v4.19.13 snapshot.
diff --git a/lib/zstd/fse_compress.c b/lib/zstd/fse_compress.c
new file mode 100644
index 0000000..ef3d174
--- /dev/null
+++ b/lib/zstd/fse_compress.c
@@ -0,0 +1,795 @@
+/*
+ * FSE : Finite State Entropy encoder
+ * Copyright (C) 2013-2015, 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.
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation. This program is dual-licensed; you may select
+ * either version 2 of the GNU General Public License ("GPL") or BSD license
+ * ("BSD").
+ *
+ * You can contact the author at :
+ * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
+ */
+
+/* **************************************************************
+* Compiler specifics
+****************************************************************/
+#define FORCE_INLINE static __always_inline
+
+/* **************************************************************
+* Includes
+****************************************************************/
+#include "bitstream.h"
+#include "fse.h"
+#include <linux/compiler.h>
+#include <linux/kernel.h>
+#include <linux/math64.h>
+#include <linux/string.h> /* memcpy, memset */
+
+/* **************************************************************
+* Error Management
+****************************************************************/
+#define FSE_STATIC_ASSERT(c) \
+ { \
+ enum { FSE_static_assert = 1 / (int)(!!(c)) }; \
+ } /* use only *after* variable declarations */
+
+/* **************************************************************
+* Templates
+****************************************************************/
+/*
+ designed to be included
+ for type-specific functions (template emulation in C)
+ Objective is to write these functions only once, for improved maintenance
+*/
+
+/* safety checks */
+#ifndef FSE_FUNCTION_EXTENSION
+#error "FSE_FUNCTION_EXTENSION must be defined"
+#endif
+#ifndef FSE_FUNCTION_TYPE
+#error "FSE_FUNCTION_TYPE must be defined"
+#endif
+
+/* Function names */
+#define FSE_CAT(X, Y) X##Y
+#define FSE_FUNCTION_NAME(X, Y) FSE_CAT(X, Y)
+#define FSE_TYPE_NAME(X, Y) FSE_CAT(X, Y)
+
+/* Function templates */
+
+/* FSE_buildCTable_wksp() :
+ * Same as FSE_buildCTable(), but using an externally allocated scratch buffer (`workSpace`).
+ * wkspSize should be sized to handle worst case situation, which is `1<<max_tableLog * sizeof(FSE_FUNCTION_TYPE)`
+ * workSpace must also be properly aligned with FSE_FUNCTION_TYPE requirements
+ */
+size_t FSE_buildCTable_wksp(FSE_CTable *ct, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workspace, size_t workspaceSize)
+{
+ U32 const tableSize = 1 << tableLog;
+ U32 const tableMask = tableSize - 1;
+ void *const ptr = ct;
+ U16 *const tableU16 = ((U16 *)ptr) + 2;
+ void *const FSCT = ((U32 *)ptr) + 1 /* header */ + (tableLog ? tableSize >> 1 : 1);
+ FSE_symbolCompressionTransform *const symbolTT = (FSE_symbolCompressionTransform *)(FSCT);
+ U32 const step = FSE_TABLESTEP(tableSize);
+ U32 highThreshold = tableSize - 1;
+
+ U32 *cumul;
+ FSE_FUNCTION_TYPE *tableSymbol;
+ size_t spaceUsed32 = 0;
+
+ cumul = (U32 *)workspace + spaceUsed32;
+ spaceUsed32 += FSE_MAX_SYMBOL_VALUE + 2;
