6502/lzsa
1
0
Fork 0
mirror of https://github.com/emmanuel-marty/lzsa.git synced 2024-12-29 16:29:16 +00:00
Code Issues Projects Releases Wiki Activity

Another small compression speedup

Browse Source
This commit is contained in:
Emmanuel Marty 2020-03-14 13:13:01 +01:00 committed by GitHub
parent 78276c18da
commit 236df36f2b
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 42 additions and 29 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

71
src/shrink_block_v2.c
View File

@ -431,7 +431,7 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
int nScore = arrival[(i << MATCHES_PER_ARRIVAL_SHIFT) + j].score + 3 + nScorePenalty;
for (n = 0;
n < nMatchesPerArrival && pDestSlots[n].cost <= nCodingChoiceCost;
n < nMatchesPerArrival && pDestSlots[n].cost < nCodingChoiceCost;
n++) {
if (pDestSlots[n].rep_offset == nMatchOffset &&
(!nInsertForwardReps || pDestSlots[n].cost != nCodingChoiceCost || pDestSlots[n].rep_pos >= i || nScore >= (pDestSlots[n].score + nDisableScore) ||
@ -442,39 +442,52 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
}
if (!exists) {
for (n = 0; n < nMatchesPerArrival - 1; n++) {
lzsa_arrival *pDestArrival = &pDestSlots[n];
for (int nn = n;
nn < nMatchesPerArrival && pDestSlots[nn].cost == nCodingChoiceCost;
nn++) {
if (pDestSlots[nn].rep_offset == nMatchOffset &&
(!nInsertForwardReps || pDestSlots[nn].cost != nCodingChoiceCost || pDestSlots[nn].rep_pos >= i || nScore >= (pDestSlots[nn].score + nDisableScore) ||
pDestSlots[nMatchesPerArrival - 1].from_slot)) {
exists = 1;
break;
}
}
if (nCodingChoiceCost < pDestArrival->cost ||
(nCodingChoiceCost == pDestArrival->cost && nScore < (pDestArrival->score + nDisableScore))) {
if (pDestArrival->from_slot) {
int z;
if (!exists) {
for (; n < nMatchesPerArrival - 1; n++) {
lzsa_arrival *pDestArrival = &pDestSlots[n];
for (z = n; z < nMatchesPerArrival - 1; z++) {
if (pDestSlots[z].rep_offset == nMatchOffset)
break;
if (nCodingChoiceCost < pDestArrival->cost ||
(nCodingChoiceCost == pDestArrival->cost && nScore < (pDestArrival->score + nDisableScore))) {
if (pDestArrival->from_slot) {
int z;
for (z = n; z < nMatchesPerArrival - 1; z++) {
if (pDestSlots[z].rep_offset == nMatchOffset)
break;
}
if (z == (nMatchesPerArrival - 1) && pDestSlots[z].from_slot && pDestSlots[z].match_len < MIN_MATCH_SIZE_V2)
z--;
memmove(&pDestSlots[n + 1],
&pDestSlots[n],
sizeof(lzsa_arrival) * (z - n));
}
if (z == (nMatchesPerArrival - 1) && pDestSlots[z].from_slot && pDestSlots[z].match_len < MIN_MATCH_SIZE_V2)
z--;
memmove(&pDestSlots[n + 1],
&pDestSlots[n],
sizeof(lzsa_arrival) * (z - n));
pDestArrival->cost = nCodingChoiceCost;
pDestArrival->from_pos = i;
pDestArrival->from_slot = j + 1;
pDestArrival->match_offset = nMatchOffset;
pDestArrival->match_len = k;
pDestArrival->num_literals = 0;
pDestArrival->score = nScore;
pDestArrival->rep_offset = nMatchOffset;
pDestArrival->rep_pos = i;
pDestArrival->rep_len = k;
nInsertedNoRepMatchCandidate = 1;
break;
}
pDestArrival->cost = nCodingChoiceCost;
pDestArrival->from_pos = i;
pDestArrival->from_slot = j + 1;
pDestArrival->match_offset = nMatchOffset;
pDestArrival->match_len = k;
pDestArrival->num_literals = 0;
pDestArrival->score = nScore;
pDestArrival->rep_offset = nMatchOffset;
pDestArrival->rep_pos = i;
pDestArrival->rep_len = k;
nInsertedNoRepMatchCandidate = 1;
break;
}
}
}