[pcsx_rearmed.git] / deps / libchdr / deps / zstd-1.5.5 / lib / common / huf.h

/* ******************************************************************
 * huff0 huffman codec,
 * part of Finite State Entropy library
 * Copyright (c) Meta Platforms, Inc. and affiliates.
 *
 * You can contact the author at :
 * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
 *
 * 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.
****************************************************************** */

#if defined (__cplusplus)
extern "C" {
#endif

#ifndef HUF_H_298734234
#define HUF_H_298734234

/* *** Dependencies *** */
#include "zstd_deps.h"    /* size_t */
#include "mem.h"          /* U32 */
#define FSE_STATIC_LINKING_ONLY
#include "fse.h"


/* ***   Tool functions *** */
#define HUF_BLOCKSIZE_MAX (128 * 1024)   /**< maximum input size for a single block compressed with HUF_compress */
size_t HUF_compressBound(size_t size);   /**< maximum compressed size (worst case) */

/* Error Management */
unsigned    HUF_isError(size_t code);       /**< tells if a return value is an error code */
const char* HUF_getErrorName(size_t code);  /**< provides error code string (useful for debugging) */


#define HUF_WORKSPACE_SIZE ((8 << 10) + 512 /* sorting scratch space */)
#define HUF_WORKSPACE_SIZE_U64 (HUF_WORKSPACE_SIZE / sizeof(U64))

/* *** Constants *** */
#define HUF_TABLELOG_MAX      12      /* max runtime value of tableLog (due to static allocation); can be modified up to HUF_TABLELOG_ABSOLUTEMAX */
#define HUF_TABLELOG_DEFAULT  11      /* default tableLog value when none specified */
#define HUF_SYMBOLVALUE_MAX  255

#define HUF_TABLELOG_ABSOLUTEMAX  12  /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */
#if (HUF_TABLELOG_MAX > HUF_TABLELOG_ABSOLUTEMAX)
#  error "HUF_TABLELOG_MAX is too large !"
#endif


/* ****************************************
*  Static allocation
******************************************/
/* HUF buffer bounds */
#define HUF_CTABLEBOUND 129
#define HUF_BLOCKBOUND(size) (size + (size>>8) + 8)   /* only true when incompressible is pre-filtered with fast heuristic */
#define HUF_COMPRESSBOUND(size) (HUF_CTABLEBOUND + HUF_BLOCKBOUND(size))   /* Macro version, useful for static allocation */

/* static allocation of HUF's Compression Table */
/* this is a private definition, just exposed for allocation and strict aliasing purpose. never EVER access its members directly */
typedef size_t HUF_CElt;   /* consider it an incomplete type */
#define HUF_CTABLE_SIZE_ST(maxSymbolValue)   ((maxSymbolValue)+2)   /* Use tables of size_t, for proper alignment */
#define HUF_CTABLE_SIZE(maxSymbolValue)       (HUF_CTABLE_SIZE_ST(maxSymbolValue) * sizeof(size_t))
#define HUF_CREATE_STATIC_CTABLE(name, maxSymbolValue) \
    HUF_CElt name[HUF_CTABLE_SIZE_ST(maxSymbolValue)] /* no final ; */

/* static allocation of HUF's DTable */
typedef U32 HUF_DTable;
#define HUF_DTABLE_SIZE(maxTableLog)   (1 + (1<<(maxTableLog)))
#define HUF_CREATE_STATIC_DTABLEX1(DTable, maxTableLog) \
        HUF_DTable DTable[HUF_DTABLE_SIZE((maxTableLog)-1)] = { ((U32)((maxTableLog)-1) * 0x01000001) }
#define HUF_CREATE_STATIC_DTABLEX2(DTable, maxTableLog) \
        HUF_DTable DTable[HUF_DTABLE_SIZE(maxTableLog)] = { ((U32)(maxTableLog) * 0x01000001) }


/* ****************************************
*  Advanced decompression functions
******************************************/