+ tableSymbol = (FSE_FUNCTION_TYPE *)((U32 *)workspace + spaceUsed32);
+ spaceUsed32 += ALIGN(sizeof(FSE_FUNCTION_TYPE) * ((size_t)1 << tableLog), sizeof(U32)) >> 2;
+
+ if ((spaceUsed32 << 2) > workspaceSize)
+ return ERROR(tableLog_tooLarge);
+ workspace = (U32 *)workspace + spaceUsed32;
+ workspaceSize -= (spaceUsed32 << 2);
+
+ /* CTable header */
+ tableU16[-2] = (U16)tableLog;
+ tableU16[-1] = (U16)maxSymbolValue;
+
+ /* For explanations on how to distribute symbol values over the table :
+ * http://fastcompression.blogspot.fr/2014/02/fse-distributing-symbol-values.html */
+
+ /* symbol start positions */
+ {
+ U32 u;
+ cumul[0] = 0;
+ for (u = 1; u <= maxSymbolValue + 1; u++) {
+ if (normalizedCounter[u - 1] == -1) { /* Low proba symbol */
+ cumul[u] = cumul[u - 1] + 1;
+ tableSymbol[highThreshold--] = (FSE_FUNCTION_TYPE)(u - 1);
+ } else {
+ cumul[u] = cumul[u - 1] + normalizedCounter[u - 1];
+ }
+ }
+ cumul[maxSymbolValue + 1] = tableSize + 1;
+ }
+
+ /* Spread symbols */
+ {
+ U32 position = 0;
+ U32 symbol;
+ for (symbol = 0; symbol <= maxSymbolValue; symbol++) {
+ int nbOccurences;
+ for (nbOccurences = 0; nbOccurences < normalizedCounter[symbol]; nbOccurences++) {
+ tableSymbol[position] = (FSE_FUNCTION_TYPE)symbol;
+ position = (position + step) & tableMask;
+ while (position > highThreshold)
+ position = (position + step) & tableMask; /* Low proba area */
+ }
+ }
+
+ if (position != 0)
+ return ERROR(GENERIC); /* Must have gone through all positions */
+ }
+
+ /* Build table */
+ {
+ U32 u;
+ for (u = 0; u < tableSize; u++) {
+ FSE_FUNCTION_TYPE s = tableSymbol[u]; /* note : static analyzer may not understand tableSymbol is properly initialized */
+ tableU16[cumul[s]++] = (U16)(tableSize + u); /* TableU16 : sorted by symbol order; gives next state value */
+ }
+ }
+
+ /* Build Symbol Transformation Table */
+ {
+ unsigned total = 0;
+ unsigned s;
+ for (s = 0; s <= maxSymbolValue; s++) {
+ switch (normalizedCounter[s]) {
+ case 0: break;
+
+ case -1:
+ case 1:
+ symbolTT[s].deltaNbBits = (tableLog << 16) - (1 << tableLog);
+ symbolTT[s].deltaFindState = total - 1;
+ total++;
+ break;
+ default: {
+ U32 const maxBitsOut = tableLog - BIT_highbit32(normalizedCounter[s] - 1);
+ U32 const minStatePlus = normalizedCounter[s] << maxBitsOut;
+ symbolTT[s].deltaNbBits = (maxBitsOut << 16) - minStatePlus;
+ symbolTT[s].deltaFindState = total - normalizedCounter[s];
+ total += normalizedCounter[s];
+ }
+ }
+ }
+ }
+
+ return 0;
+}
+
+/*-**************************************************************
+* FSE NCount encoding-decoding
+****************************************************************/
+size_t FSE_NCountWriteBound(unsigned maxSymbolValue, unsigned tableLog)
+{
+ size_t const maxHeaderSize = (((maxSymbolValue + 1) * tableLog) >> 3) + 3;
+ return maxSymbolValue ? maxHeaderSize : FSE_NCOUNTBOUND; /* maxSymbolValue==0 ? use default */
+}
+
+static size_t FSE_writeNCount_generic(void *header, size_t headerBufferSize, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog,
+ unsigned writeIsSafe)
+{
+ BYTE *const ostart = (BYTE *)header;
+ BYTE *out = ostart;
+ BYTE *const oend = ostart + headerBufferSize;
