krak/zstd
1
0
Fork 0
mirror of https://github.com/facebook/zstd.git synced 2025-07-16 20:24:32 +02:00
Code Issues Releases 1 Activity

Merge pull request #838 from stellamplau/ldm-mergeDev

Browse Source 
Add long distance matcher
This commit is contained in:
Yann Collet
2017-09-13 13:24:08 -07:00
committed by GitHub
parent be1f2dac5b 3d8e313f64
commit f1571dad8f
37 changed files with 1433 additions and 136 deletions
Download Patch File Download Diff File Expand all files Collapse all files

177
lib/compress/zstd_compress.c
View File

@ -31,7 +31,7 @@
#include "zstd_double_fast.h"
#include "zstd_lazy.h"
#include "zstd_opt.h"
#include "zstd_ldm.h"
/*-*************************************
@ -65,7 +65,6 @@ struct ZSTD_CDict_s {
ZSTD_CCtx* refContext;
}; /* typedef'd to ZSTD_CDict within "zstd.h" */
ZSTD_CCtx* ZSTD_createCCtx(void)
{
return ZSTD_createCCtx_advanced(ZSTD_defaultCMem);
@ -301,6 +300,24 @@ size_t ZSTD_CCtx_setParameter(ZSTD_CCtx* cctx, ZSTD_cParameter param, unsigned v
DEBUGLOG(5, " setting overlap with nbThreads == %u", cctx->requestedParams.nbThreads);
return ZSTD_CCtxParam_setParameter(&cctx->requestedParams, param, value);
case ZSTD_p_enableLongDistanceMatching:
if (cctx->cdict) return ERROR(stage_wrong);
if (value != 0) {
ZSTD_cLevelToCParams(cctx);
}
return ZSTD_CCtxParam_setParameter(&cctx->requestedParams, param, value);
case ZSTD_p_ldmHashLog:
case ZSTD_p_ldmMinMatch:
if (value == 0) return 0; /* special value : 0 means "don't change anything" */
if (cctx->cdict) return ERROR(stage_wrong);
return ZSTD_CCtxParam_setParameter(&cctx->requestedParams, param, value);
case ZSTD_p_ldmBucketSizeLog:
case ZSTD_p_ldmHashEveryLog:
if (cctx->cdict) return ERROR(stage_wrong);
return ZSTD_CCtxParam_setParameter(&cctx->requestedParams, param, value);
default: return ERROR(parameter_unsupported);
}
}
@ -410,6 +427,39 @@ size_t ZSTD_CCtxParam_setParameter(
return ZSTDMT_CCtxParam_setMTCtxParameter(params, ZSTDMT_p_overlapSectionLog, value);
#endif
case ZSTD_p_enableLongDistanceMatching :
if (value != 0) {
ZSTD_cLevelToCCtxParams(params);
params->cParams.windowLog = ZSTD_LDM_WINDOW_LOG;
}
return ZSTD_ldm_initializeParameters(&params->ldmParams, value);
case ZSTD_p_ldmHashLog :
if (value == 0) return 0;
CLAMPCHECK(value, ZSTD_HASHLOG_MIN, ZSTD_HASHLOG_MAX);
params->ldmParams.hashLog = value;
return 0;
case ZSTD_p_ldmMinMatch :
if (value == 0) return 0;
CLAMPCHECK(value, ZSTD_LDM_MINMATCH_MIN, ZSTD_LDM_MINMATCH_MAX);
params->ldmParams.minMatchLength = value;
return 0;
case ZSTD_p_ldmBucketSizeLog :
if (value > ZSTD_LDM_BUCKETSIZELOG_MAX) {
return ERROR(parameter_outOfBound);
}
params->ldmParams.bucketSizeLog = value;
return 0;
case ZSTD_p_ldmHashEveryLog :
if (value > ZSTD_WINDOWLOG_MAX - ZSTD_HASHLOG_MIN) {
return ERROR(parameter_outOfBound);
}
params->ldmParams.hashEveryLog = value;
return 0;
default: return ERROR(parameter_unsupported);
}
}
@ -445,6 +495,9 @@ size_t ZSTD_CCtx_setParametersUsingCCtxParams(
cctx, ZSTD_p_overlapSizeLog, params->overlapSizeLog) );
}
/* Copy long distance matching parameters */
cctx->requestedParams.ldmParams = params->ldmParams;
/* customMem is used only for create/free params and can be ignored */
return 0;
}
@ -635,7 +688,13 @@ size_t ZSTD_estimateCCtxSize_advanced_usingCCtxParams(const ZSTD_CCtx_params* pa
((MaxML+1) + (MaxLL+1) + (MaxOff+1) + (1<<Litbits))*sizeof(U32)
+ (ZSTD_OPT_NUM+1)*(sizeof(ZSTD_match_t) + sizeof(ZSTD_optimal_t));
size_t const optSpace = ((cParams.strategy == ZSTD_btopt) || (cParams.strategy == ZSTD_btultra)) ? optBudget : 0;
size_t const neededSpace = entropySpace + tableSpace + tokenSpace + optSpace;
size_t const ldmSpace = params->ldmParams.enableLdm ?
