Truncate Chain at Last Possible Attempt

Make the chain table denser?
This commit is contained in:
W. Felix Handte 2020-09-03 13:58:11 -04:00
parent 20a020edbc
commit f42c5bddd9

View File

@ -487,7 +487,9 @@ void ZSTD_dedicatedDictSearch_lazy_loadDictionary(ZSTD_matchState_t* ms, const B
U32 const chainMask = chainSize - 1;
U32 idx = ms->nextToUpdate;
U32 const minChain = chainSize < target ? target - chainSize : idx;
U32 bucketSize = 1 << ZSTD_LAZY_DDSS_BUCKET_LOG;
U32 const bucketSize = 1 << ZSTD_LAZY_DDSS_BUCKET_LOG;
U32 const nbAttempts = (1 << ms->cParams.searchLog) - bucketSize + 1;
U32 const chainLimit = nbAttempts > 255 ? 255 : nbAttempts;
U32* const chains = (U32*)malloc(chainSize * sizeof(U32));
assert(chains != NULL);
assert(idx != 0);
@ -517,7 +519,7 @@ void ZSTD_dedicatedDictSearch_lazy_loadDictionary(ZSTD_matchState_t* ms, const B
while (i) {
chainTable[chainPos++] = i;
count++;
if (i < minChain || count >= 255) {
if (i < minChain || count >= chainLimit) {
break;
}
i = chains[i & chainMask];