[libzstd] Refactor ZSTD_compressSequences()

dev
Nick Terrell 2017-07-14 19:11:58 -07:00
parent 830ef4152a
commit 634f012420
1 changed files with 166 additions and 144 deletions

View File

@ -1017,6 +1017,144 @@ void ZSTD_seqToCodes(const seqStore_t* seqStorePtr)
mlCodeTable[seqStorePtr->longLengthPos] = MaxML;
}
MEM_STATIC symbolEncodingType_e ZSTD_selectEncodingType(FSE_repeat* repeatMode,
size_t const mostFrequent, size_t nbSeq, U32 defaultNormLog)
{
#define MIN_SEQ_FOR_DYNAMIC_FSE 64
#define MAX_SEQ_FOR_STATIC_FSE 1000
if ((mostFrequent == nbSeq) && (nbSeq > 2)) {
*repeatMode = FSE_repeat_check;
return set_rle;
}
if ((*repeatMode == FSE_repeat_valid) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) {
return set_repeat;
}
if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (defaultNormLog-1)))) {
*repeatMode = FSE_repeat_valid;
return set_basic;
}
*repeatMode = FSE_repeat_check;
return set_compressed;
}
MEM_STATIC size_t ZSTD_buildCTable(void* dst, size_t dstCapacity,
FSE_CTable* CTable, U32 FSELog, symbolEncodingType_e type,
U32* count, U32 max,
BYTE const* codeTable, size_t nbSeq,
S16 const* defaultNorm, U32 defaultNormLog, U32 defaultMax,
void* workspace, size_t workspaceSize)
{
BYTE* op = (BYTE*)dst;
BYTE const* const oend = op + dstCapacity;
switch (type) {
case set_rle:
*op = codeTable[0];
CHECK_F(FSE_buildCTable_rle(CTable, (BYTE)max));
return 1;
case set_repeat:
return 0;
case set_basic:
CHECK_F(FSE_buildCTable_wksp(CTable, defaultNorm, defaultMax, defaultNormLog, workspace, workspaceSize));
return 0;
case set_compressed: {
S16 norm[MaxSeq + 1];
size_t nbSeq_1 = nbSeq;
const U32 tableLog = FSE_optimalTableLog(FSELog, nbSeq, max);
if (count[codeTable[nbSeq-1]] > 1) {
count[codeTable[nbSeq-1]]--;
nbSeq_1--;
}
CHECK_F(FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max));
{ size_t const NCountSize = FSE_writeNCount(op, oend - op, norm, max, tableLog); /* overflow protected */
if (FSE_isError(NCountSize)) return NCountSize;
CHECK_F(FSE_buildCTable_wksp(CTable, norm, max, tableLog, workspace, workspaceSize));
return NCountSize;
}
}
default: return assert(0), ERROR(GENERIC);
}
}
MEM_STATIC size_t ZSTD_encodeSequences(void* dst, size_t dstCapacity,
FSE_CTable const* CTable_MatchLength, BYTE const* mlCodeTable,
FSE_CTable const* CTable_OffsetBits, BYTE const* ofCodeTable,
FSE_CTable const* CTable_LitLength, BYTE const* llCodeTable,
seqDef const* sequences, size_t nbSeq, int longOffsets)
{
BIT_CStream_t blockStream;
FSE_CState_t stateMatchLength;
FSE_CState_t stateOffsetBits;
FSE_CState_t stateLitLength;
CHECK_E(BIT_initCStream(&blockStream, dst, dstCapacity), dstSize_tooSmall); /* not enough space remaining */
/* first symbols */
FSE_initCState2(&stateMatchLength, CTable_MatchLength, mlCodeTable[nbSeq-1]);
FSE_initCState2(&stateOffsetBits, CTable_OffsetBits, ofCodeTable[nbSeq-1]);
FSE_initCState2(&stateLitLength, CTable_LitLength, llCodeTable[nbSeq-1]);
BIT_addBits(&blockStream, sequences[nbSeq-1].litLength, LL_bits[llCodeTable[nbSeq-1]]);
