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re-inserted offset evaluation

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This commit is contained in:
Yann Collet
2018-03-05 13:08:59 -08:00
parent b91ddf0ae6
commit cb789d2df8
2 changed files with 34 additions and 38 deletions
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lib/decompress/zstd_decompress.c
+32 -20
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@@ -1248,47 +1248,49 @@ typedef enum { ZSTD_lo_isRegularOffset, ZSTD_lo_isLongOffset=1 } ZSTD_longOffset
#endif
typedef size_t (*ZSTD_decompressSequences_t)(
ZSTD_DCtx *dctx, void *dst, size_t maxDstSize, const void *seqStart,
size_t seqSize, const ZSTD_longOffset_e isLongOffset);
ZSTD_DCtx *dctx, void *dst, size_t maxDstSize,
const void *seqStart, size_t seqSize, int nbSeq,
const ZSTD_longOffset_e isLongOffset);
static size_t ZSTD_decompressSequences(ZSTD_DCtx* dctx, void* dst, size_t maxDstSize,
const void* seqStart, size_t seqSize,
const void* seqStart, size_t seqSize, int nbSeq,
const ZSTD_longOffset_e isLongOffset)
{
#if DYNAMIC_BMI2
if (dctx->bmi2) {
return ZSTD_decompressSequences_bmi2(dctx, dst, maxDstSize, seqStart, seqSize, isLongOffset);
return ZSTD_decompressSequences_bmi2(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset);
}
#endif
return ZSTD_decompressSequences_default(dctx, dst, maxDstSize, seqStart, seqSize, isLongOffset);
return ZSTD_decompressSequences_default(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset);
}
static size_t ZSTD_decompressSequencesLong(ZSTD_DCtx* dctx, void* dst, size_t maxDstSize,
const void* seqStart, size_t seqSize,
const ZSTD_longOffset_e isLongOffset)
static size_t ZSTD_decompressSequencesLong(ZSTD_DCtx* dctx,
void* dst, size_t maxDstSize,
const void* seqStart, size_t seqSize, int nbSeq,
const ZSTD_longOffset_e isLongOffset)
{
#if DYNAMIC_BMI2
if (dctx->bmi2) {
return ZSTD_decompressSequencesLong_bmi2(dctx, dst, maxDstSize, seqStart, seqSize, isLongOffset);
return ZSTD_decompressSequencesLong_bmi2(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset);
}
#endif
return ZSTD_decompressSequencesLong_default(dctx, dst, maxDstSize, seqStart, seqSize, isLongOffset);
return ZSTD_decompressSequencesLong_default(dctx, dst, maxDstSize, seqStart, seqSize, nbSeq, isLongOffset);
}
static unsigned
ZSTD_getLongOffsetsShare(const FSE_DTable* offTable)
ZSTD_getLongOffsetsShare(const ZSTD_seqSymbol* offTable)
{
const void* ptr = offTable;
U32 const tableLog = ((const FSE_DTableHeader*)ptr)[0].tableLog;
const FSE_decode_t* table = ((const FSE_decode_t*)ptr) + 1;
const ZSTD_seqSymbol* table = offTable + 1;
U32 const max = 1 << tableLog;
U32 u, total = 0;
assert(tableLog <= OffFSELog);
for (u=0; u<max; u++)
if (table[u].symbol > 23) total += 1;
if (table[u].nbAdditionalBits > 23) total += 1;
total <<= (OffFSELog - tableLog);
assert(tableLog <= OffFSELog);
total <<= (OffFSELog - tableLog); /* scale to OffFSELog */
return total;
}
@@ -1317,12 +1319,22 @@ static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
srcSize -= litCSize;
}
if ( frame /* windowSize exists */
&& (dctx->fParams.windowSize > (1<<24))
&& MEM_64bits() /* x86 benefits less from long mode than x64 */ )
return ZSTD_decompressSequencesLong(dctx, dst, dstCapacity, ip, srcSize, isLongOffset);
/* Build Decoding Tables */
{ int nbSeq;
size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, srcSize);
if (ZSTD_isError(seqHSize)) return seqHSize;
ip += seqHSize;
srcSize -= seqHSize;
return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize, isLongOffset);
if (dctx->fParams.windowSize > (1<<24)) {
U32 const shareLongOffsets = ZSTD_getLongOffsetsShare(dctx->OFTptr);
U32 const minShare = MEM_64bits() ? 5 : 13;
if (shareLongOffsets >= minShare)
return ZSTD_decompressSequencesLong(dctx, dst, dstCapacity, ip, srcSize, nbSeq, isLongOffset);
}
return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize, nbSeq, isLongOffset);
}
}