[libzstd] Refactor ZSTD_compressSequences()
diff --git a/lib/compress/zstd_compress.c b/lib/compress/zstd_compress.c
index dfcb026..3c792a8 100644
--- a/lib/compress/zstd_compress.c
+++ b/lib/compress/zstd_compress.c
@@ -1017,6 +1017,144 @@
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 @@
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 @@
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 @@
/* 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:
