1613 lines
52 KiB
C
1613 lines
52 KiB
C
/* ******************************************************************
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FSE : Finite State Entropy coder
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Copyright (C) 2013-2015, Yann Collet.
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BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
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Redistribution and use in source and binary forms, with or without
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modification, are permitted provided that the following conditions are
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met:
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* Redistributions of source code must retain the above copyright
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notice, this list of conditions and the following disclaimer.
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* Redistributions in binary form must reproduce the above
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copyright notice, this list of conditions and the following disclaimer
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in the documentation and/or other materials provided with the
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distribution.
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THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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You can contact the author at :
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- FSE source repository : https://github.com/Cyan4973/FiniteStateEntropy
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- Public forum : https://groups.google.com/forum/#!forum/lz4c
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****************************************************************** */
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#ifndef FSE_COMMONDEFS_ONLY
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/****************************************************************
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* Tuning parameters
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****************************************************************/
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/* MEMORY_USAGE :
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* Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
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* Increasing memory usage improves compression ratio
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* Reduced memory usage can improve speed, due to cache effect
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* Recommended max value is 14, for 16KB, which nicely fits into Intel x86 L1 cache */
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#define FSE_MAX_MEMORY_USAGE 14
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#define FSE_DEFAULT_MEMORY_USAGE 13
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/* FSE_MAX_SYMBOL_VALUE :
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* Maximum symbol value authorized.
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* Required for proper stack allocation */
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#define FSE_MAX_SYMBOL_VALUE 255
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/****************************************************************
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* Generic function type & suffix (C template emulation)
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****************************************************************/
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#define FSE_FUNCTION_TYPE BYTE
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#define FSE_FUNCTION_EXTENSION
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#endif /* !FSE_COMMONDEFS_ONLY */
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/****************************************************************
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* Compiler specifics
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****************************************************************/
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#ifdef _MSC_VER /* Visual Studio */
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# define FORCE_INLINE static __forceinline
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# include <intrin.h> /* For Visual 2005 */
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# pragma warning(disable : 4127) /* disable: C4127: conditional expression is constant */
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# pragma warning(disable : 4214) /* disable: C4214: non-int bitfields */
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#else
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# define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
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# ifdef __GNUC__
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# define FORCE_INLINE static inline __attribute__((always_inline))
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# else
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# define FORCE_INLINE static inline
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# endif
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#endif
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/****************************************************************
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* Includes
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****************************************************************/
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#include <stdlib.h> /* malloc, free, qsort */
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#include <string.h> /* memcpy, memset */
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#include <stdio.h> /* printf (debug) */
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#include "fse_static.h"
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#ifndef MEM_ACCESS_MODULE
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#define MEM_ACCESS_MODULE
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/****************************************************************
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* Basic Types
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*****************************************************************/
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#if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L /* C99 */
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# include <stdint.h>
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typedef uint8_t BYTE;
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typedef uint16_t U16;
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typedef int16_t S16;
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typedef uint32_t U32;
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typedef int32_t S32;
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typedef uint64_t U64;
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typedef int64_t S64;
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#else
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typedef unsigned char BYTE;
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typedef unsigned short U16;
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typedef signed short S16;
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typedef unsigned int U32;
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typedef signed int S32;
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typedef unsigned long long U64;
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typedef signed long long S64;
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#endif
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#endif /* MEM_ACCESS_MODULE */
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/****************************************************************
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* Memory I/O
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*****************************************************************/
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static unsigned FSE_isLittleEndian(void)
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{
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const union { U32 i; BYTE c[4]; } one = { 1 }; /* don't use static : performance detrimental */
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return one.c[0];
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}
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static U32 FSE_read32(const void* memPtr)
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{
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U32 val32;
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memcpy(&val32, memPtr, 4);
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return val32;
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}
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static U32 FSE_readLE32(const void* memPtr)
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{
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if (FSE_isLittleEndian())
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return FSE_read32(memPtr);
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else
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{
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const BYTE* p = (const BYTE*)memPtr;
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return (U32)((U32)p[0] + ((U32)p[1]<<8) + ((U32)p[2]<<16) + ((U32)p[3]<<24));
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}
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}
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static void FSE_writeLE32(void* memPtr, U32 val32)
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{
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if (FSE_isLittleEndian())
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{
