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Add more missing constants; more minor cleanup

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Emmanuel Marty 2022-10-16 18:39:24 +02:00 committed by GitHub
parent 34ed06abfb
commit 5484395465
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2 changed files with 9 additions and 13 deletions
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6
src/shrink_block_v1.c
View File

@ -289,7 +289,7 @@ static void lzsa_optimize_forward_v1(lzsa_compressor *pCompressor, lzsa_match *p
} }
} }
const lzsa_arrival *end_arrival = &arrival[(i << ARRIVALS_PER_POSITION_SHIFT_V1) + 0]; const lzsa_arrival *end_arrival = &arrival[i << ARRIVALS_PER_POSITION_SHIFT_V1];
while (end_arrival->from_slot > 0 && end_arrival->from_pos >= 0 && (end_arrival->from_pos + nStartOffset) < nEndOffset) { while (end_arrival->from_slot > 0 && end_arrival->from_pos >= 0 && (end_arrival->from_pos + nStartOffset) < nEndOffset) {
pBestMatch[end_arrival->from_pos + nStartOffset].length = end_arrival->match_len; pBestMatch[end_arrival->from_pos + nStartOffset].length = end_arrival->match_len;
@ -419,7 +419,7 @@ static int lzsa_optimize_command_count_v1(lzsa_compressor *pCompressor, const un
* *
* @return size of compressed data that will be written to output buffer * @return size of compressed data that will be written to output buffer
*/ */
static int lzsa_get_compressed_size_v1(lzsa_compressor *pCompressor, lzsa_match *pBestMatch, const int nStartOffset, const int nEndOffset) { static int lzsa_get_compressed_size_v1(lzsa_compressor *pCompressor, const lzsa_match *pBestMatch, const int nStartOffset, const int nEndOffset) {
int i; int i;
int nNumLiterals = 0; int nNumLiterals = 0;
int nCompressedSize = 0; int nCompressedSize = 0;
@ -470,7 +470,7 @@ static int lzsa_get_compressed_size_v1(lzsa_compressor *pCompressor, lzsa_match
* *
* @return size of compressed data in output buffer, or -1 if the data is uncompressible * @return size of compressed data in output buffer, or -1 if the data is uncompressible
*/ */
static int lzsa_write_block_v1(lzsa_compressor *pCompressor, lzsa_match *pBestMatch, const unsigned char *pInWindow, const int nStartOffset, const int nEndOffset, unsigned char *pOutData, const int nMaxOutDataSize) { static int lzsa_write_block_v1(lzsa_compressor *pCompressor, const lzsa_match *pBestMatch, const unsigned char *pInWindow, const int nStartOffset, const int nEndOffset, unsigned char *pOutData, const int nMaxOutDataSize) {
int i; int i;
int nNumLiterals = 0; int nNumLiterals = 0;
int nInFirstLiteralOffset = 0; int nInFirstLiteralOffset = 0;

