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Code Issues Releases 1 Activity

Add in proper block repcode histories

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This commit is contained in:
senhuang42 2020-11-12 14:37:47 -05:00
parent 06c7f14066
commit 674c9b9235
1 changed files with 7 additions and 8 deletions
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15
lib/compress/zstd_compress.c
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@ -2497,14 +2497,12 @@ static void ZSTD_copyBlockSequences(ZSTD_CCtx* zc)
ZSTD_Sequence* outSeqs = &zc->seqCollector.seqStart[zc->seqCollector.seqIndex];
size_t i;
U32 rep[ZSTD_REP_NUM];
U32* rep = zc->blockState.prevCBlock->rep;
U32 shouldUpdateRep;
assert(zc->seqCollector.seqIndex + 1 < zc->seqCollector.maxSequences);
/* Ensure we have enough space for last literals "sequence" */
assert(zc->seqCollector.maxSequences >= seqStoreSeqSize + 1);
ZSTD_memcpy(rep, zc->blockState.prevCBlock->rep, ZSTD_REP_NUM * sizeof(U32));
DEBUGLOG(2, "%u %u %u", rep[0], rep[1], rep[2]);
for (i = 0; i < seqStoreSeqSize; ++i) {
U32 rawOffset = seqStoreSeqs[i].offset - ZSTD_REP_NUM;
@ -2558,15 +2556,13 @@ static void ZSTD_copyBlockSequences(ZSTD_CCtx* zc)
}
outSeqs[i].offset = rawOffset;
if (shouldUpdateRep) {
int j;
for (j = ZSTD_REP_NUM - 1; j > 0; j--) {
rep[j] = rep[j - 1];
}
/* Purge the last repcode, move in new offset */
rep[2] = rep[1];
rep[1] = rep[0];
rep[0] = outSeqs[i].offset;
}
literalsRead += outSeqs[i].litLength;
}
/* Insert last literals (if any exist) in the block as a sequence with ml == off == 0.
* If there are no last literals, then we'll emit (of: 0, ml: 0, ll: 0), which is a marker
* for the block boundary, according to the API.
@ -2577,6 +2573,9 @@ static void ZSTD_copyBlockSequences(ZSTD_CCtx* zc)
outSeqs[i].matchLength = outSeqs[i].offset = outSeqs[i].rep = 0;
seqStoreSeqSize++;
zc->blockState.nextCBlock->rep[0] = zc->blockState.prevCBlock->rep[0];
zc->blockState.nextCBlock->rep[1] = zc->blockState.prevCBlock->rep[1];
zc->blockState.nextCBlock->rep[2] = zc->blockState.prevCBlock->rep[2];
zc->seqCollector.seqIndex += seqStoreSeqSize;
}