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Add new sequence compress api params to cctx

dev
senhuang42 2020-11-11 16:28:17 -05:00
parent 48405b4633
commit 46824cb018
3 changed files with 121 additions and 193 deletions
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296
lib/compress/zstd_compress.c
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@ -1718,6 +1718,9 @@ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc,
zc->ldmState.loadedDictEnd = 0;
}
zc->blockDelimiters = ZSTD_sf_noBlockDelimiters;
zc->calculateRepcodes = ZSTD_sf_calculateRepcodes;
/* Due to alignment, when reusing a workspace, we can actually consume
* up to 3 extra bytes for alignment. See the comments in zstd_cwksp.h
*/
@ -2533,7 +2536,7 @@ static void ZSTD_copyBlockSequences(ZSTD_CCtx* zc)
outSeqs[i].offset = rawOffset;
/* seqStoreSeqs[i].offset == offCode+1, and ZSTD_updateRep() expects offCode
so we provide seqStoreSeqs[i].offset - 1 */
updatedRepcodes = ZSTD_updateRep(rep,
updatedRepcodes = ZSTD_updateRep(updatedRepcodes.rep,
seqStoreSeqs[i].offset - 1,
seqStoreSeqs[i].litLength == 0);
literalsRead += outSeqs[i].litLength;
@ -4472,205 +4475,125 @@ size_t ZSTD_compress2(ZSTD_CCtx* cctx,
}
typedef struct {
U32 startIdx; /* Index in array of ZSTD_Sequence where range begins */
U32 startPosInSequence; /* Position within sequence at index 'startIdx' where range begins */
U32 endIdx; /* Index in array of ZSTD_Sequence where range ends */
U32 endPosInSequence; /* Position within sequence at index 'endIdx' where range ends */
} ZSTD_sequenceRange;
U32 idx; /* Index in array of ZSTD_Sequence*/
U32 posInSequence; /* Position within sequence at idx */
} ZSTD_sequencePosition;
/* Attempts to move the sequenceRange forward by blockSize bytes.
*
* If the ending position of the sequenceRange is within a match, it may be split. If
* we cannot split a match (due to creating a match too small), we slightly adjust
* the ending position, which will move sequenceRange forward by
* more or less bytes than blockSize.
*
* Returns the number of additional bytes consumed, after blockSize. Can be negative.
*/
static int ZSTD_updateSequenceRange(ZSTD_sequenceRange* sequenceRange, size_t blockSize,
const ZSTD_Sequence* const inSeqs, size_t inSeqsSize,
ZSTD_sequenceFormat_e format) {
U32 idx = sequenceRange->endIdx;
U32 endPosInSequence = sequenceRange->endPosInSequence + blockSize;
int bytesAdjustment = 0;
DEBUGLOG(4, "ZSTD_updateSequenceRange: %zu bytes, startidx %u startpos: %u endidx: %u endpos: %u", blockSize,
sequenceRange->startIdx, sequenceRange->startPosInSequence, sequenceRange->endIdx, sequenceRange->endPosInSequence);
DEBUGLOG(5, "endPosInSequence begin val: %u", endPosInSequence);
static size_t ZSTD_copySequencesToSeqStore(seqStore_t* seqStore, ZSTD_sequencePosition* seqPos,
const ZSTD_Sequence* const inSeqs, size_t inSeqsSize,
const void* src, size_t blockSize, ZSTD_CCtx* cctx) {
size_t idx = seqPos->idx;
size_t startPosInSequence = seqPos->posInSequence;
size_t endPosInSequence = seqPos->posInSequence + blockSize;
BYTE const* ip = (BYTE const*)(src);
const BYTE* const iend = ip + blockSize;
U32 windowSize = 1 << cctx->appliedParams.cParams.windowLog;
repcodes_t updatedRepcodes;
U32 bytesAdjustment = 0;
U32 bytesread = 0;
DEBUGLOG(3, "ZSTD_copySequencesToSeqStore: idx: %zu PIS: %u blockSize: %zu windowSize: %u", idx, startPosInSequence, blockSize, windowSize);
