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Code Issues Releases 1 Activity

ZSTD_get_price2

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inikep
2016-02-03 19:27:44 +01:00
parent 1292509987
commit 892776efd6
1 changed files with 10 additions and 31 deletions
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41
lib/zstd_opt.c
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@@ -32,32 +32,11 @@ typedef struct
#define ZSTD_OPT_NUM (1<<12)
/*
I assume that you are using 4 entropy-coder tables:
litLength = FSE_decodeSymbol(&(seqState->stateLL), &(seqState->DStream));
offsetCode = FSE_decodeSymbol(&(seqState->stateOffb), &(seqState->DStream));
matchLength = FSE_decodeSymbol(&(seqState->stateML), &(seqState->DStream));
HUF_decompress(dst, litSize, ip+5, litCSize)
With the following max values:
#define MLbits 7
#define LLbits 6
#define Offbits 5
#define MaxML ((1<<MLbits) - 1)
#define MaxLL ((1<<LLbits) - 1)
#define MaxOff ((1<<Offbits)- 1)
When value >= maxValue then use additional 1 byte (if value <
maxValue+255) or 3 bytes (to encode value up to MaxValue+255+65535).
For offsets only the numbers of bits == log2(offset) are
entropy encoded and the offset is put into a binary stream.
*/
#define ZSTD_LIT_ONLY_COST(len) (((len)<<3)+1+0)
#define ZSTD_LIT_COST(len) (((len)<<3)+0)
FORCE_INLINE size_t ZSTD_get_price(seqStore_t* seqStorePtr, size_t litlen, size_t offset, size_t mlen)
FORCE_INLINE size_t ZSTD_get_price(seqStore_t* seqStorePtr, size_t litlen, const BYTE* literals, size_t offset, size_t mlen)
{
size_t lit_cost = (litlen<<3)+0;
size_t match_cost = /*MLbits +*/ ZSTD_highbit((U32)mlen+1) + Offbits + ZSTD_highbit((U32)offset+1);
@@ -576,7 +555,7 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
do
{
litlen = 0;
price = ZSTD_get_price(seqStorePtr, llen + 1, 0, mlen - MINMATCH) - ZSTD_LIT_COST(llen + 1);
price = ZSTD_get_price(seqStorePtr, llen + 1, anchor, 0, mlen - MINMATCH) - ZSTD_LIT_COST(llen + 1);
if (mlen + 1 > last_pos || price < opt[mlen + 1].price)
SET_PRICE(mlen + 1, mlen, 0, litlen, price);
mlen--;
@@ -621,7 +600,7 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
while (mlen <= best_mlen)
{
litlen = 0;
price = ZSTD_get_price(seqStorePtr, llen + litlen, matches[i].off, mlen - MINMATCH) - ZSTD_LIT_COST(llen);
price = ZSTD_get_price(seqStorePtr, llen + litlen, anchor, matches[i].off, mlen - MINMATCH) - ZSTD_LIT_COST(llen);
if (mlen > last_pos || price < opt[mlen].price)
SET_PRICE(mlen, mlen, matches[i].off, litlen, price);
mlen++;
@@ -728,20 +707,20 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
if (cur != litlen)
{
price = opt[cur - litlen].price + ZSTD_get_price(seqStorePtr, litlen, 0, mlen - MINMATCH);
price = opt[cur - litlen].price + ZSTD_get_price(seqStorePtr, litlen, inr-litlen, 0, mlen - MINMATCH);
ZSTD_LOG_TRY_PRICE("%d: TRY5 opt[%d].price=%d price=%d cur=%d litlen=%d\n", (int)(inr-base), cur - litlen, opt[cur - litlen].price, price, cur, litlen);
}
else
{
price = ZSTD_get_price(seqStorePtr, llen + litlen, 0, mlen - MINMATCH) - ZSTD_LIT_COST(llen);
price = ZSTD_get_price(seqStorePtr, llen + litlen, anchor, 0, mlen - MINMATCH) - ZSTD_LIT_COST(llen);
ZSTD_LOG_TRY_PRICE("%d: TRY6 price=%d cur=%d litlen=%d llen=%d\n", (int)(inr-base), price, cur, litlen, llen);
}
}
else
{
litlen = 0;
price = opt[cur].price + ZSTD_get_price(seqStorePtr, litlen, 0, mlen - MINMATCH);
ZSTD_LOG_TRY_PRICE("%d: TRY7 price=%d cur=%d litlen=%d getprice=%d\n", (int)(inr-base), price, cur, litlen, ZSTD_get_price(seqStorePtr, litlen, 0, mlen - MINMATCH));
price = opt[cur].price + ZSTD_get_price(seqStorePtr, 0, NULL, 0, mlen - MINMATCH);
ZSTD_LOG_TRY_PRICE("%d: TRY7 price=%d cur=%d litlen=0 getprice=%d\n", (int)(inr-base), price, cur, ZSTD_get_price(seqStorePtr, 0, NULL, 0, mlen - MINMATCH));
}
best_mlen = mlen;
@@ -800,14 +779,14 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
litlen = opt[cur2].litlen;
if (cur2 != litlen)
price = opt[cur2 - litlen].price + ZSTD_get_price(seqStorePtr, litlen, matches[i].off, mlen - MINMATCH);
price = opt[cur2 - litlen].price + ZSTD_get_price(seqStorePtr, litlen, ip+cur2-litlen, matches[i].off, mlen - MINMATCH);
else
price = ZSTD_get_price(seqStorePtr, llen + litlen, matches[i].off, mlen - MINMATCH) - ZSTD_LIT_COST(llen);
price = ZSTD_get_price(seqStorePtr, llen + litlen, anchor, matches[i].off, mlen - MINMATCH) - ZSTD_LIT_COST(llen);
}
else
{
litlen = 0;
price = opt[cur2].price + ZSTD_get_price(seqStorePtr, litlen, matches[i].off, mlen - MINMATCH);
price = opt[cur2].price + ZSTD_get_price(seqStorePtr, 0, NULL, matches[i].off, mlen - MINMATCH);
}
ZSTD_LOG_PARSER("%d: Found2 pred=%d mlen=%d best_mlen=%d off=%d price=%d litlen=%d price[%d]=%d\n", (int)(inr-base), matches[i].back, mlen, best_mlen, matches[i].off, price, litlen, cur - litlen, opt[cur - litlen].price);