* convert to weight */ |
| bitsToWeight[0] = 0; |
| for (n=1; n<huffLog+1; n++) |
| bitsToWeight[n] = (BYTE)(huffLog + 1 - n); |
| for (n=0; n<maxSymbolValue; n++) |
| huffWeight[n] = bitsToWeight[CTable[n].nbBits]; |
| |
| /* attempt weights compression by FSE */ |
| { CHECK_V_F(hSize, HUF_compressWeights(op+1, maxDstSize-1, huffWeight, maxSymbolValue) ); |
| if ((hSize>1) & (hSize < maxSymbolValue/2)) { /* FSE compressed */ |
| op[0] = (BYTE)hSize; |
| return hSize+1; |
| } } |
| |
| /* write raw values as 4-bits (max : 15) */ |
| if (maxSymbolValue > (256-128)) return ERROR(GENERIC); /* should not happen : likely means source cannot be compressed */ |
| if (((maxSymbolValue+1)/2) + 1 > maxDstSize) return ERROR(dstSize_tooSmall); /* not enough space within dst buffer */ |
| op[0] = (BYTE)(128 /*special case*/ + (maxSymbolValue-1)); |
| huffWeight[maxSymbolValue] = 0; /* to be sure it doesn't cause msan issue in final combination */ |
| for (n=0; n<maxSymbolValue; n+=2) |
| op[(n/2)+1] = (BYTE)((huffWeight[n] << 4) + huffWeight[n+1]); |
| return ((maxSymbolValue+1)/2) + 1; |
| } |
| |
| |
| size_t HUF_readCTable (HUF_CElt* CTable, unsigned* maxSymbolValuePtr, const void* src, size_t srcSize, unsigned* hasZeroWeights) |
| { |
| BYTE huffWeight[HUF_SYMBOLVALUE_MAX + 1]; /* init not required, even though some static analyzer may complain */ |
| U32 rankVal[HUF_TABLELOG_ABSOLUTEMAX + 1]; /* large enough for values from 0 to 16 */ |
| U32 tableLog = 0; |
| U32 nbSymbols = 0; |
| |
| /* get symbol weights */ |
| CHECK_V_F(readSize, HUF_readStats(huffWeight, HUF_SYMBOLVALUE_MAX+1, rankVal, &nbSymbols, &tableLog, src, srcSize)); |
| |
| /* check result */ |
| if (tableLog > HUF_TABLELOG_MAX) return ERROR(tableLog_tooLarge); |
| if (nbSymbols > *maxSymbolValuePtr+1) return ERROR(maxSymbolValue_tooSmall); |
| |
| /* Prepare base value per rank */ |
| { U32 n, nextRankStart = 0; |
| for (n=1; n<=tableLog; n++) { |
| U32 current = nextRankStart; |
| nextRankStart += (rankVal[n] << (n-1)); |
| rankVal[n] = current; |
| } } |
| |
| /* fill nbBits */ |
| *hasZeroWeights = 0; |
| { U32 n; for (n=0; n<nbSymbols; n++) { |
| const U32 w = huffWeight[n]; |
| *hasZeroWeights |= (w == 0); |
| CTable[n].nbBits = (BYTE)(tableLog + 1 - w) & -(w != 0); |
| } } |
| |
| /* fill val */ |
| { U16 nbPerRank[HUF_TABLELOG_MAX+2] = {0}; /* support w=0=>n=tableLog+1 */ |
| U16 valPerRank[HUF_TABLELOG_MAX+2] = {0}; |
| { U32 n; for (n=0; n<nbSymbols; n++) nbPerRank[CTable[n].nbBits]++; } |
| /* determine stating value per rank */ |
| valPerRank[tableLog+1] = 0; /* for w==0 */ |
| { U16 min = 0; |
| U32 n; for (n=tableLog; n>0; n--) { /* start at n=tablelog <-> w=1 */ |
| valPerRank[n] = min; /* get starting value within each rank */ |
| min += nbPerRank[n]; |
| min >>= 1; |
| } } |
| /* assign value within rank, symbol order */ |
| { U32 n; for (n=0; n<nbSymbols; n++) CTable[n].val = valPerRank[CTable[n].nbBits]++; } |
| } |
| |
| *maxSymbolValuePtr = nbSymbols - 1; |
| return readSize; |
| } |
| |
| U32 HUF_getNbBits(const void* symbolTable, U32 symbolValue) |
