- Public forum : https://groups.google.com/forum/#!forum/lz4c
****************************************************************** */
-/* **************************************************************
-* Compiler specifics
-****************************************************************/
-#ifdef _MSC_VER /* Visual Studio */
-# define FORCE_INLINE static __forceinline
-# include <intrin.h> /* For Visual 2005 */
-# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
-# pragma warning(disable : 4214) /* disable: C4214: non-int bitfields */
-#else
-# if defined (__cplusplus) || defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */
-# ifdef __GNUC__
-# define FORCE_INLINE static inline __attribute__((always_inline))
-# else
-# define FORCE_INLINE static inline
-# endif
-# else
-# define FORCE_INLINE static
-# endif /* __STDC_VERSION__ */
-#endif
-
-
/* **************************************************************
* Includes
****************************************************************/
#include <string.h> /* memcpy, memset */
#include <stdio.h> /* printf (debug) */
#include "bitstream.h"
+#include "compiler.h"
#define FSE_STATIC_LINKING_ONLY
#include "fse.h"
+#include "error_private.h"
/* **************************************************************
* Error Management
****************************************************************/
+#define FSE_isError ERR_isError
#define FSE_STATIC_ASSERT(c) { enum { FSE_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */
return maxSymbolValue ? maxHeaderSize : FSE_NCOUNTBOUND; /* maxSymbolValue==0 ? use default */
}
-static short FSE_abs(short a) { return (short)(a<0 ? -a : a); }
-
static size_t FSE_writeNCount_generic (void* header, size_t headerBufferSize,
const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog,
unsigned writeIsSafe)
bitStream >>= 16;
bitCount -= 16;
} }
- { short count = normalizedCounter[charnum++];
- const short max = (short)((2*threshold-1)-remaining);
- remaining -= FSE_abs(count);
- if (remaining<1) return ERROR(GENERIC);
+ { 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) {
size_t FSE_writeNCount (void* buffer, size_t bufferSize, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog)
{
- if (tableLog > FSE_MAX_TABLELOG) return ERROR(GENERIC); /* Unsupported */
+ 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))
/* 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;
+ U32 minBitsSrc = BIT_highbit32((U32)(srcSize - 1)) + 1;
+ U32 minBitsSymbols = BIT_highbit32(maxSymbolValue) + 2;
+ U32 minBits = minBitsSrc < minBitsSymbols ? minBitsSrc : minBitsSymbols;
+ assert(srcSize > 1); /* Not supported, RLE should be used instead */
+ return minBits;
}
unsigned FSE_optimalTableLog_internal(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, unsigned minus)
{
- U32 maxBitsSrc = BIT_highbit32((U32)(srcSize - 1)) - minus;
+ U32 maxBitsSrc = BIT_highbit32((U32)(srcSize - 1)) - minus;
U32 tableLog = maxTableLog;
- U32 minBits = FSE_minTableLog(srcSize, maxSymbolValue);
+ U32 minBits = FSE_minTableLog(srcSize, maxSymbolValue);
+ assert(srcSize > 1); /* Not supported, RLE should be used instead */
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 (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;
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;
total -= count[s];
continue;
}
- norm[s]=-2;
+
+ norm[s]=NOT_YET_ASSIGNED;
}
ToDistribute = (1 << tableLog) - distributed;
/* risk of rounding to zero */
lowOne = (U32)((total * 3) / (ToDistribute * 2));
for (s=0; s<=maxSymbolValue; s++) {
- if ((norm[s] == -2) && (count[s] <= lowOne)) {
+ if ((norm[s] == NOT_YET_ASSIGNED) && (count[s] <= lowOne)) {
norm[s] = 1;
distributed++;
total -= count[s];
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 = ((((U64)1<<vStepLog) * ToDistribute) + mid) / total; /* scale on remaining */
U64 tmpTotal = mid;
for (s=0; s<=maxSymbolValue; s++) {
- if (norm[s]==-2) {
+ 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);
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 };
+ { static U32 const rtbTable[] = { 0, 473195, 504333, 520860, 550000, 700000, 750000, 830000 };
U64 const scale = 62 - tableLog;
U64 const step = ((U64)1<<62) / total; /* <== here, one division ! */
U64 const vStep = 1ULL<<(scale-20);
size_t FSE_compressBound(size_t size) { return FSE_COMPRESSBOUND(size); }
-#define CHECK_V_F(e, f) size_t const e = f; if (ERR_isError(e)) return f
+#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); }
/* FSE_compress_wksp() :
if (!tableLog) tableLog = FSE_DEFAULT_TABLELOG;
/* Scan input and build symbol stats */
- { CHECK_V_F(maxCount, FSE_count(count, &maxSymbolValue, src, srcSize) );
+ { CHECK_V_F(maxCount, FSE_count_wksp(count, &maxSymbolValue, src, srcSize, (unsigned*)scratchBuffer) );
if (maxCount == srcSize) return 1; /* only a single symbol in src : rle */
if (maxCount == 1) return 0; /* each symbol present maximum once => not compressible */
if (maxCount < (srcSize >> 7)) return 0; /* Heuristic : not compressible enough */
projects / ceph.git / blobdiff