DEBUGLOG(3, "start seq: idx: %u (of: %u ml: %u ll: %u)", idx, inSeqs[idx].offset, inSeqs[idx].matchLength, inSeqs[idx].litLength);
ZSTD_memcpy(updatedRepcodes.rep, cctx->blockState.prevCBlock->rep, sizeof(repcodes_t));
while (endPosInSequence && idx < inSeqsSize) {
ZSTD_Sequence currSeq = inSeqs[idx];
U32 litLength = currSeq.litLength;
U32 matchLength = currSeq.matchLength;
U32 rawOffset = currSeq.offset;
U32 offCode = rawOffset + ZSTD_REP_MOVE;
U32 repCode = cctx->calculateRepcodes ? 0 : currSeq.rep;
/* Modify the sequence depending on where endPosInSequence lies */
if (endPosInSequence >= currSeq.litLength + currSeq.matchLength) {
if (startPosInSequence >= litLength) {
/* Start pos is within the match */
startPosInSequence -= litLength;
litLength = 0;
matchLength -= startPosInSequence;
} else {
litLength -= startPosInSequence;
}
/* Move to the next sequence */
endPosInSequence -= currSeq.litLength + currSeq.matchLength;
startPosInSequence = 0;
idx++;
} else {
break;
}
}
if (idx == inSeqsSize) {
endPosInSequence = 0;
}
if (format == ZSTD_sf_noBlockDelimiters) {
assert(endPosInSequence <= inSeqs[idx].litLength + inSeqs[idx].matchLength);
if (idx != inSeqsSize && endPosInSequence > inSeqs[idx].litLength) {
DEBUGLOG(5, "Endpos is in the match");
if (inSeqs[idx].matchLength >= blockSize) {
/* Only split the match if it's too large */
U32 firstHalfMatchLength = endPosInSequence - inSeqs[idx].litLength;
U32 secondHalfMatchLength = inSeqs[idx].matchLength - firstHalfMatchLength;
assert(firstHalfMatchLength >= MINMATCH || secondHalfMatchLength >= MINMATCH);
if (firstHalfMatchLength < MINMATCH && firstHalfMatchLength != 0) {
/* Move the endPos forward so that it creates match of at least MINMATCH length */
endPosInSequence = MINMATCH + inSeqs[idx].litLength;
bytesAdjustment = MINMATCH - firstHalfMatchLength;
} else if (secondHalfMatchLength < MINMATCH && secondHalfMatchLength != 0) {
/* Move the endPos backward so that it creates match of at least MINMATCH length */
endPosInSequence -= MINMATCH - secondHalfMatchLength;
bytesAdjustment = secondHalfMatchLength - MINMATCH;
/* This is the final sequence we're adding from inSeqs, and endPosInSequence
does not reach the end of the match. So, we have to split something */
DEBUGLOG(3, "Require a split: diff: %u, idx: %u PIS: %u", currSeq.litLength + currSeq.matchLength - endPosInSequence, idx, endPosInSequence);
DEBUGLOG(3, "(of: %u ml: %u ll: %u)", rawOffset, matchLength, litLength);
if (endPosInSequence > litLength) {
DEBUGLOG(2, "hard case");
/* This sequence ends inside the match, may need to split match */
U32 firstHalfMatchLength = endPosInSequence - litLength;
if (matchLength > blockSize && firstHalfMatchLength >= MINMATCH) {
U32 secondHalfMatchLength = matchLength - firstHalfMatchLength;
if (secondHalfMatchLength < MINMATCH) {
/* Move the endPosInSequence backward so that it creates match of MINMATCH length */
endPosInSequence -= MINMATCH - secondHalfMatchLength;
bytesAdjustment = MINMATCH - secondHalfMatchLength;
firstHalfMatchLength -= bytesAdjustment;
}
matchLength = firstHalfMatchLength;
} else {
/* Move the position in sequence backwards so that we don't split match, and store
the last literals */
DEBUGLOG(2, "MOVING SEQ BACKWARDS");
bytesAdjustment = endPosInSequence - litLength;
endPosInSequence = litLength;
break;
}
} else {
/* If we can, prefer to simply move endPos to the end of the literals, so they can
* be stored as last literals.