/**
 * Huffman flags bitset.
 * For all flags, 0 is the default value.
 */
typedef enum {
    /**
     * If compiled with DYNAMIC_BMI2: Set flag only if the CPU supports BMI2 at runtime.
     * Otherwise: Ignored.
     */
    HUF_flags_bmi2 = (1 << 0),
    /**
     * If set: Test possible table depths to find the one that produces the smallest header + encoded size.
     * If unset: Use heuristic to find the table depth.
     */
    HUF_flags_optimalDepth = (1 << 1),
    /**
     * If set: If the previous table can encode the input, always reuse the previous table.
     * If unset: If the previous table can encode the input, reuse the previous table if it results in a smaller output.
     */
    HUF_flags_preferRepeat = (1 << 2),
    /**
     * If set: Sample the input and check if the sample is uncompressible, if it is then don't attempt to compress.
     * If unset: Always histogram the entire input.
     */
    HUF_flags_suspectUncompressible = (1 << 3),
    /**
     * If set: Don't use assembly implementations
     * If unset: Allow using assembly implementations
     */
    HUF_flags_disableAsm = (1 << 4),
    /**
     * If set: Don't use the fast decoding loop, always use the fallback decoding loop.
     * If unset: Use the fast decoding loop when possible.
     */
    HUF_flags_disableFast = (1 << 5)
} HUF_flags_e;


/* ****************************************
 *  HUF detailed API
 * ****************************************/
#define HUF_OPTIMAL_DEPTH_THRESHOLD ZSTD_btultra

/*! HUF_compress() does the following:
 *  1. count symbol occurrence from source[] into table count[] using FSE_count() (exposed within "fse.h")
 *  2. (optional) refine tableLog using HUF_optimalTableLog()
 *  3. build Huffman table from count using HUF_buildCTable()
 *  4. save Huffman table to memory buffer using HUF_writeCTable()
 *  5. encode the data stream using HUF_compress4X_usingCTable()
 *
 *  The following API allows targeting specific sub-functions for advanced tasks.
 *  For example, it's possible to compress several blocks using the same 'CTable',
 *  or to save and regenerate 'CTable' using external methods.
 */
unsigned HUF_minTableLog(unsigned symbolCardinality);
unsigned HUF_cardinality(const unsigned* count, unsigned maxSymbolValue);
unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, void* workSpace,
 size_t wkspSize, HUF_CElt* table, const unsigned* count, int flags); /* table is used as scratch space for building and testing tables, not a return value */
size_t HUF_writeCTable_wksp(void* dst, size_t maxDstSize, const HUF_CElt* CTable, unsigned maxSymbolValue, unsigned huffLog, void* workspace, size_t workspaceSize);
size_t HUF_compress4X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable, int flags);
size_t HUF_estimateCompressedSize(const HUF_CElt* CTable, const unsigned* count, unsigned maxSymbolValue);
int HUF_validateCTable(const HUF_CElt* CTable, const unsigned* count, unsigned maxSymbolValue);

typedef enum {
   HUF_repeat_none,  /**< Cannot use the previous table */
   HUF_repeat_check, /**< Can use the previous table but it must be checked. Note : The previous table must have been constructed by HUF_compress{1, 4}X_repeat */
   HUF_repeat_valid  /**< Can use the previous table and it is assumed to be valid */
 } HUF_repeat;

/** HUF_compress4X_repeat() :
 *  Same as HUF_compress4X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none.
 *  If it uses hufTable it does not modify hufTable or repeat.
 *  If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used.
 *  If preferRepeat then the old table will always be used if valid.
 *  If suspectUncompressible then some sampling checks will be run to potentially skip huffman coding */
size_t HUF_compress4X_repeat(void* dst, size_t dstSize,
                       const void* src, size_t srcSize,
                       unsigned maxSymbolValue, unsigned tableLog,
                       void* workSpace, size_t wkspSize,    /**< `workSpace` must be aligned on 4-bytes boundaries, `wkspSize` must be >= HUF_WORKSPACE_SIZE */
                       HUF_CElt* hufTable, HUF_repeat* repeat, int flags);

/** HUF_buildCTable_wksp() :
 *  Same as HUF_buildCTable(), but using externally allocated scratch buffer.
 * `workSpace` must be aligned on 4-bytes boundaries, and its size must be >= HUF_CTABLE_WORKSPACE_SIZE.
 */
#define HUF_CTABLE_WORKSPACE_SIZE_U32 ((4 * (HUF_SYMBOLVALUE_MAX + 1)) + 192)
#define HUF_CTABLE_WORKSPACE_SIZE (HUF_CTABLE_WORKSPACE_SIZE_U32 * sizeof(unsigned))
size_t HUF_buildCTable_wksp (HUF_CElt* tree,
                       const unsigned* count, U32 maxSymbolValue, U32 maxNbBits,
                             void* workSpace, size_t wkspSize);

