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Speed LZSA2 compression up further; fix typo

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This commit is contained in:
Emmanuel Marty
2019-09-19 17:18:37 +02:00
committed by GitHub
parent 1495b27f69
commit 51644ad2f9
1 changed files with 11 additions and 9 deletions
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20
src/shrink_block_v2.c
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@@ -245,7 +245,8 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const int nSt
for (m = 0; m < nMatches; m++) {
int nMatchLen = match[m].length;
int nNoRe_matchOffsetCost = (match[m].offset <= 32) ? 4 : ((match[m].offset <= 512) ? 8 : ((match[m].offset <= (8192 + 512)) ? 12 : 16));
int nMatchOffset = match[m].offset;
int nNoRepmatchOffsetCost = (nMatchOffset <= 32) ? 4 : ((nMatchOffset <= 512) ? 8 : ((nMatchOffset <= (8192 + 512)) ? 12 : 16));
int nStartingMatchLen, k;
if ((i + nMatchLen) > (nEndOffset - LAST_LITERALS))
@@ -257,39 +258,40 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const int nSt
nStartingMatchLen = nMinMatchSize;
for (k = nStartingMatchLen; k <= nMatchLen; k++) {
int nMatchLenCost = lzsa_get_match_varlen_size_v2(k - MIN_MATCH_SIZE_V2);
lzsa_arrival *pDestSlots = &arrival[(i + k) << MATCHES_PER_OFFSET_SHIFT];
for (j = 0; j < NMATCHES_PER_OFFSET && arrival[(i << MATCHES_PER_OFFSET_SHIFT) + j].from_slot; j++) {
int nMatchOffsetCost = (match[m].offset == arrival[(i << MATCHES_PER_OFFSET_SHIFT) + j].rep_offset) ? 0 : nNoRe_matchOffsetCost;
int nMatchOffsetCost = (nMatchOffset == arrival[(i << MATCHES_PER_OFFSET_SHIFT) + j].rep_offset) ? 0 : nNoRepmatchOffsetCost;
int nPrevCost = arrival[(i << MATCHES_PER_OFFSET_SHIFT) + j].cost;
int nCodingChoiceCost = nPrevCost + 8 /* token */ /* the actual cost of the literals themselves accumulates up the chain */ + nMatchOffsetCost + nMatchLenCost;
int exists = 0;
for (n = 0;
n < NMATCHES_PER_OFFSET && arrival[((i + k) << MATCHES_PER_OFFSET_SHIFT) + n].from_slot && arrival[((i + k) << MATCHES_PER_OFFSET_SHIFT) + n].cost <= nCodingChoiceCost;
n < NMATCHES_PER_OFFSET && pDestSlots[n].from_slot && pDestSlots[n].cost <= nCodingChoiceCost;
n++) {
if (arrival[((i + k) << MATCHES_PER_OFFSET_SHIFT) + n].rep_offset == match[m].offset) {
if (pDestSlots[n].rep_offset == nMatchOffset) {
exists = 1;
break;
}
}
for (n = 0; !exists && n < NMATCHES_PER_OFFSET; n++) {
lzsa_arrival *pDestArrival = &arrival[((i + k) << MATCHES_PER_OFFSET_SHIFT) + n];
lzsa_arrival *pDestArrival = &pDestSlots[n];
if (pDestArrival->from_slot == 0 ||
nCodingChoiceCost <= pDestArrival->cost) {
memmove(&arrival[((i + k) << MATCHES_PER_OFFSET_SHIFT) + n + 1],
&arrival[((i + k) << MATCHES_PER_OFFSET_SHIFT) + n],
memmove(&pDestSlots[n + 1],
&pDestSlots[n],
sizeof(lzsa_arrival) * (NMATCHES_PER_OFFSET - n - 1));
pDestArrival->cost = nCodingChoiceCost;
pDestArrival->from_pos = i;
pDestArrival->from_slot = j + 1;
pDestArrival->match_offset = match[m].offset;
pDestArrival->match_offset = nMatchOffset;
pDestArrival->match_len = k;
pDestArrival->num_literals = 0;
pDestArrival->rep_offset = match[m].offset;
pDestArrival->rep_offset = nMatchOffset;
break;
}
}