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removed backward match extension

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This commit is contained in:
inikep 2016-02-22 10:11:39 +01:00
parent d3b8d7a4e5
commit c950b78ce2
1 changed files with 24 additions and 34 deletions
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58
lib/zstd_opt.h
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@ -279,7 +279,6 @@ static U32 ZSTD_insertBtAndGetAllMatches (
bestLength = currentMl;
matches[mnum].off = current - matchIndex3;
matches[mnum].len = (U32)currentMl;
matches[mnum].back = 0;
mnum++;
if (currentMl > ZSTD_OPT_NUM) return mnum;
if (ip+currentMl == iLimit) return mnum; /* best possible, and avoid read overflow*/
@ -313,7 +312,6 @@ static U32 ZSTD_insertBtAndGetAllMatches (
bestLength = matchLength;
matches[mnum].off = current - matchIndex;
matches[mnum].len = (U32)matchLength;
matches[mnum].back = 0;
mnum++;
if (matchLength > ZSTD_OPT_NUM) break;
if (ip+matchLength == iLimit) /* equal : no way to know if inf or sup */
@ -422,7 +420,7 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
ZSTD_optimal_t opt[ZSTD_OPT_NUM+4];
ZSTD_match_t matches[ZSTD_OPT_NUM+1];
const BYTE* inr;
U32 cur, cur2, match_num, last_pos, litlen, price;
U32 cur, match_num, last_pos, litlen, price;
const U32 sufficient_len = ctx->params.targetLength;
@ -594,7 +592,6 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
ZSTD_LOG_PARSER("%d: ZSTD_GetAllMatches match_num=%d\n", (int)(inr-base), match_num);
if (match_num > 0 && matches[match_num-1].len > sufficient_len) {
cur -= matches[match_num-1].back;
best_mlen = matches[match_num-1].len;
best_off = matches[match_num-1].off;
last_pos = cur + 1;
@ -606,30 +603,27 @@ void ZSTD_compressBlock_opt_generic(ZSTD_CCtx* ctx,
/* set prices using matches at position = cur */
for (u = 0; u < match_num; u++) {
mlen = (u>0) ? matches[u-1].len+1 : best_mlen;
cur2 = cur - matches[u].back;
best_mlen = (cur2 + matches[u].len < ZSTD_OPT_NUM) ? matches[u].len : ZSTD_OPT_NUM - cur2;
best_mlen = (cur + matches[u].len < ZSTD_OPT_NUM) ? matches[u].len : ZSTD_OPT_NUM - cur;
ZSTD_LOG_PARSER("%d: Found1 cur=%d cur2=%d mlen=%d off=%d best_mlen=%d last_pos=%d\n", (int)(inr-base), cur, cur2, matches[u].len, matches[u].off, best_mlen, last_pos);
if (mlen < matches[u].back + 1)
mlen = matches[u].back + 1;
ZSTD_LOG_PARSER("%d: Found1 cur=%d mlen=%d off=%d best_mlen=%d last_pos=%d\n", (int)(inr-base), cur, matches[u].len, matches[u].off, best_mlen, last_pos);
while (mlen <= best_mlen) {
if (opt[cur2].mlen == 1) {
litlen = opt[cur2].litlen;
if (cur2 > litlen)
price = opt[cur2 - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip+cur2-litlen, matches[u].off, mlen);
if (opt[cur].mlen == 1) {
litlen = opt[cur].litlen;
if (cur > litlen)
price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip+cur-litlen, matches[u].off, mlen);
else
price = ZSTD_getPrice(seqStorePtr, litlen, litstart, matches[u].off, mlen);
} else {
litlen = 0;
price = opt[cur2].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off, mlen);
price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off, mlen);
}
ZSTD_LOG_PARSER("%d: Found2 pred=%d mlen=%d best_mlen=%d off=%d price=%d litlen=%d\n", (int)(inr-base), matches[u].back, mlen, best_mlen, matches[u].off, price, litlen);
ZSTD_LOG_TRY_PRICE("%d: TRY8 price=%d opt[%d].price=%d\n", (int)(inr-base), price, cur2 + mlen, opt[cur2 + mlen].price);
