const Depth RazorDepth = 4 * ONE_PLY;
// Dynamic razoring margin based on depth
- inline Value razor_margin(Depth d) { return Value(0x200 + 0x10 * int(d)); }
+ inline Value razor_margin(Depth d) { return Value(512 + 16 * int(d)); }
// Maximum depth for use of dynamic threat detection when null move fails low
const Depth ThreatDepth = 5 * ONE_PLY;
// At Non-PV nodes we do an internal iterative deepening search
// when the static evaluation is bigger then beta - IIDMargin.
- const Value IIDMargin = Value(0x100);
+ const Value IIDMargin = Value(256);
// Minimum depth for use of singular extension
const Depth SingularExtensionDepth[] = { 8 * ONE_PLY, 6 * ONE_PLY };
// Futility margin for quiescence search
- const Value FutilityMarginQS = Value(0x80);
+ const Value FutilityMarginQS = Value(128);
// Futility lookup tables (initialized at startup) and their access functions
Value FutilityMargins[16][64]; // [depth][moveNumber]
}
// Test for a capture that triggers a pawn endgame
- if ( captureOrPromotion
- && type_of(pos.piece_on(to_sq(m))) != PAWN
+ if ( captureOrPromotion
+ && type_of(pos.piece_on(to_sq(m))) != PAWN
+ && !is_special(m)
&& ( pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK)
- - PieceValueMidgame[pos.piece_on(to_sq(m))] == VALUE_ZERO)
- && !is_special(m))
+ - PieceValueMidgame[pos.piece_on(to_sq(m))] == VALUE_ZERO))
return true;
return false;
TT.refresh(tte);
ss->currentMove = ttMove; // Can be MOVE_NONE
- if ( ttValue >= beta
- && ttMove
+ if ( ttValue >= beta
+ && ttMove
&& !pos.is_capture_or_promotion(ttMove)
- && ttMove != ss->killers[0])
+ && ttMove != ss->killers[0])
{
ss->killers[1] = ss->killers[0];
ss->killers[0] = ttMove;
// Update gain for the parent non-capture move given the static position
// evaluation before and after the move.
- if ( (move = (ss-1)->currentMove) != MOVE_NULL
- && (ss-1)->eval != VALUE_NONE
- && ss->eval != VALUE_NONE
+ if ( (move = (ss-1)->currentMove) != MOVE_NULL
+ && (ss-1)->eval != VALUE_NONE
+ && ss->eval != VALUE_NONE
&& !pos.captured_piece_type()
&& !is_special(move))
{
futilityBase = ss->eval + ss->evalMargin;
singularExtensionNode = !RootNode
&& !SpNode
- && depth >= SingularExtensionDepth[PvNode]
- && ttMove != MOVE_NONE
+ && depth >= SingularExtensionDepth[PvNode]
+ && ttMove != MOVE_NONE
&& !excludedMove // Recursive singular search is not allowed
&& (tte->type() & BOUND_LOWER)
- && tte->depth() >= depth - 3 * ONE_PLY;
+ && tte->depth() >= depth - 3 * ONE_PLY;
// Step 11. Loop through moves
// Loop through all pseudo-legal moves until no moves remain or a beta cutoff occurs
- while ( bestValue < beta
+ while ( bestValue < beta
&& (move = mp.next_move()) != MOVE_NONE
&& !thisThread->cutoff_occurred()
&& !Signals.stop)
ext = ONE_PLY;
else if (givesCheck && pos.see_sign(move) >= 0)
- ext = PvNode ? ONE_PLY : ONE_PLY / 2;
+ ext = ONE_PLY / 2;
// Singular extension search. If all moves but one fail low on a search of
// (alpha-s, beta-s), and just one fails high on (alpha, beta), then that move
// is singular and should be extended. To verify this we do a reduced search
// on all the other moves but the ttMove, if result is lower than ttValue minus
// a margin then we extend ttMove.
- if ( singularExtensionNode
+ if ( singularExtensionNode
&& !ext
- && move == ttMove
- && pos.pl_move_is_legal(move, ci.pinned))
+ && move == ttMove
+ && pos.pl_move_is_legal(move, ci.pinned))
{
if (abs(ttValue) < VALUE_KNOWN_WIN)
{
// Step 15. Reduced depth search (LMR). If the move fails high will be
// re-searched at full depth.