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memcpy(memPtr, &val32, 4);
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}
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else
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{
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BYTE* p = (BYTE*)memPtr;
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p[0] = (BYTE)val32;
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p[1] = (BYTE)(val32>>8);
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p[2] = (BYTE)(val32>>16);
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p[3] = (BYTE)(val32>>24);
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}
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}
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static U64 FSE_read64(const void* memPtr)
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{
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U64 val64;
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memcpy(&val64, memPtr, 8);
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return val64;
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}
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static U64 FSE_readLE64(const void* memPtr)
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{
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if (FSE_isLittleEndian())
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return FSE_read64(memPtr);
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else
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{
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const BYTE* p = (const BYTE*)memPtr;
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return (U64)((U64)p[0] + ((U64)p[1]<<8) + ((U64)p[2]<<16) + ((U64)p[3]<<24)
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+ ((U64)p[4]<<32) + ((U64)p[5]<<40) + ((U64)p[6]<<48) + ((U64)p[7]<<56));
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}
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}
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static void FSE_writeLE64(void* memPtr, U64 val64)
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{
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if (FSE_isLittleEndian())
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{
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memcpy(memPtr, &val64, 8);
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}
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else
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{
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BYTE* p = (BYTE*)memPtr;
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p[0] = (BYTE)val64;
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p[1] = (BYTE)(val64>>8);
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p[2] = (BYTE)(val64>>16);
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p[3] = (BYTE)(val64>>24);
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p[4] = (BYTE)(val64>>32);
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p[5] = (BYTE)(val64>>40);
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p[6] = (BYTE)(val64>>48);
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p[7] = (BYTE)(val64>>56);
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}
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}
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static size_t FSE_readLEST(const void* memPtr)
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{
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if (sizeof(size_t)==4)
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return (size_t)FSE_readLE32(memPtr);
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else
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return (size_t)FSE_readLE64(memPtr);
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}
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static void FSE_writeLEST(void* memPtr, size_t val)
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{
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if (sizeof(size_t)==4)
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FSE_writeLE32(memPtr, (U32)val);
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else
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FSE_writeLE64(memPtr, (U64)val);
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}
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/****************************************************************
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* Constants
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*****************************************************************/
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#define FSE_MAX_TABLELOG (FSE_MAX_MEMORY_USAGE-2)
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#define FSE_MAX_TABLESIZE (1U<<FSE_MAX_TABLELOG)
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#define FSE_MAXTABLESIZE_MASK (FSE_MAX_TABLESIZE-1)
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#define FSE_DEFAULT_TABLELOG (FSE_DEFAULT_MEMORY_USAGE-2)
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#define FSE_MIN_TABLELOG 5
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#define FSE_TABLELOG_ABSOLUTE_MAX 15
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#if FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX
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#error "FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX is not supported"
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#endif
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/****************************************************************
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* Error Management
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****************************************************************/
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#define FSE_STATIC_ASSERT(c) { enum { FSE_static_assert = 1/(int)(!!(c)) }; } /* use only *after* variable declarations */
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/****************************************************************
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* Complex types
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****************************************************************/
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typedef struct
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{
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int deltaFindState;
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U16 maxState;
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BYTE minBitsOut;
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/* one byte padding ; total 8 bytes */
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} FSE_symbolCompressionTransform;
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typedef U32 CTable_max_t[FSE_CTABLE_SIZE_U32(FSE_MAX_TABLELOG, FSE_MAX_SYMBOL_VALUE)];
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typedef U32 DTable_max_t[FSE_DTABLE_SIZE_U32(FSE_MAX_TABLELOG)];
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/****************************************************************
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* Internal functions
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****************************************************************/
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FORCE_INLINE unsigned FSE_highbit32 (register U32 val)
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{
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# if defined(_MSC_VER) /* Visual */
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unsigned long r;
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_BitScanReverse ( &r, val );
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return (unsigned) r;
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# elif defined(__GNUC__) && (GCC_VERSION >= 304) /* GCC Intrinsic */
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return 31 - __builtin_clz (val);
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# else /* Software version */
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static const unsigned DeBruijnClz[32] = { 0, 9, 1, 10, 13, 21, 2, 29, 11, 14, 16, 18, 22, 25, 3, 30, 8, 12, 20, 28, 15, 17, 24, 7, 19, 27, 23, 6, 26, 5, 4, 31 };
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U32 v = val;
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unsigned r;
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v |= v >> 1;
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v |= v >> 2;
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v |= v >> 4;
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v |= v >> 8;
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v |= v >> 16;
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r = DeBruijnClz[ (U32) (v * 0x07C4ACDDU) >> 27];
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return r;
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# endif
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}
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#ifndef FSE_COMMONDEFS_ONLY
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unsigned FSE_isError(size_t code) { return (code > (size_t)(-FSE_ERROR_maxCode)); }
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#define FSE_GENERATE_STRING(STRING) #STRING,
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static const char* FSE_errorStrings[] = { FSE_LIST_ERRORS(FSE_GENERATE_STRING) };
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const char* FSE_getErrorName(size_t code)
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{
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static const char* codeError = "Unspecified error code";
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if (FSE_isError(code)) return FSE_errorStrings[-(int)(code)];
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return codeError;
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}
