Small LZSA2 speedup in forward arrivals parser

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Emmanuel Marty 2022-04-05 07:13:03 +02:00 committed by GitHub
parent 81fd3af0b3
commit ae942d4eec
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1 changed files with 6 additions and 4 deletions

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@ -309,6 +309,7 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
arrival[i + j].cost = 0x40000000;
}
arrival[nStartOffset << ARRIVALS_PER_POSITION_SHIFT].cost = 0;
arrival[nStartOffset << ARRIVALS_PER_POSITION_SHIFT].from_slot = -1;
if (nInsertForwardReps) {
@ -321,7 +322,7 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
int j, m;
for (j = 0; j < nArrivalsPerPosition && cur_arrival[j].from_slot; j++) {
const int nPrevCost = cur_arrival[j].cost & 0x3fffffff;
const int nPrevCost = cur_arrival[j].cost;
int nCodingChoiceCost = nPrevCost + 8 /* literal */;
const int nScore = cur_arrival[j].score + 1 - nDisableScore;
const int nNumLiterals = cur_arrival[j].num_literals + 1;
@ -476,7 +477,7 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
const int nRepOffset = cur_arrival[j].rep_offset;
if (nMatchOffset != nRepOffset) {
const int nPrevCost = cur_arrival[j].cost & 0x3fffffff;
const int nPrevCost = cur_arrival[j].cost;
const int nScorePenalty = 3 + ((match[m].length & 0x8000) >> 15);
nNoRepmatchOffsetCost = nPrevCost /* the actual cost of the literals themselves accumulates up the chain */;
@ -599,12 +600,13 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
const int nMaskOffset = (j << 7) + (k >> 3);
if (nReduce || !(nRepSlotHandledMask[nMaskOffset] & (1 << (k & 7)))) {
const int nPrevCost = cur_arrival[j].cost & 0x3fffffff;
const int nRepCodingChoiceCost = nPrevCost /* the actual cost of the literals themselves accumulates up the chain */ + nMatchLenCost;
const int nScore = cur_arrival[j].score + 2 - nDisableScore;
const int nRepOffset = cur_arrival[j].rep_offset;
if (nRepOffset != pDestSlots[nArrivalsPerPosition - 1].rep_offset) {
const int nPrevCost = cur_arrival[j].cost;
const int nRepCodingChoiceCost = nPrevCost /* the actual cost of the literals themselves accumulates up the chain */ + nMatchLenCost;
if (nRepCodingChoiceCost < pDestSlots[nArrivalsPerPosition - 1].cost ||
(nRepCodingChoiceCost == pDestSlots[nArrivalsPerPosition - 1].cost && nScore < (pDestSlots[nArrivalsPerPosition - 1].score))) {
int exists = 0, n;