| { |
| const HUF_CElt* table = (const HUF_CElt*)symbolTable; |
| assert(symbolValue <= HUF_SYMBOLVALUE_MAX); |
| return table[symbolValue].nbBits; |
| } |
| |
| |
| typedef struct nodeElt_s { |
| U32 count; |
| U16 parent; |
| BYTE byte; |
| BYTE nbBits; |
| } nodeElt; |
| |
| static U32 HUF_setMaxHeight(nodeElt* huffNode, U32 lastNonNull, U32 maxNbBits) |
| { |
| const U32 largestBits = huffNode[lastNonNull].nbBits; |
| if (largestBits <= maxNbBits) return largestBits; /* early exit : no elt > maxNbBits */ |
| |
| /* there are several too large elements (at least >= 2) */ |
| { int totalCost = 0; |
| const U32 baseCost = 1 << (largestBits - maxNbBits); |
| U32 n = lastNonNull; |
| |
| while (huffNode[n].nbBits > maxNbBits) { |
| totalCost += baseCost - (1 << (largestBits - huffNode[n].nbBits)); |
| huffNode[n].nbBits = (BYTE)maxNbBits; |
| n --; |
| } /* n stops at huffNode[n].nbBits <= maxNbBits */ |
| while (huffNode[n].nbBits == maxNbBits) n--; /* n end at index of smallest symbol using < maxNbBits */ |
| |
| /* renorm totalCost */ |
| totalCost >>= (largestBits - maxNbBits); /* note : totalCost is necessarily a multiple of baseCost */ |
| |
| /* repay normalized cost */ |
| { U32 const noSymbol = 0xF0F0F0F0; |
| U32 rankLast[HUF_TABLELOG_MAX+2]; |
| int pos; |
| |
| /* Get pos of last (smallest) symbol per rank */ |
| memset(rankLast, 0xF0, sizeof(rankLast)); |
| { U32 currentNbBits = maxNbBits; |
| for (pos=n ; pos >= 0; pos--) { |
| if (huffNode[pos].nbBits >= currentNbBits) continue; |
| currentNbBits = huffNode[pos].nbBits; /* < maxNbBits */ |
| rankLast[maxNbBits-currentNbBits] = pos; |
| } } |
| |
| while (totalCost > 0) { |
| U32 nBitsToDecrease = BIT_highbit32(totalCost) + 1; |
| for ( ; nBitsToDecrease > 1; nBitsToDecrease--) { |
| U32 highPos = rankLast[nBitsToDecrease]; |
| U32 lowPos = rankLast[nBitsToDecrease-1]; |
| if (highPos == noSymbol) continue; |
| if (lowPos == noSymbol) break; |
| { U32 const highTotal = huffNode[highPos].count; |
| U32 const lowTotal = 2 * huffNode[lowPos].count; |
| if (highTotal <= lowTotal) break; |
| } } |
| /* only triggered when no more rank 1 symbol left => find closest one (note : there is necessarily at least one !) */ |
| /* HUF_MAX_TABLELOG test just to please gcc 5+; but it should not be necessary */ |
| while ((nBitsToDecrease<=HUF_TABLELOG_MAX) && (rankLast[nBitsToDecrease] == noSymbol)) |
| nBitsToDecrease ++; |
| totalCost -= 1 << (nBitsToDecrease-1); |
| if (rankLast[nBitsToDecrease-1] == noSymbol) |
| rankLast[nBitsToDecrease-1] = rankLast[nBitsToDecrease]; /* this rank is no longer empty */ |
| huffNode[rankLast[nBitsToDecrease]].nbBits ++; |
| if (rankLast[nBitsToDecrease] == 0) /* special case, reached largest symbol */ |
| rankLast[nBitsToDecrease] = noSymbol; |
| else { |
| rankLast[nBitsToDecrease]--; |
| if (huffNode[rankLast[nBitsToDecrease]].nbBits != maxNbBits-nBitsToDecrease) |
| rankLast[nBitsToDecrease] = noSymbol; /* this rank is now empty */ |
| } } /* while (totalCost > 0) */ |
| |