ZSTD_ldm_getTableSize(params->ldmParams.hashLog,
params->ldmParams.bucketSizeLog) : 0;
size_t const neededSpace = entropySpace + tableSpace + tokenSpace +
optSpace + ldmSpace;
DEBUGLOG(5, "sizeof(ZSTD_CCtx) : %u", (U32)sizeof(ZSTD_CCtx));
DEBUGLOG(5, "estimate workSpace : %u", (U32)neededSpace);
@ -691,11 +750,25 @@ static U32 ZSTD_equivalentCParams(ZSTD_compressionParameters cParams1,
& ((cParams1.searchLength==3) == (cParams2.searchLength==3)); /* hashlog3 space */
}
/** The parameters are equivalent if ldm is not enabled in both sets or
* all the parameters are equivalent. */
static U32 ZSTD_equivalentLdmParams(ldmParams_t ldmParams1,
ldmParams_t ldmParams2)
{
return (!ldmParams1.enableLdm && !ldmParams2.enableLdm) ||
(ldmParams1.enableLdm == ldmParams2.enableLdm &&
ldmParams1.hashLog == ldmParams2.hashLog &&
ldmParams1.bucketSizeLog == ldmParams2.bucketSizeLog &&
ldmParams1.minMatchLength == ldmParams2.minMatchLength &&
ldmParams1.hashEveryLog == ldmParams2.hashEveryLog);
}
/** Equivalence for resetCCtx purposes */
static U32 ZSTD_equivalentParams(ZSTD_CCtx_params params1,
ZSTD_CCtx_params params2)
{
return ZSTD_equivalentCParams(params1.cParams, params2.cParams);
return ZSTD_equivalentCParams(params1.cParams, params2.cParams) &&
ZSTD_equivalentLdmParams(params1.ldmParams, params2.ldmParams);
}
/*! ZSTD_continueCCtx() :
@ -738,6 +811,8 @@ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc,
if (crp == ZSTDcrp_continue) {
if (ZSTD_equivalentParams(params, zc->appliedParams)) {
DEBUGLOG(5, "ZSTD_equivalentParams()==1");
assert(!(params.ldmParams.enableLdm &&
params.ldmParams.hashEveryLog == ZSTD_LDM_HASHEVERYLOG_NOTSET));
zc->entropy->hufCTable_repeatMode = HUF_repeat_none;
zc->entropy->offcode_repeatMode = FSE_repeat_none;
zc->entropy->matchlength_repeatMode = FSE_repeat_none;
@ -745,6 +820,15 @@ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc,
return ZSTD_continueCCtx(zc, params, pledgedSrcSize);
} }
if (params.ldmParams.enableLdm) {
/* Adjust long distance matching parameters */
ZSTD_ldm_adjustParameters(&params.ldmParams, params.cParams.windowLog);
assert(params.ldmParams.hashLog >= params.ldmParams.bucketSizeLog);
assert(params.ldmParams.hashEveryLog < 32);
zc->ldmState.hashPower =
ZSTD_ldm_getHashPower(params.ldmParams.minMatchLength);
}
{ size_t const blockSize = MIN(ZSTD_BLOCKSIZE_MAX, (size_t)1 << params.cParams.windowLog);
U32 const divider = (params.cParams.searchLength==3) ? 3 : 4;
size_t const maxNbSeq = blockSize / divider;
@ -768,10 +852,13 @@ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc,
|| (params.cParams.strategy == ZSTD_btultra)) ?
