Value qsearch(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth);
void id_loop(Position& pos);
- bool check_is_dangerous(Position &pos, Move move, Value futilityBase, Value beta, Value *bValue);
+ bool check_is_dangerous(Position &pos, Move move, Value futilityBase, Value beta);
bool connected_moves(const Position& pos, Move m1, Move m2);
Value value_to_tt(Value v, int ply);
Value value_from_tt(Value v, int ply);
StateInfo st;
const TTEntry *tte;
Key posKey;
- Move ttMove, move, excludedMove, threatMove;
+ Move ttMove, move, excludedMove, bestMove, threatMove;
Depth ext, newDepth;
Bound bt;
Value bestValue, value, oldAlpha;
tte = NULL;
ttMove = excludedMove = MOVE_NONE;
sp = ss->sp;
+ bestMove = sp->bestMove;
threatMove = sp->threatMove;
bestValue = sp->bestValue;
moveCount = sp->moveCount; // Lock must be held here
}
else
{
- ss->currentMove = ss->bestMove = threatMove = (ss+1)->excludedMove = MOVE_NONE;
+ ss->currentMove = threatMove = (ss+1)->excludedMove = bestMove = MOVE_NONE;
(ss+1)->skipNullMove = false; (ss+1)->reduction = DEPTH_ZERO;
(ss+2)->killers[0] = (ss+2)->killers[1] = MOVE_NONE;
: can_return_tt(tte, depth, beta, ss->ply)))
{
TT.refresh(tte);
- ss->bestMove = move = ttMove; // Can be MOVE_NONE
+ ss->currentMove = ttMove; // Can be MOVE_NONE
value = value_from_tt(tte->value(), ss->ply);
if ( value >= beta
- && move
- && !pos.is_capture_or_promotion(move)
- && move != ss->killers[0])
+ && ttMove
+ && !pos.is_capture_or_promotion(ttMove)
+ && ttMove != ss->killers[0])
{
ss->killers[1] = ss->killers[0];
- ss->killers[0] = move;
+ ss->killers[0] = ttMove;
}
return value;
}
// move which was reduced. If a connection is found, return a fail
// low score (which will cause the reduced move to fail high in the
// parent node, which will trigger a re-search with full depth).
- threatMove = (ss+1)->bestMove;
+ threatMove = (ss+1)->currentMove;
if ( depth < ThreatDepth
&& (ss-1)->reduction
assert(rdepth >= ONE_PLY);
assert((ss-1)->currentMove != MOVE_NONE);
+ assert((ss-1)->currentMove != MOVE_NULL);
MovePicker mp(pos, ttMove, H, pos.captured_piece_type());
CheckInfo ci(pos);
MovePickerExt<SpNode> mp(pos, ttMove, depth, H, ss, PvNode ? -VALUE_INFINITE : beta);
CheckInfo ci(pos);
- ss->bestMove = MOVE_NONE;
futilityBase = ss->eval + ss->evalMargin;
singularExtensionNode = !RootNode
&& !SpNode
value = search<NonPV>(pos, ss, rBeta - 1, rBeta, depth / 2);
ss->skipNullMove = false;
ss->excludedMove = MOVE_NONE;
- ss->bestMove = MOVE_NONE;
if (value < rBeta)
ext = ONE_PLY;
}
if (value > bestValue)
{
bestValue = value;
- ss->bestMove = move;
+ bestMove = move;
if ( PvNode
&& value > alpha
if (SpNode && !thread.cutoff_occurred())
{
sp->bestValue = value;
- sp->ss->bestMove = move;
+ sp->bestMove = move;
sp->alpha = alpha;
if (value >= beta)
&& Threads.available_slave_exists(pos.thread())
&& !Signals.stop
&& !thread.cutoff_occurred())
- bestValue = Threads.split<FakeSplit>(pos, ss, alpha, beta, bestValue, depth,
- threatMove, moveCount, &mp, NT);
+ bestValue = Threads.split<FakeSplit>(pos, ss, alpha, beta, bestValue, &bestMove,
+ depth, threatMove, moveCount, &mp, NT);
}
// Step 20. Check for mate and stalemate
{
assert(!playedMoveCount);
- bestValue = alpha;
+ bestValue = oldAlpha;
}
// Step 21. Update tables