if (MEM_32bits()) BIT_flushBits(&blockStream);
BIT_addBits(&blockStream, sequences[nbSeq-1].matchLength, ML_bits[mlCodeTable[nbSeq-1]]);
if (MEM_32bits()) BIT_flushBits(&blockStream);
if (longOffsets) {
U32 const ofBits = ofCodeTable[nbSeq-1];
int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN-1);
if (extraBits) {
BIT_addBits(&blockStream, sequences[nbSeq-1].offset, extraBits);
BIT_flushBits(&blockStream);
}
BIT_addBits(&blockStream, sequences[nbSeq-1].offset >> extraBits,
ofBits - extraBits);
} else {
BIT_addBits(&blockStream, sequences[nbSeq-1].offset, ofCodeTable[nbSeq-1]);
}
BIT_flushBits(&blockStream);
{ size_t n;
for (n=nbSeq-2 ; n<nbSeq ; n--) { /* intentional underflow */
BYTE const llCode = llCodeTable[n];
BYTE const ofCode = ofCodeTable[n];
BYTE const mlCode = mlCodeTable[n];
U32 const llBits = LL_bits[llCode];
U32 const ofBits = ofCode; /* 32b*/ /* 64b*/
U32 const mlBits = ML_bits[mlCode];
/* (7)*/ /* (7)*/
FSE_encodeSymbol(&blockStream, &stateOffsetBits, ofCode); /* 15 */ /* 15 */
FSE_encodeSymbol(&blockStream, &stateMatchLength, mlCode); /* 24 */ /* 24 */
if (MEM_32bits()) BIT_flushBits(&blockStream); /* (7)*/
FSE_encodeSymbol(&blockStream, &stateLitLength, llCode); /* 16 */ /* 33 */
if (MEM_32bits() || (ofBits+mlBits+llBits >= 64-7-(LLFSELog+MLFSELog+OffFSELog)))
BIT_flushBits(&blockStream); /* (7)*/
BIT_addBits(&blockStream, sequences[n].litLength, llBits);
if (MEM_32bits() && ((llBits+mlBits)>24)) BIT_flushBits(&blockStream);
BIT_addBits(&blockStream, sequences[n].matchLength, mlBits);
if (MEM_32bits()) BIT_flushBits(&blockStream); /* (7)*/
if (longOffsets) {
int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN-1);
if (extraBits) {
BIT_addBits(&blockStream, sequences[n].offset, extraBits);
BIT_flushBits(&blockStream); /* (7)*/
}
BIT_addBits(&blockStream, sequences[n].offset >> extraBits,
ofBits - extraBits); /* 31 */
} else {
BIT_addBits(&blockStream, sequences[n].offset, ofBits); /* 31 */
}
BIT_flushBits(&blockStream); /* (7)*/
} }
FSE_flushCState(&blockStream, &stateMatchLength);
FSE_flushCState(&blockStream, &stateOffsetBits);
FSE_flushCState(&blockStream, &stateLitLength);
{ size_t const streamSize = BIT_closeCStream(&blockStream);
if (streamSize==0) return ERROR(dstSize_tooSmall); /* not enough space */
return streamSize;
}
}
MEM_STATIC size_t ZSTD_compressSequences (ZSTD_CCtx* zc,
void* dst, size_t dstCapacity,
size_t srcSize)
@ -1024,7 +1162,6 @@ MEM_STATIC size_t ZSTD_compressSequences (ZSTD_CCtx* zc,
const int longOffsets = zc->appliedParams.cParams.windowLog > STREAM_ACCUMULATOR_MIN;
const seqStore_t* seqStorePtr = &(zc->seqStore);
U32 count[MaxSeq+1];
S16 norm[MaxSeq+1];
FSE_CTable* CTable_LitLength = zc->entropy->litlengthCTable;
FSE_CTable* CTable_OffsetBits = zc->entropy->offcodeCTable;
FSE_CTable* CTable_MatchLength = zc->entropy->matchlengthCTable;
@ -1038,7 +1175,8 @@ MEM_STATIC size_t ZSTD_compressSequences (ZSTD_CCtx* zc,
BYTE* op = ostart;
size_t const nbSeq = seqStorePtr->sequences - seqStorePtr->sequencesStart;
BYTE* seqHead;