/*! HUF_readStats() :
 *  Read compact Huffman tree, saved by HUF_writeCTable().
 * `huffWeight` is destination buffer.
 * @return : size read from `src` , or an error Code .
 *  Note : Needed by HUF_readCTable() and HUF_readDTableXn() . */
size_t HUF_readStats(BYTE* huffWeight, size_t hwSize,
                     U32* rankStats, U32* nbSymbolsPtr, U32* tableLogPtr,
                     const void* src, size_t srcSize);

/*! HUF_readStats_wksp() :
 * Same as HUF_readStats() but takes an external workspace which must be
 * 4-byte aligned and its size must be >= HUF_READ_STATS_WORKSPACE_SIZE.
 * If the CPU has BMI2 support, pass bmi2=1, otherwise pass bmi2=0.
 */
#define HUF_READ_STATS_WORKSPACE_SIZE_U32 FSE_DECOMPRESS_WKSP_SIZE_U32(6, HUF_TABLELOG_MAX-1)
#define HUF_READ_STATS_WORKSPACE_SIZE (HUF_READ_STATS_WORKSPACE_SIZE_U32 * sizeof(unsigned))
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 flags);

/** HUF_readCTable() :
 *  Loading a CTable saved with HUF_writeCTable() */
size_t HUF_readCTable (HUF_CElt* CTable, unsigned* maxSymbolValuePtr, const void* src, size_t srcSize, unsigned *hasZeroWeights);

/** HUF_getNbBitsFromCTable() :
 *  Read nbBits from CTable symbolTable, for symbol `symbolValue` presumed <= HUF_SYMBOLVALUE_MAX
 *  Note 1 : is not inlined, as HUF_CElt definition is private */
U32 HUF_getNbBitsFromCTable(const HUF_CElt* symbolTable, U32 symbolValue);

/*
 * HUF_decompress() does the following:
 * 1. select the decompression algorithm (X1, X2) based on pre-computed heuristics
 * 2. build Huffman table from save, using HUF_readDTableX?()
 * 3. decode 1 or 4 segments in parallel using HUF_decompress?X?_usingDTable()
 */

/** HUF_selectDecoder() :
 *  Tells which decoder is likely to decode faster,
 *  based on a set of pre-computed metrics.
 * @return : 0==HUF_decompress4X1, 1==HUF_decompress4X2 .
 *  Assumption : 0 < dstSize <= 128 KB */
U32 HUF_selectDecoder (size_t dstSize, size_t cSrcSize);

/**
 *  The minimum workspace size for the `workSpace` used in
 *  HUF_readDTableX1_wksp() and HUF_readDTableX2_wksp().
 *
 *  The space used depends on HUF_TABLELOG_MAX, ranging from ~1500 bytes when
 *  HUF_TABLE_LOG_MAX=12 to ~1850 bytes when HUF_TABLE_LOG_MAX=15.
 *  Buffer overflow errors may potentially occur if code modifications result in
 *  a required workspace size greater than that specified in the following
 *  macro.
 */
#define HUF_DECOMPRESS_WORKSPACE_SIZE ((2 << 10) + (1 << 9))
#define HUF_DECOMPRESS_WORKSPACE_SIZE_U32 (HUF_DECOMPRESS_WORKSPACE_SIZE / sizeof(U32))


/* ====================== */
/* single stream variants */
/* ====================== */

size_t HUF_compress1X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable, int flags);
/** HUF_compress1X_repeat() :
 *  Same as HUF_compress1X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none.
 *  If it uses hufTable it does not modify hufTable or repeat.
 *  If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used.
 *  If preferRepeat then the old table will always be used if valid.
 *  If suspectUncompressible then some sampling checks will be run to potentially skip huffman coding */
size_t HUF_compress1X_repeat(void* dst, size_t dstSize,
                       const void* src, size_t srcSize,
                       unsigned maxSymbolValue, unsigned tableLog,
                       void* workSpace, size_t wkspSize,   /**< `workSpace` must be aligned on 4-bytes boundaries, `wkspSize` must be >= HUF_WORKSPACE_SIZE */
                       HUF_CElt* hufTable, HUF_repeat* repeat, int flags);

size_t HUF_decompress1X_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize, int flags);
#ifndef HUF_FORCE_DECOMPRESS_X1
size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize, int flags);   /**< double-symbols decoder */
#endif

/* BMI2 variants.
 * If the CPU has BMI2 support, pass bmi2=1, otherwise pass bmi2=0.
 */
size_t HUF_decompress1X_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable, int flags);
#ifndef HUF_FORCE_DECOMPRESS_X2
size_t HUF_decompress1X1_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize, int flags);
#endif
size_t HUF_decompress4X_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable, int flags);
size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize, int flags);
#ifndef HUF_FORCE_DECOMPRESS_X2
size_t HUF_readDTableX1_wksp(HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize, int flags);
#endif
#ifndef HUF_FORCE_DECOMPRESS_X1
size_t HUF_readDTableX2_wksp(HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize, int flags);
#endif

#endif   /* HUF_H_298734234 */

#if defined (__cplusplus)
}
#endif
Commit	Line	Data
648db22b	1	/* ******************************************************************
	2	* huff0 huffman codec,
	3	* part of Finite State Entropy library
	4	* Copyright (c) Meta Platforms, Inc. and affiliates.
	5	*
	6	* You can contact the author at :
	7	* - Source repository : https://github.com/Cyan4973/FiniteStateEntropy
	8	*
	9	* This source code is licensed under both the BSD-style license (found in the
	10	* LICENSE file in the root directory of this source tree) and the GPLv2 (found
	11	* in the COPYING file in the root directory of this source tree).
	12	* You may select, at your option, one of the above-listed licenses.
	13	****************************************************************** */
	14
	15	#if defined (__cplusplus)
	16	extern "C" {
	17	#endif
	18
	19	#ifndef HUF_H_298734234
	20	#define HUF_H_298734234
	21
	22	/* * Dependencies * */
	23	#include "zstd_deps.h" /* size_t */
	24	#include "mem.h" /* U32 */
	25	#define FSE_STATIC_LINKING_ONLY
	26	#include "fse.h"
	27
	28
	29	/* * Tool functions * */
	30	#define HUF_BLOCKSIZE_MAX (128 * 1024) /*< maximum input size for a single block compressed with HUF_compress /
	31	size_t HUF_compressBound(size_t size); /*< maximum compressed size (worst case) /
	32
	33	/* Error Management */
	34	unsigned HUF_isError(size_t code); /*< tells if a return value is an error code /
	35	const char* HUF_getErrorName(size_t code); /*< provides error code string (useful for debugging) /
	36
	37
	38	#define HUF_WORKSPACE_SIZE ((8 << 10) + 512 /* sorting scratch space */)
	39	#define HUF_WORKSPACE_SIZE_U64 (HUF_WORKSPACE_SIZE / sizeof(U64))
	40
	41	/* * Constants * */
	42	#define HUF_TABLELOG_MAX 12 /* max runtime value of tableLog (due to static allocation); can be modified up to HUF_TABLELOG_ABSOLUTEMAX */
	43	#define HUF_TABLELOG_DEFAULT 11 /* default tableLog value when none specified */
	44	#define HUF_SYMBOLVALUE_MAX 255
	45
	46	#define HUF_TABLELOG_ABSOLUTEMAX 12 /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */
	47	#if (HUF_TABLELOG_MAX > HUF_TABLELOG_ABSOLUTEMAX)
	48	# error "HUF_TABLELOG_MAX is too large !"
	49	#endif
	50
	51
	52	/* ****************************************
	53	* Static allocation
	54	******************************************/
	55	/* HUF buffer bounds */
	56	#define HUF_CTABLEBOUND 129
	57	#define HUF_BLOCKBOUND(size) (size + (size>>8) + 8) /* only true when incompressible is pre-filtered with fast heuristic */
	58	#define HUF_COMPRESSBOUND(size) (HUF_CTABLEBOUND + HUF_BLOCKBOUND(size)) /* Macro version, useful for static allocation */
	59
	60	/* static allocation of HUF's Compression Table */
	61	/* this is a private definition, just exposed for allocation and strict aliasing purpose. never EVER access its members directly */
	62	typedef size_t HUF_CElt; /* consider it an incomplete type */
	63	#define HUF_CTABLE_SIZE_ST(maxSymbolValue) ((maxSymbolValue)+2) /* Use tables of size_t, for proper alignment */
	64	#define HUF_CTABLE_SIZE(maxSymbolValue) (HUF_CTABLE_SIZE_ST(maxSymbolValue) * sizeof(size_t))
65	#define HUF_CREATE_STATIC_CTABLE(name, maxSymbolValue) \
66	HUF_CElt name[HUF_CTABLE_SIZE_ST(maxSymbolValue)] /* no final ; */
67
68	/* static allocation of HUF's DTable */
69	typedef U32 HUF_DTable;
70	#define HUF_DTABLE_SIZE(maxTableLog) (1 + (1<<(maxTableLog)))
71	#define HUF_CREATE_STATIC_DTABLEX1(DTable, maxTableLog) \
72	HUF_DTable DTable[HUF_DTABLE_SIZE((maxTableLog)-1)] = { ((U32)((maxTableLog)-1) * 0x01000001) }
73	#define HUF_CREATE_STATIC_DTABLEX2(DTable, maxTableLog) \
74	HUF_DTable DTable[HUF_DTABLE_SIZE(maxTableLog)] = { ((U32)(maxTableLog) * 0x01000001) }
75
76
77	/* ****************************************
78	* Advanced decompression functions
79	******************************************/
80
81	/**
82	* Huffman flags bitset.
83	* For all flags, 0 is the default value.
84	*/
85	typedef enum {
86	/**
87	* If compiled with DYNAMIC_BMI2: Set flag only if the CPU supports BMI2 at runtime.
88	* Otherwise: Ignored.
89	*/
90	HUF_flags_bmi2 = (1 << 0),
91	/**
92	* If set: Test possible table depths to find the one that produces the smallest header + encoded size.
93	* If unset: Use heuristic to find the table depth.
94	*/
95	HUF_flags_optimalDepth = (1 << 1),
96	/**
97	* If set: If the previous table can encode the input, always reuse the previous table.
98	* If unset: If the previous table can encode the input, reuse the previous table if it results in a smaller output.
99	*/
100	HUF_flags_preferRepeat = (1 << 2),
101	/**
102	* If set: Sample the input and check if the sample is uncompressible, if it is then don't attempt to compress.
103	* If unset: Always histogram the entire input.
104	*/
105	HUF_flags_suspectUncompressible = (1 << 3),
106	/**
107	* If set: Don't use assembly implementations
108	* If unset: Allow using assembly implementations
109	*/
110	HUF_flags_disableAsm = (1 << 4),
111	/**
112	* If set: Don't use the fast decoding loop, always use the fallback decoding loop.
113	* If unset: Use the fast decoding loop when possible.
114	*/
115	HUF_flags_disableFast = (1 << 5)
116	} HUF_flags_e;
117
118
119	/* ****************************************
120	* HUF detailed API
121	* ****************************************/
122	#define HUF_OPTIMAL_DEPTH_THRESHOLD ZSTD_btultra
123
124	/*! HUF_compress() does the following:
125	* 1. count symbol occurrence from source[] into table count[] using FSE_count() (exposed within "fse.h")
126	* 2. (optional) refine tableLog using HUF_optimalTableLog()
127	* 3. build Huffman table from count using HUF_buildCTable()
128	* 4. save Huffman table to memory buffer using HUF_writeCTable()
129	* 5. encode the data stream using HUF_compress4X_usingCTable()
130	*
131	* The following API allows targeting specific sub-functions for advanced tasks.
132	* For example, it's possible to compress several blocks using the same 'CTable',
133	* or to save and regenerate 'CTable' using external methods.
134	*/
135	unsigned HUF_minTableLog(unsigned symbolCardinality);
136	unsigned HUF_cardinality(const unsigned* count, unsigned maxSymbolValue);
137	unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, void* workSpace,
138	size_t wkspSize, HUF_CElt* table, const unsigned* count, int flags); /* table is used as scratch space for building and testing tables, not a return value */
139	size_t HUF_writeCTable_wksp(void* dst, size_t maxDstSize, const HUF_CElt* CTable, unsigned maxSymbolValue, unsigned huffLog, void* workspace, size_t workspaceSize);
140	size_t HUF_compress4X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable, int flags);
141	size_t HUF_estimateCompressedSize(const HUF_CElt* CTable, const unsigned* count, unsigned maxSymbolValue);
142	int HUF_validateCTable(const HUF_CElt* CTable, const unsigned* count, unsigned maxSymbolValue);
143
144	typedef enum {
145	HUF_repeat_none, /*< Cannot use the previous table /
146	HUF_repeat_check, /*< Can use the previous table but it must be checked. Note : The previous table must have been constructed by HUF_compress{1, 4}X_repeat /
147	HUF_repeat_valid /*< Can use the previous table and it is assumed to be valid /
148	} HUF_repeat;
149
150	/** HUF_compress4X_repeat() :
151	* Same as HUF_compress4X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none.
152	* If it uses hufTable it does not modify hufTable or repeat.
153	* If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used.
154	* If preferRepeat then the old table will always be used if valid.
155	* If suspectUncompressible then some sampling checks will be run to potentially skip huffman coding */
156	size_t HUF_compress4X_repeat(void* dst, size_t dstSize,
157	const void* src, size_t srcSize,
158	unsigned maxSymbolValue, unsigned tableLog,
159	void* workSpace, size_t wkspSize, /*< `workSpace` must be aligned on 4-bytes boundaries, `wkspSize` must be >= HUF_WORKSPACE_SIZE /
160	HUF_CElt* hufTable, HUF_repeat* repeat, int flags);
161
162	/** HUF_buildCTable_wksp() :
163	* Same as HUF_buildCTable(), but using externally allocated scratch buffer.
164	* `workSpace` must be aligned on 4-bytes boundaries, and its size must be >= HUF_CTABLE_WORKSPACE_SIZE.
165	*/
166	#define HUF_CTABLE_WORKSPACE_SIZE_U32 ((4 * (HUF_SYMBOLVALUE_MAX + 1)) + 192)
167	#define HUF_CTABLE_WORKSPACE_SIZE (HUF_CTABLE_WORKSPACE_SIZE_U32 * sizeof(unsigned))
168	size_t HUF_buildCTable_wksp (HUF_CElt* tree,
169	const unsigned* count, U32 maxSymbolValue, U32 maxNbBits,
170	void* workSpace, size_t wkspSize);
171
172	/*! HUF_readStats() :
173	* Read compact Huffman tree, saved by HUF_writeCTable().
174	* `huffWeight` is destination buffer.
175	* @return : size read from `src` , or an error Code .
176	* Note : Needed by HUF_readCTable() and HUF_readDTableXn() . */
177	size_t HUF_readStats(BYTE* huffWeight, size_t hwSize,
178	U32* rankStats, U32* nbSymbolsPtr, U32* tableLogPtr,
179	const void* src, size_t srcSize);
180
181	/*! HUF_readStats_wksp() :
182	* Same as HUF_readStats() but takes an external workspace which must be
183	* 4-byte aligned and its size must be >= HUF_READ_STATS_WORKSPACE_SIZE.
184	* If the CPU has BMI2 support, pass bmi2=1, otherwise pass bmi2=0.
185	*/
186	#define HUF_READ_STATS_WORKSPACE_SIZE_U32 FSE_DECOMPRESS_WKSP_SIZE_U32(6, HUF_TABLELOG_MAX-1)
187	#define HUF_READ_STATS_WORKSPACE_SIZE (HUF_READ_STATS_WORKSPACE_SIZE_U32 * sizeof(unsigned))
188	size_t HUF_readStats_wksp(BYTE* huffWeight, size_t hwSize,
189	U32* rankStats, U32* nbSymbolsPtr, U32* tableLogPtr,
190	const void* src, size_t srcSize,
191	void* workspace, size_t wkspSize,
192	int flags);
193
194	/** HUF_readCTable() :
195	* Loading a CTable saved with HUF_writeCTable() */
196	size_t HUF_readCTable (HUF_CElt* CTable, unsigned* maxSymbolValuePtr, const void* src, size_t srcSize, unsigned *hasZeroWeights);
197
198	/** HUF_getNbBitsFromCTable() :
199	* Read nbBits from CTable symbolTable, for symbol `symbolValue` presumed <= HUF_SYMBOLVALUE_MAX
200	* Note 1 : is not inlined, as HUF_CElt definition is private */