16
src/shrink_block_v2.c
View File

@ -482,9 +482,7 @@ static void lzsa_optimize_forward_v2(lzsa_compressor *pCompressor, const unsigne
int nNonRepMatchArrivalIdx = -1; int nNonRepMatchArrivalIdx = -1;
for (j = 0; j < nNumArrivalsForThisPos; j++) { for (j = 0; j < nNumArrivalsForThisPos; j++) {
const int nRepOffset = cur_arrival[j].rep_offset; if (nMatchOffset != cur_arrival[j].rep_offset) {
if (nMatchOffset != nRepOffset) {
const int nPrevCost = cur_arrival[j].cost; const int nPrevCost = cur_arrival[j].cost;
const int nScorePenalty = 3 + (match[m].length >> 15); const int nScorePenalty = 3 + (match[m].length >> 15);
@ -768,15 +766,15 @@ static int lzsa_optimize_command_count_v2(lzsa_compressor *pCompressor, const un
if (nNextIndex < nEndOffset && pBestMatch[nNextIndex].length >= MIN_MATCH_SIZE_V2) { if (nNextIndex < nEndOffset && pBestMatch[nNextIndex].length >= MIN_MATCH_SIZE_V2) {
/* This command is a match, is followed by 'nNextLiterals' literals and then by another match */ /* This command is a match, is followed by 'nNextLiterals' literals and then by another match */
if (nRepMatchOffset && pMatch->offset != nRepMatchOffset && (pBestMatch[nNextIndex].offset != pMatch->offset || pBestMatch[nNextIndex].offset == nRepMatchOffset || if (nRepMatchOffset && pMatch->offset != nRepMatchOffset && (pBestMatch[nNextIndex].offset != pMatch->offset ||
((pMatch->offset <= 32) ? 4 : ((pMatch->offset <= 512) ? 8 : ((pMatch->offset <= (8192 + 512)) ? 12 : 16))) > ((pMatch->offset <= 32) ? 4 : ((pMatch->offset <= 512) ? 8 : ((pMatch->offset <= (8192 + 512)) ? 12 : 16))) >
((pBestMatch[nNextIndex].offset <= 32) ? 4 : ((pBestMatch[nNextIndex].offset <= 512) ? 8 : ((pBestMatch[nNextIndex].offset <= (8192 + 512)) ? 12 : 16))))) { ((pBestMatch[nNextIndex].offset <= 32) ? 4 : ((pBestMatch[nNextIndex].offset <= 512) ? 8 : ((pBestMatch[nNextIndex].offset <= (8192 + 512)) ? 12 : 16))))) {
/* Check if we can change the current match's offset to be the same as the previous match's offset, and get an extra repmatch. This will occur when /* Check if we can change the current match's offset to be the same as the previous match's offset, and get an extra repmatch. This will occur when
* matching large regions of identical bytes for instance, where there are too many offsets to be considered by the parser, and when not compressing to favor the * matching large regions of identical bytes for instance, where there are too many offsets to be considered by the parser, and when not compressing to favor the
* ratio (the forward arrivals parser already has this covered). */ * ratio (the forward arrivals parser already has this covered). */
if (i >= nRepMatchOffset && if (i >= nRepMatchOffset &&
(i - nRepMatchOffset + pMatch->length) <= nEndOffset && (i + pMatch->length) <= nEndOffset &&
!memcmp(pInWindow + i - nRepMatchOffset, pInWindow + i - pMatch->offset, pMatch->length)) { !memcmp(pInWindow + i - nRepMatchOffset, pInWindow + i, pMatch->length)) {
pMatch->offset = nRepMatchOffset; pMatch->offset = nRepMatchOffset;
nDidReduce = 1; nDidReduce = 1;
} }
@ -784,14 +782,12 @@ static int lzsa_optimize_command_count_v2(lzsa_compressor *pCompressor, const un
if (pBestMatch[nNextIndex].offset && pMatch->offset != pBestMatch[nNextIndex].offset && nRepMatchOffset != pBestMatch[nNextIndex].offset) { if (pBestMatch[nNextIndex].offset && pMatch->offset != pBestMatch[nNextIndex].offset && nRepMatchOffset != pBestMatch[nNextIndex].offset) {
/* Otherwise, try to gain a match forward as well */ /* Otherwise, try to gain a match forward as well */
if (i >= pBestMatch[nNextIndex].offset && (i - pBestMatch[nNextIndex].offset + pMatch->length) <= nEndOffset) { if (i >= pBestMatch[nNextIndex].offset && (i + pMatch->length) <= nEndOffset) {
int nMaxLen = 0; int nMaxLen = 0;
const unsigned char *pInWindowAtPos = pInWindow + i; const unsigned char *pInWindowAtPos = pInWindow + i;
while ((nMaxLen + 8) < pMatch->length && !memcmp(pInWindowAtPos + nMaxLen - pBestMatch[nNextIndex].offset, pInWindowAtPos + nMaxLen, 8))
nMaxLen += 8;
while ((nMaxLen + 4) < pMatch->length && !memcmp(pInWindowAtPos + nMaxLen - pBestMatch[nNextIndex].offset, pInWindowAtPos + nMaxLen, 4)) while ((nMaxLen + 4) < pMatch->length && !memcmp(pInWindowAtPos + nMaxLen - pBestMatch[nNextIndex].offset, pInWindowAtPos + nMaxLen, 4))
nMaxLen += 4; nMaxLen += 4;
while (nMaxLen < pMatch->length && pInWindowAtPos[nMaxLen - pBestMatch[nNextIndex].offset] == pInWindowAtPos[nMaxLen - pMatch->offset]) while (nMaxLen < pMatch->length && pInWindowAtPos[nMaxLen - pBestMatch[nNextIndex].offset] == pInWindowAtPos[nMaxLen])
nMaxLen++; nMaxLen++;
if (nMaxLen >= pMatch->length) { if (nMaxLen >= pMatch->length) {
/* Replace */ /* Replace */