+ int nbBits;
+ const int tableSize = 1 << tableLog;
+ int remaining;
+ int threshold;
+ U32 bitStream;
+ int bitCount;
+ unsigned charnum = 0;
+ int previous0 = 0;
+
+ bitStream = 0;
+ bitCount = 0;
+ /* Table Size */
+ bitStream += (tableLog - FSE_MIN_TABLELOG) << bitCount;
+ bitCount += 4;
+
+ /* Init */
+ remaining = tableSize + 1; /* +1 for extra accuracy */
+ threshold = tableSize;
+ nbBits = tableLog + 1;
+
+ while (remaining > 1) { /* stops at 1 */
+ if (previous0) {
+ unsigned start = charnum;
+ while (!normalizedCounter[charnum])
+ charnum++;
+ while (charnum >= start + 24) {
+ start += 24;
+ bitStream += 0xFFFFU << bitCount;
+ if ((!writeIsSafe) && (out > oend - 2))
+ return ERROR(dstSize_tooSmall); /* Buffer overflow */
+ out[0] = (BYTE)bitStream;
+ out[1] = (BYTE)(bitStream >> 8);
+ out += 2;
+ bitStream >>= 16;
+ }
+ while (charnum >= start + 3) {
+ start += 3;
+ bitStream += 3 << bitCount;
+ bitCount += 2;
+ }
+ bitStream += (charnum - start) << bitCount;
+ bitCount += 2;
+ if (bitCount > 16) {
+ if ((!writeIsSafe) && (out > oend - 2))
+ return ERROR(dstSize_tooSmall); /* Buffer overflow */
+ out[0] = (BYTE)bitStream;
+ out[1] = (BYTE)(bitStream >> 8);
+ out += 2;
+ bitStream >>= 16;
+ bitCount -= 16;
+ }
+ }
+ {
+ int count = normalizedCounter[charnum++];
+ int const max = (2 * threshold - 1) - remaining;
+ remaining -= count < 0 ? -count : count;
+ count++; /* +1 for extra accuracy */
+ if (count >= threshold)
+ count += max; /* [0..max[ [max..threshold[ (...) [threshold+max 2*threshold[ */
+ bitStream += count << bitCount;
+ bitCount += nbBits;
+ bitCount -= (count < max);
+ previous0 = (count == 1);
+ if (remaining < 1)
+ return ERROR(GENERIC);
+ while (remaining < threshold)
+ nbBits--, threshold >>= 1;
+ }
+ if (bitCount > 16) {
+ if ((!writeIsSafe) && (out > oend - 2))
+ return ERROR(dstSize_tooSmall); /* Buffer overflow */
+ out[0] = (BYTE)bitStream;
+ out[1] = (BYTE)(bitStream >> 8);
+ out += 2;
+ bitStream >>= 16;
+ bitCount -= 16;
+ }
+ }
+
+ /* flush remaining bitStream */
+ if ((!writeIsSafe) && (out > oend - 2))
+ return ERROR(dstSize_tooSmall); /* Buffer overflow */
+ out[0] = (BYTE)bitStream;
+ out[1] = (BYTE)(bitStream >> 8);
+ out += (bitCount + 7) / 8;
+
+ if (charnum > maxSymbolValue + 1)
+ return ERROR(GENERIC);
+
+ return (out - ostart);
+}
+
+size_t FSE_writeNCount(void *buffer, size_t bufferSize, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog)
+{
+ if (tableLog > FSE_MAX_TABLELOG)
+ return ERROR(tableLog_tooLarge); /* Unsupported */
+ if (tableLog < FSE_MIN_TABLELOG)
+ return ERROR(GENERIC); /* Unsupported */
+
+ if (bufferSize < FSE_NCountWriteBound(maxSymbolValue, tableLog))
+ return FSE_writeNCount_generic(buffer, bufferSize, normalizedCounter, maxSymbolValue, tableLog, 0);
+
+ return FSE_writeNCount_generic(buffer, bufferSize, normalizedCounter, maxSymbolValue, tableLog, 1);
+}
+
+/*-**************************************************************
+* Counting histogram
+****************************************************************/
+/*! FSE_count_simple
+ This function counts byte values within `src`, and store the histogram into table `count`.
