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Merge pull request #848 from terrelln/fparams

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[block] Don't use fParams in ZSTD_decompressBlock()
This commit is contained in:
Yann Collet 2017-09-18 13:48:31 -07:00 committed by GitHub
commit 72a80515ec
1 changed files with 36 additions and 18 deletions
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50
lib/decompress/zstd_decompress.c
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@ -860,7 +860,10 @@ size_t ZSTD_execSequenceLast7(BYTE* op,
} }
static seq_t ZSTD_decodeSequence(seqState_t* seqState) typedef enum { ZSTD_lo_isRegularOffset, ZSTD_lo_isLongOffset=1 } ZSTD_longOffset_e;
static seq_t ZSTD_decodeSequence(seqState_t* seqState, const ZSTD_longOffset_e longOffsets)
{ {
seq_t seq; seq_t seq;
@ -900,9 +903,17 @@ static seq_t ZSTD_decodeSequence(seqState_t* seqState)
if (!ofCode) if (!ofCode)
offset = 0; offset = 0;
else { else {
ZSTD_STATIC_ASSERT(ZSTD_lo_isLongOffset == 1);
if (longOffsets) {
int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN);
offset = OF_base[ofCode] + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits);
if (MEM_32bits() || extraBits) BIT_reloadDStream(&seqState->DStream);
if (extraBits) offset += BIT_readBitsFast(&seqState->DStream, extraBits);
} else {
offset = OF_base[ofCode] + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */ offset = OF_base[ofCode] + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */
if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream);
} }
}
if (ofCode <= 1) { if (ofCode <= 1) {
offset += (llCode==0); offset += (llCode==0);
@ -1030,7 +1041,8 @@ size_t ZSTD_execSequence(BYTE* op,
static size_t ZSTD_decompressSequences( static size_t ZSTD_decompressSequences(
ZSTD_DCtx* dctx, ZSTD_DCtx* dctx,
void* dst, size_t maxDstSize, void* dst, size_t maxDstSize,
const void* seqStart, size_t seqSize) const void* seqStart, size_t seqSize,
const ZSTD_longOffset_e isLongOffset)
{ {
const BYTE* ip = (const BYTE*)seqStart; const BYTE* ip = (const BYTE*)seqStart;
const BYTE* const iend = ip + seqSize; const BYTE* const iend = ip + seqSize;
@ -1065,7 +1077,7 @@ static size_t ZSTD_decompressSequences(
for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && nbSeq ; ) { for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && nbSeq ; ) {
nbSeq--; nbSeq--;
{ seq_t const sequence = ZSTD_decodeSequence(&seqState); { seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset);
size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, base, vBase, dictEnd); size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, base, vBase, dictEnd);
DEBUGLOG(6, "regenerated sequence size : %u", (U32)oneSeqSize); DEBUGLOG(6, "regenerated sequence size : %u", (U32)oneSeqSize);
if (ZSTD_isError(oneSeqSize)) return oneSeqSize; if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
@ -1090,7 +1102,6 @@ static size_t ZSTD_decompressSequences(
} }
typedef enum { ZSTD_lo_isRegularOffset, ZSTD_lo_isLongOffset=1 } ZSTD_longOffset_e;
HINT_INLINE HINT_INLINE
seq_t ZSTD_decodeSequenceLong(seqState_t* seqState, ZSTD_longOffset_e const longOffsets) seq_t ZSTD_decodeSequenceLong(seqState_t* seqState, ZSTD_longOffset_e const longOffsets)
@ -1133,6 +1144,7 @@ seq_t ZSTD_decodeSequenceLong(seqState_t* seqState, ZSTD_longOffset_e const long
if (!ofCode) if (!ofCode)
offset = 0; offset = 0;
else { else {
ZSTD_STATIC_ASSERT(ZSTD_lo_isLongOffset == 1);
if (longOffsets) { if (longOffsets) {
int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN); int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN);
offset = OF_base[ofCode] + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits); offset = OF_base[ofCode] + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits);
@ -1268,7 +1280,8 @@ size_t ZSTD_execSequenceLong(BYTE* op,
static size_t ZSTD_decompressSequencesLong( static size_t ZSTD_decompressSequencesLong(
ZSTD_DCtx* dctx, ZSTD_DCtx* dctx,
void* dst, size_t maxDstSize, void* dst, size_t maxDstSize,
const void* seqStart, size_t seqSize) const void* seqStart, size_t seqSize,
const ZSTD_longOffset_e isLongOffset)
{ {
