Mercurial > hg
diff contrib/python-zstandard/zstd/common/fse.h @ 30822:b54a2984cdd4
zstd: vendor python-zstandard 0.6.0
Commit 63c68d6f5fc8de4afd9bde81b13b537beb4e47e8 from
https://github.com/indygreg/python-zstandard is imported without
modifications (other than removing unwanted files).
This includes minor performance and feature improvements. It also
changes the vendored zstd library from 1.1.1 to 1.1.2.
# no-check-commit
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Sat, 14 Jan 2017 19:41:43 -0800 |
parents | 2e484bdea8c4 |
children | b1fb341d8a61 |
line wrap: on
line diff
--- a/contrib/python-zstandard/zstd/common/fse.h Sat Jan 14 20:05:15 2017 +0530 +++ b/contrib/python-zstandard/zstd/common/fse.h Sat Jan 14 19:41:43 2017 -0800 @@ -286,7 +286,7 @@ #define FSE_BLOCKBOUND(size) (size + (size>>7)) #define FSE_COMPRESSBOUND(size) (FSE_NCOUNTBOUND + FSE_BLOCKBOUND(size)) /* Macro version, useful for static allocation */ -/* It is possible to statically allocate FSE CTable/DTable as a table of unsigned using below macros */ +/* It is possible to statically allocate FSE CTable/DTable as a table of FSE_CTable/FSE_DTable using below macros */ #define FSE_CTABLE_SIZE_U32(maxTableLog, maxSymbolValue) (1 + (1<<(maxTableLog-1)) + ((maxSymbolValue+1)*2)) #define FSE_DTABLE_SIZE_U32(maxTableLog) (1 + (1<<maxTableLog)) @@ -294,37 +294,72 @@ /* ***************************************** * FSE advanced API *******************************************/ +/* FSE_count_wksp() : + * Same as FSE_count(), but using an externally provided scratch buffer. + * `workSpace` size must be table of >= `1024` unsigned + */ +size_t FSE_count_wksp(unsigned* count, unsigned* maxSymbolValuePtr, + const void* source, size_t sourceSize, unsigned* workSpace); + +/** FSE_countFast() : + * same as FSE_count(), but blindly trusts that all byte values within src are <= *maxSymbolValuePtr + */ size_t FSE_countFast(unsigned* count, unsigned* maxSymbolValuePtr, const void* src, size_t srcSize); -/**< same as FSE_count(), but blindly trusts that all byte values within src are <= *maxSymbolValuePtr */ + +/* FSE_countFast_wksp() : + * Same as FSE_countFast(), but using an externally provided scratch buffer. + * `workSpace` must be a table of minimum `1024` unsigned + */ +size_t FSE_countFast_wksp(unsigned* count, unsigned* maxSymbolValuePtr, const void* src, size_t srcSize, unsigned* workSpace); + +/*! FSE_count_simple + * Same as FSE_countFast(), but does not use any additional memory (not even on stack). + * This function is unsafe, and will segfault if any value within `src` is `> *maxSymbolValuePtr` (presuming it's also the size of `count`). +*/ +size_t FSE_count_simple(unsigned* count, unsigned* maxSymbolValuePtr, const void* src, size_t srcSize); + + unsigned FSE_optimalTableLog_internal(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, unsigned minus); /**< same as FSE_optimalTableLog(), which used `minus==2` */ +/* FSE_compress_wksp() : + * Same as FSE_compress2(), but using an externally allocated scratch buffer (`workSpace`). + * FSE_WKSP_SIZE_U32() provides the minimum size required for `workSpace` as a table of FSE_CTable. + */ +#define FSE_WKSP_SIZE_U32(maxTableLog, maxSymbolValue) ( FSE_CTABLE_SIZE_U32(maxTableLog, maxSymbolValue) + (1<<((maxTableLog>2)?(maxTableLog-2):0)) ) +size_t FSE_compress_wksp (void* dst, size_t dstSize, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void* workSpace, size_t wkspSize); + size_t FSE_buildCTable_raw (FSE_CTable* ct, unsigned nbBits); -/**< build a fake FSE_CTable, designed to not compress an input, where each symbol uses nbBits */ +/**< build a fake FSE_CTable, designed for a flat distribution, where each symbol uses nbBits */ size_t FSE_buildCTable_rle (FSE_CTable* ct, unsigned char symbolValue); /**< build a fake FSE_CTable, designed to compress always the same symbolValue */ +/* FSE_buildCTable_wksp() : + * Same as FSE_buildCTable(), but using an externally allocated scratch buffer (`workSpace`). + * `wkspSize` must be >= `(1<<tableLog)`. + */ +size_t FSE_buildCTable_wksp(FSE_CTable* ct, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void* workSpace, size_t wkspSize); + size_t FSE_buildDTable_raw (FSE_DTable* dt, unsigned nbBits); -/**< build a fake FSE_DTable, designed to read an uncompressed bitstream where each symbol uses nbBits */ +/**< build a fake FSE_DTable, designed to read a flat distribution where each symbol uses nbBits */ size_t FSE_buildDTable_rle (FSE_DTable* dt, unsigned char symbolValue); /**< build a fake FSE_DTable, designed to always generate the same symbolValue */ +size_t FSE_decompress_wksp(void* dst, size_t dstCapacity, const void* cSrc, size_t cSrcSize, FSE_DTable* workSpace, unsigned maxLog); +/**< same as FSE_decompress(), using an externally allocated `workSpace` produced with `FSE_DTABLE_SIZE_U32(maxLog)` */ + /* ***************************************** * FSE symbol compression API *******************************************/ /*! This API consists of small unitary functions, which highly benefit from being inlined. - You will want to enable link-time-optimization to ensure these functions are properly inlined in your binary. - Visual seems to do it automatically. - For gcc or clang, you'll need to add -flto flag at compilation and linking stages. - If none of these solutions is applicable, include "fse.c" directly. + Hence their body are included in next section. */ -typedef struct -{ +typedef struct { ptrdiff_t value; const void* stateTable; const void* symbolTT; @@ -384,8 +419,7 @@ /* ***************************************** * FSE symbol decompression API *******************************************/ -typedef struct -{ +typedef struct { size_t state; const void* table; /* precise table may vary, depending on U16 */ } FSE_DState_t;