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derive hashratelog from hashlog when only hashlog is set

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This commit is contained in:
Yann Collet 2025-02-09 11:11:49 -08:00
parent 339bca6606
commit 67fad95f79
1 changed files with 15 additions and 10 deletions
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25
lib/compress/zstd_ldm.c
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@ -133,18 +133,26 @@ done:
}
void ZSTD_ldm_adjustParameters(ldmParams_t* params,
ZSTD_compressionParameters const* cParams)
const ZSTD_compressionParameters* cParams)
{
params->windowLog = cParams->windowLog;
ZSTD_STATIC_ASSERT(LDM_BUCKET_SIZE_LOG <= ZSTD_LDM_BUCKETSIZELOG_MAX);
DEBUGLOG(4, "ZSTD_ldm_adjustParameters");
if (params->hashRateLog == 0) {
assert(1 <= (int)cParams->strategy && (int)cParams->strategy <= 9);
/* mapping: strat1 -> rate8 ... strat9 -> rate4*/
params->hashRateLog = 7 - (cParams->strategy/3);
if (params->hashLog > 0) {
/* if params->hashLog is set, derive hashRateLog from it */
assert(params->hashLog <= ZSTD_HASHLOG_MAX);
if (params->windowLog > params->hashLog) {
params->hashRateLog = params->windowLog - params->hashLog;
}
} else {
assert(1 <= (int)cParams->strategy && (int)cParams->strategy <= 9);
/* mapping: strat1 -> rate8 ... strat9 -> rate4*/
params->hashRateLog = 7 - (cParams->strategy/3);
}
}
if (params->hashLog == 0) {
params->hashLog = MIN(MAX(ZSTD_HASHLOG_MIN, params->windowLog - params->hashRateLog), ZSTD_HASHLOG_MAX);
params->hashLog = BOUNDED(ZSTD_HASHLOG_MIN, params->windowLog - params->hashRateLog, ZSTD_HASHLOG_MAX);
}
if (params->minMatchLength == 0) {
params->minMatchLength = LDM_MIN_MATCH_LENGTH;
@ -152,11 +160,8 @@ void ZSTD_ldm_adjustParameters(ldmParams_t* params,
params->minMatchLength /= 2;
}
if (params->bucketSizeLog==0) {
params->bucketSizeLog = LDM_BUCKET_SIZE_LOG;
if (cParams->strategy > ZSTD_lazy) {
params->bucketSizeLog += (U32)cParams->strategy - (U32)ZSTD_lazy;
}
params->bucketSizeLog = MIN(params->bucketSizeLog, ZSTD_LDM_BUCKETSIZELOG_MAX);
assert(1 <= (int)cParams->strategy && (int)cParams->strategy <= 9);
params->bucketSizeLog = BOUNDED(LDM_BUCKET_SIZE_LOG, (U32)cParams->strategy, ZSTD_LDM_BUCKETSIZELOG_MAX);
}
params->bucketSizeLog = MIN(params->bucketSizeLog, params->hashLog);
}