| while (totalCost < 0) { /* Sometimes, cost correction overshoot */ |
| if (rankLast[1] == noSymbol) { /* special case : no rank 1 symbol (using maxNbBits-1); let's create one from largest rank 0 (using maxNbBits) */ |
| while (huffNode[n].nbBits == maxNbBits) n--; |
| huffNode[n+1].nbBits--; |
| rankLast[1] = n+1; |
| totalCost++; |
| continue; |
| } |
| huffNode[ rankLast[1] + 1 ].nbBits--; |
| rankLast[1]++; |
| totalCost ++; |
| } } } /* there are several too large elements (at least >= 2) */ |
| |
| return maxNbBits; |
| } |
| |
| |
| typedef struct { |
| U32 base; |
| U32 current; |
| } rankPos; |
| |
| static void HUF_sort(nodeElt* huffNode, const unsigned* count, U32 maxSymbolValue) |
| { |
| rankPos rank[32]; |
| U32 n; |
| |
| memset(rank, 0, sizeof(rank)); |
| for (n=0; n<=maxSymbolValue; n++) { |
| U32 r = BIT_highbit32(count[n] + 1); |
| rank[r].base ++; |
| } |
| for (n=30; n>0; n--) rank[n-1].base += rank[n].base; |
| for (n=0; n<32; n++) rank[n].current = rank[n].base; |
| for (n=0; n<=maxSymbolValue; n++) { |
| U32 const c = count[n]; |
| U32 const r = BIT_highbit32(c+1) + 1; |
| U32 pos = rank[r].current++; |
| while ((pos > rank[r].base) && (c > huffNode[pos-1].count)) { |
| huffNode[pos] = huffNode[pos-1]; |
| pos--; |
| } |
| huffNode[pos].count = c; |
| huffNode[pos].byte = (BYTE)n; |
| } |
| } |
| |
| |
| /** HUF_buildCTable_wksp() : |
| * Same as HUF_buildCTable(), but using externally allocated scratch buffer. |
| * `workSpace` must be aligned on 4-bytes boundaries, and be at least as large as a table of HUF_CTABLE_WORKSPACE_SIZE_U32 unsigned. |
| */ |
| #define STARTNODE (HUF_SYMBOLVALUE_MAX+1) |
| typedef nodeElt huffNodeTable[HUF_CTABLE_WORKSPACE_SIZE_U32]; |
| size_t HUF_buildCTable_wksp (HUF_CElt* tree, const unsigned* count, U32 maxSymbolValue, U32 maxNbBits, void* workSpace, size_t wkspSize) |
| { |
| nodeElt* const huffNode0 = (nodeElt*)workSpace; |
| nodeElt* const huffNode = huffNode0+1; |
| U32 n, nonNullRank; |
| int lowS, lowN; |
| U16 nodeNb = STARTNODE; |
| U32 nodeRoot; |
| |
| /* safety checks */ |
| if (((size_t)workSpace & 3) != 0) return ERROR(GENERIC); /* must be aligned on 4-bytes boundaries */ |
| if (wkspSize < sizeof(huffNodeTable)) return ERROR(workSpace_tooSmall); |
| if (maxNbBits == 0) maxNbBits = HUF_TABLELOG_DEFAULT; |
| if (maxSymbolValue > HUF_SYMBOLVALUE_MAX) return ERROR(maxSymbolValue_tooLarge); |
| memset(huffNode0, 0, sizeof(huffNodeTable)); |
| |
| /* sort, decreasing order */ |
| HUF_sort(huffNode, count, maxSymbolValue); |
| |
| /* init for parents */ |
| nonNullRank = maxSymbolValue; |
| while(huffNode[nonNullRank].count == 0) nonNullRank--; |
| lowS = nonNullRank; nodeRoot = nodeNb + lowS - 1; lowN = nodeNb; |
| huffNode[nodeNb].count = huffNode[lowS].count + huffNode[lowS-1].count; |
| huffNode[lowS].parent = huffNode[lowS-1].parent = nodeNb; |
| nodeNb++; lowS-=2; |
| for (n=nodeNb; n<=nodeRoot; n++) huffNode[n].count = (U32)(1U<<30); |
| huffNode0[0].count = (U32)(1U<<31); /* fake entry, strong barrier */ |
| |
| /* create parents */ |
