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Compress another 8% faster

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Emmanuel Marty 2020-07-27 13:25:16 +02:00 committed by GitHub
parent b2971da2b4
commit 90fa770458
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GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 8 additions and 1 deletions
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8
src/shrink_block_v2.c
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@ -271,9 +271,11 @@ static void lzsa_insert_forward_match_v2(lzsa_compressor *pCompressor, const uns
static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigned char *pInWindow, lzsa_match *pBestMatch, const int nStartOffset, const int nEndOffset, const int nReduce, const int nInsertForwardReps, const int nArrivalsPerPosition) {
lzsa_arrival *arrival = pCompressor->arrival - (nStartOffset << ARRIVALS_PER_POSITION_SHIFT);
const int* rle_end = (int*)pCompressor->intervals /* reuse */;
char* rep_inserted = pCompressor->rep_inserted;
const int nModeSwitchPenalty = (pCompressor->flags & LZSA_FLAG_FAVOR_RATIO) ? 0 : MODESWITCH_PENALTY;
const int nMinMatchSize = pCompressor->min_match_size;
const int nDisableScore = nReduce ? 0 : (2 * BLOCK_SIZE);
const int nMaxRepInsertedLen = nReduce ? 64 : 0;
const int nLeaveAloneMatchSize = (nArrivalsPerPosition == NARRIVALS_PER_POSITION_V2_SMALL) ? LEAVE_ALONE_MATCH_SIZE_SMALL : LEAVE_ALONE_MATCH_SIZE;
int i, j, n;
@ -382,6 +384,7 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
int nMinRepLen[NARRIVALS_PER_POSITION_V2_BIG];
memset(nMinRepLen, 0, nArrivalsPerPosition * sizeof(int));
memset(rep_inserted, 0, NARRIVALS_PER_POSITION_V2_BIG * (64 / 8) * sizeof(char));
for (j = 0; j < nNumArrivalsForThisPos; j++) {
int nRepOffset = cur_arrival[j].rep_offset;
@ -548,7 +551,7 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
if (k <= nMaxOverallRepLen) {
for (j = 0; j < nNumArrivalsForThisPos; j++) {
if (nMinRepLen[j] >= k) {
if (nMinRepLen[j] >= k && (k >= 64 || (rep_inserted[(j << 3) + (k >> 3)] & (1 << (k & 7))) == 0)) {
const int nPrevCost = cur_arrival[j].cost & 0x3fffffff;
int nRepCodingChoiceCost = nPrevCost /* the actual cost of the literals themselves accumulates up the chain */ + nMatchLenCost;
int nScore = cur_arrival[j].score + 2;
@ -616,6 +619,9 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
}
}
}
if (k < nMaxRepInsertedLen)
rep_inserted[(j << 3) + (k >> 3)] |= (1 << (k & 7));
}
else {
break;

1
src/shrink_context.h
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@ -129,6 +129,7 @@ typedef struct _lzsa_compressor {
int flags;
int safe_dist;
int num_commands;
char rep_inserted[NARRIVALS_PER_POSITION_V2_BIG * (64 / 8)];
lzsa_stats stats;
} lzsa_compressor;