diff options
Diffstat (limited to 'thirdparty/zstd/compress/fse_compress.c')
| -rw-r--r-- | thirdparty/zstd/compress/fse_compress.c | 131 |
1 files changed, 7 insertions, 124 deletions
diff --git a/thirdparty/zstd/compress/fse_compress.c b/thirdparty/zstd/compress/fse_compress.c index 5547b4ac09..5d3770808d 100644 --- a/thirdparty/zstd/compress/fse_compress.c +++ b/thirdparty/zstd/compress/fse_compress.c @@ -1,6 +1,6 @@ /* ****************************************************************** * FSE : Finite State Entropy encoder - * Copyright (c) Yann Collet, Facebook, Inc. + * Copyright (c) Meta Platforms, Inc. and affiliates. * * You can contact the author at : * - FSE source repository : https://github.com/Cyan4973/FiniteStateEntropy @@ -26,6 +26,7 @@ #define ZSTD_DEPS_NEED_MALLOC #define ZSTD_DEPS_NEED_MATH64 #include "../common/zstd_deps.h" /* ZSTD_malloc, ZSTD_free, ZSTD_memcpy, ZSTD_memset */ +#include "../common/bits.h" /* ZSTD_highbit32 */ /* ************************************************************** @@ -90,7 +91,7 @@ size_t FSE_buildCTable_wksp(FSE_CTable* ct, assert(tableLog < 16); /* required for threshold strategy to work */ /* For explanations on how to distribute symbol values over the table : - * http://fastcompression.blogspot.fr/2014/02/fse-distributing-symbol-values.html */ + * https://fastcompression.blogspot.fr/2014/02/fse-distributing-symbol-values.html */ #ifdef __clang_analyzer__ ZSTD_memset(tableSymbol, 0, sizeof(*tableSymbol) * tableSize); /* useless initialization, just to keep scan-build happy */ @@ -191,7 +192,7 @@ size_t FSE_buildCTable_wksp(FSE_CTable* ct, break; default : assert(normalizedCounter[s] > 1); - { U32 const maxBitsOut = tableLog - BIT_highbit32 ((U32)normalizedCounter[s]-1); + { U32 const maxBitsOut = tableLog - ZSTD_highbit32 ((U32)normalizedCounter[s]-1); U32 const minStatePlus = (U32)normalizedCounter[s] << maxBitsOut; symbolTT[s].deltaNbBits = (maxBitsOut << 16) - minStatePlus; symbolTT[s].deltaFindState = (int)(total - (unsigned)normalizedCounter[s]); @@ -342,21 +343,11 @@ size_t FSE_writeNCount (void* buffer, size_t bufferSize, * FSE Compression Code ****************************************************************/ -FSE_CTable* FSE_createCTable (unsigned maxSymbolValue, unsigned tableLog) -{ - size_t size; - if (tableLog > FSE_TABLELOG_ABSOLUTE_MAX) tableLog = FSE_TABLELOG_ABSOLUTE_MAX; - size = FSE_CTABLE_SIZE_U32 (tableLog, maxSymbolValue) * sizeof(U32); - return (FSE_CTable*)ZSTD_malloc(size); -} - -void FSE_freeCTable (FSE_CTable* ct) { ZSTD_free(ct); } - /* 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; - U32 minBitsSymbols = BIT_highbit32(maxSymbolValue) + 2; + U32 minBitsSrc = ZSTD_highbit32((U32)(srcSize)) + 1; + U32 minBitsSymbols = ZSTD_highbit32(maxSymbolValue) + 2; U32 minBits = minBitsSrc < minBitsSymbols ? minBitsSrc : minBitsSymbols; assert(srcSize > 1); /* Not supported, RLE should be used instead */ return minBits; @@ -364,7 +355,7 @@ static unsigned FSE_minTableLog(size_t srcSize, unsigned maxSymbolValue) unsigned FSE_optimalTableLog_internal(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, unsigned minus) { - U32 maxBitsSrc = BIT_highbit32((U32)(srcSize - 1)) - minus; + U32 maxBitsSrc = ZSTD_highbit32((U32)(srcSize - 1)) - minus; U32 tableLog = maxTableLog; U32 minBits = FSE_minTableLog(srcSize, maxSymbolValue); assert(srcSize > 1); /* Not