Speed up LZSA2 compression

This commit is contained in:
Emmanuel Marty 2019-10-09 16:07:29 +02:00 committed by GitHub
parent b09dadb1c1
commit 6ce846ff24
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23

View File

@ -192,13 +192,17 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
memset(arrival + (nStartOffset << MATCHES_PER_OFFSET_SHIFT), 0, sizeof(lzsa_arrival) * ((nEndOffset - nStartOffset) << MATCHES_PER_OFFSET_SHIFT));
for (i = (nStartOffset << MATCHES_PER_OFFSET_SHIFT); i != (nEndOffset << MATCHES_PER_OFFSET_SHIFT) - 1; i++) {
arrival[i].cost = 0x40000000;
}
arrival[nStartOffset << MATCHES_PER_OFFSET_SHIFT].from_slot = -1;
for (i = nStartOffset; i != (nEndOffset - 1); i++) {
int m, nMatches;
for (j = 0; j < NMATCHES_PER_OFFSET && arrival[(i << MATCHES_PER_OFFSET_SHIFT) + j].from_slot; j++) {
int nPrevCost = arrival[(i << MATCHES_PER_OFFSET_SHIFT) + j].cost;
const int nPrevCost = arrival[(i << MATCHES_PER_OFFSET_SHIFT) + j].cost & 0x3fffffff;
int nCodingChoiceCost = nPrevCost + 8 /* literal */;
int nNumLiterals = arrival[(i << MATCHES_PER_OFFSET_SHIFT) + j].num_literals + 1;
@ -215,25 +219,25 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
if (!nFavorRatio && nNumLiterals == 1)
nCodingChoiceCost += MODESWITCH_PENALTY;
if (arrival[((i + 1) << MATCHES_PER_OFFSET_SHIFT) + NMATCHES_PER_OFFSET - 1].from_slot == 0 || nCodingChoiceCost <= arrival[((i + 1) << MATCHES_PER_OFFSET_SHIFT) + NMATCHES_PER_OFFSET - 1].cost) {
lzsa_arrival *pDestSlots = &arrival[(i + 1) << MATCHES_PER_OFFSET_SHIFT];
if (pDestSlots[NMATCHES_PER_OFFSET - 1].from_slot == 0 || nCodingChoiceCost <= pDestSlots[NMATCHES_PER_OFFSET - 1].cost) {
int exists = 0;
for (n = 0;
n < NMATCHES_PER_OFFSET && arrival[((i + 1) << MATCHES_PER_OFFSET_SHIFT) + n].from_slot && arrival[((i + 1) << MATCHES_PER_OFFSET_SHIFT) + n].cost <= nCodingChoiceCost;
n < NMATCHES_PER_OFFSET && pDestSlots[n].cost <= nCodingChoiceCost;
n++) {
if (arrival[((i + 1) << MATCHES_PER_OFFSET_SHIFT) + n].rep_offset == arrival[(i << MATCHES_PER_OFFSET_SHIFT) + j].rep_offset) {
if (pDestSlots[n].rep_offset == arrival[(i << MATCHES_PER_OFFSET_SHIFT) + j].rep_offset) {
exists = 1;
break;
}
}
for (n = 0; !exists && n < NMATCHES_PER_OFFSET; n++) {
lzsa_arrival *pDestArrival = &arrival[((i + 1) << MATCHES_PER_OFFSET_SHIFT) + n];
if (pDestArrival->from_slot == 0 ||
nCodingChoiceCost <= pDestArrival->cost) {
lzsa_arrival *pDestArrival = &pDestSlots[n];
if (nCodingChoiceCost <= pDestArrival->cost) {
if (pDestArrival->from_slot) {
memmove(&arrival[((i + 1) << MATCHES_PER_OFFSET_SHIFT) + n + 1],
&arrival[((i + 1) << MATCHES_PER_OFFSET_SHIFT) + n],
memmove(&pDestSlots[n + 1],
&pDestSlots[n],
sizeof(lzsa_arrival) * (NMATCHES_PER_OFFSET - n - 1));
}
@ -289,7 +293,7 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
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++) {
const int nPrevCost = arrival[(i << MATCHES_PER_OFFSET_SHIFT) + j].cost;
const int nPrevCost = arrival[(i << MATCHES_PER_OFFSET_SHIFT) + j].cost & 0x3fffffff;
int nRepOffset = arrival[(i << MATCHES_PER_OFFSET_SHIFT) + j].rep_offset;
int nMatchOffsetCost = (nMatchOffset == nRepOffset) ? 0 : nNoRepmatchOffsetCost;
@ -304,7 +308,7 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
int exists = 0;
for (n = 0;
n < NMATCHES_PER_OFFSET && pDestSlots[n].from_slot && pDestSlots[n].cost <= nCodingChoiceCost;
n < NMATCHES_PER_OFFSET && pDestSlots[n].cost <= nCodingChoiceCost;
n++) {
if (pDestSlots[n].rep_offset == nMatchOffset) {
exists = 1;
@ -316,9 +320,7 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
for (n = 0; n < NMATCHES_PER_OFFSET; n++) {
lzsa_arrival *pDestArrival = &pDestSlots[n];
if (pDestArrival->from_slot == 0 ||
nCodingChoiceCost <= pDestArrival->cost) {
if (nCodingChoiceCost <= pDestArrival->cost) {
if (pDestArrival->from_slot) {
memmove(&pDestSlots[n + 1],
&pDestSlots[n],
@ -348,7 +350,7 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
/* A match is possible at the rep offset; insert the extra coding choice. */
for (n = 0;
n < NMATCHES_PER_OFFSET && pDestSlots[n].from_slot && pDestSlots[n].cost <= nRepCodingChoiceCost;
n < NMATCHES_PER_OFFSET && pDestSlots[n].cost <= nRepCodingChoiceCost;
n++) {
if (pDestSlots[n].rep_offset == nRepOffset) {
exists = 1;
@ -360,9 +362,7 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
for (n = 0; n < NMATCHES_PER_OFFSET; n++) {
lzsa_arrival *pDestArrival = &pDestSlots[n];
if (pDestArrival->from_slot == 0 ||
nRepCodingChoiceCost <= pDestArrival->cost) {
if (nRepCodingChoiceCost <= pDestArrival->cost) {
if (pDestArrival->from_slot) {
memmove(&pDestSlots[n + 1],
&pDestSlots[n],