*/
bytesAdjustment = (int)inSeqs[idx].litLength - (int)endPosInSequence;
endPosInSequence = inSeqs[idx].litLength;
/* This sequence ends inside the literals, store the last literals */
litLength = startPosInSequence >= litLength ? 0 : endPosInSequence - startPosInSequence;
break;
}
}
}
sequenceRange->startIdx = sequenceRange->endIdx;
sequenceRange->startPosInSequence = sequenceRange->endPosInSequence;
sequenceRange->endIdx = idx;
sequenceRange->endPosInSequence = endPosInSequence;
if (idx < inSeqsSize) {
assert(sequenceRange->startPosInSequence <= inSeqs[sequenceRange->startIdx].litLength + inSeqs[sequenceRange->startIdx].matchLength);
assert(sequenceRange->endPosInSequence <= inSeqs[sequenceRange->endIdx].litLength + inSeqs[sequenceRange->endIdx].matchLength);
DEBUGLOG(5, "endidx: (of: %u ml: %u ll: %u)", inSeqs[sequenceRange->endIdx].offset, inSeqs[sequenceRange->endIdx].matchLength, inSeqs[sequenceRange->endIdx].litLength);
}
DEBUGLOG(4, "finished update: startidx %u startpos: %u endidx: %u endpos: %u",
sequenceRange->startIdx, sequenceRange->startPosInSequence, sequenceRange->endIdx, sequenceRange->endPosInSequence);
DEBUGLOG(5, "final PIS was additionally adjusted by: %d bytes", bytesAdjustment);
return bytesAdjustment;
}
/* Given a seqStore and a seqRange, we copy all sequences within the seqRange into the seqStore.
* The sequences at seqRange->startIdx and seqRange->endIdx may not necessarily be inserted in their
* entirety, if seqRange->startPosInSequence or seqRange->endPosInSequence != 0.
*
* Returns size of sequences range copied, otherwise ZSTD error code
*/
static size_t ZSTD_copySequencesToSeqStore(seqStore_t* seqStore, const ZSTD_sequenceRange* seqRange,
const ZSTD_Sequence* const inSeqs, size_t inSeqsSize,
const void* src, size_t srcSize, ZSTD_sequenceFormat_e format,
size_t windowSize) {
size_t idx = seqRange->startIdx;
BYTE const* ip = (BYTE const*)src;
const BYTE* const iend = ip + srcSize;
DEBUGLOG(4, "ZSTD_copySequencesToSeqStore: numSeqs: %zu srcSize: %zu", inSeqsSize, srcSize);
for (; idx < inSeqsSize && idx <= seqRange->endIdx; ++idx) {
U32 litLength = inSeqs[idx].litLength;
U32 matchLength = inSeqs[idx].matchLength;
U32 offCode = inSeqs[idx].offset + ZSTD_REP_MOVE;
RETURN_ERROR_IF(inSeqs[idx].offset > windowSize, corruption_detected, "Offset too large!");
/* Adjust litLength and matchLength if we're at either the start or end index of the range */
if (seqRange->startIdx == seqRange->endIdx) {
/* The sequence spans the entire block */
U32 seqLength = seqRange->endPosInSequence - seqRange->startPosInSequence;
DEBUGLOG(5, "Range within single sequence: idx: %zu (of: %u ml: %u ll: %u) rep: %u",
idx, offCode, matchLength, litLength, inSeqs[idx].rep);
RETURN_ERROR_IF(seqLength > litLength + matchLength, corruption_detected,
"range length cannot be bigger than sequence length!");
if (seqLength <= litLength) {
/* Spanned range is entirely literals, store as last literals */
break;
} else {
/* Spanned range ends in the match section */
litLength = seqRange->startPosInSequence > litLength ? 0 : litLength - seqRange->startPosInSequence;
matchLength = seqLength - litLength;
}
/* ZSTD_updateSequenceRange should never give us a position such that we generate a match too small */