supported, RLE should be used instead */ @@ -532,40 +523,6 @@ size_t FSE_normalizeCount (short* normalizedCounter, unsigned tableLog, 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) { @@ -664,78 +621,4 @@ size_t FSE_compress_usingCTable (void* dst, size_t dstSize, size_t FSE_compressBound(size_t size) { return FSE_COMPRESSBOUND(size); } -#ifndef ZSTD_NO_UNUSED_FUNCTIONS -/* FSE_compress_wksp() : - * Same as FSE_compress2(), but using an externally allocated scratch buffer (`workSpace`). - * `wkspSize` size must be `(1<<tableLog)`. - */ -size_t FSE_compress_wksp (void* dst, size_t dstSize, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void* workSpace, size_t wkspSize) -{ - BYTE* const ostart = (BYTE*) dst; - BYTE* op = ostart; - BYTE* const oend = ostart + dstSize; - - unsigned count[FSE_MAX_SYMBOL_VALUE+1]; - S16 norm[FSE_MAX_SYMBOL_VALUE+1]; - FSE_CTable* CTable = (FSE_CTable*)workSpace; - size_t const CTableSize = FSE_CTABLE_SIZE_U32(tableLog, maxSymbolValue); - void* scratchBuffer = (void*)(CTable + CTableSize); - size_t const scratchBufferSize = wkspSize - (CTableSize * sizeof(FSE_CTable)); - - /* init conditions */ - if (wkspSize < FSE_COMPRESS_WKSP_SIZE_U32(tableLog, maxSymbolValue)) return ERROR(tableLog_tooLarge); - if (srcSize <= 1) return 0; /* Not compressible */ - if (!maxSymbolValue) maxSymbolValue = FSE_MAX_SYMBOL_VALUE; - if (!tableLog) tableLog = FSE_DEFAULT_TABLELOG; - - /* Scan input and build symbol stats */ - { CHECK_V_F(maxCount, HIST_count_wksp(count, &maxSymbolValue, src, srcSize, scratchBuffer, scratchBufferSize) ); - 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 */ - } - - tableLog = FSE_optimalTableLog(tableLog, srcSize, maxSymbolValue); - CHECK_F( FSE_normalizeCount(norm, tableLog, count, srcSize, maxSymbolValue, /* useLowProbCount */ srcSize >= 2048) ); - - /* Write table description header */ - { CHECK_V_F(nc_err, FSE_writeNCount(op, oend-op, norm, maxSymbolValue, tableLog) ); - op += nc_err; - } - - /* Compress */ - CHECK_F( FSE_buildCTable_wksp(CTable, norm, maxSymbolValue, tableLog, scratchBuffer, scratchBufferSize) ); - { CHECK_V_F(cSize, FSE_compress_usingCTable(op, oend - op, src, srcSize, CTable) ); - if (cSize == 0) return 0; /* not enough space for compressed data */ - op += cSize; - } - - /* check compressibility */ - if ( (size_t)(op-ostart) >= srcSize-1 ) return 0; - - return op-ostart; -} - -typedef struct { - FSE_CTable CTable_max[FSE_CTABLE_SIZE_U32(FSE_MAX_TABLELOG, FSE_MAX_SYMBOL_VALUE)]; - union { - U32 hist_wksp[HIST_WKSP_SIZE_U32]; - BYTE scratchBuffer[1 << FSE_MAX_TABLELOG]; - } workspace; -} fseWkspMax_t; - -size_t FSE_compress2 (void* dst, size_t dstCapacity, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog) -{ - fseWkspMax_t scratchBuffer; - DEBUG_STATIC_ASSERT(sizeof(scratchBuffer) >= FSE_COMPRESS_WKSP_SIZE_U32(FSE_MAX_TABLELOG, FSE_MAX_SYMBOL_VALUE)); /* compilation failures here means scratchBuffer is not large enough */ - if (tableLog > FSE_MAX_TABLELOG) return ERROR(tableLog_tooLarge); - return FSE_compress_wksp(dst, dstCapacity, src, srcSize, maxSymbolValue, tableLog, &scratchBuffer, sizeof(scratchBuffer)); -} - -size_t FSE_compress (void* dst, size_t dstCapacity, const void* src, size_t srcSize) -{ - return FSE_compress2(dst, dstCapacity, src, srcSize, FSE_MAX_SYMBOL_VALUE, FSE_DEFAULT_TABLELOG); -} -#endif - #endif /* FSE_COMMONDEFS_ONLY */ |