+ It doesn't use any additional memory.
+ But this function is unsafe : it doesn't check that all values within `src` can fit into `count`.
+ For this reason, prefer using a table `count` with 256 elements.
+ @return : count of most numerous element
+*/
+size_t FSE_count_simple(unsigned *count, unsigned *maxSymbolValuePtr, const void *src, size_t srcSize)
+{
+ const BYTE *ip = (const BYTE *)src;
+ const BYTE *const end = ip + srcSize;
+ unsigned maxSymbolValue = *maxSymbolValuePtr;
+ unsigned max = 0;
+
+ memset(count, 0, (maxSymbolValue + 1) * sizeof(*count));
+ if (srcSize == 0) {
+ *maxSymbolValuePtr = 0;
+ return 0;
+ }
+
+ while (ip < end)
+ count[*ip++]++;
+
+ while (!count[maxSymbolValue])
+ maxSymbolValue--;
+ *maxSymbolValuePtr = maxSymbolValue;
+
+ {
+ U32 s;
+ for (s = 0; s <= maxSymbolValue; s++)
+ if (count[s] > max)
+ max = count[s];
+ }
+
+ return (size_t)max;
+}
+
+/* FSE_count_parallel_wksp() :
+ * Same as FSE_count_parallel(), but using an externally provided scratch buffer.
+ * `workSpace` size must be a minimum of `1024 * sizeof(unsigned)`` */
+static size_t FSE_count_parallel_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *source, size_t sourceSize, unsigned checkMax,
+ unsigned *const workSpace)
+{
+ const BYTE *ip = (const BYTE *)source;
+ const BYTE *const iend = ip + sourceSize;
+ unsigned maxSymbolValue = *maxSymbolValuePtr;
+ unsigned max = 0;
+ U32 *const Counting1 = workSpace;
+ U32 *const Counting2 = Counting1 + 256;
+ U32 *const Counting3 = Counting2 + 256;
+ U32 *const Counting4 = Counting3 + 256;
+
+ memset(Counting1, 0, 4 * 256 * sizeof(unsigned));
+
+ /* safety checks */
+ if (!sourceSize) {
+ memset(count, 0, maxSymbolValue + 1);
+ *maxSymbolValuePtr = 0;
+ return 0;
+ }
+ if (!maxSymbolValue)
+ maxSymbolValue = 255; /* 0 == default */
+
+ /* by stripes of 16 bytes */
+ {
+ U32 cached = ZSTD_read32(ip);
+ ip += 4;
+ while (ip < iend - 15) {
+ U32 c = cached;
+ cached = ZSTD_read32(ip);
+ ip += 4;
+ Counting1[(BYTE)c]++;
+ Counting2[(BYTE)(c >> 8)]++;
+ Counting3[(BYTE)(c >> 16)]++;
+ Counting4[c >> 24]++;
+ c = cached;
+ cached = ZSTD_read32(ip);
+ ip += 4;
+ Counting1[(BYTE)c]++;
+ Counting2[(BYTE)(c >> 8)]++;
+ Counting3[(BYTE)(c >> 16)]++;
+ Counting4[c >> 24]++;
+ c = cached;
+ cached = ZSTD_read32(ip);
+ ip += 4;
+ Counting1[(BYTE)c]++;
+ Counting2[(BYTE)(c >> 8)]++;
+ Counting3[(BYTE)(c >> 16)]++;
+ Counting4[c >> 24]++;
+ c = cached;
+ cached = ZSTD_read32(ip);
+ ip += 4;
+ Counting1[(BYTE)c]++;
+ Counting2[(BYTE)(c >> 8)]++;
+ Counting3[(BYTE)(c >> 16)]++;
+ Counting4[c >> 24]++;
+ }
+ ip -= 4;
+ }
+
+ /* finish last symbols */
+ while (ip < iend)
+ Counting1[*ip++]++;
+
+ if (checkMax) { /* verify stats will fit into destination table */
+ U32 s;
+ for (s = 255; s > maxSymbolValue; s--) {
+ Counting1[s] += Counting2[s] + Counting3[s] + Counting4[s];
+ if (Counting1[s])
+ return ERROR(maxSymbolValue_tooSmall);
+ }
+ }
+
+ {
+ U32 s;
+ for (s = 0; s <= maxSymbolValue; s++) {
+ count[s] = Counting1[s] + Counting2[s] + Counting3[s] + Counting4[s];
+ if (count[s] > max)
+ max = count[s];
+ }
+ }
+
+ while (!count[maxSymbolValue])
+ maxSymbolValue--;
+ *maxSymbolValuePtr = maxSymbolValue;
+ return (size_t)max;
+}
+
+/* FSE_countFast_wksp() :
+ * Same as FSE_countFast(), but using an externally provided scratch buffer.
