public static ulong ComputeHash(byte[] input)
{
uint len = (uint)input.Length;
uint num_chunks = len / 128;
// copy tail, pad with zeroes
byte[] tail = new byte[128];
uint tail_size = len % 128;
Array.Copy(input, len - tail_size, tail, 0, tail_size);
UInt128 hash;
if (num_chunks != 0)
{
hash = HashChunk(input, 128, 0);
}
else
{
hash = HashChunk(tail, tail_size, 0);
}
hash += ROUND_MAGIC;
int offset = 0;
if (num_chunks != 0)
{
while (--num_chunks > 0)
{
offset += 128;
hash = HashMulAdd(hash, ROUND_MAGIC, HashChunk(input, 128, offset));
}
if (tail_size > 0)
{
hash = HashMulAdd(hash, ROUND_MAGIC, HashChunk(tail, tail_size, 0));
}
}
hash += new UInt128(tail_size * 8, 0);
if (hash > new UInt128(0x7fffffffffffffff, 0xffffffffffffffff))
{
hash++;
}
hash = hash << 1 >> 1;
ulong X = hash.hi + (hash.lo >> 32);
X = ((X + (X >> 32) + 1) >> 32) + hash.hi;
ulong Y = (X << 32) + hash.lo;
ulong A = X + FINAL_MAGIC0;
if (A < X)
{
A += 0x101;
}
ulong B = Y + FINAL_MAGIC1;
if (B < Y)
{
B += 0x101;
}
UInt128 H = new UInt128(A) * B;
UInt128 mul = new UInt128(0x101);
H = (mul * H.hi) + H.lo;
H = (mul * H.hi) + H.lo;
if (H.hi > 0)
{
H += mul;
}
if (H.lo > 0xFFFFFFFFFFFFFEFE)
{
H += mul;
}
return(H.lo);
}
public bool Equals(UInt128 other)
{
return(hi == other.hi && lo == other.lo);
}