optPotentialSpace : 0;
size_t const bufferSpace = buffInSize + buffOutSize;
size_t const neededSpace = entropySpace + optSpace + tableSpace
+ tokenSpace + bufferSpace;
size_t const ldmSpace = params.ldmParams.enableLdm
? ZSTD_ldm_getTableSize(params.ldmParams.hashLog, params.ldmParams.bucketSizeLog)
: 0;
size_t const neededSpace = entropySpace + optSpace + ldmSpace +
tableSpace + tokenSpace + bufferSpace;
if (zc->workSpaceSize < neededSpace) { /* too small : resize /*/
if (zc->workSpaceSize < neededSpace) { /* too small : resize */
DEBUGLOG(5, "Need to update workSpaceSize from %uK to %uK \n",
(unsigned)zc->workSpaceSize>>10,
(unsigned)neededSpace>>10);
@ -836,6 +923,16 @@ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc,
ptr = zc->optState.priceTable + ZSTD_OPT_NUM+1;
}
/* ldm hash table */
/* initialize bucketOffsets table later for pointer alignment */
if (params.ldmParams.enableLdm) {
size_t const ldmHSize = ((size_t)1) << params.ldmParams.hashLog;
memset(ptr, 0, ldmHSize * sizeof(ldmEntry_t));
assert(((size_t)ptr & 3) == 0); /* ensure ptr is properly aligned */
zc->ldmState.hashTable = (ldmEntry_t*)ptr;
ptr = zc->ldmState.hashTable + ldmHSize;
}
/* table Space */
if (crp!=ZSTDcrp_noMemset) memset(ptr, 0, tableSpace); /* reset tables only */
assert(((size_t)ptr & 3) == 0); /* ensure ptr is properly aligned */
@ -853,6 +950,16 @@ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc,
zc->seqStore.litStart = zc->seqStore.ofCode + maxNbSeq;
ptr = zc->seqStore.litStart + blockSize;
/* ldm bucketOffsets table */
if (params.ldmParams.enableLdm) {
size_t const ldmBucketSize =
((size_t)1) << (params.ldmParams.hashLog -
params.ldmParams.bucketSizeLog);
memset(ptr, 0, ldmBucketSize);
zc->ldmState.bucketOffsets = (BYTE*)ptr;
ptr = zc->ldmState.bucketOffsets + ldmBucketSize;
}
/* buffers */
zc->inBuffSize = buffInSize;
zc->inBuff = (char*)ptr;
@ -952,18 +1059,36 @@ static void ZSTD_reduceTable (U32* const table, U32 const size, U32 const reduce
}
}
/*! ZSTD_ldm_reduceTable() :
* reduce table indexes by `reducerValue` */
static void ZSTD_ldm_reduceTable(ldmEntry_t* const table, U32 const size,
U32 const reducerValue)
{
U32 u;
for (u = 0; u < size; u++) {
if (table[u].offset < reducerValue) table[u].offset = 0;
else table[u].offset -= reducerValue;
}
}
/*! ZSTD_reduceIndex() :
* rescale all indexes to avoid future overflow (indexes are U32) */
static void ZSTD_reduceIndex (ZSTD_CCtx* zc, const U32 reducerValue)
{
{ U32 const hSize = 1 << zc->appliedParams.cParams.hashLog;
{ U32 const hSize = (U32)1 << zc->appliedParams.cParams.hashLog;
ZSTD_reduceTable(zc->hashTable, hSize, reducerValue); }
{ U32 const chainSize = (zc->appliedParams.cParams.strategy == ZSTD_fast) ? 0 : (1 << zc->appliedParams.cParams.chainLog);
{ U32 const chainSize = (zc->appliedParams.cParams.strategy == ZSTD_fast) ? 0 : ((U32)1 << zc->appliedParams.cParams.chainLog);
ZSTD_reduceTable(zc->chainTable, chainSize, reducerValue); }
{ U32 const h3Size = (zc->hashLog3) ? 1 << zc->hashLog3 : 0;
{ U32 const h3Size = (zc->hashLog3) ? (U32)1 << zc->hashLog3 : 0;
ZSTD_reduceTable(zc->hashTable3, h3Size, reducerValue); }
{ if (zc->appliedParams.ldmParams.enableLdm) {
U32 const ldmHSize = (U32)1 << zc->appliedParams.ldmParams.hashLog;
ZSTD_ldm_reduceTable(zc->ldmState.hashTable, ldmHSize, reducerValue);
}
}
}