RETURN_ERROR_IF(matchLength < MINMATCH && offCode != ZSTD_REP_MOVE, corruption_detected,
"Matchlength too small for sequence spanning a whole block!");
DEBUGLOG(5, "seq finalized: (of: %u ml: %u ll: %u) rep: %u", offCode, matchLength, litLength, inSeqs[idx].rep);
} else if (idx == seqRange->startIdx) {
/* Modify the sequence at the start of the range as necessary */
U32 posInSequence = seqRange->startPosInSequence;
DEBUGLOG(5, "startIdx: %zu PIS: %u", idx, posInSequence);
DEBUGLOG(5, "startIdx seq initial: (of: %u ml: %u ll: %u) rep: %u", offCode, matchLength, litLength, inSeqs[idx].rep);
assert(posInSequence <= litLength + matchLength);
RETURN_ERROR_IF(format == ZSTD_sf_explicitBlockDelimiters && posInSequence != 0,
corruption_detected, "pos in sequence must == 0 when using block delimiters!");
if (posInSequence >= litLength) {
/* posInSequence is within the match:
* final matchLength = length from posInSequence to the end of the match */
posInSequence -= litLength;
litLength = 0;
matchLength -= posInSequence;
} else {
/* posInSequence is within the literals */
litLength -= posInSequence;
}
/* ZSTD_updateSequenceRange should never give us a position such that we generate a match too small */
RETURN_ERROR_IF(matchLength < MINMATCH && offCode != ZSTD_REP_MOVE, corruption_detected,
"Matchlength too small at start of range!");
DEBUGLOG(5, "startIdx seq finalized: (of: %u ml: %u ll: %u) rep: %u", offCode, matchLength, litLength, inSeqs[idx].rep);
} else if (idx == seqRange->endIdx) {
U32 posInSequence = seqRange->endPosInSequence;
DEBUGLOG(5, "endIdx: %zu PIS: %u", idx, posInSequence);
DEBUGLOG(5, "endIdx seq initial: (of: %u ml: %u ll: %u) rep: %u", offCode, matchLength, litLength, inSeqs[idx].rep);
assert(posInSequence <= litLength + matchLength);
RETURN_ERROR_IF(format == ZSTD_sf_explicitBlockDelimiters && posInSequence != 0,
corruption_detected, "pos in sequence must == 0 when using block delimiters!");
if (posInSequence <= litLength) {
/* posInSequence is within the literals, break and store as last literals if any */
break;
} else {
/* posInSequence is within the match, reduce matchLength if necessary, maintain litLength */
matchLength = posInSequence - litLength;
}
/* ZSTD_updateSequenceRange should never give us a position such that we generate a match too small */
RETURN_ERROR_IF(matchLength < MINMATCH && offCode != ZSTD_REP_MOVE, corruption_detected,
"Matchlength too small at end of range!");
DEBUGLOG(5, "endIdx seq finalized: (of: %u ml: %u ll: %u) rep: %u", offCode, matchLength, litLength, inSeqs[idx].rep);
if (matchLength < MINMATCH) {
DEBUGLOG(2, "match too small");
DEBUGLOG(2, "%u (of: %u ml: %u ll: %u)", idx, rawOffset, matchLength, litLength);
RETURN_ERROR_IF(1, corruption_detected, "match");
}
/* ML == 0 and Offset == 0 (or offCode == ZSTD_REP_MOVE) signals block delimiters */
if (matchLength == 0 && offCode == ZSTD_REP_MOVE) {
RETURN_ERROR_IF(format == ZSTD_sf_noBlockDelimiters, corruption_detected, "No block delimiters allowed!");
if (litLength > 0) {
const BYTE* const lastLiterals = (const BYTE*)src + srcSize - litLength;
ZSTD_storeLastLiterals(seqStore, lastLiterals, litLength);
DEBUGLOG(5, "Storing block delim last literals: %u bytes, idx: %zu", litLength, idx);
if (cctx->calculateRepcodes == ZSTD_sf_calculateRepcodes) {
U32 ll0 = (litLength == 0);