// Update transposition table entry, killers and history
if (!SpNode && !Signals.stop && !thread.cutoff_occurred())
{
- move = bestValue <= oldAlpha ? MOVE_NONE : ss->bestMove;
+ move = bestValue <= oldAlpha ? MOVE_NONE : bestMove;
bt = bestValue <= oldAlpha ? BOUND_UPPER
: bestValue >= beta ? BOUND_LOWER : BOUND_EXACT;
assert(pos.thread() >= 0 && pos.thread() < Threads.size());
StateInfo st;
- Move ttMove, move;
+ Move ttMove, move, bestMove;
Value bestValue, value, evalMargin, futilityValue, futilityBase;
bool inCheck, enoughMaterial, givesCheck, evasionPrunable;
const TTEntry* tte;
Bound bt;
Value oldAlpha = alpha;
- ss->bestMove = ss->currentMove = MOVE_NONE;
+ ss->currentMove = bestMove = MOVE_NONE;
ss->ply = (ss-1)->ply + 1;
// Check for an instant draw or maximum ply reached
if (!PvNode && tte && can_return_tt(tte, ttDepth, beta, ss->ply))
{
- ss->bestMove = ttMove; // Can be MOVE_NONE
+ ss->currentMove = ttMove; // Can be MOVE_NONE
return value_from_tt(tte->value(), ss->ply);
}
&& move != ttMove
&& !pos.is_capture_or_promotion(move)
&& ss->eval + PawnValueMidgame / 4 < beta
- && !check_is_dangerous(pos, move, futilityBase, beta, &bestValue))
+ && !check_is_dangerous(pos, move, futilityBase, beta))
continue;
// Check for legality only before to do the move
if (value > bestValue)
{
bestValue = value;
- ss->bestMove = move;
+ bestMove = move;
if ( PvNode
&& value > alpha
return mated_in(ss->ply); // Plies to mate from the root
// Update transposition table
- move = bestValue <= oldAlpha ? MOVE_NONE : ss->bestMove;
+ move = bestValue <= oldAlpha ? MOVE_NONE : bestMove;
bt = bestValue <= oldAlpha ? BOUND_UPPER
: bestValue >= beta ? BOUND_LOWER : BOUND_EXACT;
// bestValue is updated only when returning false because in that case move
// will be pruned.
- bool check_is_dangerous(Position &pos, Move move, Value futilityBase, Value beta, Value *bestValue)
+ bool check_is_dangerous(Position &pos, Move move, Value futilityBase, Value beta)
{
Bitboard b, occ, oldAtt, newAtt, kingAtt;
- Square from, to, ksq, victimSq;
+ Square from, to, ksq;
Piece pc;
Color them;
- Value futilityValue, bv = *bestValue;
from = from_sq(move);
to = to_sq(move);
them = ~pos.side_to_move();
ksq = pos.king_square(them);
kingAtt = pos.attacks_from<KING>(ksq);
- pc = pos.piece_on(from);
+ pc = pos.piece_moved(move);
occ = pos.occupied_squares() & ~(1ULL << from) & ~(1ULL << ksq);
oldAtt = pos.attacks_from(pc, from, occ);
// Rule 3. Creating new double threats with checks
b = pos.pieces(them) & newAtt & ~oldAtt & ~(1ULL << ksq);
-
while (b)
{
- victimSq = pop_1st_bit(&b);
- futilityValue = futilityBase + PieceValueEndgame[pos.piece_on(victimSq)];
-
// Note that here we generate illegal "double move"!
- if ( futilityValue >= beta
- && pos.see_sign(make_move(from, victimSq)) >= 0)
+ if (futilityBase + PieceValueEndgame[pos.piece_on(pop_1st_bit(&b))] >= beta)
return true;
-
- if (futilityValue > bv)
- bv = futilityValue;
}
- // Update bestValue only if check is not dangerous (because we will prune the move)
- *bestValue = bv;
return false;
}
Threads[master].wake_up();
}
}
- // In helpful master concept a master can help only a sub-tree of its split
- // point, and because here is all finished is not possible master is booked.
- assert(!is_searching);
}