public static bool Probe(ulong zkey, int depth, int alpha, int beta, ref int ttMove, ref int score)
{
if (0 == hashEntries)
{
return(false);
}
int hash = GetHash(zkey);
unsafe
{
HashTableEntry *h = (HashTableEntry *)hashTable;
if (KeyConfirm(h, hash, zkey))
{
if (h[hash].Depth >= depth)
{
ttMove = (int)(h[hash].Payload & 0xFFFFFFFFUL);
int val = (int)(h[hash].Payload >> 32);
if (h[hash].Type == HashTableEntry.ExactType)
{
score = val;
return(true);
}
if (h[hash].Type == HashTableEntry.AlphaType && (val <= alpha))
{
score = alpha;
return(true);
}
if (h[hash].Type == HashTableEntry.BetaType && (val >= beta))
{
score = beta;
return(true);
}
return(false);
}
else
{
return(false);
}
}
else
{
return(false);
}
}
}
public static void StoreMovesCount(ulong zkey, ulong moves, int depth)
{
if (0 == hashEntries)
{
return;
}
int hash = GetHash(zkey);
unsafe
{
HashTableEntry *h = (HashTableEntry *)hashTable;
h[hash].Payload = moves;
h[hash].Type = HashTableEntry.MoveCountType;
h[hash].Key = zkey;
h[hash].Depth = (byte)depth;
}
}
public static void Save(ulong zkey, int depth, int score, byte type, int move)
{
if (0 == hashEntries)
{
return;
}
int hash = GetHash(zkey);
unsafe
{
HashTableEntry *h = (HashTableEntry *)hashTable;
h[hash].Payload = (ulong)(((ulong)score << 32) | (uint)move);
h[hash].Type = type;
h[hash].Key = zkey;
h[hash].Depth = (byte)depth;
}
}
public static bool ProbeMovesCount(ulong zkey, out ulong moves, int depth)
{
if (0 == hashEntries)
{
moves = 0;
return(false);
}
int hash = GetHash(zkey);
unsafe
{
HashTableEntry *h = (HashTableEntry *)hashTable;
if (KeyConfirm(h, hash, zkey) && 0 != (h[hash].Type & HashTableEntry.MoveCountType) && h[hash].Depth == depth)
{
moves = h[hash].Payload;
return(true);
}
else
{
moves = 0;
return(false);
}
}
}
private static unsafe bool KeyConfirm(HashTableEntry *h, int hash, ulong zkey)
{
return(h[hash].Key == (zkey & ~HashTableEntry.KeyMask));
}