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combined price function

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This commit is contained in:
inikep 2016-02-24 14:40:30 +01:00
parent 4a981f7937
commit ee55628c9d
3 changed files with 44 additions and 13 deletions
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2
lib/zstd_internal.h
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@ -184,6 +184,8 @@ typedef struct {
U32 realLitSum;
U32 realSeqSum;
U32 realRepSum;
U32 factor;
U32 factor2;
U32 priceFunc;
} seqStore_t;

35
lib/zstd_opt.h
View File

@ -48,12 +48,14 @@ FORCE_INLINE U32 ZSTD_GETPRICE(seqStore_t* seqStorePtr, U32 litLength, const BYT
switch (seqStorePtr->priceFunc)
{
default:
default:
case 0:
return price + ((seqStorePtr->litSum>>4) / seqStorePtr->litLengthSum);
return price + seqStorePtr->factor + ((seqStorePtr->litSum>>5) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum));
case 1:
return price + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum));
return price + seqStorePtr->factor + ((seqStorePtr->factor2) ? ((seqStorePtr->litSum>>5) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum)) : 0);
case 2:
return price + seqStorePtr->factor + ((seqStorePtr->factor2) ? ((seqStorePtr->litSum>>4) / seqStorePtr->litLengthSum) + ((seqStorePtr->litSum<<1) / (seqStorePtr->litSum + seqStorePtr->matchSum)) : 0);
case 3:
return price;
}
}
@ -264,6 +266,33 @@ void ZSTD_COMPRESSBLOCK_OPT_GENERIC(ZSTD_CCtx* ctx,
ZSTD_rescaleFreqs(seqStorePtr);
if ((ip-base) < REPCODE_STARTVALUE) ip = base + REPCODE_STARTVALUE;
size_t mostFrequent;
unsigned count[256], maxSymbolValue, usedSymbols = 0;
maxSymbolValue = 255;
mostFrequent = FSE_count(count, &maxSymbolValue, src, srcSize);
for (unsigned i=0; i<=maxSymbolValue; i++)
if (count[i]) usedSymbols++;
seqStorePtr->factor = ((usedSymbols <= 18) && (mostFrequent < (1<<14))) ? mostFrequent>>10 : 0; // helps RTF files
seqStorePtr->factor2 = (usedSymbols==256) && (mostFrequent > (1<<14));
#if 0
if (seqStorePtr->factor2)
printf("FACTOR2 usedSymbols==256;mostFrequent>(1<<14) maxSymbolValue=%d mostFrequent=%d usedSymbols=%d\n", maxSymbolValue, (int)mostFrequent, usedSymbols);
if (seqStorePtr->factor) {
printf("FACTOR1 usedSymbols<56;mostFrequent<(1<<14) maxSymbolValue=%d mostFrequent=%d usedSymbols=%d\n", maxSymbolValue, (int)mostFrequent, usedSymbols);
#if 0
for (int i=0; i<256; i++)
if (count[i]) printf("%d=%d ", i, count[i]);
printf("\n");
#endif
}
#endif
/* Match Loop */
while (ip < ilimit) {
U32 u;

20
lib/zstd_opt_internal.h
View File

@ -43,7 +43,7 @@
#define ZSTD_OPT_NUM (1<<12)
#define ZSTD_FREQ_START 1
#define ZSTD_FREQ_STEP 1
#define ZSTD_FREQ_DIV 4
#define ZSTD_FREQ_DIV 5
/*- Debug -*/
#if defined(ZSTD_OPT_DEBUG) && ZSTD_OPT_DEBUG>=9
@ -77,20 +77,20 @@ MEM_STATIC void ZSTD_rescaleFreqs(seqStore_t* ssPtr)
unsigned u;
if (ssPtr->litLengthSum == 0) {
ssPtr->matchLengthSum = (1<<MLbits);
ssPtr->litLengthSum = (1<<LLbits);
ssPtr->litSum = (1<<Litbits);
ssPtr->offCodeSum = (1<<Offbits);
ssPtr->matchSum = 0;
ssPtr->matchLengthSum = ZSTD_FREQ_START*(1<<MLbits);
ssPtr->litLengthSum = ZSTD_FREQ_START*(1<<LLbits);
ssPtr->litSum = ZSTD_FREQ_START*(1<<Litbits);
ssPtr->offCodeSum = ZSTD_FREQ_START*(1<<Offbits);
ssPtr->matchSum = ZSTD_FREQ_START*ssPtr->litSum;
for (u=0; u<=MaxLit; u++)
ssPtr->litFreq[u] = 1;
ssPtr->litFreq[u] = ZSTD_FREQ_START;
for (u=0; u<=MaxLL; u++)
ssPtr->litLengthFreq[u] = 1;
ssPtr->litLengthFreq[u] = ZSTD_FREQ_START;
for (u=0; u<=MaxML; u++)
ssPtr->matchLengthFreq[u] = 1;
ssPtr->matchLengthFreq[u] = ZSTD_FREQ_START;
for (u=0; u<=MaxOff; u++)
ssPtr->offCodeFreq[u] = 1;
ssPtr->offCodeFreq[u] = ZSTD_FREQ_START;
} else {
ssPtr->matchLengthSum = 0;
ssPtr->litLengthSum = 0;