BYTE scratchBuffer[1<<MAX(MLFSELog,LLFSELog)];
ZSTD_STATIC_ASSERT(sizeof(zc->entropy->workspace) >= (1<<MAX(MLFSELog,LLFSELog)));
/* Compress literals */
{ const BYTE* const literals = seqStorePtr->litStart;
@ -1058,166 +1196,50 @@ MEM_STATIC size_t ZSTD_compressSequences (ZSTD_CCtx* zc,
/* seqHead : flags for FSE encoding type */
seqHead = op++;
#define MIN_SEQ_FOR_DYNAMIC_FSE 64
#define MAX_SEQ_FOR_STATIC_FSE 1000
/* convert length/distances into codes */
ZSTD_seqToCodes(seqStorePtr);
/* CTable for Literal Lengths */
{ U32 max = MaxLL;
size_t const mostFrequent = FSE_countFast_wksp(count, &max, llCodeTable, nbSeq, zc->entropy->workspace);
if ((mostFrequent == nbSeq) && (nbSeq > 2)) {
*op++ = llCodeTable[0];
FSE_buildCTable_rle(CTable_LitLength, (BYTE)max);
LLtype = set_rle;
zc->entropy->litlength_repeatMode = FSE_repeat_check;
} else if ((zc->entropy->litlength_repeatMode == FSE_repeat_valid) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) {
LLtype = set_repeat;
} else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (LL_defaultNormLog-1)))) {
FSE_buildCTable_wksp(CTable_LitLength, LL_defaultNorm, MaxLL, LL_defaultNormLog, scratchBuffer, sizeof(scratchBuffer));
LLtype = set_basic;
zc->entropy->litlength_repeatMode = FSE_repeat_valid;
} else {
size_t nbSeq_1 = nbSeq;
const U32 tableLog = FSE_optimalTableLog(LLFSELog, nbSeq, max);
if (count[llCodeTable[nbSeq-1]]>1) { count[llCodeTable[nbSeq-1]]--; nbSeq_1--; }
FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max);
{ size_t const NCountSize = FSE_writeNCount(op, oend-op, norm, max, tableLog); /* overflow protected */
if (FSE_isError(NCountSize)) return NCountSize;
op += NCountSize; }
FSE_buildCTable_wksp(CTable_LitLength, norm, max, tableLog, scratchBuffer, sizeof(scratchBuffer));
LLtype = set_compressed;
zc->entropy->litlength_repeatMode = FSE_repeat_check;
LLtype = ZSTD_selectEncodingType(&zc->entropy->litlength_repeatMode, mostFrequent, nbSeq, LL_defaultNormLog);
{ size_t const countSize = ZSTD_buildCTable(op, oend - op, CTable_LitLength, LLFSELog, (symbolEncodingType_e)LLtype,
count, max, llCodeTable, nbSeq, LL_defaultNorm, LL_defaultNormLog, MaxLL,
zc->entropy->workspace, sizeof(zc->entropy->workspace));
if (ZSTD_isError(countSize)) return countSize;
op += countSize;
} }
/* CTable for Offsets */
{ U32 max = MaxOff;
size_t const mostFrequent = FSE_countFast_wksp(count, &max, ofCodeTable, nbSeq, zc->entropy->workspace);
if ((mostFrequent == nbSeq) && (nbSeq > 2)) {
*op++ = ofCodeTable[0];
FSE_buildCTable_rle(CTable_OffsetBits, (BYTE)max);
Offtype = set_rle;
zc->entropy->offcode_repeatMode = FSE_repeat_check;
} else if ((zc->entropy->offcode_repeatMode == FSE_repeat_valid) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) {
Offtype = set_repeat;
} else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (OF_defaultNormLog-1)))) {
FSE_buildCTable_wksp(CTable_OffsetBits, OF_defaultNorm, MaxOff, OF_defaultNormLog, scratchBuffer, sizeof(scratchBuffer));
Offtype = set_basic;
zc->entropy->offcode_repeatMode = FSE_repeat_valid;
} else {