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static short FSE_abs(short a)
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{
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return a<0? -a : a;
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}
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/****************************************************************
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* Header bitstream management
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****************************************************************/
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size_t FSE_NCountWriteBound(unsigned maxSymbolValue, unsigned tableLog)
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{
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size_t maxHeaderSize = (((maxSymbolValue+1) * tableLog) >> 3) + 1;
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return maxSymbolValue ? maxHeaderSize : FSE_MAX_HEADERSIZE;
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}
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#ifndef __clang_analyzer__ /* clang static analyzer has difficulties with this function : seems to believe normalizedCounter is uninitialized */
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static size_t FSE_writeNCount_generic (void* header, size_t headerBufferSize,
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const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog,
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unsigned safeWrite)
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{
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BYTE* const ostart = (BYTE*) header;
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BYTE* out = ostart;
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BYTE* const oend = ostart + headerBufferSize;
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int nbBits;
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const int tableSize = 1 << tableLog;
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int remaining;
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int threshold;
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U32 bitStream;
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int bitCount;
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unsigned charnum = 0;
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int previous0 = 0;
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bitStream = 0;
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bitCount = 0;
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/* Table Size */
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bitStream += (tableLog-FSE_MIN_TABLELOG) << bitCount;
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bitCount += 4;
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/* Init */
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remaining = tableSize+1; /* +1 for extra accuracy */
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threshold = tableSize;
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nbBits = tableLog+1;
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while (remaining>1) /* stops at 1 */
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{
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if (previous0)
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{
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unsigned start = charnum;
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while (!normalizedCounter[charnum]) charnum++;
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while (charnum >= start+24)
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{
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start+=24;
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bitStream += 0xFFFFU << bitCount;
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if ((!safeWrite) && (out > oend-2)) return (size_t)-FSE_ERROR_GENERIC; /* Buffer overflow */
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out[0] = (BYTE) bitStream;
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out[1] = (BYTE)(bitStream>>8);
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out+=2;
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bitStream>>=16;
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}
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while (charnum >= start+3)
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{
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start+=3;
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bitStream += 3 << bitCount;
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bitCount += 2;
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}
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bitStream += (charnum-start) << bitCount;
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bitCount += 2;
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if (bitCount>16)
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{
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if ((!safeWrite) && (out > oend - 2)) return (size_t)-FSE_ERROR_GENERIC; /* Buffer overflow */
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out[0] = (BYTE)bitStream;
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out[1] = (BYTE)(bitStream>>8);
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out += 2;
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bitStream >>= 16;
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bitCount -= 16;
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}
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}
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{
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short count = normalizedCounter[charnum++];
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const short max = (short)((2*threshold-1)-remaining);
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remaining -= FSE_abs(count);
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if (remaining<1) return (size_t)-FSE_ERROR_GENERIC;
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count++; /* +1 for extra accuracy */
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if (count>=threshold) count += max; /* [0..max[ [max..threshold[ (...) [threshold+max 2*threshold[ */
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bitStream += count << bitCount;
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bitCount += nbBits;
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bitCount -= (count<max);
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previous0 = (count==1);
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while (remaining<threshold) nbBits--, threshold>>=1;
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}
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if (bitCount>16)
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{
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if ((!safeWrite) && (out > oend - 2)) return (size_t)-FSE_ERROR_GENERIC; /* Buffer overflow */
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out[0] = (BYTE)bitStream;
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out[1] = (BYTE)(bitStream>>8);
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out += 2;
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bitStream >>= 16;
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bitCount -= 16;
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}
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}
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/* flush remaining bitStream */
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if ((!safeWrite) && (out > oend - 2)) return (size_t)-FSE_ERROR_GENERIC; /* Buffer overflow */
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out[0] = (BYTE)bitStream;
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out[1] = (BYTE)(bitStream>>8);
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out+= (bitCount+7) /8;
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if (charnum > maxSymbolValue + 1) return (size_t)-FSE_ERROR_GENERIC; /* Too many symbols written (a bit too late?) */
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return (out-ostart);
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}
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#endif // __clang_analyzer__
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size_t FSE_writeNCount (void* header, size_t headerBufferSize, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog)
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{
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if (tableLog > FSE_MAX_TABLELOG) return (size_t)-FSE_ERROR_GENERIC; /* Unsupported */
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if (tableLog < FSE_MIN_TABLELOG) return (size_t)-FSE_ERROR_GENERIC; /* Unsupported */
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if (headerBufferSize < FSE_NCountWriteBound(maxSymbolValue, tableLog))
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return FSE_writeNCount_generic(header, headerBufferSize, normalizedCounter, maxSymbolValue, tableLog, 0);
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return FSE_writeNCount_generic(header, headerBufferSize, normalizedCounter, maxSymbolValue, tableLog, 1);
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}
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size_t FSE_readNCount (short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr,
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const void* headerBuffer, size_t hbSize)
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{
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const BYTE* const istart = (const BYTE*) headerBuffer;
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const BYTE* const iend = istart + hbSize;
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const BYTE* ip = istart;
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int nbBits;
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int remaining;
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int threshold;
