protected override HasherSearchResult.BackReferenceBuilder FindLongestBackReference(int ip, int maxLength, int maxDistance, int lastDistance, int bestLenIn)
{
byte compareChar = input[ip + bestLenIn];
uint key = HashBytes(input, ip);
var result = new HasherSearchResult.BackReferenceBuilder {
Len = bestLenIn
};
int bestScore = result.Score;
int bestLen = result.Len;
int cachedBackward = lastDistance;
int prevIp = ip - cachedBackward;
if (prevIp < ip && prevIp >= 0 && compareChar == input[prevIp + bestLen])
{
int len = Match.DetermineLength(input, prevIp, ip, maxLength);
if (len >= 4)
{
int score = HasherSearchResult.BackwardReferenceScoreUsingLastDistance(len);
if (bestScore < score)
{
result.Len = len;
result.Distance = cachedBackward;
result.Score = score;
bestLen = len;
bestScore = score;
compareChar = input[ip + len];
}
}
}
var keys = new uint[sweep];
for (int i = 0; i < sweep; i++)
{
keys[i] = (uint)((key + (i << 3)) & bucketMask);
}
uint keyOut = keys[(ip & sweepMask) >> 3];
for (int i = 0; i < sweep; i++)
{
prevIp = table[keys[i]];
int backward = ip - prevIp;
if (compareChar != input[prevIp + bestLen])
{
continue;
}
if (backward == 0 || backward > maxDistance)
{
continue;
}
int len = Match.DetermineLength(input, prevIp, ip, maxLength);
if (len >= 4)
{
int score = HasherSearchResult.BackwardReferenceScore(len, backward);
if (bestScore < score)
{
result.Len = bestLen = len;
result.Score = bestScore = score;
result.Distance = backward;
compareChar = input[ip + len];
}
}
}
table[keyOut] = ip;
return(result);
}
protected override HasherSearchResult.BackReferenceBuilder FindLongestBackReference(int ip, int maxLength, int maxDistance, int lastDistance, int bestLenIn)
{
byte compareChar = input[ip + bestLenIn];
uint key = HashBytes(input, ip);
var result = new HasherSearchResult.BackReferenceBuilder {
Len = bestLenIn
};
int bestScore = result.Score;
int bestLen = result.Len;
int cachedBackward = lastDistance;
int prevIp = ip - cachedBackward;
int len;
if (prevIp < ip && prevIp >= 0 && compareChar == input[prevIp + bestLen])
{
len = Match.DetermineLength(input, prevIp, ip, maxLength);
if (len >= 4)
{
int score = HasherSearchResult.BackwardReferenceScoreUsingLastDistance(len);
if (bestScore < score)
{
result.Len = len;
result.Distance = cachedBackward;
result.Score = score;
table[key] = ip;
return(result);
}
}
}
prevIp = table[key];
table[key] = ip;
int backward = ip - prevIp;
if (compareChar != input[prevIp + bestLenIn])
{
return(result);
}
if (backward == 0 || backward > maxDistance)
{
return(result);
}
len = Match.DetermineLength(input, prevIp, ip, maxLength);
if (len >= 4)
{
int score = HasherSearchResult.BackwardReferenceScore(len, backward);
if (bestScore < score)
{
result.Len = len;
result.Score = score;
result.Distance = backward;
return(result);
}
}
return(result);
}