/* Check if current offset matches anything in the repcode table */
if (!ll0 && rawOffset == updatedRepcodes.rep[0]) {
repCode = 1;
} else if (rawOffset == updatedRepcodes.rep[1]) {
repCode = 2 - ll0;
} else if (rawOffset == updatedRepcodes.rep[2]) {
repCode = 3 - ll0;
} else if (ll0 && rawOffset == updatedRepcodes.rep[0] - 1) {
repCode = 3;
}
if (repCode) {
offCode = repCode - 1;
}
updatedRepcodes = ZSTD_updateRep(updatedRepcodes.rep, offCode, ll0);
} else {
DEBUGLOG(6, "Storing: idx: %zu (ll: %u, ml: %u, of: %u) rep: %u", idx, litLength, matchLength - MINMATCH, offCode, inSeqs[idx].rep);
RETURN_ERROR_IF(matchLength < MINMATCH, corruption_detected, "Matchlength too small! of: %u ml: %u ll: %u", offCode, matchLength, litLength);
if (inSeqs[idx].rep) {
ZSTD_storeSeq(seqStore, litLength, ip, iend, inSeqs[idx].rep - 1, matchLength - MINMATCH);
} else {
ZSTD_storeSeq(seqStore, litLength, ip, iend, offCode, matchLength - MINMATCH);
}
offCode = repCode ? repCode-1 : offCode;
}
DEBUGLOG(6, "Storing: idx: %zu (of: %u, ml: %u, ll: %u)", idx, offCode, matchLength, litLength);
/* Validate the offCode */
ZSTD_storeSeq(seqStore, litLength, ip, iend, offCode, matchLength - MINMATCH);
ip += matchLength + litLength;
bytesread += matchLength + litLength;
}
assert(endPosInSequence <= inSeqs[idx].litLength + inSeqs[idx].matchLength);
seqPos->idx = idx;
seqPos->posInSequence = endPosInSequence;
/* Update repcodes */
ZSTD_memcpy(cctx->blockState.nextCBlock->rep, updatedRepcodes.rep, sizeof(repcodes_t));
/* Store any last literals for ZSTD_sf_noBlockDelimiters mode */
if (format == ZSTD_sf_noBlockDelimiters && ip != iend) {
if (cctx->blockDelimiters == ZSTD_sf_noBlockDelimiters && ip != iend) {
U32 lastLLSize = (U32)(iend - ip);
assert(ip <= iend);
DEBUGLOG(5, "Storing last literals of size: %u", lastLLSize);
DEBUGLOG(2, "Storing last literals of size: %u", lastLLSize);
ZSTD_storeLastLiterals(seqStore, ip, lastLLSize);
}
DEBUGLOG(5, "ZSTD_copySequencesToSeqStore: done");
return 0;
return bytesAdjustment;
}
/* Compress, block-by-block, all of the sequences given.
@ -4680,14 +4603,13 @@ static size_t ZSTD_copySequencesToSeqStore(seqStore_t* seqStore, const ZSTD_sequ
static size_t ZSTD_compressSequences_internal(void* dst, size_t dstCapacity,
ZSTD_CCtx* cctx,
const ZSTD_Sequence* inSeqs, size_t inSeqsSize,
const void* src, size_t srcSize,
ZSTD_sequenceFormat_e format) {
const void* src, size_t srcSize) {
U32 cSize = 0;
U32 lastBlock;
U32 blockSize;
U32 compressedSeqsSize;
size_t remaining = srcSize;
ZSTD_sequenceRange seqRange = {0, 0, 0, 0};
ZSTD_sequencePosition seqPos = {0, 0};
seqStore_t blockSeqStore;
BYTE const* ip = (BYTE const*)src;
@ -4711,10 +4633,11 @@ static size_t ZSTD_compressSequences_internal(void* dst, size_t dstCapacity,
blockSize = lastBlock ? (U32)remaining : (U32)cctx->blockSize;
blockSeqStore = cctx->seqStore;
ZSTD_resetSeqStore(&blockSeqStore);
additionalByteAdjustment = ZSTD_updateSequenceRange(&seqRange, blockSize, inSeqs, inSeqsSize, format);
blockSize += additionalByteAdjustment;
DEBUGLOG(4, "Working on new block. Blocksize: %u", blockSize);
additionalByteAdjustment = ZSTD_copySequencesToSeqStore(&blockSeqStore, &seqPos, inSeqs, inSeqsSize, ip, blockSize, cctx);
FORWARD_IF_ERROR(additionalByteAdjustment, "Bad sequence copy");
