{
RootMoves.push_back(MOVE_NONE);
sync_cout << "info depth 0 score "
- << score_to_uci(RootPos.in_check() ? -VALUE_MATE : VALUE_DRAW)
+ << score_to_uci(RootPos.checkers() ? -VALUE_MATE : VALUE_DRAW)
<< sync_endl;
goto finalize;
if (Options["Contempt Factor"] && !Options["UCI_AnalyseMode"])
{
int cf = Options["Contempt Factor"] * PawnValueMg / 100; // From centipawns
- cf = cf * MaterialTable::game_phase(RootPos) / PHASE_MIDGAME; // Scale down with phase
+ cf = cf * Material::game_phase(RootPos) / PHASE_MIDGAME; // Scale down with phase
DrawValue[ RootColor] = VALUE_DRAW - Value(cf);
DrawValue[~RootColor] = VALUE_DRAW + Value(cf);
}
Key posKey;
Move ttMove, move, excludedMove, bestMove, threatMove;
Depth ext, newDepth;
- Value bestValue, value, ttValue, ttValueUpper;
+ Value bestValue, value, ttValue;
Value eval, nullValue, futilityValue;
bool inCheck, givesCheck, pvMove, singularExtensionNode;
- bool captureOrPromotion, dangerous, doFullDepthSearch;
+ bool captureOrPromotion, dangerous, doFullDepthSearch, threatExtension;
int moveCount, playedMoveCount;
// Step 1. Initialize node
Thread* thisThread = pos.this_thread();
moveCount = playedMoveCount = 0;
- inCheck = pos.in_check();
+ threatExtension = false;
+ inCheck = pos.checkers();
if (SpNode)
{
tte = TT.probe(posKey);
ttMove = RootNode ? RootMoves[PVIdx].pv[0] : tte ? tte->move() : MOVE_NONE;
ttValue = tte ? value_from_tt(tte->value(), ss->ply) : VALUE_NONE;
- ttValueUpper = tte ? value_from_tt(tte->value_upper(), ss->ply) : VALUE_NONE;
// At PV nodes we check for exact scores, while at non-PV nodes we check for
// a fail high/low. Biggest advantage at probing at PV nodes is to have a
// smooth experience in analysis mode. We don't probe at Root nodes otherwise
// we should also update RootMoveList to avoid bogus output.
- if (!RootNode && tte)
+ if ( !RootNode
+ && tte
+ && tte->depth() >= depth
+ && ttValue != VALUE_NONE // Only in case of TT access race
+ && ( PvNode ? tte->type() == BOUND_EXACT
+ : ttValue >= beta ? (tte->type() & BOUND_LOWER)
+ : (tte->type() & BOUND_UPPER)))
{
- // Fail High
- if ( (tte->type() & BOUND_LOWER)
- && ttValue >= beta
- && tte->depth() >= depth
- && ttValue != VALUE_NONE) // Only in case of TT access race
- {
- // Update killers, we assume ttMove caused a cut-off
- if ( ttMove
- && !pos.is_capture_or_promotion(ttMove)
- && ttMove != ss->killers[0])
- {
- ss->killers[1] = ss->killers[0];
- ss->killers[0] = ttMove;
- }
- TT.refresh(tte);
- ss->currentMove = ttMove; // Can be MOVE_NONE
- return ttValue;
- }
+ TT.refresh(tte);
+ ss->currentMove = ttMove; // Can be MOVE_NONE
- // Fail Low
- if ( (tte->type() & BOUND_UPPER)
- && ttValueUpper <= alpha
- && tte->depth_upper() >= depth
- && ttValueUpper != VALUE_NONE) // Only in case of TT access race
+ if ( ttValue >= beta
+ && ttMove
+ && !pos.is_capture_or_promotion(ttMove)
+ && ttMove != ss->killers[0])
{
- TT.refresh(tte);
- ss->currentMove = ttMove; // Can be MOVE_NONE
- return ttValueUpper;
+ ss->killers[1] = ss->killers[0];
+ ss->killers[0] = ttMove;
}
+ return ttValue;
}
// Step 5. Evaluate the position statically and update parent's gain statistics
// The null move failed low, which means that we may be faced with
// some kind of threat. If the previous move was reduced, check if
// the move that refuted the null move was somehow connected to the
- // 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).