| while (nodeNb <= nodeRoot) { |
| U32 n1 = (huffNode[lowS].count < huffNode[lowN].count) ? lowS-- : lowN++; |
| U32 n2 = (huffNode[lowS].count < huffNode[lowN].count) ? lowS-- : lowN++; |
| huffNode[nodeNb].count = huffNode[n1].count + huffNode[n2].count; |
| huffNode[n1].parent = huffNode[n2].parent = nodeNb; |
| nodeNb++; |
| } |
| |
| /* distribute weights (unlimited tree height) */ |
| huffNode[nodeRoot].nbBits = 0; |
| for (n=nodeRoot-1; n>=STARTNODE; n--) |
| huffNode[n].nbBits = huffNode[ huffNode[n].parent ].nbBits + 1; |
| for (n=0; n<=nonNullRank; n++) |
| huffNode[n].nbBits = huffNode[ huffNode[n].parent ].nbBits + 1; |
| |
| /* enforce maxTableLog */ |
| maxNbBits = HUF_setMaxHeight(huffNode, nonNullRank, maxNbBits); |
| |
| /* fill result into tree (val, nbBits) */ |
| { U16 nbPerRank[HUF_TABLELOG_MAX+1] = {0}; |
| U16 valPerRank[HUF_TABLELOG_MAX+1] = {0}; |
| if (maxNbBits > HUF_TABLELOG_MAX) return ERROR(GENERIC); /* check fit into table */ |
| for (n=0; n<=nonNullRank; n++) |
| nbPerRank[huffNode[n].nbBits]++; |
| /* determine stating value per rank */ |
| { U16 min = 0; |
| for (n=maxNbBits; n>0; n--) { |
| valPerRank[n] = min; /* get starting value within each rank */ |
| min += nbPerRank[n]; |
| min >>= 1; |
| } } |
| for (n=0; n<=maxSymbolValue; n++) |
| tree[huffNode[n].byte].nbBits = huffNode[n].nbBits; /* push nbBits per symbol, symbol order */ |
| for (n=0; n<=maxSymbolValue; n++) |
| tree[n].val = valPerRank[tree[n].nbBits]++; /* assign value within rank, symbol order */ |
| } |
| |
| return maxNbBits; |
| } |
| |
| /** HUF_buildCTable() : |
| * @return : maxNbBits |
| * Note : count is used before tree is written, so they can safely overlap |
| */ |
| size_t HUF_buildCTable (HUF_CElt* tree, const unsigned* count, unsigned maxSymbolValue, unsigned maxNbBits) |
| { |
| huffNodeTable nodeTable; |
| return HUF_buildCTable_wksp(tree, count, maxSymbolValue, maxNbBits, nodeTable, sizeof(nodeTable)); |
| } |
| |
| size_t HUF_estimateCompressedSize(const HUF_CElt* CTable, const unsigned* count, unsigned maxSymbolValue) |
| { |
| size_t nbBits = 0; |
| int s; |
| for (s = 0; s <= (int)maxSymbolValue; ++s) { |
| nbBits += CTable[s].nbBits * count[s]; |
| } |
| return nbBits >> 3; |
| } |
| |
| static int HUF_validateCTable(const HUF_CElt* CTable, const unsigned* count, unsigned maxSymbolValue) { |
| int bad = 0; |
| int s; |
| for (s = 0; s <= (int)maxSymbolValue; ++s) { |
| bad |= (count[s] != 0) & (CTable[s].nbBits == 0); |
| } |
| return !bad; |
| } |
| |
| size_t HUF_compressBound(size_t size) { return HUF_COMPRESSBOUND(size); } |
| |
| FORCE_INLINE_TEMPLATE void |
| HUF_encodeSymbol(BIT_CStream_t* bitCPtr, U32 symbol, const HUF_CElt* CTable) |
| { |
| BIT_addBitsFast(bitCPtr, CTable[symbol].val, CTable[symbol].nbBits); |
| } |
| |
| #define HUF_FLUSHBITS(s) BIT_flushBits(s) |
| |
| #define HUF_FLUSHBITS_1(stream) \ |
| if (sizeof((stream)->bitContainer)*8 < HUF_TABLELOG_MAX*2+7) HUF_FLUSHBITS(stream) |
| |
| #define HUF_FLUSHBITS_2(stream) \ |