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U32 bitStream;
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int bitCount;
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unsigned charnum = 0;
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int previous0 = 0;
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if (hbSize < 4) return (size_t)-FSE_ERROR_srcSize_wrong;
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bitStream = FSE_readLE32(ip);
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nbBits = (bitStream & 0xF) + FSE_MIN_TABLELOG; /* extract tableLog */
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if (nbBits > FSE_TABLELOG_ABSOLUTE_MAX) return (size_t)-FSE_ERROR_tableLog_tooLarge;
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bitStream >>= 4;
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bitCount = 4;
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*tableLogPtr = nbBits;
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remaining = (1<<nbBits)+1;
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threshold = 1<<nbBits;
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nbBits++;
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while ((remaining>1) && (charnum<=*maxSVPtr))
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{
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if (previous0)
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{
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unsigned n0 = charnum;
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while ((bitStream & 0xFFFF) == 0xFFFF)
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{
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n0+=24;
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ip+=2;
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bitStream = FSE_readLE32(ip) >> bitCount;
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}
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while ((bitStream & 3) == 3)
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{
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n0+=3;
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bitStream>>=2;
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bitCount+=2;
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}
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n0 += bitStream & 3;
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bitCount += 2;
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if (n0 > *maxSVPtr) return (size_t)-FSE_ERROR_maxSymbolValue_tooSmall;
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while (charnum < n0) normalizedCounter[charnum++] = 0;
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ip += bitCount>>3;
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bitCount &= 7;
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bitStream = FSE_readLE32(ip) >> bitCount;
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}
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{
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const short max = (short)((2*threshold-1)-remaining);
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short count;
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if ((bitStream & (threshold-1)) < (U32)max)
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{
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count = (short)(bitStream & (threshold-1));
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bitCount += nbBits-1;
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}
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else
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{
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count = (short)(bitStream & (2*threshold-1));
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if (count >= threshold) count -= max;
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bitCount += nbBits;
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}
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count--; /* extra accuracy */
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remaining -= FSE_abs(count);
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normalizedCounter[charnum++] = count;
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previous0 = !count;
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while (remaining < threshold)
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{
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nbBits--;
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threshold >>= 1;
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}
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{
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const BYTE* itarget = ip + (bitCount>>3);
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if (itarget > iend - 4)
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{
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ip = iend - 4;
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bitCount -= (int)(8 * (iend - 4 - ip));
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}
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else
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{
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ip = itarget;
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bitCount &= 7;
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}
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bitStream = FSE_readLE32(ip) >> (bitCount & 31);
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}
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}
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}
|
|
if (remaining != 1) return (size_t)-FSE_ERROR_GENERIC;
|
|
*maxSVPtr = charnum-1;
|
|
|
|
ip += (bitCount+7)>>3;
|
|
if ((size_t)(ip-istart) > hbSize) return (size_t)-FSE_ERROR_srcSize_wrong;
|
|
return ip-istart;
|
|
}
|
|
|
|
|
|
/****************************************************************
|
|
* FSE Compression Code
|
|
****************************************************************/
|
|
/*
|
|
FSE_CTable[0] 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, since C standard does not support variable-size structures.
|
|
*/
|
|
|
|
size_t FSE_sizeof_CTable (unsigned maxSymbolValue, unsigned tableLog)
|
|
{
|
|
size_t size;
|
|
FSE_STATIC_ASSERT((size_t)FSE_CTABLE_SIZE_U32(FSE_MAX_TABLELOG, FSE_MAX_SYMBOL_VALUE)*4 >= sizeof(CTable_max_t)); /* A compilation error here means FSE_CTABLE_SIZE_U32 is not large enough */
|
|
if (tableLog > FSE_MAX_TABLELOG) return (size_t)-FSE_ERROR_GENERIC;
|
|
size = FSE_CTABLE_SIZE_U32 (tableLog, maxSymbolValue) * sizeof(U32);
|
|
return size;
|
|
}
|
|
|
|
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*)malloc(size);
|
|
}
|
|
|
|
void FSE_freeCTable (FSE_CTable* ct)
|
|
{
|
|
free(ct);
|
|
}
|
|
|
|
|
|
unsigned FSE_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue)
|
|
{
|
|
U32 tableLog = maxTableLog;
|
|
if (tableLog==0) tableLog = FSE_DEFAULT_TABLELOG;
|
|
if ((FSE_highbit32((U32)(srcSize - 1)) - 2) < tableLog) tableLog = FSE_highbit32((U32)(srcSize - 1)) - 2; /* Accuracy can be reduced */
|
|
if ((FSE_highbit32(maxSymbolValue)+2) > tableLog) tableLog = FSE_highbit32(maxSymbolValue)+2; /* 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;
|
|
}
|
|
|
|
|
|
typedef struct
|
|
{
|
|
U32 id;
|
|
U32 count;
|
|
} rank_t;
|
|
|
|
int FSE_compareRankT(const void* r1, const void* r2)
|
|
{
|
|
const rank_t* R1 = (const rank_t*)r1;
|
|
const rank_t* R2 = (const rank_t*)r2;
|
|
|
|
return 2 * (R1->count < R2->count) - 1;
|
|
}
|
|
|
|
|
|
#if 0
|
|
static size_t FSE_adjustNormSlow(short* norm, int pointsToRemove, const unsigned* count, U32 maxSymbolValue)
|
|
{
|
|
rank_t rank[FSE_MAX_SYMBOL_VALUE+2];
|
|
U32 s;
|
|
|
|
/* Init */
|
|
for (s=0; s<=maxSymbolValue; s++)
|
|
{
|
|
rank[s].id = s;
|
|
rank[s].count = count[s];
|
|
if (norm[s] <= 1) rank[s].count = 0;
|
|
}
|
|
rank[maxSymbolValue+1].id = 0;
|
|
rank[maxSymbolValue+1].count = 0; /* ensures comparison ends here in worst case */
|
|
|
|
/* Sort according to count */
|
|
qsort(rank, maxSymbolValue+1, sizeof(rank_t), FSE_compareRankT);
|
|
|
|
while(pointsToRemove)
|
|
{
|
|
int newRank = 1;
|
|
rank_t savedR;
|
|
if (norm[rank[0].id] == 1)
|
|
return (size_t)-FSE_ERROR_GENERIC;
|
|
norm[rank[0].id]--;
|
|
pointsToRemove--;
|
|
rank[0].count -= (rank[0].count + 6) >> 3;
|
|
if (norm[rank[0].id] == 1)
|
|
rank[0].count=0;
|
|
savedR = rank[0];
|
|
while (rank[newRank].count > savedR.count)
|
|
{
|
|
rank[newRank-1] = rank[newRank];
|
|
newRank++;
|
|
}
|
|
rank[newRank-1] = savedR;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#else
|
|
|
|
/* 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)
|
|
{
|
|
U32 s;
|
|
U32 distributed = 0;
|
|
U32 ToDistribute;
|
|
|
|
/* Init */
|
|
U32 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]=-2;
|
|
}
|
|
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] == -2) && (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;
|
|
}
|
|
|
|
{
|
|
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)
|
|
{
|
|
U64 end = tmpTotal + (count[s] * rStep);
|
|
U32 sStart = (U32)(tmpTotal >> vStepLog);
|
|
U32 sEnd = (U32)(end >> vStepLog);
|
|
U32 weight = sEnd - sStart;
|
|
if (weight < 1)
|
|
return (size_t)-FSE_ERROR_GENERIC;
|
|
norm[s] = (short)weight;
|
|
tmpTotal = end;
|
|
}
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
|
|
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 (size_t)-FSE_ERROR_GENERIC; /* Unsupported size */
|
|
if (tableLog > FSE_MAX_TABLELOG) return (size_t)-FSE_ERROR_GENERIC; /* Unsupported size */
|
|
if ((1U<<tableLog) <= maxSymbolValue) return (size_t)-FSE_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 = ((U64)1<<62) / 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;
|
|
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 errorCode = FSE_normalizeM2(normalizedCounter, tableLog, count, total, maxSymbolValue);
|
|
if (FSE_isError(errorCode)) return errorCode;
|
|
}
|
|
else normalizedCounter[largest] += (short)stillToDistribute;
|
|
}
|
|
|
|
#if 0
|
|
{ /* Print Table (debug) */
|
|
U32 s;
|
|
U32 nTotal = 0;
|
|
for (s=0; s<=maxSymbolValue; s++)
|
|
printf("%3i: %4i \n", s, normalizedCounter[s]);
|
|
for (s=0; s<=maxSymbolValue; s++)
|
|
nTotal += abs(normalizedCounter[s]);
|
|
if (nTotal != (1U<<tableLog))
|
|
printf("Warning !!! Total == %u != %u !!!", nTotal, 1U<<tableLog);
|
|
getchar();
|
|
}
|
|
#endif
|
|
|
|
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;
|
|
U16* tableU16 = ( (U16*) ct) + 2;
|
|
FSE_symbolCompressionTransform* symbolTT = (FSE_symbolCompressionTransform*) ((((U32*)ct)+1) + (tableSize>>1));
|
|
unsigned s;
|
|
|
|
/* Sanity checks */
|
|
if (nbBits < 1) return (size_t)-FSE_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 */
|
|
for (s=0; s<=maxSymbolValue; s++)
|
|
{
|
|
symbolTT[s].minBitsOut = (BYTE)nbBits;
|
|
symbolTT[s].deltaFindState = s-1;
|
|
symbolTT[s].maxState = (U16)( (tableSize*2) - 1); /* ensures state <= maxState */
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* fake FSE_CTable, for rle (100% always same symbol) input */
|
|
size_t FSE_buildCTable_rle (FSE_CTable* ct, BYTE symbolValue)
|
|
{
|
|
const unsigned tableSize = 1;
|
|
U16* tableU16 = ( (U16*) ct) + 2;
|
|
FSE_symbolCompressionTransform* symbolTT = (FSE_symbolCompressionTransform*) ((U32*)ct + 2);
|
|
|
|
/* 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].minBitsOut = 0;
|
|
symbolTT[symbolValue].deltaFindState = 0;
|
|
symbolTT[symbolValue].maxState = (U16)(2*tableSize-1); /* ensures state <= maxState */
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
void FSE_initCStream(FSE_CStream_t* bitC, void* start)
|
|
{
|
|
bitC->bitContainer = 0;
|
|
bitC->bitPos = 0; /* reserved for unusedBits */
|
|
bitC->startPtr = (char*)start;
|
|
bitC->ptr = bitC->startPtr;
|
|
}
|
|
|
|
void FSE_initCState(FSE_CState_t* statePtr, const FSE_CTable* ct)
|
|
{
|
|
const U32 tableLog = ( (const U16*) ct) [0];
|
|
statePtr->value = (ptrdiff_t)1<<tableLog;
|
|
statePtr->stateTable = ((const U16*) ct) + 2;
|
|
statePtr->symbolTT = (const FSE_symbolCompressionTransform*)((const U32*)ct + 1 + (tableLog ? (1<<(tableLog-1)) : 1));
|
|
statePtr->stateLog = tableLog;
|
|
}
|
|
|
|
void FSE_addBits(FSE_CStream_t* bitC, size_t value, unsigned nbBits)
|
|
{
|
|
static const unsigned mask[] = { 0, 1, 3, 7, 0xF, 0x1F, 0x3F, 0x7F, 0xFF, 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF, 0x1FFFF, 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF, 0x7FFFFF, 0xFFFFFF, 0x1FFFFFF }; /* up to 25 bits */
|
|
bitC->bitContainer |= (value & mask[nbBits]) << bitC->bitPos;
|
|
bitC->bitPos += nbBits;
|
|
}
|
|
|
|
void FSE_encodeSymbol(FSE_CStream_t* bitC, FSE_CState_t* statePtr, BYTE symbol)
|
|
{
|
|
const FSE_symbolCompressionTransform symbolTT = ((const FSE_symbolCompressionTransform*)(statePtr->symbolTT))[symbol];
|
|
const U16* const stateTable = (const U16*)(statePtr->stateTable);
|
|
int nbBitsOut = symbolTT.minBitsOut;
|
|
nbBitsOut -= (int)((symbolTT.maxState - statePtr->value) >> 31);
|
|
FSE_addBits(bitC, statePtr->value, nbBitsOut);
|
|
statePtr->value = stateTable[ (statePtr->value >> nbBitsOut) + symbolTT.deltaFindState];
|
|
}
|
|
|
|
void FSE_flushBits(FSE_CStream_t* bitC)
|
|
{
|
|
size_t nbBytes = bitC->bitPos >> 3;
|
|
FSE_writeLEST(bitC->ptr, bitC->bitContainer);
|
|
bitC->bitPos &= 7;
|
|
bitC->ptr += nbBytes;
|
|
bitC->bitContainer >>= nbBytes*8;
|
|
}
|
|
|
|
void FSE_flushCState(FSE_CStream_t* bitC, const FSE_CState_t* statePtr)
|
|
{
|
|
FSE_addBits(bitC, statePtr->value, statePtr->stateLog);
|
|
FSE_flushBits(bitC);
|
|
}
|
|
|
|
|
|
size_t FSE_closeCStream(FSE_CStream_t* bitC)
|
|
{
|
|
char* endPtr;
|
|
|
|
FSE_addBits(bitC, 1, 1);
|
|
FSE_flushBits(bitC);
|
|
|
|
endPtr = bitC->ptr;
|
|
endPtr += bitC->bitPos > 0;
|
|
|
|
return (endPtr - bitC->startPtr);
|
|
}
|
|
|
|
|
|
size_t FSE_compress_usingCTable (void* dst, size_t dstSize,
|
|
const void* src, size_t srcSize,
|
|
const FSE_CTable* ct)
|
|
{
|
|
const BYTE* const istart = (const BYTE*) src;
|
|
const BYTE* ip;
|
|
const BYTE* const iend = istart + srcSize;
|
|
|
|
FSE_CStream_t bitC;
|
|
FSE_CState_t CState1, CState2;
|
|
|
|
|
|
/* init */
|
|
(void)dstSize; /* objective : ensure it fits into dstBuffer (Todo) */
|
|
FSE_initCStream(&bitC, dst);
|
|
FSE_initCState(&CState1, ct);
|
|
CState2 = CState1;
|
|
|
|
ip=iend;
|
|
|
|
/* join to even */
|
|
if (srcSize & 1)
|
|
{
|
|
FSE_encodeSymbol(&bitC, &CState1, *--ip);
|
|
FSE_flushBits(&bitC);
|
|
}
|
|
|
|
/* join to mod 4 */
|
|
if ((sizeof(size_t)*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(size_t)*8 < FSE_MAX_TABLELOG*2+7 ) /* this test must be static */
|
|
FSE_flushBits(&bitC);
|
|
|
|
FSE_encodeSymbol(&bitC, &CState1, *--ip);
|
|
|
|
if (sizeof(size_t)*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 FSE_closeCStream(&bitC);
|
|
}
|
|
|
|
|
|
size_t FSE_compressBound(size_t size) { return FSE_COMPRESSBOUND(size); }
|
|
|
|
|
|
size_t FSE_compress2 (void* dst, size_t dstSize, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog)
|
|
{
|
|
const BYTE* const istart = (const BYTE*) src;
|
|
const BYTE* ip = istart;
|
|
|
|
BYTE* const ostart = (BYTE*) dst;
|
|
BYTE* op = ostart;
|
|
BYTE* const oend = ostart + dstSize;
|
|
|
|
U32 count[FSE_MAX_SYMBOL_VALUE+1];
|
|
S16 norm[FSE_MAX_SYMBOL_VALUE+1];
|
|
CTable_max_t ct;
|
|
size_t errorCode;
|
|
|
|
/* early out */
|
|
if (dstSize < FSE_compressBound(srcSize)) return (size_t)-FSE_ERROR_dstSize_tooSmall;
|
|
if (srcSize <= 1) return srcSize; /* Uncompressed or RLE */
|
|
if (!maxSymbolValue) maxSymbolValue = FSE_MAX_SYMBOL_VALUE;
|
|
if (!tableLog) tableLog = FSE_DEFAULT_TABLELOG;
|
|
|
|
/* Scan input and build symbol stats */
|
|
errorCode = FSE_count (count, &maxSymbolValue, ip, srcSize);
|
|
if (FSE_isError(errorCode)) return errorCode;
|
|
if (errorCode == srcSize) return 1;
|
|
if (errorCode < (srcSize >> 7)) return 0; /* Heuristic : not compressible enough */
|
|
|
|
tableLog = FSE_optimalTableLog(tableLog, srcSize, maxSymbolValue);
|
|
errorCode = FSE_normalizeCount (norm, tableLog, count, srcSize, maxSymbolValue);
|
|
if (FSE_isError(errorCode)) return errorCode;
|
|
|
|
/* Write table description header */
|
|
errorCode = FSE_writeNCount (op, FSE_MAX_HEADERSIZE, norm, maxSymbolValue, tableLog);
|
|
if (FSE_isError(errorCode)) return errorCode;
|
|
op += errorCode;
|
|
|
|
/* Compress */
|
|
errorCode = FSE_buildCTable (ct, norm, maxSymbolValue, tableLog);
|
|
if (FSE_isError(errorCode)) return errorCode;
|
|
op += FSE_compress_usingCTable(op, oend - op, ip, srcSize, ct);
|
|
|
|
/* check compressibility */
|
|
if ( (size_t)(op-ostart) >= srcSize-1 )
|
|
return 0;
|
|
|
|
return op-ostart;
|
|
}
|
|
|
|
|
|
size_t FSE_compress (void* dst, size_t dstSize, const void* src, size_t srcSize)
|
|
{
|
|
return FSE_compress2(dst, dstSize, src, (U32)srcSize, FSE_MAX_SYMBOL_VALUE, FSE_DEFAULT_TABLELOG);
|
|
}
|
|
|
|
|
|
/*********************************************************
|
|
* Decompression (Byte symbols)
|
|
*********************************************************/
|
|
typedef struct
|
|
{
|
|
U16 newState;
|
|
BYTE symbol;
|
|
BYTE nbBits;
|
|
} FSE_decode_t; /* size == U32 */
|
|
|
|
|
|
size_t FSE_buildDTable_rle (FSE_DTable* dt, BYTE symbolValue)
|
|
{
|
|
U32* const base32 = (U32*)dt;
|
|
FSE_decode_t* const cell = (FSE_decode_t*)(base32 + 1);
|
|
|
|
base32[0] = 0;
|
|
|
|
cell->newState = 0;
|
|
cell->symbol = symbolValue;
|
|
cell->nbBits = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
size_t FSE_buildDTable_raw (FSE_DTable* dt, unsigned nbBits)
|
|
{
|
|
U32* const base32 = (U32*)dt;
|
|
FSE_decode_t* dinfo = (FSE_decode_t*)(base32 + 1);
|
|
const unsigned tableSize = 1 << nbBits;
|
|
const unsigned tableMask = tableSize - 1;
|
|
const unsigned maxSymbolValue = tableMask;
|
|
unsigned s;
|
|
|
|
/* Sanity checks */
|
|
if (nbBits < 1) return (size_t)-FSE_ERROR_GENERIC; /* min size */
|
|
|
|
/* Build Decoding Table */
|
|
base32[0] = nbBits;
|
|
for (s=0; s<=maxSymbolValue; s++)
|
|
{
|
|
dinfo[s].newState = 0;
|
|
dinfo[s].symbol = (BYTE)s;
|
|
dinfo[s].nbBits = (BYTE)nbBits;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* FSE_initDStream
|
|
* Initialize a FSE_DStream_t.
|
|
* srcBuffer must point at the beginning of an FSE block.
|
|
* The function result is the size of the FSE_block (== srcSize).
|
|
* If srcSize is too small, the function will return an errorCode;
|
|
*/
|
|
size_t FSE_initDStream(FSE_DStream_t* bitD, const void* srcBuffer, size_t srcSize)
|
|
{
|
|
if (srcSize < 1) return (size_t)-FSE_ERROR_srcSize_wrong;
|
|
|
|
if (srcSize >= sizeof(size_t))
|
|
{
|
|
U32 contain32;
|
|
bitD->start = (const char*)srcBuffer;
|
|
bitD->ptr = (const char*)srcBuffer + srcSize - sizeof(size_t);
|
|
bitD->bitContainer = FSE_readLEST(bitD->ptr);
|
|
contain32 = ((const BYTE*)srcBuffer)[srcSize-1];
|
|
if (contain32 == 0) return (size_t)-FSE_ERROR_GENERIC; /* stop bit not present */
|
|
bitD->bitsConsumed = 8 - FSE_highbit32(contain32);
|
|
}
|
|
else
|
|
{
|
|
U32 contain32;
|
|
bitD->start = (const char*)srcBuffer;
|
|
bitD->ptr = bitD->start;
|
|
bitD->bitContainer = *(const BYTE*)(bitD->start);
|
|
switch(srcSize)
|
|
{
|
|
case 7: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[6]) << (sizeof(size_t)*8 - 16);
|
|
case 6: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[5]) << (sizeof(size_t)*8 - 24);
|
|
case 5: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[4]) << (sizeof(size_t)*8 - 32);
|
|
case 4: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[3]) << 24;
|
|
case 3: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[2]) << 16;
|
|
case 2: bitD->bitContainer += (size_t)(((const BYTE*)(bitD->start))[1]) << 8;
|
|
default:;
|
|
}
|
|
contain32 = ((const BYTE*)srcBuffer)[srcSize-1];
|
|
if (contain32 == 0) return (size_t)-FSE_ERROR_GENERIC; /* stop bit not present */
|
|
bitD->bitsConsumed = 8 - FSE_highbit32(contain32);
|
|
bitD->bitsConsumed += (U32)(sizeof(size_t) - srcSize)*8;
|
|
}
|
|
|
|
return srcSize;
|
|
}
|
|
|
|
|
|
/* FSE_readBits
|
|
* Read next n bits from the bitContainer.
|
|
* On 32-bits, don't read more than maxNbBits==25
|
|
* On 64-bits, don't read more than maxNbBits==57
|
|
* Use the fast variant *only* if n >= 1.
|
|
* return : value extracted.
|
|
*/
|
|
size_t FSE_readBits(FSE_DStream_t* bitD, U32 nbBits)
|
|
{
|
|
size_t value = ((bitD->bitContainer << (bitD->bitsConsumed & ((sizeof(size_t)*8)-1))) >> 1) >> (((sizeof(size_t)*8)-1)-nbBits);
|
|
bitD->bitsConsumed += nbBits;
|
|
return value;
|
|
}
|
|
|
|
size_t FSE_readBitsFast(FSE_DStream_t* bitD, U32 nbBits) /* only if nbBits >= 1 !! */
|
|
{
|
|
size_t value = (bitD->bitContainer << bitD->bitsConsumed) >> ((sizeof(size_t)*8)-nbBits);
|
|
bitD->bitsConsumed += nbBits;
|
|
return value;
|
|
}
|
|
|
|
unsigned FSE_reloadDStream(FSE_DStream_t* bitD)
|
|
{
|
|
if (bitD->ptr >= bitD->start + sizeof(size_t))
|
|
{
|
|
bitD->ptr -= bitD->bitsConsumed >> 3;
|
|
bitD->bitsConsumed &= 7;
|
|
bitD->bitContainer = FSE_readLEST(bitD->ptr);
|
|
return 0;
|
|
}
|
|
if (bitD->ptr == bitD->start)
|
|
{
|
|
if (bitD->bitsConsumed < sizeof(size_t)*8) return 1;
|
|
if (bitD->bitsConsumed == sizeof(size_t)*8) return 2;
|
|
return 3;
|
|
}
|
|
{
|
|
U32 nbBytes = bitD->bitsConsumed >> 3;
|
|
if (bitD->ptr - nbBytes < bitD->start)
|
|
nbBytes = (U32)(bitD->ptr - bitD->start); /* note : necessarily ptr > start */
|
|
bitD->ptr -= nbBytes;
|
|
bitD->bitsConsumed -= nbBytes*8;
|
|
bitD->bitContainer = FSE_readLEST(bitD->ptr); /* note : necessarily srcSize > sizeof(bitD) */
|
|
return (bitD->ptr == bitD->start);
|
|
}
|
|
}
|
|
|
|
|
|
void FSE_initDState(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD, const FSE_DTable* dt)
|
|
{
|
|
const U32* const base32 = (const U32*)dt;
|
|
DStatePtr->state = FSE_readBits(bitD, base32[0]);
|
|
FSE_reloadDStream(bitD);
|
|
DStatePtr->table = base32 + 1;
|
|
}
|
|
|
|
BYTE FSE_decodeSymbol(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD)
|
|
{
|
|
const FSE_decode_t DInfo = ((const FSE_decode_t*)(DStatePtr->table))[DStatePtr->state];
|
|
const U32 nbBits = DInfo.nbBits;
|
|
BYTE symbol = DInfo.symbol;
|
|
size_t lowBits = FSE_readBits(bitD, nbBits);
|
|
|
|
DStatePtr->state = DInfo.newState + lowBits;
|
|
return symbol;
|
|
}
|
|
|
|
BYTE FSE_decodeSymbolFast(FSE_DState_t* DStatePtr, FSE_DStream_t* bitD)
|
|
{
|
|
const FSE_decode_t DInfo = ((const FSE_decode_t*)(DStatePtr->table))[DStatePtr->state];
|
|
const U32 nbBits = DInfo.nbBits;
|
|
BYTE symbol = DInfo.symbol;
|
|
size_t lowBits = FSE_readBitsFast(bitD, nbBits);
|
|
|
|
DStatePtr->state = DInfo.newState + lowBits;
|
|
return symbol;
|
|
}
|
|
|
|
/* FSE_endOfDStream
|
|
Tells if bitD has reached end of bitStream or not */
|
|
|
|
unsigned FSE_endOfDStream(const FSE_DStream_t* bitD)
|
|
{
|
|
return ((bitD->ptr == bitD->start) && (bitD->bitsConsumed == sizeof(size_t)*8));
|
|
}
|
|
|
|
unsigned FSE_endOfDState(const FSE_DState_t* DStatePtr)
|
|
{
|
|
return DStatePtr->state == 0;
|
|
}
|
|
|
|
|
|
FORCE_INLINE size_t FSE_decompress_usingDTable_generic(
|
|
void* dst, size_t maxDstSize,
|
|
const void* cSrc, size_t cSrcSize,
|
|
const FSE_DTable* dt, unsigned fast)
|
|
{
|
|
BYTE* const ostart = (BYTE*) dst;
|
|
BYTE* op = ostart;
|
|
BYTE* const omax = op + maxDstSize;
|
|
BYTE* const olimit = omax-3;
|
|
|
|
FSE_DStream_t bitD;
|
|
FSE_DState_t state1;
|
|
FSE_DState_t state2;
|
|
size_t errorCode;
|
|
|
|
/* Init */
|
|
errorCode = FSE_initDStream(&bitD, cSrc, cSrcSize); /* replaced last arg by maxCompressed Size */
|
|
if (FSE_isError(errorCode)) return errorCode;
|
|
|
|
FSE_initDState(&state1, &bitD, dt);
|
|
FSE_initDState(&state2, &bitD, dt);
|
|
|
|
|
|
/* 2 symbols per loop */
|
|
while (!FSE_reloadDStream(&bitD) && (op<olimit))
|
|
{
|
|
*op++ = fast ? FSE_decodeSymbolFast(&state1, &bitD) : FSE_decodeSymbol(&state1, &bitD);
|
|
|
|
if (FSE_MAX_TABLELOG*2+7 > sizeof(size_t)*8) /* This test must be static */
|
|
FSE_reloadDStream(&bitD);
|
|
|
|
*op++ = fast ? FSE_decodeSymbolFast(&state2, &bitD) : FSE_decodeSymbol(&state2, &bitD);
|
|
|
|
if (FSE_MAX_TABLELOG*4+7 < sizeof(size_t)*8) /* This test must be static */
|
|
{
|
|
*op++ = fast ? FSE_decodeSymbolFast(&state1, &bitD) : FSE_decodeSymbol(&state1, &bitD);
|
|
*op++ = fast ? FSE_decodeSymbolFast(&state2, &bitD) : FSE_decodeSymbol(&state2, &bitD);
|
|
}
|
|
}
|
|
|
|
/* tail */
|
|
/* note : FSE_reloadDStream(&bitD) >= 1; Ends at exactly 2 */
|
|
while (1)
|
|
{
|
|
if ( (FSE_reloadDStream(&bitD)>2) || (op==omax) || (FSE_endOfDStream(&bitD) && (fast || FSE_endOfDState(&state1))) )
|
|
break;
|
|
|
|
*op++ = fast ? FSE_decodeSymbolFast(&state1, &bitD) : FSE_decodeSymbol(&state1, &bitD);
|
|
|
|
if ( (FSE_reloadDStream(&bitD)>2) || (op==omax) || (FSE_endOfDStream(&bitD) && (fast || FSE_endOfDState(&state2))) )
|
|
break;
|
|
|
|
*op++ = fast ? FSE_decodeSymbolFast(&state2, &bitD) : FSE_decodeSymbol(&state2, &bitD);
|
|
}
|
|
|
|
/* end ? */
|
|
if (FSE_endOfDStream(&bitD) && FSE_endOfDState(&state1) && FSE_endOfDState(&state2) )
|
|
return op-ostart;
|
|
|
|
if (op==omax) return (size_t)-FSE_ERROR_dstSize_tooSmall; /* dst buffer is full, but cSrc unfinished */
|
|
|
|
return (size_t)-FSE_ERROR_corruptionDetected;
|
|
}
|
|
|
|
|
|
size_t FSE_decompress_usingDTable(void* dst, size_t originalSize,
|
|
const void* cSrc, size_t cSrcSize,
|
|
const FSE_DTable* dt, size_t fastMode)
|
|
{
|
|
/* select fast mode (static) */
|
|
if (fastMode) return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 1);
|
|
return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 0);
|
|
}
|
|
|
|
|
|
size_t FSE_decompress(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize)
|
|
{
|
|
const BYTE* const istart = (const BYTE*)cSrc;
|
|
const BYTE* ip = istart;
|
|
short counting[FSE_MAX_SYMBOL_VALUE+1];
|
|
DTable_max_t dt; /* Static analyzer seems unable to understand this table will be properly initialized later */
|
|
unsigned tableLog;
|
|
unsigned maxSymbolValue = FSE_MAX_SYMBOL_VALUE;
|
|
size_t errorCode, fastMode;
|
|
|
|
if (cSrcSize<2) return (size_t)-FSE_ERROR_srcSize_wrong; /* too small input size */
|
|
|
|
/* normal FSE decoding mode */
|
|
errorCode = FSE_readNCount (counting, &maxSymbolValue, &tableLog, istart, cSrcSize);
|
|
if (FSE_isError(errorCode)) return errorCode;
|
|
if (errorCode >= cSrcSize) return (size_t)-FSE_ERROR_srcSize_wrong; /* too small input size */
|
|
ip += errorCode;
|
|
cSrcSize -= errorCode;
|
|
|
|
fastMode = FSE_buildDTable (dt, counting, maxSymbolValue, tableLog);
|
|
if (FSE_isError(fastMode)) return fastMode;
|
|
|
|
/* always return, even if it is an error code */
|
|
return FSE_decompress_usingDTable (dst, maxDstSize, ip, cSrcSize, dt, fastMode);
|
|
}
|
|
|
|
|
|
#endif /* FSE_COMMONDEFS_ONLY */
|
|
|
|
/*
|
|
2nd part of the file
|
|
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 */
|
|
size_t FSE_FUNCTION_NAME(FSE_count_generic, FSE_FUNCTION_EXTENSION)
|
|
(unsigned* count, unsigned* maxSymbolValuePtr, const FSE_FUNCTION_TYPE* source, size_t sourceSize, unsigned safe)
|
|
{
|
|
const FSE_FUNCTION_TYPE* ip = source;
|
|
const FSE_FUNCTION_TYPE* const iend = ip+sourceSize;
|
|
unsigned maxSymbolValue = *maxSymbolValuePtr;
|
|
unsigned max=0;
|
|
int s;
|
|
|
|
U32 Counting1[FSE_MAX_SYMBOL_VALUE+1] = { 0 };
|
|
U32 Counting2[FSE_MAX_SYMBOL_VALUE+1] = { 0 };
|
|
U32 Counting3[FSE_MAX_SYMBOL_VALUE+1] = { 0 };
|
|
U32 Counting4[FSE_MAX_SYMBOL_VALUE+1] = { 0 };
|
|
|
|
/* safety checks */
|
|
if (!sourceSize)
|
|
{
|
|
memset(count, 0, (maxSymbolValue + 1) * sizeof(FSE_FUNCTION_TYPE));
|
|
*maxSymbolValuePtr = 0;
|
|
return 0;
|
|
}
|
|
if (maxSymbolValue > FSE_MAX_SYMBOL_VALUE) return (size_t)-FSE_ERROR_GENERIC; /* maxSymbolValue too large : unsupported */
|
|
if (!maxSymbolValue) maxSymbolValue = FSE_MAX_SYMBOL_VALUE; /* 0 == default */
|
|
|
|
if ((safe) || (sizeof(FSE_FUNCTION_TYPE)>1))
|
|
{
|
|
/* check input values, to avoid count table overflow */
|
|
while (ip < iend-3)
|
|
{
|
|
if (*ip>maxSymbolValue) return (size_t)-FSE_ERROR_GENERIC; Counting1[*ip++]++;
|
|
if (*ip>maxSymbolValue) return (size_t)-FSE_ERROR_GENERIC; Counting2[*ip++]++;
|
|
if (*ip>maxSymbolValue) return (size_t)-FSE_ERROR_GENERIC; Counting3[*ip++]++;
|
|
if (*ip>maxSymbolValue) return (size_t)-FSE_ERROR_GENERIC; Counting4[*ip++]++;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
U32 cached = FSE_read32(ip); ip += 4;
|
|
while (ip < iend-15)
|
|
{
|
|
U32 c = cached; cached = FSE_read32(ip); ip += 4;
|
|
Counting1[(BYTE) c ]++;
|
|
Counting2[(BYTE)(c>>8) ]++;
|
|
Counting3[(BYTE)(c>>16)]++;
|
|
Counting4[ c>>24 ]++;
|
|
c = cached; cached = FSE_read32(ip); ip += 4;
|
|
Counting1[(BYTE) c ]++;
|
|
Counting2[(BYTE)(c>>8) ]++;
|
|
Counting3[(BYTE)(c>>16)]++;
|
|
Counting4[ c>>24 ]++;
|
|
c = cached; cached = FSE_read32(ip); ip += 4;
|
|
Counting1[(BYTE) c ]++;
|
|
Counting2[(BYTE)(c>>8) ]++;
|
|
Counting3[(BYTE)(c>>16)]++;
|
|
Counting4[ c>>24 ]++;
|
|
c = cached; cached = FSE_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) { if ((safe) && (*ip>maxSymbolValue)) return (size_t)-FSE_ERROR_GENERIC; Counting1[*ip++]++; }
|
|
|
|
for (s=0; s<=(int)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;
|
|
}
|
|
|
|
/* hidden fast variant (unsafe) */
|
|
size_t FSE_FUNCTION_NAME(FSE_countFast, FSE_FUNCTION_EXTENSION)
|
|
(unsigned* count, unsigned* maxSymbolValuePtr, const FSE_FUNCTION_TYPE* source, size_t sourceSize)
|
|
{
|
|
return FSE_FUNCTION_NAME(FSE_count_generic, FSE_FUNCTION_EXTENSION) (count, maxSymbolValuePtr, source, sourceSize, 0);
|
|
}
|
|
|
|
size_t FSE_FUNCTION_NAME(FSE_count, FSE_FUNCTION_EXTENSION)
|
|
(unsigned* count, unsigned* maxSymbolValuePtr, const FSE_FUNCTION_TYPE* source, size_t sourceSize)
|
|
{
|
|
if ((sizeof(FSE_FUNCTION_TYPE)==1) && (*maxSymbolValuePtr >= 255))
|
|
{
|
|
*maxSymbolValuePtr = 255;
|
|
return FSE_FUNCTION_NAME(FSE_count_generic, FSE_FUNCTION_EXTENSION) (count, maxSymbolValuePtr, source, sourceSize, 0);
|
|
}
|
|
return FSE_FUNCTION_NAME(FSE_count_generic, FSE_FUNCTION_EXTENSION) (count, maxSymbolValuePtr, source, sourceSize, 1);
|
|
}
|
|
|
|
|
|
static U32 FSE_tableStep(U32 tableSize) { return (tableSize>>1) + (tableSize>>3) + 3; }
