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Manually moving instead of memcpy on decoder and using genBuffer()

dev
Bimba Shrestha 2019-10-03 09:26:51 -07:00
parent 61ec4c2e7f
commit 36528b96c4
2 changed files with 41 additions and 31 deletions
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59
lib/compress/zstd_compress.c
View File

@ -2272,37 +2272,46 @@ static void ZSTD_copyBlockSequences(ZSTD_CCtx* zc)
size_t seqsSize = seqStore->sequences - seqs;
ZSTD_Sequence* outSeqs = &zc->seqCollector.seqStart[zc->seqCollector.seqIndex];
int i;
size_t i; size_t position; int repIdx;
assert(zc->seqCollector.seqIndex + 1 < zc->seqCollector.maxSequences);
for (i = 0; i < (int)seqsSize; ++i) {
unsigned int offsetValue = seqs[i].offset;
for (i = 0, position = 0; i < seqsSize; ++i) {
outSeqs[i].offset = seqs[i].offset;
outSeqs[i].litLength = seqs[i].litLength;
outSeqs[i].matchLength = seqs[i].matchLength;
if (offsetValue > 3) {
outSeqs[i].offset = offsetValue - 3;
} else {
/* special repeat offset case */
unsigned int repeatOffset1 = i - 1 >= 0 ? outSeqs[i - 1].offset : 1;
unsigned int repeatOffset2 = 1 - 2 >= 0 ? outSeqs[i - 2].offset : 4;
unsigned int repeatOffset3 = i - 3 >= 0 ? outSeqs[i - 3].offset : 8;
if (seqs[i].litLength != 0) {
switch (offsetValue) {
case 1: outSeqs[i].offset = repeatOffset1; break;
case 2: outSeqs[i].offset = repeatOffset2; break;
case 3: outSeqs[i].offset = repeatOffset3; break;
}
} else {
/* offsets shifted by one */
switch (offsetValue) {
case 1: outSeqs[i].offset = repeatOffset2; break;
case 2: outSeqs[i].offset = repeatOffset3; break;
/* corner case where offsetValue == 3 */
case 3: outSeqs[i].offset = repeatOffset1 - 1; break;
}
outSeqs[i].matchLength = seqs[i].matchLength + MINMATCH;
if (i == seqStore->longLengthPos) {
if (seqStore->longLengthID == 1) {
outSeqs[i].litLength += 0x10000;
} else if (seqStore->longLengthID == 2) {
outSeqs[i].matchLength += 0x10000;
}
}
if (outSeqs[i].offset <= ZSTD_REP_NUM) {
outSeqs[i].rep = outSeqs[i].offset;
repIdx = (unsigned int)i - outSeqs[i].offset;
if (outSeqs[i].litLength == 0) {
if (outSeqs[i].offset < 3) {
--repIdx;
} else {
repIdx = (unsigned int)i - 1;
}
++outSeqs[i].rep;
}
assert(repIdx >= -3);
outSeqs[i].offset = repIdx >= 0 ? outSeqs[repIdx].offset : repStartValue[-repIdx - 1];
if (outSeqs[i].rep == 4) {
--outSeqs[i].offset;
}
} else {
outSeqs[i].offset -= ZSTD_REP_NUM;
}
position += outSeqs[i].litLength;
outSeqs[i].matchPos = (unsigned int)position;
position += outSeqs[i].matchLength;
}
zc->seqCollector.seqIndex += seqsSize;
}

13
tests/fuzzer.c
View File

@ -307,7 +307,8 @@ static int FUZ_mallocTests(unsigned seed, double compressibility, unsigned part)
static void FUZ_decodeSequences(BYTE* dst, ZSTD_Sequence* seqs, size_t seqsSize, BYTE* src, size_t size)
{
size_t i;
for(i = 0; i < seqsSize; ++i) {
size_t j;
for(i = 0; i < seqsSize - 1; ++i) {
assert(dst + seqs[i].litLength + seqs[i].matchLength < dst + size);
assert(src + seqs[i].litLength + seqs[i].matchLength < src + size);
@ -316,7 +317,8 @@ static void FUZ_decodeSequences(BYTE* dst, ZSTD_Sequence* seqs, size_t seqsSize,
src += seqs[i].litLength;
size -= seqs[i].litLength;
memcpy(dst, dst-seqs[i].offset, seqs[i].matchLength);
for (j = 0; j < seqs[i].matchLength; ++j)
dst[j] = dst[j - seqs[i].offset];
dst += seqs[i].matchLength;
src += seqs[i].matchLength;
size -= seqs[i].matchLength;
@ -1982,20 +1984,19 @@ static int basicUnitTests(U32 const seed, double compressibility)
DISPLAYLEVEL(3, "test%3i : ZSTD_getSequences decode from sequences test : ", testNb++);
{
size_t srcSize = sizeof(U32) * 1000;
size_t srcSize = 100 KB;
BYTE* src = (BYTE*)CNBuffer;
BYTE* decoded = (BYTE*)compressedBuffer;
ZSTD_CCtx* cctx = ZSTD_createCCtx();
ZSTD_Sequence* seqs = (ZSTD_Sequence*)malloc(srcSize * sizeof(ZSTD_Sequence));
size_t seqsSize; size_t i;
U32 randSeed = seed;
size_t seqsSize;
if (seqs == NULL) goto _output_error;
assert(cctx != NULL);
/* Populate src with random data */
for (i = 0; i < srcSize / sizeof(U32); ++i) {((U32*)CNBuffer)[i] = FUZ_rand(&randSeed);}
RDG_genBuffer(CNBuffer, srcSize, compressibility, 0., seed);
/* get the sequences */
seqsSize = ZSTD_getSequences(cctx, seqs, srcSize, src, srcSize);