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improved compression speed 

introduced cache in ZSTD_setLog2Prices
dev
inikep 2016-03-09 15:45:01 +01:00
parent 48413765b4
commit b5a519f43c
2 changed files with 31 additions and 11 deletions
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6
lib/zstd_internal.h
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@ -207,6 +207,12 @@ typedef struct {
U32 litLengthSum;
U32 litSum;
U32 offCodeSum;
U32 log2matchLengthSum;
U32 log2matchSum;
U32 log2litLengthSum;
U32 log2litSum;
U32 log2offCodeSum;
U32 factor;
#if ZSTD_OPT_DEBUG == 3
U32 realMatchSum;
U32 realLitSum;

36
lib/zstd_opt.h
View File

@ -39,16 +39,26 @@
/*-*************************************
* Price functions for optimal parser
***************************************/
FORCE_INLINE void ZSTD_setLog2Prices(seqStore_t* ssPtr)
{
ssPtr->log2matchLengthSum = ZSTD_highbit(ssPtr->matchLengthSum+1);
ssPtr->log2litLengthSum = ZSTD_highbit(ssPtr->litLengthSum+1);
ssPtr->log2litSum = ZSTD_highbit(ssPtr->litSum+1);
ssPtr->log2offCodeSum = ZSTD_highbit(ssPtr->offCodeSum+1);
ssPtr->factor = 1 + ((ssPtr->litSum>>5) / ssPtr->litLengthSum) + ((ssPtr->litSum<<1) / (ssPtr->litSum + ssPtr->matchSum));
}
MEM_STATIC void ZSTD_rescaleFreqs(seqStore_t* ssPtr)
{
unsigned u;
if (ssPtr->litLengthSum == 0) {
ssPtr->litSum = 2*(1<<Litbits);
ssPtr->litLengthSum = 1*(1<<LLbits);
ssPtr->matchLengthSum = 1*(1<<MLbits);
ssPtr->offCodeSum = 1*(1<<Offbits);
ssPtr->matchSum = 2*(1<<Litbits);
ssPtr->litSum = (2<<Litbits);
ssPtr->litLengthSum = (1<<LLbits);
ssPtr->matchLengthSum = (1<<MLbits);
ssPtr->offCodeSum = (1<<Offbits);
ssPtr->matchSum = (2<<Litbits);
for (u=0; u<=MaxLit; u++)
ssPtr->litFreq[u] = 2;
@ -83,6 +93,8 @@ MEM_STATIC void ZSTD_rescaleFreqs(seqStore_t* ssPtr)
ssPtr->offCodeSum += ssPtr->offCodeFreq[u];
}
}
ZSTD_setLog2Prices(ssPtr);
}
@ -91,17 +103,17 @@ FORCE_INLINE U32 ZSTD_getLiteralPrice(seqStore_t* seqStorePtr, U32 litLength, co
U32 price, u;
if (litLength == 0)
return ZSTD_highbit(seqStorePtr->litLengthSum+1) - ZSTD_highbit(seqStorePtr->litLengthFreq[0]+1);
return seqStorePtr->log2litLengthSum - ZSTD_highbit(seqStorePtr->litLengthFreq[0]+1);
/* literals */
price = litLength * ZSTD_highbit(seqStorePtr->litSum+1);
price = litLength * seqStorePtr->log2litSum;
for (u=0; u < litLength; u++)
price -= ZSTD_highbit(seqStorePtr->litFreq[literals[u]]+1);
/* literal Length */
price += ((litLength >= MaxLL)<<3) + ((litLength >= 255+MaxLL)<<4) + ((litLength>=(1<<15))<<3);
if (litLength >= MaxLL) litLength = MaxLL;
price += ZSTD_highbit(seqStorePtr->litLengthSum+1) - ZSTD_highbit(seqStorePtr->litLengthFreq[litLength]+1);
price += seqStorePtr->log2litLengthSum - ZSTD_highbit(seqStorePtr->litLengthFreq[litLength]+1);
return price;
}
@ -111,12 +123,12 @@ FORCE_INLINE U32 ZSTD_getPrice(seqStore_t* seqStorePtr, U32 litLength, const BYT
{
/* offset */
BYTE offCode = offset ? (BYTE)ZSTD_highbit(offset+1) + 1 : 0;
U32 price = (offCode-1) + (!offCode) + ZSTD_highbit(seqStorePtr->offCodeSum+1) - ZSTD_highbit(seqStorePtr->offCodeFreq[offCode]+1);
U32 price = (offCode-1) + (!offCode) + seqStorePtr->log2offCodeSum - ZSTD_highbit(seqStorePtr->offCodeFreq[offCode]+1);
/* match Length */
price += ((matchLength >= MaxML)<<3) + ((matchLength >= 255+MaxML)<<4) + ((matchLength>=(1<<15))<<3);
if (matchLength >= MaxML) matchLength = MaxML;
price += ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + ZSTD_highbit(seqStorePtr->matchLengthSum+1) - ZSTD_highbit(seqStorePtr->matchLengthFreq[matchLength]+1);
price += ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + seqStorePtr->log2matchLengthSum - ZSTD_highbit(seqStorePtr->matchLengthFreq[matchLength]+1);
#if ZSTD_OPT_DEBUG == 3
switch (seqStorePtr->priceFunc) {
@ -127,7 +139,7 @@ FORCE_INLINE U32 ZSTD_getPrice(seqStore_t* seqStorePtr, U32 litLength, const BYT
return 1 + price;
}
#else
return 1 + price + ((seqStorePtr->litSum>>5) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum));
return price + seqStorePtr->factor;
#endif
}
@ -159,6 +171,8 @@ MEM_STATIC void ZSTD_updatePrice(seqStore_t* seqStorePtr, U32 litLength, const B
seqStorePtr->matchLengthFreq[MaxML]++;
else
seqStorePtr->matchLengthFreq[matchLength]++;
ZSTD_setLog2Prices(seqStorePtr);
}