blockSize -= additionalByteAdjustment;
/* If blocks are too small, emit as a nocompress block */
if (blockSize < MIN_CBLOCK_SIZE+ZSTD_blockHeaderSize+1) {
cBlockSize = ZSTD_noCompressBlock(op, dstCapacity, ip, blockSize, lastBlock);
@ -4728,8 +4651,6 @@ static size_t ZSTD_compressSequences_internal(void* dst, size_t dstCapacity,
continue;
}
FORWARD_IF_ERROR(ZSTD_copySequencesToSeqStore(&blockSeqStore, &seqRange, inSeqs, inSeqsSize, ip, blockSize, format, 1 << cctx->appliedParams.cParams.windowLog),
"Sequence copying failed");
compressedSeqsSize = ZSTD_entropyCompressSequences(&blockSeqStore,
&cctx->blockState.prevCBlock->entropy, &cctx->blockState.nextCBlock->entropy,
&cctx->appliedParams,
@ -4791,9 +4712,8 @@ static size_t ZSTD_compressSequences_internal(void* dst, size_t dstCapacity,
}
size_t ZSTD_compressSequences(ZSTD_CCtx* const cctx, void* dst, size_t dstCapacity,
const ZSTD_Sequence* inSeqs, size_t inSeqsSize,
const void* src, size_t srcSize,
ZSTD_sequenceFormat_e format) {
const ZSTD_Sequence* inSeqs, size_t inSeqsSize,
const void* src, size_t srcSize) {
BYTE* op = (BYTE*)dst;
size_t cSize = 0;
size_t compressedBlocksSize = 0;
@ -4818,7 +4738,7 @@ size_t ZSTD_compressSequences(ZSTD_CCtx* const cctx, void* dst, size_t dstCapaci
/* cSize includes block header size and compressed sequences size */
compressedBlocksSize = ZSTD_compressSequences_internal(op, dstCapacity,
cctx, inSeqs, inSeqsSize,
src, srcSize, format);
src, srcSize);
FORWARD_IF_ERROR(compressedBlocksSize, "Compressing blocks failed!");
cSize += compressedBlocksSize;
dstCapacity -= compressedBlocksSize;

4
lib/compress/zstd_compress_internal.h
View File

@ -313,6 +313,10 @@ struct ZSTD_CCtx_s {
const ZSTD_CDict* cdict;
ZSTD_prefixDict prefixDict; /* single-usage dictionary */
/* Sequence compression API */
ZSTD_sequenceFormat_blockBoundaries_e blockDelimiters;
ZSTD_sequenceFormat_repcodes_e calculateRepcodes;
/* Multi-threading */
#ifdef ZSTD_MULTITHREAD
ZSTDMT_CCtx* mtctx;

14
lib/zstd.h
View File

@ -1298,9 +1298,14 @@ ZSTDLIB_API unsigned long long ZSTD_decompressBound(const void* src, size_t srcS
ZSTDLIB_API size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize);
typedef enum {
ZSTD_sf_explicitBlockDelimiters, /* Representation of ZSTD_Sequence contains explicit block delimiters */
ZSTD_sf_noBlockDelimiters /* Representation of ZSTD_Sequence has no block delimiters, sequences only */
} ZSTD_sequenceFormat_e;
ZSTD_sf_noBlockDelimiters, /* Representation of ZSTD_Sequence has no block delimiters, sequences only */
ZSTD_sf_explicitBlockDelimiters /* Representation of ZSTD_Sequence contains explicit block delimiters */
} ZSTD_sequenceFormat_blockBoundaries_e;
typedef enum {
ZSTD_sf_calculateRepcodes,
ZSTD_sf_noCalculateRepcodes
} ZSTD_sequenceFormat_repcodes_e;
/*! ZSTD_generateSequences() :
* Generate sequences using ZSTD_compress2, given a source buffer.
@ -1343,8 +1348,7 @@ ZSTDLIB_API size_t ZSTD_mergeBlockDelimiters(ZSTD_Sequence* sequences, size_t se
*/
ZSTDLIB_API size_t ZSTD_compressSequences(ZSTD_CCtx* const cctx, void* dst, size_t dstSize,
const ZSTD_Sequence* inSeqs, size_t inSeqsSize,
const void* src, size_t srcSize,
ZSTD_sequenceFormat_e format);
const void* src, size_t srcSize);
/***************************************