- if ( depth > 3 * ONE_PLY
+ if ( depth > 3 * ONE_PLY
&& !isPvMove
&& !captureOrPromotion
&& !dangerous
// Step 19. Check for split
if ( !SpNode
- && depth >= Threads.min_split_depth()
- && bestValue < beta
- && Threads.available_slave_exists(thisThread)
+ && depth >= Threads.min_split_depth()
+ && depth - reduction<PvNode>(depth, moveCount) >= Threads.min_split_depth()
+ && bestValue < beta
+ && Threads.available_slave_exists(thisThread)
&& !Signals.stop
&& !thisThread->cutoff_occurred())
bestValue = Threads.split<FakeSplit>(pos, ss, alpha, beta, bestValue, &bestMove,
// Detect non-capture evasions that are candidate to be pruned
evasionPrunable = !PvNode
- && inCheck
- && bestValue > VALUE_MATED_IN_MAX_PLY
+ && inCheck
+ && bestValue > VALUE_MATED_IN_MAX_PLY
&& !pos.is_capture(move)
&& !pos.can_castle(pos.side_to_move());
// Rule 1. Checks which give opponent's king at most one escape square are dangerous
b = kingAtt & ~pos.pieces(them) & ~newAtt & ~(1ULL << to);
- if (single_bit(b)) // Catches also !b
+ if (!more_than_one(b))
return true;
// Rule 2. Queen contact check is very dangerous
// Case 3: Moving through the vacated square
p2 = pos.piece_on(f2);
- if (piece_is_slider(p2) && (squares_between(f2, t2) & f1))
+ if (piece_is_slider(p2) && (between_bb(f2, t2) & f1))
return true;
// Case 4: The destination square for m2 is defended by the moving piece in m1
// Case 5: Discovered check, checking piece is the piece moved in m1
ksq = pos.king_square(pos.side_to_move());
if ( piece_is_slider(p1)
- && (squares_between(t1, ksq) & f2)
+ && (between_bb(t1, ksq) & f2)
&& (pos.attacks_from(p1, t1, pos.pieces() ^ f2) & ksq))
return true;
// Case 3: If the moving piece in the threatened move is a slider, don't
// prune safe moves which block its ray.
if ( piece_is_slider(pos.piece_on(tfrom))
- && (squares_between(tfrom, tto) & mto)
+ && (between_bb(tfrom, tto) & mto)
&& pos.see_sign(m) >= 0)
return true;
// Wake up master thread so to allow it to return from the idle loop in
// case we are the last slave of the split point.
- if ( Threads.use_sleeping_threads()
- && this != sp->master
+ if ( Threads.use_sleeping_threads()
+ && this != sp->master
&& !sp->master->is_searching)
sp->master->wake_up();
// our feet by the sp master. Also accessing other Thread objects is
// unsafe because if we are exiting there is a chance are already freed.
lock_release(sp->lock);
-
- // Try to reparent to another split point. Only for slave threads
- // that are not master of any active split point.
- if (!splitPointsCnt)
- for (int i = 0; i < Threads.size(); i++)
- {
- Thread* th = &Threads[i];
- SplitPoint* oldest = &th->splitPoints[0];
-
- // Find the first split point with still all slaves running
- // where we are available as a possible slave.
- if ( !is_searching
- && th->splitPointsCnt
- && !oldest->cutoff
- && oldest->slavesMask == oldest->allSlavesMask
- && !single_bit(oldest->allSlavesMask))
- {
- lock_grab(oldest->lock);
- lock_grab(Threads.splitLock);
-
- // Retest all under lock protection, we are in the middle
- // of a race storm here !
- if ( !is_searching
- && th->splitPointsCnt
- && !oldest->cutoff
- && oldest->slavesMask == oldest->allSlavesMask
- && !single_bit(oldest->allSlavesMask))
- {
- oldest->slavesMask |= 1ULL << idx; // allSlavesMask is not updated
- curSplitPoint = oldest;
- is_searching = true;
- }
-
- lock_release(Threads.splitLock);
- lock_release(oldest->lock);
-
- break; // Exit anyhow, only one try (enough in 99% of cases)
- }
- }
}
}
}
projects / stockfish / blobdiff