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Diffstat (limited to 'lib/zstd/common/entropy_common.c')
| -rw-r--r-- | lib/zstd/common/entropy_common.c | 357 |
1 files changed, 0 insertions, 357 deletions
diff --git a/lib/zstd/common/entropy_common.c b/lib/zstd/common/entropy_common.c deleted file mode 100644 index 53b47a2b52..0000000000 --- a/lib/zstd/common/entropy_common.c +++ /dev/null @@ -1,357 +0,0 @@ -/* ****************************************************************** - * Common functions of New Generation Entropy library - * Copyright (c) Yann Collet, Facebook, Inc. - * - * You can contact the author at : - * - FSE+HUF source repository : https://github.com/Cyan4973/FiniteStateEntropy - * - Public forum : https://groups.google.com/forum/#!forum/lz4c - * - * This source code is licensed under both the BSD-style license (found in the - * LICENSE file in the root directory of this source tree) and the GPLv2 (found - * in the COPYING file in the root directory of this source tree). - * You may select, at your option, one of the above-listed licenses. -****************************************************************** */ - -/* ************************************* -* Dependencies -***************************************/ -#include "mem.h" -#include "error_private.h" /* ERR_*, ERROR */ -#define FSE_STATIC_LINKING_ONLY /* FSE_MIN_TABLELOG */ -#include "fse.h" -#define HUF_STATIC_LINKING_ONLY /* HUF_TABLELOG_ABSOLUTEMAX */ -#include "huf.h" - - -/*=== Version ===*/ -unsigned FSE_versionNumber(void) { return FSE_VERSION_NUMBER; } - - -/*=== Error Management ===*/ -unsigned FSE_isError(size_t code) { return ERR_isError(code); } -const char* FSE_getErrorName(size_t code) { return ERR_getErrorName(code); } - -unsigned HUF_isError(size_t code) { return ERR_isError(code); } -const char* HUF_getErrorName(size_t code) { return ERR_getErrorName(code); } - - -/*-************************************************************** -* FSE NCount encoding-decoding -****************************************************************/ -static U32 FSE_ctz(U32 val) -{ - assert(val != 0); - { -# if (__GNUC__ >= 3) /* GCC Intrinsic */ - return __builtin_ctz(val); -# else /* Software version */ - U32 count = 0; - while ((val & 1) == 0) { - val >>= 1; - ++count; - } - return count; -# endif - } -} - -FORCE_INLINE_TEMPLATE -size_t FSE_readNCount_body(short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr, - const void* headerBuffer, size_t hbSize) -{ - const BYTE* const istart = (const BYTE*) headerBuffer; - const BYTE* const iend = istart + hbSize; - const BYTE* ip = istart; - int nbBits; - int remaining; - int threshold; - U32 bitStream; - int bitCount; - unsigned charnum = 0; - unsigned const maxSV1 = *maxSVPtr + 1; - int previous0 = 0; - - if (hbSize < 8) { - /* This function only works when hbSize >= 8 */ - char buffer[8] = {0}; - ZSTD_memcpy(buffer, headerBuffer, hbSize); - { size_t const countSize = FSE_readNCount(normalizedCounter, maxSVPtr, tableLogPtr, - buffer, sizeof(buffer)); - if (FSE_isError(countSize)) return countSize; - if (countSize > hbSize) return ERROR(corruption_detected); - return countSize; - } } - assert(hbSize >= 8); - - /* init */ - ZSTD_memset(normalizedCounter, 0, (*maxSVPtr+1) * sizeof(normalizedCounter[0])); /* all symbols not present in NCount have a frequency of 0 */ - bitStream = MEM_readLE32(ip); - nbBits = (bitStream & 0xF) + FSE_MIN_TABLELOG; /* extract tableLog */ - if (nbBits > FSE_TABLELOG_ABSOLUTE_MAX) return ERROR(tableLog_tooLarge); - bitStream >>= 4; - bitCount = 4; - *tableLogPtr = nbBits; - remaining = (1<<nbBits)+1; - threshold = 1<<nbBits; - nbBits++; - - for (;;) { - if (previous0) { - /* Count the number of repeats. Each time the - * 2-bit repeat code is 0b11 there is another - * repeat. - * Avoid UB by setting the high bit to 1. - */ - int repeats = FSE_ctz(~bitStream | 0x80000000) >> 1; - while (repeats >= 12) { - charnum += 3 * 12; - if (LIKELY(ip <= iend-7)) { - ip += 3; - } else { - bitCount -= (int)(8 * (iend - 7 - ip)); - bitCount &= 31; - ip = iend - 4; - } - bitStream = MEM_readLE32(ip) >> bitCount; - repeats = FSE_ctz(~bitStream | 0x80000000) >> 1; - } - charnum += 3 * repeats; - bitStream >>= 2 * repeats; - bitCount += 2 * repeats; - - /* Add the final repeat which isn't 0b11. */ - assert((bitStream & 3) < 3); - charnum += bitStream & 3; - bitCount += 2; - - /* This is an error, but break and return an error - * at the end, because returning out of a loop makes - * it harder for the compiler to optimize. - */ - if (charnum >= maxSV1) break; - - /* We don't need to set the normalized count to 0 - * because we already memset the whole buffer to 0. - */ - - if (LIKELY(ip <= iend-7) || (ip + (bitCount>>3) <= iend-4)) { - assert((bitCount >> 3) <= 3); /* For first condition to work */ - ip += bitCount>>3; - bitCount &= 7; - } else { - bitCount -= (int)(8 * (iend - 4 - ip)); - bitCount &= 31; - ip = iend - 4; - } - bitStream = MEM_readLE32(ip) >> bitCount; - } - { - int const max = (2*threshold-1) - remaining; - int count; - - if ((bitStream & (threshold-1)) < (U32)max) { - count = bitStream & (threshold-1); - bitCount += nbBits-1; - } else { - count = bitStream & (2*threshold-1); - if (count >= threshold) count -= max; - bitCount += nbBits; - } - - count--; /* extra accuracy */ - /* When it matters (small blocks), this is a - * predictable branch, because we don't use -1. - */ - if (count >= 0) { - remaining -= count; - } else { - assert(count == -1); - remaining += count; - } - normalizedCounter[charnum++] = (short)count; - previous0 = !count; - - assert(threshold > 1); - if (remaining < threshold) { - /* This branch can be folded into the - * threshold update condition because we - * know that threshold > 1. - */ - if (remaining <= 1) break; - nbBits = BIT_highbit32(remaining) + 1; - threshold = 1 << (nbBits - 1); - } - if (charnum >= maxSV1) break; - - if (LIKELY(ip <= iend-7) || (ip + (bitCount>>3) <= iend-4)) { - ip += bitCount>>3; - bitCount &= 7; - } else { - bitCount -= (int)(8 * (iend - 4 - ip)); - bitCount &= 31; - ip = iend - 4; - } - bitStream = MEM_readLE32(ip) >> bitCount; - } } - if (remaining != 1) return ERROR(corruption_detected); - /* Only possible when there are too many zeros. */ - if (charnum > maxSV1) return ERROR(maxSymbolValue_tooSmall); - if (bitCount > 32) return ERROR(corruption_detected); - *maxSVPtr = charnum-1; - - ip += (bitCount+7)>>3; - return ip-istart; -} - -/* Avoids the FORCE_INLINE of the _body() function. */ -static size_t FSE_readNCount_body_default( - short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr, - const void* headerBuffer, size_t hbSize) -{ - return FSE_readNCount_body(normalizedCounter, maxSVPtr, tableLogPtr, headerBuffer, hbSize); -} - -#if DYNAMIC_BMI2 -TARGET_ATTRIBUTE("bmi2") static size_t FSE_readNCount_body_bmi2( - short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr, - const void* headerBuffer, size_t hbSize) -{ - return FSE_readNCount_body(normalizedCounter, maxSVPtr, tableLogPtr, headerBuffer, hbSize); -} -#endif - -size_t FSE_readNCount_bmi2( - short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr, - const void* headerBuffer, size_t hbSize, int bmi2) -{ -#if DYNAMIC_BMI2 - if (bmi2) { - return FSE_readNCount_body_bmi2(normalizedCounter, maxSVPtr, tableLogPtr, headerBuffer, hbSize); - } -#endif - (void)bmi2; - return FSE_readNCount_body_default(normalizedCounter, maxSVPtr, tableLogPtr, headerBuffer, hbSize); -} - -size_t FSE_readNCount( - short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr, - const void* headerBuffer, size_t hbSize) -{ - return FSE_readNCount_bmi2(normalizedCounter, maxSVPtr, tableLogPtr, headerBuffer, hbSize, /* bmi2 */ 0); -} - - -/*! HUF_readStats() : - Read compact Huffman tree, saved by HUF_writeCTable(). - `huffWeight` is destination buffer. - `rankStats` is assumed to be a table of at least HUF_TABLELOG_MAX U32. - @return : size read from `src` , or an error Code . - Note : Needed by HUF_readCTable() and HUF_readDTableX?() . -*/ -size_t HUF_readStats(BYTE* huffWeight, size_t hwSize, U32* rankStats, - U32* nbSymbolsPtr, U32* tableLogPtr, - const void* src, size_t srcSize) -{ - U32 wksp[HUF_READ_STATS_WORKSPACE_SIZE_U32]; - return HUF_readStats_wksp(huffWeight, hwSize, rankStats, nbSymbolsPtr, tableLogPtr, src, srcSize, wksp, sizeof(wksp), /* bmi2 */ 0); -} - -FORCE_INLINE_TEMPLATE size_t -HUF_readStats_body(BYTE* huffWeight, size_t hwSize, U32* rankStats, - U32* nbSymbolsPtr, U32* tableLogPtr, - const void* src, size_t srcSize, - void* workSpace, size_t wkspSize, - int bmi2) -{ - U32 weightTotal; - const BYTE* ip = (const BYTE*) src; - size_t iSize; - size_t oSize; - - if (!srcSize) return ERROR(srcSize_wrong); - iSize = ip[0]; - /* ZSTD_memset(huffWeight, 0, hwSize); *//* is not necessary, even though some analyzer complain ... */ - - if (iSize >= 128) { /* special header */ - oSize = iSize - 127; - iSize = ((oSize+1)/2); - if (iSize+1 > srcSize) return ERROR(srcSize_wrong); - if (oSize >= hwSize) return ERROR(corruption_detected); - ip += 1; - { U32 n; - for (n=0; n<oSize; n+=2) { - huffWeight[n] = ip[n/2] >> 4; - huffWeight[n+1] = ip[n/2] & 15; - } } } - else { /* header compressed with FSE (normal case) */ - if (iSize+1 > srcSize) return ERROR(srcSize_wrong); - /* max (hwSize-1) values decoded, as last one is implied */ - oSize = FSE_decompress_wksp_bmi2(huffWeight, hwSize-1, ip+1, iSize, 6, workSpace, wkspSize, bmi2); - if (FSE_isError(oSize)) return oSize; - } - - /* collect weight stats */ - ZSTD_memset(rankStats, 0, (HUF_TABLELOG_MAX + 1) * sizeof(U32)); - weightTotal = 0; - { U32 n; for (n=0; n<oSize; n++) { - if (huffWeight[n] >= HUF_TABLELOG_MAX) return ERROR(corruption_detected); - rankStats[huffWeight[n]]++; - weightTotal += (1 << huffWeight[n]) >> 1; - } } - if (weightTotal == 0) return ERROR(corruption_detected); - - /* get last non-null symbol weight (implied, total must be 2^n) */ - { U32 const tableLog = BIT_highbit32(weightTotal) + 1; - if (tableLog > HUF_TABLELOG_MAX) return ERROR(corruption_detected); - *tableLogPtr = tableLog; - /* determine last weight */ - { U32 const total = 1 << tableLog; - U32 const rest = total - weightTotal; - U32 const verif = 1 << BIT_highbit32(rest); - U32 const lastWeight = BIT_highbit32(rest) + 1; - if (verif != rest) return ERROR(corruption_detected); /* last value must be a clean power of 2 */ - huffWeight[oSize] = (BYTE)lastWeight; - rankStats[lastWeight]++; - } } - - /* check tree construction validity */ - if ((rankStats[1] < 2) || (rankStats[1] & 1)) return ERROR(corruption_detected); /* by construction : at least 2 elts of rank 1, must be even */ - - /* results */ - *nbSymbolsPtr = (U32)(oSize+1); - return iSize+1; -} - -/* Avoids the FORCE_INLINE of the _body() function. */ -static size_t HUF_readStats_body_default(BYTE* huffWeight, size_t hwSize, U32* rankStats, - U32* nbSymbolsPtr, U32* tableLogPtr, - const void* src, size_t srcSize, - void* workSpace, size_t wkspSize) -{ - return HUF_readStats_body(huffWeight, hwSize, rankStats, nbSymbolsPtr, tableLogPtr, src, srcSize, workSpace, wkspSize, 0); -} - -#if DYNAMIC_BMI2 -static TARGET_ATTRIBUTE("bmi2") size_t HUF_readStats_body_bmi2(BYTE* huffWeight, size_t hwSize, U32* rankStats, - U32* nbSymbolsPtr, U32* tableLogPtr, - const void* src, size_t srcSize, - void* workSpace, size_t wkspSize) -{ - return HUF_readStats_body(huffWeight, hwSize, rankStats, nbSymbolsPtr, tableLogPtr, src, srcSize, workSpace, wkspSize, 1); -} -#endif - -size_t HUF_readStats_wksp(BYTE* huffWeight, size_t hwSize, U32* rankStats, - U32* nbSymbolsPtr, U32* tableLogPtr, - const void* src, size_t srcSize, - void* workSpace, size_t wkspSize, - int bmi2) -{ -#if DYNAMIC_BMI2 - if (bmi2) { - return HUF_readStats_body_bmi2(huffWeight, hwSize, rankStats, nbSymbolsPtr, tableLogPtr, src, srcSize, workSpace, wkspSize); - } -#endif - (void)bmi2; - return HUF_readStats_body_default(huffWeight, hwSize, rankStats, nbSymbolsPtr, tableLogPtr, src, srcSize, workSpace, wkspSize); -} |