AuroraMiddleware/zstd
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better repcodes

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This commit is contained in:
inikep 2016-03-21 19:48:54 +01:00
parent fc1d7bd93b
commit 378be62a9e
1 changed files with 12 additions and 16 deletions
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26
lib/zstd_opt.h
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@ -444,21 +444,23 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
opt[0].litlen = (U32)(ip - litstart);
/* check repCode */
if (MEM_readMINMATCH(ip+1, minMatch) == MEM_readMINMATCH(ip+1 - rep[0], minMatch)) {
for (int i=0; i<ZSTD_REP_NUM; i++)
if (MEM_readMINMATCH(ip, minMatch) == MEM_readMINMATCH(ip - rep[i], minMatch)) {
/* repcode : we take it */
mlen = (U32)ZSTD_count(ip+1+minMatch, ip+1+minMatch-rep[0], iend) + minMatch;
mlen = (U32)ZSTD_count(ip+minMatch, ip+minMatch-rep[i], iend) + minMatch;
best_off = (i<=1 && ip == anchor) ? 1-i : i;
ZSTD_LOG_PARSER("%d: start try REP rep=%d mlen=%d\n", (int)(ip-base), (int)rep[0], (int)mlen);
ZSTD_LOG_PARSER("%d: start try REP rep=%d mlen=%d\n", (int)(ip-base), (int)rep[i], (int)mlen);
if (depth==0 || mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) {
ip+=1; best_mlen = mlen; best_off = 0; cur = 0; last_pos = 1;
best_mlen = mlen; best_off = i; cur = 0; last_pos = 1;
goto _storeSequence;
}
litlen = opt[0].litlen + 1;
litlen = opt[0].litlen;
do {
price = ZSTD_getPrice(seqStorePtr, litlen, litstart, 0, mlen - minMatch);
if (mlen + 1 > last_pos || price < opt[mlen + 1].price)
SET_PRICE(mlen + 1, mlen, 0, litlen, price); /* note : macro modifies last_pos */
price = ZSTD_getPrice(seqStorePtr, litlen, litstart, best_off, mlen - minMatch);
if (mlen > last_pos || price < opt[mlen].price)
SET_PRICE(mlen, mlen, i, litlen, price); /* note : macro modifies last_pos */
mlen--;
} while (mlen >= minMatch);
}
@ -531,7 +533,7 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
ZSTD_LOG_ENCODE("%d: COPYREP_OFF cur=%d mlen=%d rep=%d rep[1]=%d\n", (int)(inr-base), cur, mlen, opt[cur].rep[0], opt[cur].rep[1]);
} else {
#if 1
if (cur!=mlen && opt[cur].litlen == 0) {
if (opt[cur].litlen == 0) {
opt[cur].rep[0] = opt[cur-mlen].rep[1];
opt[cur].rep[1] = opt[cur-mlen].rep[0];
opt[cur].rep[2] = opt[cur-mlen].rep[2];
@ -572,9 +574,7 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) {
best_mlen = mlen;
#if 1
best_off = i;
#endif
ZSTD_LOG_PARSER("%d: REP sufficient_len=%d best_mlen=%d best_off=%d last_pos=%d\n", (int)(inr-base), sufficient_len, best_mlen, best_off, last_pos);
last_pos = cur + 1;
goto _storeSequence;
@ -596,11 +596,7 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
do {
if (cur + mlen > last_pos || price <= opt[cur + mlen].price)
#if 1
SET_PRICE(cur + mlen, mlen, i, litlen, price);
#else
SET_PRICE(cur + mlen, mlen, best_off, litlen, price);
#endif
mlen--;
} while (mlen >= minMatch);
}