+ // move which was reduced. If a connection is found extend moves that
+ // defend against threat.
threatMove = (ss+1)->currentMove;
if ( depth < 5 * ONE_PLY
&& (ss-1)->reduction
&& threatMove != MOVE_NONE
&& yields_to_threat(pos, (ss-1)->currentMove, threatMove))
- return beta - 1;
+ threatExtension = true;
}
}
if (PvNode && dangerous)
ext = ONE_PLY;
+ else if (threatExtension && prevents_threat(pos, move, threatMove))
+ ext = ONE_PLY;
+
else if (givesCheck && pos.see_sign(move) >= 0)
ext = ONE_PLY / 2;
// Step 19. Check for splitting the search
if ( !SpNode
&& depth >= Threads.min_split_depth()
- && bestValue < beta
&& Threads.available_slave_exists(thisThread))
{
+ assert(bestValue < beta);
+
bestValue = Threads.split<FakeSplit>(pos, ss, alpha, beta, bestValue, &bestMove,
depth, threatMove, moveCount, mp, NT);
if (bestValue >= beta)
const bool PvNode = (NT == PV);
assert(NT == PV || NT == NonPV);
- assert(InCheck == pos.in_check());
+ assert(InCheck == !!pos.checkers());
assert(alpha >= -VALUE_INFINITE && alpha < beta && beta <= VALUE_INFINITE);
assert(PvNode || (alpha == beta - 1));
assert(depth <= DEPTH_ZERO);
const TTEntry* tte;
Key posKey;
Move ttMove, move, bestMove;
- Value bestValue, value, ttValue, ttValueUpper, futilityValue, futilityBase, oldAlpha;
+ Value bestValue, value, ttValue, futilityValue, futilityBase, oldAlpha;
bool givesCheck, enoughMaterial, evasionPrunable, fromNull;
Depth ttDepth;
tte = TT.probe(posKey);
ttMove = tte ? tte->move() : MOVE_NONE;
ttValue = tte ? value_from_tt(tte->value(),ss->ply) : VALUE_NONE;
- ttValueUpper = tte ? value_from_tt(tte->value_upper(),ss->ply) : VALUE_NONE;
// Decide whether or not to include checks, this fixes also the type of
// TT entry depth that we are going to use. Note that in qsearch we use
// only two types of depth in TT: DEPTH_QS_CHECKS or DEPTH_QS_NO_CHECKS.
ttDepth = InCheck || depth >= DEPTH_QS_CHECKS ? DEPTH_QS_CHECKS
: DEPTH_QS_NO_CHECKS;
- if (tte)
+ if ( tte
+ && tte->depth() >= ttDepth
+ && ttValue != VALUE_NONE // Only in case of TT access race
+ && ( PvNode ? tte->type() == BOUND_EXACT
+ : ttValue >= beta ? (tte->type() & BOUND_LOWER)
+ : (tte->type() & BOUND_UPPER)))
{
- // Fail High
- if ( (tte->type() & BOUND_LOWER)
- && ttValue >= beta
- && tte->depth() >= ttDepth
- && ttValue != VALUE_NONE) // Only in case of TT access race
- {
- ss->currentMove = ttMove; // Can be MOVE_NONE
- return ttValue;
- }
-
- // Fail Low
- if ( (tte->type() & BOUND_UPPER)
- && ttValueUpper <= alpha
- && tte->depth_upper() >= ttDepth
- && ttValueUpper != VALUE_NONE) // Only in case of TT access race
- {
- ss->currentMove = ttMove; // Can be MOVE_NONE
- return ttValueUpper;
- }
+ ss->currentMove = ttMove; // Can be MOVE_NONE
+ return ttValue;
}
// Evaluate the position statically
do {
pv.push_back(m);
- assert(pos.move_is_legal(pv[ply]));
+ assert(MoveList<LEGAL>(pos).contains(pv[ply]));
+
pos.do_move(pv[ply++], *st++);
tte = TT.probe(pos.key());
if (!tte || tte->move() != pv[ply]) // Don't overwrite correct entries
TT.store(pos.key(), VALUE_NONE, BOUND_NONE, DEPTH_NONE, pv[ply]);
- assert(pos.move_is_legal(pv[ply]));
+ assert(MoveList<LEGAL>(pos).contains(pv[ply]));
+
pos.do_move(pv[ply++], *st++);
} while (pv[ply] != MOVE_NONE);
projects / stockfish / blobdiff