Exemple #1
0
void
TranspositionTable::insert(U64 key, const Move& sm, int type, int ply, int depth, int evalScore) {
    if (depth < 0) depth = 0;
    size_t idx0 = getIndex(key);
    U64 key2 = getStoredKey(key);
    TTEntry ent0, ent1;
    ent0.load(table[idx0]);
    size_t idx = idx0;
    TTEntry* ent = &ent0;
    if (ent0.getKey() != key2) {
        size_t idx1 = idx0 ^ 1;
        ent1.load(table[idx1]);
        idx = idx1;
        ent = &ent1;
        if (ent1.getKey() != key2)
            if (ent1.betterThan(ent0, generation)) {
                idx = idx0;
                ent = &ent0;
            }
    }
    bool doStore = true;
    if ((ent->getKey() == key2) && (ent->getDepth() > depth) && (ent->getType() == type)) {
        if (type == TType::T_EXACT)
            doStore = false;
        else if ((type == TType::T_GE) && (sm.score() <= ent->getScore(ply)))
            doStore = false;
        else if ((type == TType::T_LE) && (sm.score() >= ent->getScore(ply)))
            doStore = false;
    }
    if (doStore) {
        if ((ent->getKey() != key2) || (sm.from() != sm.to()))
            ent->setMove(sm);
        ent->setKey(key2);
        ent->setScore(sm.score(), ply);
        ent->setDepth(depth);
        ent->setGeneration((S8)generation);
        ent->setType(type);
        ent->setEvalScore(evalScore);
        ent->store(table[idx]);
    }
}
Exemple #2
0
// Transposition Table look up + alpha/beta update
TTLookupValue AlphaBeta::TTlookup(const GameState & state, AlphaBetaScore & alpha, AlphaBetaScore & beta, const size_t & depth)
{
	TTEntry * entry = _TT->lookupScan(state.calculateHash(0), state.calculateHash(1));
	if (entry && (entry->getDepth() == depth)) 
	{
		// get the value and type of the entry
		AlphaBetaScore TTvalue = entry->getScore();
		
		// set alpha and beta depending on the type of entry in the TT
		if (entry->getType() == TTEntry::LOWER)
		{
			if (TTvalue > alpha) 
			{
				alpha = TTvalue;
			}
		}
		else if (entry->getType() == TTEntry::UPPER) 
		{
			if (TTvalue < beta)
			{
				beta  = TTvalue;
			}
		} 
		else
		{
			printf("LOL\n");
			alpha = TTvalue;
			beta = TTvalue;
		}
		
		if (alpha >= beta) 
		{
			// this will be a cut
			_results.ttcuts++;
			return TTLookupValue(true, true, entry);
		}
		else
		{
			// found but no cut
			_results.ttFoundNoCut++;
			return TTLookupValue(true, false, entry);
		}
	}
	else if (entry)
	{
		_results.ttFoundLessDepth++;
		return TTLookupValue(true, false, entry);
	}

	return TTLookupValue(false, false, entry);
}