size_t nbSeq_1 = nbSeq;
const U32 tableLog = FSE_optimalTableLog(OffFSELog, nbSeq, max);
if (count[ofCodeTable[nbSeq-1]]>1) { count[ofCodeTable[nbSeq-1]]--; nbSeq_1--; }
FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max);
{ size_t const NCountSize = FSE_writeNCount(op, oend-op, norm, max, tableLog); /* overflow protected */
if (FSE_isError(NCountSize)) return NCountSize;
op += NCountSize; }
FSE_buildCTable_wksp(CTable_OffsetBits, norm, max, tableLog, scratchBuffer, sizeof(scratchBuffer));
Offtype = set_compressed;
zc->entropy->offcode_repeatMode = FSE_repeat_check;
Offtype = ZSTD_selectEncodingType(&zc->entropy->offcode_repeatMode, mostFrequent, nbSeq, OF_defaultNormLog);
{ size_t const countSize = ZSTD_buildCTable(op, oend - op, CTable_OffsetBits, OffFSELog, (symbolEncodingType_e)Offtype,
count, max, ofCodeTable, nbSeq, OF_defaultNorm, OF_defaultNormLog, MaxOff,
zc->entropy->workspace, sizeof(zc->entropy->workspace));
if (ZSTD_isError(countSize)) return countSize;
op += countSize;
} }
/* CTable for MatchLengths */
{ U32 max = MaxML;
size_t const mostFrequent = FSE_countFast_wksp(count, &max, mlCodeTable, nbSeq, zc->entropy->workspace);
if ((mostFrequent == nbSeq) && (nbSeq > 2)) {
*op++ = *mlCodeTable;
FSE_buildCTable_rle(CTable_MatchLength, (BYTE)max);
MLtype = set_rle;
zc->entropy->matchlength_repeatMode = FSE_repeat_check;
} else if ((zc->entropy->matchlength_repeatMode == FSE_repeat_valid) && (nbSeq < MAX_SEQ_FOR_STATIC_FSE)) {
MLtype = set_repeat;
} else if ((nbSeq < MIN_SEQ_FOR_DYNAMIC_FSE) || (mostFrequent < (nbSeq >> (ML_defaultNormLog-1)))) {
FSE_buildCTable_wksp(CTable_MatchLength, ML_defaultNorm, MaxML, ML_defaultNormLog, scratchBuffer, sizeof(scratchBuffer));
MLtype = set_basic;
zc->entropy->matchlength_repeatMode = FSE_repeat_valid;
} else {
size_t nbSeq_1 = nbSeq;
const U32 tableLog = FSE_optimalTableLog(MLFSELog, nbSeq, max);
if (count[mlCodeTable[nbSeq-1]]>1) { count[mlCodeTable[nbSeq-1]]--; nbSeq_1--; }
FSE_normalizeCount(norm, tableLog, count, nbSeq_1, max);
{ size_t const NCountSize = FSE_writeNCount(op, oend-op, norm, max, tableLog); /* overflow protected */
if (FSE_isError(NCountSize)) return NCountSize;
op += NCountSize; }
FSE_buildCTable_wksp(CTable_MatchLength, norm, max, tableLog, scratchBuffer, sizeof(scratchBuffer));
MLtype = set_compressed;
zc->entropy->matchlength_repeatMode = FSE_repeat_check;
MLtype = ZSTD_selectEncodingType(&zc->entropy->matchlength_repeatMode, mostFrequent, nbSeq, ML_defaultNormLog);
{ size_t const countSize = ZSTD_buildCTable(op, oend - op, CTable_MatchLength, MLFSELog, (symbolEncodingType_e)MLtype,
count, max, mlCodeTable, nbSeq, ML_defaultNorm, ML_defaultNormLog, MaxML,
zc->entropy->workspace, sizeof(zc->entropy->workspace));
if (ZSTD_isError(countSize)) return countSize;
op += countSize;
} }
*seqHead = (BYTE)((LLtype<<6) + (Offtype<<4) + (MLtype<<2));
/* Encoding Sequences */
{ BIT_CStream_t blockStream;
FSE_CState_t stateMatchLength;
FSE_CState_t stateOffsetBits;
FSE_CState_t stateLitLength;
