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Updated fse (faster huff0 32-bits decoding)

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This commit is contained in:
Yann Collet 2015-07-27 19:34:27 +01:00
parent e8c6bb1e42
commit fb8296f55c
1 changed files with 31 additions and 21 deletions
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52
lib/fse.c
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@ -1656,10 +1656,13 @@ size_t FSE_decompress(void* dst, size_t maxDstSize, const void* cSrc, size_t cSr
/*********************************************************
* Huff0 : Huffman block compression
*********************************************************/
#define HUF_ABSOLUTEMAX_TABLELOG 16
#define HUF_MAX_TABLELOG 13
#define HUF_DEFAULT_TABLELOG 12
#define HUF_MAX_SYMBOL_VALUE 255
#define HUF_DEFAULT_TABLELOG 12 /* used by default, when not specified */
#define HUF_MAX_TABLELOG 12 /* max possible tableLog; for allocation purpose; can be modified */
#define HUF_ABSOLUTEMAX_TABLELOG 16 /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code is unsupported */
#if (HUF_MAX_TABLELOG > HUF_ABSOLUTEMAX_TABLELOG)
# error "HUF_MAX_TABLELOG is too large !"
#endif
typedef struct HUF_CElt_s {
U16 val;
@ -2192,26 +2195,33 @@ static size_t HUF_decompress_usingDTable(
for ( ; (reloadStatus<FSE_DStream_completed) && (op<olimit); /* D2-3-4 are supposed to be synchronized and finish together */
op+=16, reloadStatus = FSE_reloadDStream(&bitD2) | FSE_reloadDStream(&bitD3) | FSE_reloadDStream(&bitD4), FSE_reloadDStream(&bitD1))
{
#define HUF_DECODE_SYMBOL(n, Dstream) \
#define HUF_DECODE_SYMBOL_0(n, Dstream) \
HUF_decodeSymbol(op+n, &Dstream, dt, dtLog);
#define HUF_DECODE_SYMBOL_1(n, Dstream) \
HUF_decodeSymbol(op+n, &Dstream, dt, dtLog); \
if (FSE_32bits() && (HUF_MAX_TABLELOG>12)) FSE_reloadDStream(&Dstream)
#define HUF_DECODE_SYMBOL_2(n, Dstream) \
HUF_decodeSymbol(op+n, &Dstream, dt, dtLog); \
if (FSE_32bits()) FSE_reloadDStream(&Dstream)
HUF_DECODE_SYMBOL( 0, bitD1);
HUF_DECODE_SYMBOL( 1, bitD2);
HUF_DECODE_SYMBOL( 2, bitD3);
HUF_DECODE_SYMBOL( 3, bitD4);
HUF_DECODE_SYMBOL( 4, bitD1);
HUF_DECODE_SYMBOL( 5, bitD2);
HUF_DECODE_SYMBOL( 6, bitD3);
HUF_DECODE_SYMBOL( 7, bitD4);
HUF_DECODE_SYMBOL( 8, bitD1);
HUF_DECODE_SYMBOL( 9, bitD2);
HUF_DECODE_SYMBOL(10, bitD3);
HUF_DECODE_SYMBOL(11, bitD4);
HUF_DECODE_SYMBOL(12, bitD1);
HUF_DECODE_SYMBOL(13, bitD2);
HUF_DECODE_SYMBOL(14, bitD3);
HUF_DECODE_SYMBOL(15, bitD4);
HUF_DECODE_SYMBOL_1( 0, bitD1);
HUF_DECODE_SYMBOL_1( 1, bitD2);
HUF_DECODE_SYMBOL_1( 2, bitD3);
HUF_DECODE_SYMBOL_1( 3, bitD4);
HUF_DECODE_SYMBOL_2( 4, bitD1);
HUF_DECODE_SYMBOL_2( 5, bitD2);
HUF_DECODE_SYMBOL_2( 6, bitD3);
HUF_DECODE_SYMBOL_2( 7, bitD4);
HUF_DECODE_SYMBOL_1( 8, bitD1);
HUF_DECODE_SYMBOL_1( 9, bitD2);
HUF_DECODE_SYMBOL_1(10, bitD3);
HUF_DECODE_SYMBOL_1(11, bitD4);
HUF_DECODE_SYMBOL_0(12, bitD1);
HUF_DECODE_SYMBOL_0(13, bitD2);
HUF_DECODE_SYMBOL_0(14, bitD3);
HUF_DECODE_SYMBOL_0(15, bitD4);
}
if (reloadStatus!=FSE_DStream_completed) /* not complete : some bitStream might be 0 (unfinished) */
@ -2227,7 +2237,7 @@ static size_t HUF_decompress_usingDTable(
bitTail.start = start1;
for ( ; (FSE_reloadDStream(&bitTail) < FSE_DStream_completed) && (op<omax) ; op++)
{
HUF_DECODE_SYMBOL(0, bitTail);
HUF_DECODE_SYMBOL_0(0, bitTail);
}
if (FSE_endOfDStream(&bitTail))