+ * `workSpace` size must be table of >= `1024` unsigned */
+size_t FSE_countFast_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *source, size_t sourceSize, unsigned *workSpace)
+{
+ if (sourceSize < 1500)
+ return FSE_count_simple(count, maxSymbolValuePtr, source, sourceSize);
+ return FSE_count_parallel_wksp(count, maxSymbolValuePtr, source, sourceSize, 0, workSpace);
+}
+
+/* FSE_count_wksp() :
+ * Same as FSE_count(), but using an externally provided scratch buffer.
+ * `workSpace` size must be table of >= `1024` unsigned */
+size_t FSE_count_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *source, size_t sourceSize, unsigned *workSpace)
+{
+ if (*maxSymbolValuePtr < 255)
+ return FSE_count_parallel_wksp(count, maxSymbolValuePtr, source, sourceSize, 1, workSpace);
+ *maxSymbolValuePtr = 255;
+ return FSE_countFast_wksp(count, maxSymbolValuePtr, source, sourceSize, workSpace);
+}
+
+/*-**************************************************************
+* FSE Compression Code
+****************************************************************/
+/*! FSE_sizeof_CTable() :
+ FSE_CTable is a variable size structure which contains :
+ `U16 tableLog;`
+ `U16 maxSymbolValue;`
+ `U16 nextStateNumber[1 << tableLog];` // This size is variable
+ `FSE_symbolCompressionTransform symbolTT[maxSymbolValue+1];` // This size is variable
+Allocation is manual (C standard does not support variable-size structures).
+*/
+size_t FSE_sizeof_CTable(unsigned maxSymbolValue, unsigned tableLog)
+{
+ if (tableLog > FSE_MAX_TABLELOG)
+ return ERROR(tableLog_tooLarge);
+ return FSE_CTABLE_SIZE_U32(tableLog, maxSymbolValue) * sizeof(U32);
+}
+
+/* provides the minimum logSize to safely represent a distribution */
+static unsigned FSE_minTableLog(size_t srcSize, unsigned maxSymbolValue)
+{
+ U32 minBitsSrc = BIT_highbit32((U32)(srcSize - 1)) + 1;
+ U32 minBitsSymbols = BIT_highbit32(maxSymbolValue) + 2;
+ U32 minBits = minBitsSrc < minBitsSymbols ? minBitsSrc : minBitsSymbols;
+ return minBits;
+}
+
+unsigned FSE_optimalTableLog_internal(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, unsigned minus)
+{
+ U32 maxBitsSrc = BIT_highbit32((U32)(srcSize - 1)) - minus;
+ U32 tableLog = maxTableLog;
+ U32 minBits = FSE_minTableLog(srcSize, maxSymbolValue);
+ if (tableLog == 0)
+ tableLog = FSE_DEFAULT_TABLELOG;
+ if (maxBitsSrc < tableLog)
+ tableLog = maxBitsSrc; /* Accuracy can be reduced */
+ if (minBits > tableLog)
+ tableLog = minBits; /* Need a minimum to safely represent all symbol values */
+ if (tableLog < FSE_MIN_TABLELOG)
+ tableLog = FSE_MIN_TABLELOG;
+ if (tableLog > FSE_MAX_TABLELOG)
+ tableLog = FSE_MAX_TABLELOG;
+ return tableLog;
+}
+
+unsigned FSE_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue)
+{
+ return FSE_optimalTableLog_internal(maxTableLog, srcSize, maxSymbolValue, 2);
+}
+
+/* Secondary normalization method.