@ -1387,11 +1512,11 @@ MEM_STATIC size_t ZSTD_compressSequences(seqStore_t* seqStorePtr,
return cSize;
}
/* ZSTD_selectBlockCompressor() :
* Not static, but internal use only (used by long distance matcher)
* assumption : strat is a valid strategy */
typedef void (*ZSTD_blockCompressor) (ZSTD_CCtx* ctx, const void* src, size_t srcSize);
static ZSTD_blockCompressor ZSTD_selectBlockCompressor(ZSTD_strategy strat, int extDict)
typedef size_t (*ZSTD_blockCompressor) (ZSTD_CCtx* ctx, const void* src, size_t srcSize);
ZSTD_blockCompressor ZSTD_selectBlockCompressor(ZSTD_strategy strat, int extDict)
{
static const ZSTD_blockCompressor blockCompressor[2][(unsigned)ZSTD_btultra+1] = {
{ ZSTD_compressBlock_fast /* default for 0 */,
@ -1410,18 +1535,37 @@ static ZSTD_blockCompressor ZSTD_selectBlockCompressor(ZSTD_strategy strat, int
return blockCompressor[extDict!=0][(U32)strat];
}
static void ZSTD_storeLastLiterals(seqStore_t* seqStorePtr,
const BYTE* anchor, size_t lastLLSize)
{
memcpy(seqStorePtr->lit, anchor, lastLLSize);
seqStorePtr->lit += lastLLSize;
}
static size_t ZSTD_compressBlock_internal(ZSTD_CCtx* zc, void* dst, size_t dstCapacity, const void* src, size_t srcSize)
{
ZSTD_blockCompressor const blockCompressor = ZSTD_selectBlockCompressor(zc->appliedParams.cParams.strategy, zc->lowLimit < zc->dictLimit);
const BYTE* const base = zc->base;
const BYTE* const istart = (const BYTE*)src;
const U32 current = (U32)(istart-base);
size_t lastLLSize;
const BYTE* anchor;
U32 const extDict = zc->lowLimit < zc->dictLimit;
const ZSTD_blockCompressor blockCompressor =
zc->appliedParams.ldmParams.enableLdm
? (extDict ? ZSTD_compressBlock_ldm_extDict : ZSTD_compressBlock_ldm)
: ZSTD_selectBlockCompressor(zc->appliedParams.cParams.strategy, extDict);
if (srcSize < MIN_CBLOCK_SIZE+ZSTD_blockHeaderSize+1) return 0; /* don't even attempt compression below a certain srcSize */
ZSTD_resetSeqStore(&(zc->seqStore));
if (current > zc->nextToUpdate + 384)
zc->nextToUpdate = current - MIN(192, (U32)(current - zc->nextToUpdate - 384)); /* limited update after finding a very long match */
blockCompressor(zc, src, srcSize);
lastLLSize = blockCompressor(zc, src, srcSize);
/* Last literals */
anchor = (const BYTE*)src + srcSize - lastLLSize;
ZSTD_storeLastLiterals(&zc->seqStore, anchor, lastLLSize);
return ZSTD_compressSequences(&zc->seqStore, zc->entropy, &zc->appliedParams.cParams, dst, dstCapacity, srcSize);
}
@ -1645,7 +1789,6 @@ static size_t ZSTD_loadDictionaryContent(ZSTD_CCtx* zc, const void* src, size_t
case ZSTD_fast:
ZSTD_fillHashTable (zc, iend, zc->appliedParams.cParams.searchLength);
break;
case ZSTD_dfast:
ZSTD_fillDoubleHashTable (zc, iend, zc->appliedParams.cParams.searchLength);
break;
@ -2578,7 +2721,6 @@ size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
cctx->mtctx = ZSTDMT_createCCtx_advanced(params.nbThreads, cctx->customMem);
if (cctx->mtctx == NULL) return ERROR(memory_allocation);
}
DEBUGLOG(4, "call ZSTDMT_initCStream_internal as nbThreads=%u", params.nbThreads);
CHECK_F( ZSTDMT_initCStream_internal(
cctx->mtctx,
@ -2607,7 +2749,6 @@ size_t ZSTD_compress_generic (ZSTD_CCtx* cctx,
return flushMin;
}
#endif
CHECK_F( ZSTD_compressStream_generic(cctx, output, input, endOp) );
DEBUGLOG(5, "completed ZSTD_compress_generic");
return cctx->outBuffContentSize - cctx->outBuffFlushedSize; /* remaining to flush */