|
|
|
|
size_t FSE_FUNCTION_NAME(FSE_buildCTable, FSE_FUNCTION_EXTENSION)
|
|
(FSE_CTable* ct, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog)
|
|
{
|
|
const unsigned tableSize = 1 << tableLog;
|
|
const unsigned tableMask = tableSize - 1;
|
|
U16* tableU16 = ( (U16*) ct) + 2;
|
|
FSE_symbolCompressionTransform* symbolTT = (FSE_symbolCompressionTransform*) (((U32*)ct) + 1 + (tableLog ? tableSize>>1 : 1) );
|
|
const unsigned step = FSE_tableStep(tableSize);
|
|
unsigned cumul[FSE_MAX_SYMBOL_VALUE+2];
|
|
U32 position = 0;
|
|
FSE_FUNCTION_TYPE tableSymbol[FSE_MAX_TABLESIZE] = {0}; /* should not be necessary, but analyzer complain without it, and performance loss is negligible with it */
|
|
U32 highThreshold = tableSize-1;
|
|
unsigned symbol;
|
|
unsigned i;
|
|
|
|
/* 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 */
|
|
cumul[0] = 0;
|
|
for (i=1; i<=maxSymbolValue+1; i++)
|
|
{
|
|
if (normalizedCounter[i-1]==-1) /* Low prob symbol */
|
|
{
|
|
cumul[i] = cumul[i-1] + 1;
|
|
tableSymbol[highThreshold--] = (FSE_FUNCTION_TYPE)(i-1);
|
|
}
|
|
else
|
|
cumul[i] = cumul[i-1] + normalizedCounter[i-1];
|
|
}
|
|
cumul[maxSymbolValue+1] = tableSize+1;
|
|
|
|
/* Spread symbols */
|
|
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; /* Lowprob area */
|
|
}
|
|
}
|
|
|
|
if (position!=0) return (size_t)-FSE_ERROR_GENERIC; /* Must have gone through all positions */
|
|
|
|
/* Build table */
|
|
for (i=0; i<tableSize; i++)
|
|
{
|
|
FSE_FUNCTION_TYPE s = tableSymbol[i];
|
|
tableU16[cumul[s]++] = (U16) (tableSize+i); /* Table U16 : sorted by symbol order; gives next state value */
|
|
}
|
|
|
|
/* Build Symbol Transformation Table */
|
|
{
|
|
unsigned s;
|
|
unsigned total = 0;
|
|
for (s=0; s<=maxSymbolValue; s++)
|
|
{
|
|
switch (normalizedCounter[s])
|
|
{
|
|
case 0:
|
|
break;
|
|
case -1:
|
|
case 1:
|
|
symbolTT[s].minBitsOut = (BYTE)tableLog;
|
|
symbolTT[s].deltaFindState = total - 1;
|
|
total ++;
|
|
symbolTT[s].maxState = (U16)( (tableSize*2) - 1); /* ensures state <= maxState */
|
|
break;
|
|
default :
|
|
symbolTT[s].minBitsOut = (BYTE)( (tableLog-1) - FSE_highbit32 (normalizedCounter[s]-1) );
|
|
symbolTT[s].deltaFindState = total - normalizedCounter[s];
|
|
total += normalizedCounter[s];
|
|
symbolTT[s].maxState = (U16)( (normalizedCounter[s] << (symbolTT[s].minBitsOut+1)) - 1);
|
|
}
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
#define FSE_DECODE_TYPE FSE_TYPE_NAME(FSE_decode_t, FSE_FUNCTION_EXTENSION)
|
|
|
|
FSE_DTable* FSE_FUNCTION_NAME(FSE_createDTable, FSE_FUNCTION_EXTENSION) (unsigned tableLog)
|
|
{
|
|
if (tableLog > FSE_TABLELOG_ABSOLUTE_MAX) tableLog = FSE_TABLELOG_ABSOLUTE_MAX;
|
|
return (FSE_DTable*)malloc( FSE_DTABLE_SIZE_U32(tableLog) * sizeof (U32) );
|
|
}
|
|
|
|
void FSE_FUNCTION_NAME(FSE_freeDTable, FSE_FUNCTION_EXTENSION) (FSE_DTable* dt)
|
|
{
|
|
free(dt);
|
|
}
|
|
|
|
|
|
size_t FSE_FUNCTION_NAME(FSE_buildDTable, FSE_FUNCTION_EXTENSION)
|
|
(FSE_DTable* dt, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog)
|
|
{
|
|
U32* const base32 = (U32*)dt;
|
|
FSE_DECODE_TYPE* const tableDecode = (FSE_DECODE_TYPE*) (base32+1);
|
|
const U32 tableSize = 1 << tableLog;
|
|
const U32 tableMask = tableSize-1;
|
|
const U32 step = FSE_tableStep(tableSize);
|
|
U16 symbolNext[FSE_MAX_SYMBOL_VALUE+1];
|
|
U32 position = 0;
|
|
U32 highThreshold = tableSize-1;
|
|
const S16 largeLimit= (S16)(1 << (tableLog-1));
|
|
U32 noLarge = 1;
|
|
U32 s;
|
|
|
|
/* Sanity Checks */
|
|
if (maxSymbolValue > FSE_MAX_SYMBOL_VALUE) return (size_t)-FSE_ERROR_maxSymbolValue_tooLarge;
|
|
if (tableLog > FSE_MAX_TABLELOG) return (size_t)-FSE_ERROR_tableLog_tooLarge;
|
|
|
|
/* Init, lay down lowprob symbols */
|
|
base32[0] = tableLog;
|
|
for (s=0; s<=maxSymbolValue; s++)
|
|
{
|
|
if (normalizedCounter[s]==-1)
|
|
{
|
|
tableDecode[highThreshold--].symbol = (FSE_FUNCTION_TYPE)s;
|
|
symbolNext[s] = 1;
|
|
}
|
|
else
|
|
{
|
|
if (normalizedCounter[s] >= largeLimit) noLarge=0;
|
|
symbolNext[s] = normalizedCounter[s];
|
|
}
|
|
}
|
|
|
|
/* Spread symbols */
|
|
for (s=0; s<=maxSymbolValue; s++)
|
|
{
|
|
int i;
|
|
for (i=0; i<normalizedCounter[s]; i++)
|
|
{
|
|
tableDecode[position].symbol = (FSE_FUNCTION_TYPE)s;
|
|
position = (position + step) & tableMask;
|
|
while (position > highThreshold) position = (position + step) & tableMask; /* lowprob area */
|
|
}
|
|
}
|
|
|
|
if (position!=0) return (size_t)-FSE_ERROR_GENERIC; /* position must reach all cells once, otherwise normalizedCounter is incorrect */
|
|
|
|
/* Build Decoding table */
|
|
{
|
|
U32 i;
|
|
for (i=0; i<tableSize; i++)
|
|
{
|
|
FSE_FUNCTION_TYPE symbol = (FSE_FUNCTION_TYPE)(tableDecode[i].symbol);
|
|
U16 nextState = symbolNext[symbol]++;
|
|
tableDecode[i].nbBits = (BYTE) (tableLog - FSE_highbit32 ((U32)nextState) );
|
|
tableDecode[i].newState = (U16) ( (nextState << tableDecode[i].nbBits) - tableSize);
|
|
}
|
|
}
|
|
|
|
return noLarge;
|
|
}
|