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more accurate gain function

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This commit is contained in:
inikep 2016-02-24 18:09:36 +01:00
parent ee55628c9d
commit 02137f8c42
2 changed files with 14 additions and 14 deletions
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14
lib/zstd_opt.h
View File

@ -37,26 +37,26 @@
FORCE_INLINE U32 ZSTD_GETPRICE(seqStore_t* seqStorePtr, U32 litLength, const BYTE* literals, U32 offset, U32 matchLength) FORCE_INLINE U32 ZSTD_GETPRICE(seqStore_t* seqStorePtr, U32 litLength, const BYTE* literals, U32 offset, U32 matchLength)
{ {
/* offset */ /* offset */
BYTE offCode = offset ? (BYTE)ZSTD_highbit(offset) + 1 : 0; BYTE offCode = offset ? (BYTE)ZSTD_highbit(offset+1) + 1 : 0;
U32 price = offCode + ZSTD_highbit(seqStorePtr->offCodeSum) - ZSTD_highbit(seqStorePtr->offCodeFreq[offCode]); U32 price = (offCode-1) + (!offCode) + ZSTD_highbit(seqStorePtr->offCodeSum+1) - ZSTD_highbit(seqStorePtr->offCodeFreq[offCode]+1);
/* match Length */ /* match Length */
matchLength -= MINMATCHOPT; matchLength -= MINMATCHOPT;
price += ((matchLength >= MaxML)<<3) + ((matchLength >= 255+MaxML)<<4) + ((matchLength>=(1<<15))<<3); price += ((matchLength >= MaxML)<<3) + ((matchLength >= 255+MaxML)<<4) + ((matchLength>=(1<<15))<<3);
if (matchLength >= MaxML) matchLength = MaxML; if (matchLength >= MaxML) matchLength = MaxML;
price += ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + ZSTD_highbit(seqStorePtr->matchLengthSum) - ZSTD_highbit(seqStorePtr->matchLengthFreq[matchLength]); price += ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + ZSTD_highbit(seqStorePtr->matchLengthSum+1) - ZSTD_highbit(seqStorePtr->matchLengthFreq[matchLength]+1);
switch (seqStorePtr->priceFunc) switch (seqStorePtr->priceFunc)
{ {
default: default:
case 0: case 0:
return price + seqStorePtr->factor + ((seqStorePtr->litSum>>5) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum)); return 1 + price + seqStorePtr->factor + ((seqStorePtr->litSum>>5) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum));
case 1: case 1:
return price + seqStorePtr->factor + ((seqStorePtr->factor2) ? ((seqStorePtr->litSum>>5) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum)) : 0); return 1 + price + seqStorePtr->factor + ((seqStorePtr->factor2) ? ((seqStorePtr->litSum>>5) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum)) : 0);
case 2: case 2:
return price + seqStorePtr->factor + ((seqStorePtr->factor2) ? ((seqStorePtr->litSum>>4) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum)) : 0); return 1 + price + seqStorePtr->factor + ((seqStorePtr->factor2) ? ((seqStorePtr->litSum>>4) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum)) : 0);
case 3: case 3:
return price; return 1 + price;
} }
} }

12
lib/zstd_opt_internal.h
View File

@ -52,7 +52,7 @@
#define ZSTD_LOG_TRY_PRICE(...) printf(__VA_ARGS__) #define ZSTD_LOG_TRY_PRICE(...) printf(__VA_ARGS__)
#else #else
#define ZSTD_LOG_PARSER(...) #define ZSTD_LOG_PARSER(...)
#define ZSTD_LOG_ENCODE(...) #define ZSTD_LOG_ENCODE(...) // printf(__VA_ARGS__)
#define ZSTD_LOG_TRY_PRICE(...) #define ZSTD_LOG_TRY_PRICE(...)
#endif #endif
@ -136,7 +136,7 @@ MEM_STATIC void ZSTD_updatePrice(seqStore_t* seqStorePtr, U32 litLength, const B
/* match offset */ /* match offset */
seqStorePtr->offCodeSum += ZSTD_FREQ_STEP; seqStorePtr->offCodeSum += ZSTD_FREQ_STEP;
BYTE offCode = offset ? (BYTE)ZSTD_highbit(offset) + 1 : 0; BYTE offCode = offset ? (BYTE)ZSTD_highbit(offset+1) + 1 : 0;
seqStorePtr->offCodeFreq[offCode] += ZSTD_FREQ_STEP; seqStorePtr->offCodeFreq[offCode] += ZSTD_FREQ_STEP;
/* match Length */ /* match Length */
@ -152,17 +152,17 @@ FORCE_INLINE U32 ZSTD_getLiteralPrice(seqStore_t* seqStorePtr, U32 litLength, co
U32 price, u; U32 price, u;
if (litLength == 0) if (litLength == 0)
return ZSTD_highbit(seqStorePtr->litLengthSum) - ZSTD_highbit(seqStorePtr->litLengthFreq[0]); return ZSTD_highbit(seqStorePtr->litLengthSum+1) - ZSTD_highbit(seqStorePtr->litLengthFreq[0]+1);
/* literals */ /* literals */
price = litLength * ZSTD_highbit(seqStorePtr->litSum); price = litLength * ZSTD_highbit(seqStorePtr->litSum+1);
for (u=0; u < litLength; u++) for (u=0; u < litLength; u++)
price -= ZSTD_highbit(seqStorePtr->litFreq[literals[u]]); price -= ZSTD_highbit(seqStorePtr->litFreq[literals[u]]+1);
/* literal Length */ /* literal Length */
price += ((litLength >= MaxLL)<<3) + ((litLength >= 255+MaxLL)<<4) + ((litLength>=(1<<15))<<3); price += ((litLength >= MaxLL)<<3) + ((litLength >= 255+MaxLL)<<4) + ((litLength>=(1<<15))<<3);
if (litLength >= MaxLL) litLength = MaxLL; if (litLength >= MaxLL) litLength = MaxLL;
price += ZSTD_highbit(seqStorePtr->litLengthSum) - ZSTD_highbit(seqStorePtr->litLengthFreq[litLength]); price += ZSTD_highbit(seqStorePtr->litLengthSum+1) - ZSTD_highbit(seqStorePtr->litLengthFreq[litLength]+1);
return price; return price;
} }