| if (sizeof((stream)->bitContainer)*8 < HUF_TABLELOG_MAX*4+7) HUF_FLUSHBITS(stream) |
| |
| FORCE_INLINE_TEMPLATE size_t |
| HUF_compress1X_usingCTable_internal_body(void* dst, size_t dstSize, |
| const void* src, size_t srcSize, |
| const HUF_CElt* CTable) |
| { |
| const BYTE* ip = (const BYTE*) src; |
| BYTE* const ostart = (BYTE*)dst; |
| BYTE* const oend = ostart + dstSize; |
| BYTE* op = ostart; |
| size_t n; |
| BIT_CStream_t bitC; |
| |
| /* init */ |
| if (dstSize < 8) return 0; /* not enough space to compress */ |
| { size_t const initErr = BIT_initCStream(&bitC, op, oend-op); |
| if (HUF_isError(initErr)) return 0; } |
| |
| n = srcSize & ~3; /* join to mod 4 */ |
| switch (srcSize & 3) |
| { |
| case 3 : HUF_encodeSymbol(&bitC, ip[n+ 2], CTable); |
| HUF_FLUSHBITS_2(&bitC); |
| /* fall-through */ |
| case 2 : HUF_encodeSymbol(&bitC, ip[n+ 1], CTable); |
| HUF_FLUSHBITS_1(&bitC); |
| /* fall-through */ |
| case 1 : HUF_encodeSymbol(&bitC, ip[n+ 0], CTable); |
| HUF_FLUSHBITS(&bitC); |
| /* fall-through */ |
| case 0 : /* fall-through */ |
| default: break; |
| } |
| |
| for (; n>0; n-=4) { /* note : n&3==0 at this stage */ |
| HUF_encodeSymbol(&bitC, ip[n- 1], CTable); |
| HUF_FLUSHBITS_1(&bitC); |
| HUF_encodeSymbol(&bitC, ip[n- 2], CTable); |
| HUF_FLUSHBITS_2(&bitC); |
| HUF_encodeSymbol(&bitC, ip[n- 3], CTable); |
| HUF_FLUSHBITS_1(&bitC); |
| HUF_encodeSymbol(&bitC, ip[n- 4], CTable); |
| HUF_FLUSHBITS(&bitC); |
| } |
| |
| return BIT_closeCStream(&bitC); |
| } |
| |
| #if DYNAMIC_BMI2 |
| |
| static TARGET_ATTRIBUTE("bmi2") size_t |
| HUF_compress1X_usingCTable_internal_bmi2(void* dst, size_t dstSize, |
| const void* src, size_t srcSize, |
| const HUF_CElt* CTable) |
| { |
| return HUF_compress1X_usingCTable_internal_body(dst, dstSize, src, srcSize, CTable); |
| } |
| |
| static size_t |
| HUF_compress1X_usingCTable_internal_default(void* dst, size_t dstSize, |
| const void* src, size_t srcSize, |
| const HUF_CElt* CTable) |
| { |
| return HUF_compress1X_usingCTable_internal_body(dst, dstSize, src, srcSize, CTable); |
| } |
| |
| static size_t |
| HUF_compress1X_usingCTable_internal(void* dst, size_t dstSize, |
| const void* src, size_t srcSize, |
| const HUF_CElt* CTable, const int bmi2) |
| { |
| if (bmi2) { |
| return HUF_compress1X_usingCTable_internal_bmi2(dst, dstSize, src, srcSize, CTable); |
| } |
| return HUF_compress1X_usingCTable_internal_default(dst, dstSize, src, srcSize, CTable); |
| } |
| |
| #else |
| |
| static size_t |
| HUF_compress1X_usingCTable_internal(void* dst, size_t dstSize, |
| const void* src, size_t srcSize, |
| const HUF_CElt* CTable, const int bmi2) |
| { |
| (void)bmi2; |
| return HUF_compress1X_usingCTable_internal_body(dst, dstSize, src, srcSize, CTable); |
| } |
| |
| #endif |
| |
| size_t HUF_compress1X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable) |
| { |
| return HUF_compress1X_usingCTable_internal(dst, dstSize, src, srcSize, CTable, /* bmi2 */ 0); |
| } |
| |
| |
| static size_t |
| HUF_compress4X_usingCTable_internal(void* dst, size_t dstSize, |
| const void* src, size_t srcSize, |
| const HUF_CElt* CTable, int bmi2) |
| { |
| size_t const segmentSize = (srcSize+3)/4; /* first 3 segments */ |
| const BYTE* ip = (const BYTE*) src; |
| const BYTE* const iend = ip + srcSize; |
| BYTE* const ostart = (BYTE*) dst; |
| BYTE* const oend = ostart + dstSize; |
| BYTE* op = ostart; |
| |
| if (dstSize < 6 + 1 + 1 + 1 + 8) return 0; /* minimum space to compress successfully */ |
| if (srcSize < 12) return 0; /* no saving possible : too small input */ |
| op += 6; /* jumpTable */ |
| |
| { CHECK_V_F(cSize, HUF_compress1X_usingCTable_internal(op, oend-op, ip, segmentSize, CTable, bmi2) ); |
| if (cSize==0) return 0; |
| assert(cSize <= 65535); |
| MEM_writeLE16(ostart, (U16)cSize); |
| op += cSize; |
| } |
| |
| ip += segmentSize; |
| { CHECK_V_F(cSize, HUF_compress1X_usingCTable_internal(op, oend-op, ip, segmentSize, CTable, bmi2) ); |
| if (cSize==0) return 0; |
| assert(cSize <= 65535); |
| MEM_writeLE16(ostart+2, (U16)cSize); |
| op += cSize; |
| } |
| |
| ip += segmentSize; |
| { CHECK_V_F(cSize, HUF_compress1X_usingCTable_internal(op, oend-op, ip, segmentSize, CTable, bmi2) ); |
| if (cSize==0) return 0; |
| assert(cSize <= 65535); |
| MEM_writeLE16(ostart+4, (U16)cSize); |
| op += cSize; |
| } |
| |
| ip += segmentSize; |
| { CHECK_V_F(cSize, HUF_compress1X_usingCTable_internal(op, oend-op, ip, iend-ip, CTable, bmi2) ); |
| if (cSize==0) return 0; |
| op += cSize; |
| } |
| |
| return op-ostart; |
| } |
| |
| size_t HUF_compress4X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable) |
| { |
| return HUF_compress4X_usingCTable_internal(dst, dstSize, src, srcSize, CTable, /* bmi2 */ 0); |
| } |
| |
| typedef enum { HUF_singleStream, HUF_fourStreams } HUF_nbStreams_e; |
| |
| static size_t HUF_compressCTable_internal( |
| BYTE* const ostart, BYTE* op, BYTE* const oend, |
| const void* src, size_t srcSize, |
| HUF_nbStreams_e nbStreams, const HUF_CElt* CTable, const int bmi2) |
| { |
| size_t const cSize = (nbStreams==HUF_singleStream) ? |
| HUF_compress1X_usingCTable_internal(op, oend - op, src, srcSize, CTable, bmi2) : |
| HUF_compress4X_usingCTable_internal(op, oend - op, src, srcSize, CTable, bmi2); |
| if (HUF_isError(cSize)) { return cSize; } |
| if (cSize==0) { return 0; } /* uncompressible */ |
| op += cSize; |
| /* check compressibility */ |
| if ((size_t)(op-ostart) >= srcSize-1) { return 0; } |
| return op-ostart; |
| } |
| |
| typedef struct { |
| unsigned count[HUF_SYMBOLVALUE_MAX + 1]; |
| HUF_CElt CTable[HUF_SYMBOLVALUE_MAX + 1]; |
| huffNodeTable nodeTable; |
| } HUF_compress_tables_t; |
| |
| /* HUF_compress_internal() : |
| * `workSpace` must a table of at least HUF_WORKSPACE_SIZE_U32 unsigned */ |
| static size_t |
| HUF_compress_internal (void* dst, size_t dstSize, |
| const void* src, size_t srcSize, |
| unsigned maxSymbolValue, unsigned huffLog, |
| HUF_nbStreams_e nbStreams, |
| void* workSpace, size_t wkspSize, |
| HUF_CElt* oldHufTable, HUF_repeat* repeat, int preferRepeat, |
| const int bmi2) |
| { |
| HUF_compress_tables_t* const table = (HUF_compress_tables_t*)workSpace; |
| BYTE* const ostart = (BYTE*)dst; |
| BYTE* const oend = ostart + dstSize; |
| BYTE* op = ostart; |
| |
| /* checks & inits */ |
| if (((size_t)workSpace & 3) != 0) return ERROR(GENERIC); /* must be aligned on 4-bytes boundaries */ |
| if (wkspSize < HUF_WORKSPACE_SIZE) return ERROR(workSpace_tooSmall); |
| if (!srcSize) return 0; /* Uncompressed */ |
| if (!dstSize) return 0; /* cannot fit anything within dst budget */ |
| if (srcSize > HUF_BLOCKSIZE_MAX) return ERROR(srcSize_wrong); /* current block size limit */ |
| if (huffLog > HUF_TABLELOG_MAX) return ERROR(tableLog_tooLarge); |
| if (maxSymbolValue > HUF_SYMBOLVALUE_MAX) return ERROR(maxSymbolValue_tooLarge); |
| if (!maxSymbolValue) maxSymbolValue = HUF_SYMBOLVALUE_MAX; |
| if (!huffLog) huffLog = HUF_TABLELOG_DEFAULT; |
| |
| /* Heuristic : If old table is valid, use it for small inputs */ |
| if (preferRepeat && repeat && *repeat == HUF_repeat_valid) { |
| return HUF_compressCTable_internal(ostart, op, oend, |
| src, srcSize, |
| nbStreams, oldHufTable, bmi2); |
| } |
| |
| /* Scan input and build symbol stats */ |
| { CHECK_V_F(largest, HIST_count_wksp (table->count, &maxSymbolValue, (const BYTE*)src, srcSize, workSpace, wkspSize) ); |
| if (largest == srcSize) { *ostart = ((const BYTE*)src)[0]; return 1; } /* single symbol, rle */ |
| if (largest <= (srcSize >> 7)+4) return 0; /* heuristic : probably not compressible enough */ |
| } |
| |
| /* Check validity of previous table */ |
| if ( repeat |
| && *repeat == HUF_repeat_check |
| && !HUF_validateCTable(oldHufTable, table->count, maxSymbolValue)) { |
| *repeat = HUF_repeat_none; |
| } |
| /* Heuristic : use existing table for small inputs */ |
| if (preferRepeat && repeat && *repeat != HUF_repeat_none) { |
| return HUF_compressCTable_internal(ostart, op, oend, |
| src, srcSize, |
| nbStreams, oldHufTable, bmi2); |
| } |
| |
| /* Build Huffman Tree */ |
| huffLog = HUF_optimalTableLog(huffLog, srcSize, maxSymbolValue); |
| { size_t const maxBits = HUF_buildCTable_wksp(table->CTable, table->count, |
| maxSymbolValue, huffLog, |
| table->nodeTable, sizeof(table->nodeTable)); |
| CHECK_F(maxBits); |
| huffLog = (U32)maxBits; |
| /* Zero unused symbols in CTable, so we can check it for validity */ |
| memset(table->CTable + (maxSymbolValue + 1), 0, |
| sizeof(table->CTable) - ((maxSymbolValue + 1) * sizeof(HUF_CElt))); |
| } |
| |
| /* Write table description header */ |
| { CHECK_V_F(hSize, HUF_writeCTable (op, dstSize, table->CTable, maxSymbolValue, huffLog) ); |
| /* Check if using previous huffman table is beneficial */ |
| if (repeat && *repeat != HUF_repeat_none) { |
| size_t const oldSize = HUF_estimateCompressedSize(oldHufTable, table->count, maxSymbolValue); |
| size_t const newSize = HUF_estimateCompressedSize(table->CTable, table->count, maxSymbolValue); |
| if (oldSize <= hSize + newSize || hSize + 12 >= srcSize) { |
| return HUF_compressCTable_internal(ostart, op, oend, |
| src, srcSize, |
| nbStreams, oldHufTable, bmi2); |
| } } |
| |
| /* Use the new huffman table */ |
| if (hSize + 12ul >= srcSize) { return 0; } |
| op += hSize; |
| if (repeat) { *repeat = HUF_repeat_none; } |
| if (oldHufTable) |
| memcpy(oldHufTable, table->CTable, sizeof(table->CTable)); /* Save new table */ |
| } |
| return HUF_compressCTable_internal(ostart, op, oend, |
| src, srcSize, |
| nbStreams, table->CTable, bmi2); |
| } |
| |
| |
| size_t HUF_compress1X_wksp (void* dst, size_t dstSize, |
| const void* src, size_t srcSize, |
| unsigned maxSymbolValue, unsigned huffLog, |
| void* workSpace, size_t wkspSize) |
| { |
| return HUF_compress_internal(dst, dstSize, src, srcSize, |
| maxSymbolValue, huffLog, HUF_singleStream, |
| workSpace, wkspSize, |
| NULL, NULL, 0, 0 /*bmi2*/); |
| } |
| |
| size_t HUF_compress1X_repeat (void* dst, size_t dstSize, |
| const void* src, size_t srcSize, |
| unsigned maxSymbolValue, unsigned huffLog, |
| void* workSpace, size_t wkspSize, |
| HUF_CElt* hufTable, HUF_repeat* repeat, int preferRepeat, int bmi2) |
| { |
| return HUF_compress_internal(dst, dstSize, src, srcSize, |
| maxSymbolValue, huffLog, HUF_singleStream, |
| workSpace, wkspSize, hufTable, |
| repeat, preferRepeat, bmi2); |
| } |
| |
| size_t HUF_compress1X (void* dst, size_t dstSize, |
| const void* src, size_t srcSize, |
| unsigned maxSymbolValue, unsigned huffLog) |
| { |
| unsigned workSpace[HUF_WORKSPACE_SIZE_U32]; |
| return HUF_compress1X_wksp(dst, dstSize, src, srcSize, maxSymbolValue, huffLog, workSpace, sizeof(workSpace)); |
| } |
| |
| /* HUF_compress4X_repeat(): |
| * compress input using 4 streams. |
| * provide workspace to generate compression tables */ |
| size_t HUF_compress4X_wksp (void* dst, size_t dstSize, |
| const void* src, size_t srcSize, |
| unsigned maxSymbolValue, unsigned huffLog, |
| void* workSpace, size_t wkspSize) |
| { |
| return HUF_compress_internal(dst, dstSize, src, srcSize, |
| maxSymbolValue, huffLog, HUF_fourStreams, |
| workSpace, wkspSize, |
| NULL, NULL, 0, 0 /*bmi2*/); |
| } |
| |
| /* HUF_compress4X_repeat(): |
| * compress input using 4 streams. |
| * re-use an existing huffman compression table */ |
| size_t HUF_compress4X_repeat (void* dst, size_t dstSize, |
| const void* src, size_t srcSize, |
| unsigned maxSymbolValue, unsigned huffLog, |
| void* workSpace, size_t wkspSize, |
| HUF_CElt* hufTable, HUF_repeat* repeat, int preferRepeat, int bmi2) |
| { |
| return HUF_compress_internal(dst, dstSize, src, srcSize, |
| maxSymbolValue, huffLog, HUF_fourStreams, |
| workSpace, wkspSize, |
| hufTable, repeat, preferRepeat, bmi2); |
| } |
| |
| size_t HUF_compress2 (void* dst, size_t dstSize, |
| const void* src, size_t srcSize, |
| unsigned maxSymbolValue, unsigned huffLog) |
| { |
| unsigned workSpace[HUF_WORKSPACE_SIZE_U32]; |
| return HUF_compress4X_wksp(dst, dstSize, src, srcSize, maxSymbolValue, huffLog, workSpace, sizeof(workSpace)); |
| } |
| |
| size_t HUF_compress (void* dst, size_t maxDstSize, const void* src, size_t srcSize) |
| { |
| return HUF_compress2(dst, maxDstSize, src, srcSize, 255, HUF_TABLELOG_DEFAULT); |
| } |