+ To be used when primary method fails. */
+
+static size_t FSE_normalizeM2(short *norm, U32 tableLog, const unsigned *count, size_t total, U32 maxSymbolValue)
+{
+ short const NOT_YET_ASSIGNED = -2;
+ U32 s;
+ U32 distributed = 0;
+ U32 ToDistribute;
+
+ /* Init */
+ U32 const lowThreshold = (U32)(total >> tableLog);
+ U32 lowOne = (U32)((total * 3) >> (tableLog + 1));
+
+ for (s = 0; s <= maxSymbolValue; s++) {
+ if (count[s] == 0) {
+ norm[s] = 0;
+ continue;
+ }
+ if (count[s] <= lowThreshold) {
+ norm[s] = -1;
+ distributed++;
+ total -= count[s];
+ continue;
+ }
+ if (count[s] <= lowOne) {
+ norm[s] = 1;
+ distributed++;
+ total -= count[s];
+ continue;
+ }
+
+ norm[s] = NOT_YET_ASSIGNED;
+ }
+ ToDistribute = (1 << tableLog) - distributed;
+
+ if ((total / ToDistribute) > lowOne) {
+ /* risk of rounding to zero */
+ lowOne = (U32)((total * 3) / (ToDistribute * 2));
+ for (s = 0; s <= maxSymbolValue; s++) {
+ if ((norm[s] == NOT_YET_ASSIGNED) && (count[s] <= lowOne)) {
+ norm[s] = 1;
+ distributed++;
+ total -= count[s];
+ continue;
+ }
+ }
+ ToDistribute = (1 << tableLog) - distributed;
+ }
+
+ if (distributed == maxSymbolValue + 1) {
+ /* all values are pretty poor;
+ probably incompressible data (should have already been detected);
+ find max, then give all remaining points to max */
+ U32 maxV = 0, maxC = 0;
+ for (s = 0; s <= maxSymbolValue; s++)
+ if (count[s] > maxC)
+ maxV = s, maxC = count[s];
+ norm[maxV] += (short)ToDistribute;
+ return 0;
+ }
+
+ if (total == 0) {
+ /* all of the symbols were low enough for the lowOne or lowThreshold */
+ for (s = 0; ToDistribute > 0; s = (s + 1) % (maxSymbolValue + 1))
+ if (norm[s] > 0)
+ ToDistribute--, norm[s]++;
+ return 0;
+ }
+
+ {
+ U64 const vStepLog = 62 - tableLog;
+ U64 const mid = (1ULL << (vStepLog - 1)) - 1;
+ U64 const rStep = div_u64((((U64)1 << vStepLog) * ToDistribute) + mid, (U32)total); /* scale on remaining */
+ U64 tmpTotal = mid;
+ for (s = 0; s <= maxSymbolValue; s++) {
+ if (norm[s] == NOT_YET_ASSIGNED) {
+ U64 const end = tmpTotal + (count[s] * rStep);
+ U32 const sStart = (U32)(tmpTotal >> vStepLog);
+ U32 const sEnd = (U32)(end >> vStepLog);
+ U32 const weight = sEnd - sStart;
+ if (weight < 1)
+ return ERROR(GENERIC);
+ norm[s] = (short)weight;
+ tmpTotal = end;
+ }
+ }
+ }
+
+ return 0;
+}
+
+size_t FSE_normalizeCount(short *normalizedCounter, unsigned tableLog, const unsigned *count, size_t total, unsigned maxSymbolValue)
+{
+ /* Sanity checks */
+ if (tableLog == 0)
+ tableLog = FSE_DEFAULT_TABLELOG;
+ if (tableLog < FSE_MIN_TABLELOG)
+ return ERROR(GENERIC); /* Unsupported size */
+ if (tableLog > FSE_MAX_TABLELOG)