ZSTD_LOG_PARSER("%d: Found2 mlen=%d best_mlen=%d off=%d price=%d litlen=%d\n", (int)(inr-base), mlen, best_mlen, matches[u].off, price, litlen);
ZSTD_LOG_TRY_PRICE("%d: TRY8 price=%d opt[%d].price=%d\n", (int)(inr-base), price, cur + mlen, opt[cur + mlen].price);
if (cur2 + mlen > last_pos || (price < opt[cur2 + mlen].price))
SET_PRICE(cur2 + mlen, mlen, matches[u].off, litlen, price);
if (cur + mlen > last_pos || (price < opt[cur + mlen].price))
SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price);
mlen++;
} } } // for (cur = 1; cur <= last_pos; cur++)
@ -764,7 +758,7 @@ void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx* ctx,
ZSTD_optimal_t opt[ZSTD_OPT_NUM+4];
ZSTD_match_t matches[ZSTD_OPT_NUM+1];
const BYTE* inr;
U32 cur, cur2, match_num, last_pos, litlen, price;
U32 cur, match_num, last_pos, litlen, price;
const U32 sufficient_len = ctx->params.targetLength;
@ -953,7 +947,6 @@ void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx* ctx,
ZSTD_LOG_PARSER("%d: ZSTD_GetAllMatches match_num=%d\n", (int)(inr-base), match_num);
if (match_num > 0 && matches[match_num-1].len > sufficient_len) {
cur -= matches[match_num-1].back;
best_mlen = matches[match_num-1].len;
best_off = matches[match_num-1].off;
last_pos = cur + 1;
@ -963,30 +956,27 @@ void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx* ctx,
// set prices using matches at position = cur
for (u = 0; u < match_num; u++) {
mlen = (u>0) ? matches[u-1].len+1 : best_mlen;
cur2 = cur - matches[u].back;
best_mlen = (cur2 + matches[u].len < ZSTD_OPT_NUM) ? matches[u].len : ZSTD_OPT_NUM - cur2;
best_mlen = (cur + matches[u].len < ZSTD_OPT_NUM) ? matches[u].len : ZSTD_OPT_NUM - cur;
ZSTD_LOG_PARSER("%d: Found1 cur=%d cur2=%d mlen=%d off=%d best_mlen=%d last_pos=%d\n", (int)(inr-base), cur, cur2, matches[u].len, matches[u].off, best_mlen, last_pos);
if (mlen < matches[u].back + 1)
mlen = matches[u].back + 1;
ZSTD_LOG_PARSER("%d: Found1 cur=%d mlen=%d off=%d best_mlen=%d last_pos=%d\n", (int)(inr-base), cur, matches[u].len, matches[u].off, best_mlen, last_pos);
while (mlen <= best_mlen) {
if (opt[cur2].mlen == 1) {
litlen = opt[cur2].litlen;
if (cur2 > litlen)
price = opt[cur2 - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip+cur2-litlen, matches[u].off, mlen);
if (opt[cur].mlen == 1) {
litlen = opt[cur].litlen;
if (cur > litlen)
price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip+cur-litlen, matches[u].off, mlen);
else
price = ZSTD_getPrice(seqStorePtr, litlen, litstart, matches[u].off, mlen);
} else {
litlen = 0;
price = opt[cur2].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off, mlen);
price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off, mlen);
}
ZSTD_LOG_PARSER("%d: Found2 pred=%d mlen=%d best_mlen=%d off=%d price=%d litlen=%d\n", (int)(inr-base), matches[u].back, mlen, best_mlen, matches[u].off, price, litlen);
ZSTD_LOG_TRY_PRICE("%d: TRY8 price=%d opt[%d].price=%d\n", (int)(inr-base), price, cur2 + mlen, opt[cur2 + mlen].price);
ZSTD_LOG_PARSER("%d: Found2 mlen=%d best_mlen=%d off=%d price=%d litlen=%d\n", (int)(inr-base), mlen, best_mlen, matches[u].off, price, litlen);
ZSTD_LOG_TRY_PRICE("%d: TRY8 price=%d opt[%d].price=%d\n", (int)(inr-base), price, cur + mlen, opt[cur + mlen].price);
if (cur2 + mlen > last_pos || (price < opt[cur2 + mlen].price))
SET_PRICE(cur2 + mlen, mlen, matches[u].off, litlen, price);
if (cur + mlen > last_pos || (price < opt[cur + mlen].price))
SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price);
mlen++;
} } } // for (cur = 1; cur <= last_pos; cur++)