lib: add Zstandard decompression support
Add the zstd library from Linux kernel (only decompression support).
There are minimal changes to build with U-Boot, otherwise the files are
identical to Linux commit dc35da16 from March 2018, the files had not
been touched since in kernel. Also SPDX lincese tags were added.
Signed-off-by: Marek Behún <marek.behun@nic.cz>
diff --git a/lib/zstd/huf_decompress.c b/lib/zstd/huf_decompress.c
new file mode 100644
index 0000000..97145b0
--- /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);
+ }
+}