const BYTE* ip = (const BYTE*)seqStart; const BYTE* ip = (const BYTE*)seqStart;
const BYTE* const iend = ip + seqSize; const BYTE* const iend = ip + seqSize;
@ -1282,10 +1295,6 @@ static size_t ZSTD_decompressSequencesLong(
const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd); const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd);
int nbSeq; int nbSeq;
unsigned long long const regularWindowSizeMax = 1ULL << STREAM_ACCUMULATOR_MIN;
ZSTD_longOffset_e const isLongOffset = (ZSTD_longOffset_e)(MEM_32bits() && (dctx->fParams.windowSize >= regularWindowSizeMax));
ZSTD_STATIC_ASSERT(ZSTD_lo_isLongOffset == 1);
/* Build Decoding Tables */ /* Build Decoding Tables */
{ size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize); { size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize);
if (ZSTD_isError(seqHSize)) return seqHSize; if (ZSTD_isError(seqHSize)) return seqHSize;
@ -1353,9 +1362,18 @@ static size_t ZSTD_decompressSequencesLong(
static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx, static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
void* dst, size_t dstCapacity, void* dst, size_t dstCapacity,
const void* src, size_t srcSize) const void* src, size_t srcSize, const int frame)
{ /* blockType == blockCompressed */ { /* blockType == blockCompressed */
const BYTE* ip = (const BYTE*)src; const BYTE* ip = (const BYTE*)src;
/* isLongOffset must be true if there are long offsets.
* Offsets are long if they are larger than 2^STREAM_ACCUMULATOR_MIN.
* We don't expect that to be the case in 64-bit mode.
* If we are in block mode we don't know the window size, so we have to be
* conservative.
*/
ZSTD_longOffset_e const isLongOffset = (ZSTD_longOffset_e)(MEM_32bits() && (!frame || dctx->fParams.windowSize > (1ULL << STREAM_ACCUMULATOR_MIN)));
/* We don't expect window sizes this big. */
assert(!frame || dctx->fParams.windowSize <= (1ULL << STREAM_ACCUMULATOR_MIN_64));
DEBUGLOG(5, "ZSTD_decompressBlock_internal"); DEBUGLOG(5, "ZSTD_decompressBlock_internal");
if (srcSize >= ZSTD_BLOCKSIZE_MAX) return ERROR(srcSize_wrong); if (srcSize >= ZSTD_BLOCKSIZE_MAX) return ERROR(srcSize_wrong);
@ -1367,9 +1385,9 @@ static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx,
ip += litCSize; ip += litCSize;
srcSize -= litCSize; srcSize -= litCSize;
} }
if (dctx->fParams.windowSize > (1<<23)) if (frame && dctx->fParams.windowSize > (1<<23))
return ZSTD_decompressSequencesLong(dctx, dst, dstCapacity, ip, srcSize); return ZSTD_decompressSequencesLong(dctx, dst, dstCapacity, ip, srcSize, isLongOffset);
return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize); return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize, isLongOffset);
} }
@ -1389,7 +1407,7 @@ size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx,
{ {
size_t dSize; size_t dSize;
ZSTD_checkContinuity(dctx, dst); ZSTD_checkContinuity(dctx, dst);
dSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize); dSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize, /* frame */ 0);
dctx->previousDstEnd = (char*)dst + dSize; dctx->previousDstEnd = (char*)dst + dSize;
return dSize; return dSize;
} }
@ -1505,7 +1523,7 @@ static size_t ZSTD_decompressFrame(ZSTD_DCtx* dctx,
switch(blockProperties.blockType) switch(blockProperties.blockType)
{ {
case bt_compressed: case bt_compressed:
decodedSize = ZSTD_decompressBlock_internal(dctx, op, oend-op, ip, cBlockSize); decodedSize = ZSTD_decompressBlock_internal(dctx, op, oend-op, ip, cBlockSize, /* frame */ 1);
break; break;
case bt_raw : case bt_raw :
decodedSize = ZSTD_copyRawBlock(op, oend-op, ip, cBlockSize); decodedSize = ZSTD_copyRawBlock(op, oend-op, ip, cBlockSize);
@ -1759,7 +1777,7 @@ size_t ZSTD_decompressContinue(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, c
{ {
case bt_compressed: case bt_compressed:
DEBUGLOG(5, "case bt_compressed"); DEBUGLOG(5, "case bt_compressed");
rSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize); rSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize, /* frame */ 1);
break; break;
case bt_raw : case bt_raw :
rSize = ZSTD_copyRawBlock(dst, dstCapacity, src, srcSize); rSize = ZSTD_copyRawBlock(dst, dstCapacity, src, srcSize);