201	U32 HUF_getNbBitsFromCTable(const HUF_CElt* symbolTable, U32 symbolValue);
202
203	/*
204	* HUF_decompress() does the following:
205	* 1. select the decompression algorithm (X1, X2) based on pre-computed heuristics
206	* 2. build Huffman table from save, using HUF_readDTableX?()
207	* 3. decode 1 or 4 segments in parallel using HUF_decompress?X?_usingDTable()
208	*/
209
210	/** HUF_selectDecoder() :
211	* Tells which decoder is likely to decode faster,
212	* based on a set of pre-computed metrics.
213	* @return : 0==HUF_decompress4X1, 1==HUF_decompress4X2 .
214	* Assumption : 0 < dstSize <= 128 KB */
215	U32 HUF_selectDecoder (size_t dstSize, size_t cSrcSize);
216
217	/**
218	* The minimum workspace size for the `workSpace` used in
219	* HUF_readDTableX1_wksp() and HUF_readDTableX2_wksp().
220	*
221	* The space used depends on HUF_TABLELOG_MAX, ranging from ~1500 bytes when
222	* HUF_TABLE_LOG_MAX=12 to ~1850 bytes when HUF_TABLE_LOG_MAX=15.
223	* Buffer overflow errors may potentially occur if code modifications result in
224	* a required workspace size greater than that specified in the following
225	* macro.
226	*/
227	#define HUF_DECOMPRESS_WORKSPACE_SIZE ((2 << 10) + (1 << 9))
228	#define HUF_DECOMPRESS_WORKSPACE_SIZE_U32 (HUF_DECOMPRESS_WORKSPACE_SIZE / sizeof(U32))
229
230
231	/* ====================== */
232	/* single stream variants */
233	/* ====================== */
234
235	size_t HUF_compress1X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable, int flags);
236	/** HUF_compress1X_repeat() :
237	* Same as HUF_compress1X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none.
238	* If it uses hufTable it does not modify hufTable or repeat.
239	* If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used.
240	* If preferRepeat then the old table will always be used if valid.
241	* If suspectUncompressible then some sampling checks will be run to potentially skip huffman coding */
242	size_t HUF_compress1X_repeat(void* dst, size_t dstSize,
243	const void* src, size_t srcSize,
244	unsigned maxSymbolValue, unsigned tableLog,
245	void* workSpace, size_t wkspSize, /*< `workSpace` must be aligned on 4-bytes boundaries, `wkspSize` must be >= HUF_WORKSPACE_SIZE /
246	HUF_CElt* hufTable, HUF_repeat* repeat, int flags);
247
248	size_t HUF_decompress1X_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize, int flags);
249	#ifndef HUF_FORCE_DECOMPRESS_X1
250	size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize, int flags); /*< double-symbols decoder /
251	#endif
252
253	/* BMI2 variants.
254	* If the CPU has BMI2 support, pass bmi2=1, otherwise pass bmi2=0.
255	*/
256	size_t HUF_decompress1X_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable, int flags);
257	#ifndef HUF_FORCE_DECOMPRESS_X2
258	size_t HUF_decompress1X1_DCtx_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize, int flags);
259	#endif
260	size_t HUF_decompress4X_usingDTable(void* dst, size_t maxDstSize, const void* cSrc, size_t cSrcSize, const HUF_DTable* DTable, int flags);
261	size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable* dctx, void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize, void* workSpace, size_t wkspSize, int flags);
262	#ifndef HUF_FORCE_DECOMPRESS_X2
263	size_t HUF_readDTableX1_wksp(HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize, int flags);
264	#endif
265	#ifndef HUF_FORCE_DECOMPRESS_X1
266	size_t HUF_readDTableX2_wksp(HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize, int flags);
267	#endif
268
269	#endif /* HUF_H_298734234 */
270
271	#if defined (__cplusplus)
272	}
273	#endif