{ size_t const streamSize = ZSTD_encodeSequences(op, oend - op,
CTable_MatchLength, mlCodeTable,
CTable_OffsetBits, ofCodeTable,
CTable_LitLength, llCodeTable,
sequences, nbSeq, longOffsets);
if (ZSTD_isError(streamSize)) return streamSize;
op += streamSize;
}
CHECK_E(BIT_initCStream(&blockStream, op, oend-op), dstSize_tooSmall); /* not enough space remaining */
/* first symbols */
FSE_initCState2(&stateMatchLength, CTable_MatchLength, mlCodeTable[nbSeq-1]);
FSE_initCState2(&stateOffsetBits, CTable_OffsetBits, ofCodeTable[nbSeq-1]);
FSE_initCState2(&stateLitLength, CTable_LitLength, llCodeTable[nbSeq-1]);
BIT_addBits(&blockStream, sequences[nbSeq-1].litLength, LL_bits[llCodeTable[nbSeq-1]]);
if (MEM_32bits()) BIT_flushBits(&blockStream);
BIT_addBits(&blockStream, sequences[nbSeq-1].matchLength, ML_bits[mlCodeTable[nbSeq-1]]);
if (MEM_32bits()) BIT_flushBits(&blockStream);
if (longOffsets) {
U32 const ofBits = ofCodeTable[nbSeq-1];
int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN-1);
if (extraBits) {
BIT_addBits(&blockStream, sequences[nbSeq-1].offset, extraBits);
BIT_flushBits(&blockStream);
}
BIT_addBits(&blockStream, sequences[nbSeq-1].offset >> extraBits,
ofBits - extraBits);
} else {
BIT_addBits(&blockStream, sequences[nbSeq-1].offset, ofCodeTable[nbSeq-1]);
}
BIT_flushBits(&blockStream);
{ size_t n;
for (n=nbSeq-2 ; n<nbSeq ; n--) { /* intentional underflow */
BYTE const llCode = llCodeTable[n];
BYTE const ofCode = ofCodeTable[n];
BYTE const mlCode = mlCodeTable[n];
U32 const llBits = LL_bits[llCode];
U32 const ofBits = ofCode; /* 32b*/ /* 64b*/
U32 const mlBits = ML_bits[mlCode];
/* (7)*/ /* (7)*/
FSE_encodeSymbol(&blockStream, &stateOffsetBits, ofCode); /* 15 */ /* 15 */
FSE_encodeSymbol(&blockStream, &stateMatchLength, mlCode); /* 24 */ /* 24 */
if (MEM_32bits()) BIT_flushBits(&blockStream); /* (7)*/
FSE_encodeSymbol(&blockStream, &stateLitLength, llCode); /* 16 */ /* 33 */
if (MEM_32bits() || (ofBits+mlBits+llBits >= 64-7-(LLFSELog+MLFSELog+OffFSELog)))
BIT_flushBits(&blockStream); /* (7)*/
BIT_addBits(&blockStream, sequences[n].litLength, llBits);
if (MEM_32bits() && ((llBits+mlBits)>24)) BIT_flushBits(&blockStream);
BIT_addBits(&blockStream, sequences[n].matchLength, mlBits);
if (MEM_32bits()) BIT_flushBits(&blockStream); /* (7)*/
if (longOffsets) {
int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN-1);
if (extraBits) {
BIT_addBits(&blockStream, sequences[n].offset, extraBits);
BIT_flushBits(&blockStream); /* (7)*/
}
BIT_addBits(&blockStream, sequences[n].offset >> extraBits,
ofBits - extraBits); /* 31 */
} else {
BIT_addBits(&blockStream, sequences[n].offset, ofBits); /* 31 */
}
BIT_flushBits(&blockStream); /* (7)*/
} }
FSE_flushCState(&blockStream, &stateMatchLength);
FSE_flushCState(&blockStream, &stateOffsetBits);
FSE_flushCState(&blockStream, &stateLitLength);
{ size_t const streamSize = BIT_closeCStream(&blockStream);
if (streamSize==0) return ERROR(dstSize_tooSmall); /* not enough space */
op += streamSize;
} }
/* check compressibility */
_check_compressibility: