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diff --git a/vendor/github.com/DataDog/zstd/huf_compress.c b/vendor/github.com/DataDog/zstd/huf_compress.c
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+++ b/vendor/github.com/DataDog/zstd/huf_compress.c
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+/* ******************************************************************
+ 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)
+{
+ 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 */
+ { U32 n; for (n=0; n<nbSymbols; n++) {
+ const U32 w = huffWeight[n];
+ CTable[n].nbBits = (BYTE)(tableLog + 1 - w);
+ } }
+
+ /* 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));
+}
+
+static size_t HUF_estimateCompressedSize(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);
+}