+ return ERROR(tableLog_tooLarge); /* Unsupported size */
+ if (tableLog < FSE_minTableLog(total, maxSymbolValue))
+ return ERROR(GENERIC); /* Too small tableLog, compression potentially impossible */
+
+ {
+ U32 const rtbTable[] = {0, 473195, 504333, 520860, 550000, 700000, 750000, 830000};
+ U64 const scale = 62 - tableLog;
+ U64 const step = div_u64((U64)1 << 62, (U32)total); /* <== here, one division ! */
+ U64 const vStep = 1ULL << (scale - 20);
+ int stillToDistribute = 1 << tableLog;
+ unsigned s;
+ unsigned largest = 0;
+ short largestP = 0;
+ U32 lowThreshold = (U32)(total >> tableLog);
+
+ for (s = 0; s <= maxSymbolValue; s++) {
+ if (count[s] == total)
+ return 0; /* rle special case */
+ if (count[s] == 0) {
+ normalizedCounter[s] = 0;
+ continue;
+ }
+ if (count[s] <= lowThreshold) {
+ normalizedCounter[s] = -1;
+ stillToDistribute--;
+ } else {
+ short proba = (short)((count[s] * step) >> scale);
+ if (proba < 8) {
+ U64 restToBeat = vStep * rtbTable[proba];
+ proba += (count[s] * step) - ((U64)proba << scale) > restToBeat;
+ }
+ if (proba > largestP)
+ largestP = proba, largest = s;
+ normalizedCounter[s] = proba;
+ stillToDistribute -= proba;
+ }
+ }
+ if (-stillToDistribute >= (normalizedCounter[largest] >> 1)) {
+ /* corner case, need another normalization method */
+ size_t const errorCode = FSE_normalizeM2(normalizedCounter, tableLog, count, total, maxSymbolValue);
+ if (FSE_isError(errorCode))
+ return errorCode;
+ } else
+ normalizedCounter[largest] += (short)stillToDistribute;
+ }
+
+ return tableLog;
+}
+
+/* fake FSE_CTable, for raw (uncompressed) input */
+size_t FSE_buildCTable_raw(FSE_CTable *ct, unsigned nbBits)
+{
+ const unsigned tableSize = 1 << nbBits;
+ const unsigned tableMask = tableSize - 1;
+ const unsigned maxSymbolValue = tableMask;
+ void *const ptr = ct;
+ U16 *const tableU16 = ((U16 *)ptr) + 2;
+ void *const FSCT = ((U32 *)ptr) + 1 /* header */ + (tableSize >> 1); /* assumption : tableLog >= 1 */
+ FSE_symbolCompressionTransform *const symbolTT = (FSE_symbolCompressionTransform *)(FSCT);
+ unsigned s;
+
+ /* Sanity checks */
+ if (nbBits < 1)
+ return ERROR(GENERIC); /* min size */
+
+ /* header */
+ tableU16[-2] = (U16)nbBits;
+ tableU16[-1] = (U16)maxSymbolValue;
+
+ /* Build table */
+ for (s = 0; s < tableSize; s++)
+ tableU16[s] = (U16)(tableSize + s);
+
+ /* Build Symbol Transformation Table */
+ {
+ const U32 deltaNbBits = (nbBits << 16) - (1 << nbBits);
+ for (s = 0; s <= maxSymbolValue; s++) {
+ symbolTT[s].deltaNbBits = deltaNbBits;
+ symbolTT[s].deltaFindState = s - 1;
+ }
+ }
+
+ return 0;
+}
+
+/* fake FSE_CTable, for rle input (always same symbol) */
+size_t FSE_buildCTable_rle(FSE_CTable *ct, BYTE symbolValue)
+{
+ void *ptr = ct;
+ U16 *tableU16 = ((U16 *)ptr) + 2;
+ void *FSCTptr = (U32 *)ptr + 2;
+ FSE_symbolCompressionTransform *symbolTT = (FSE_symbolCompressionTransform *)FSCTptr;
+
+ /* header */
+ tableU16[-2] = (U16)0;
+ tableU16[-1] = (U16)symbolValue;
+
+ /* Build table */
+ tableU16[0] = 0;
+ tableU16[1] = 0; /* just in case */
+
+ /* Build Symbol Transformation Table */
+ symbolTT[symbolValue].deltaNbBits = 0;
+ symbolTT[symbolValue].deltaFindState = 0;
+
+ return 0;
+}
+
+static size_t FSE_compress_usingCTable_generic(void *dst, size_t dstSize, const void *src, size_t srcSize, const FSE_CTable *ct, const unsigned fast)
+{
+ const BYTE *const istart = (const BYTE *)src;
+ const BYTE *const iend = istart + srcSize;
+ const BYTE *ip = iend;
+
+ BIT_CStream_t bitC;
+ FSE_CState_t CState1, CState2;
+
+ /* init */
+ if (srcSize <= 2)
+ return 0;
+ {
+ size_t const initError = BIT_initCStream(&bitC, dst, dstSize);
+ if (FSE_isError(initError))
+ return 0; /* not enough space available to write a bitstream */
+ }
+
+#define FSE_FLUSHBITS(s) (fast ? BIT_flushBitsFast(s) : BIT_flushBits(s))
+
+ if (srcSize & 1) {
+ FSE_initCState2(&CState1, ct, *--ip);
+ FSE_initCState2(&CState2, ct, *--ip);
+ FSE_encodeSymbol(&bitC, &CState1, *--ip);
+ FSE_FLUSHBITS(&bitC);
+ } else {
+ FSE_initCState2(&CState2, ct, *--ip);
+ FSE_initCState2(&CState1, ct, *--ip);
+ }
+
+ /* join to mod 4 */
+ srcSize -= 2;
+ if ((sizeof(bitC.bitContainer) * 8 > FSE_MAX_TABLELOG * 4 + 7) && (srcSize & 2)) { /* test bit 2 */
+ FSE_encodeSymbol(&bitC, &CState2, *--ip);
+ FSE_encodeSymbol(&bitC, &CState1, *--ip);
+ FSE_FLUSHBITS(&bitC);
+ }
+
+ /* 2 or 4 encoding per loop */
+ while (ip > istart) {
+
+ FSE_encodeSymbol(&bitC, &CState2, *--ip);
+
+ if (sizeof(bitC.bitContainer) * 8 < FSE_MAX_TABLELOG * 2 + 7) /* this test must be static */
+ FSE_FLUSHBITS(&bitC);
+
+ FSE_encodeSymbol(&bitC, &CState1, *--ip);
+
+ if (sizeof(bitC.bitContainer) * 8 > FSE_MAX_TABLELOG * 4 + 7) { /* this test must be static */
+ FSE_encodeSymbol(&bitC, &CState2, *--ip);
+ FSE_encodeSymbol(&bitC, &CState1, *--ip);
+ }
+
+ FSE_FLUSHBITS(&bitC);
+ }
+
+ FSE_flushCState(&bitC, &CState2);
+ FSE_flushCState(&bitC, &CState1);
+ return BIT_closeCStream(&bitC);
+}
+
+size_t FSE_compress_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const FSE_CTable *ct)
+{
+ unsigned const fast = (dstSize >= FSE_BLOCKBOUND(srcSize));
+
+ if (fast)
+ return FSE_compress_usingCTable_generic(dst, dstSize, src, srcSize, ct, 1);
+ else
+ return FSE_compress_usingCTable_generic(dst, dstSize, src, srcSize, ct, 0);
+}
+
+size_t FSE_compressBound(size_t size) { return FSE_COMPRESSBOUND(size); }