// Use internal iterative deepening?
const bool UseIIDAtPVNodes = true;
- const bool UseIIDAtNonPVNodes = false;
+ const bool UseIIDAtNonPVNodes = true;
// Internal iterative deepening margin. At Non-PV moves, when
// UseIIDAtNonPVNodes is true, we do an internal iterative deepening
// If the TT move is at least SingleReplyMargin better then the
// remaining ones we will extend it.
- const Value SingleReplyMargin = Value(0x64);
+ const Value SingleReplyMargin = Value(0x20);
// Margins for futility pruning in the quiescence search, and at frontier
// and near frontier nodes.
const Value FutilityMarginQS = Value(0x80);
// Each move futility margin is decreased
- const Value IncrementalFutilityMargin = Value(0x4);
+ const Value IncrementalFutilityMargin = Value(0x8);
// Razoring
const Depth RazorDepth = 4*OnePly;
Depth ThreatDepth; // heavy SMP read access
// Last seconds noise filtering (LSN)
- const bool UseLSNFiltering = true;
+ const bool UseLSNFiltering = false;
const int LSNTime = 4000; // In milliseconds
const Value LSNValue = value_from_centipawns(200);
bool loseOnTime = false;
bool move_is_killer(Move m, const SearchStack& ss);
Depth extension(const Position& pos, Move m, bool pvNode, bool capture, bool check, bool singleReply, bool mateThreat, bool* dangerous);
bool ok_to_do_nullmove(const Position& pos);
- bool ok_to_prune(const Position& pos, Move m, Move threat, Depth d);
+ bool ok_to_prune(const Position& pos, Move m, Move threat);
bool ok_to_use_TT(const TTEntry* tte, Depth depth, Value beta, int ply);
void update_history(const Position& pos, Move m, Depth depth, Move movesSearched[], int moveCount);
void update_killers(Move m, SearchStack& ss);
{
Move bookMove;
if (get_option_value_string("Book File") != OpeningBook.file_name())
- OpeningBook.open("book.bin");
+ OpeningBook.open(get_option_value_string("Book File"));
bookMove = OpeningBook.get_move(pos);
if (bookMove != MOVE_NONE)
Problem = false;
ExactMaxTime = maxTime;
+ if (button_was_pressed("New Game"))
+ loseOnTime = false; // reset at the beginning of a new game
+
// Read UCI option values
TT.set_size(get_option_value_int("Hash"));
if (button_was_pressed("Clear Hash"))
- {
TT.clear();
- loseOnTime = false; // reset at the beginning of a new game
- }
bool PonderingEnabled = get_option_value_bool("Ponder");
MultiPV = get_option_value_int("MultiPV");
// searchMoves are verified, copied, scored and sorted
RootMoveList rml(p, searchMoves);
+ if (rml.move_count() == 0)
+ {
+ if (PonderSearch)
+ wait_for_stop_or_ponderhit();
+
+ return pos.is_check()? -VALUE_MATE : VALUE_DRAW;
+ }
+
// Print RootMoveList c'tor startup scoring to the standard output,
// so that we print information also for iteration 1.
std::cout << "info depth " << 1 << "\ninfo depth " << 1
// Go with internal iterative deepening if we don't have a TT move
if (UseIIDAtNonPVNodes && ttMove == MOVE_NONE && depth >= 8*OnePly &&
- evaluate(pos, ei, threadID) >= beta - IIDMargin)
+ !isCheck && evaluate(pos, ei, threadID) >= beta - IIDMargin)
{
search(pos, ss, beta, Min(depth/2, depth-2*OnePly), ply, false, threadID);
ttMove = ss[ply].pv[ply];
&& !captureOrPromotion
&& move != ttMove)
{
- // History pruning. See ok_to_prune() definition
+ // Move count based pruning
if ( moveCount >= FutilityMoveCountMargin
- && ok_to_prune(pos, move, ss[ply].threatMove, depth)
+ && ok_to_prune(pos, move, ss[ply].threatMove)
&& bestValue > value_mated_in(PLY_MAX))
continue;
// Value based pruning
- if (approximateEval < beta)
- {
- if (futilityValue == VALUE_NONE)
- futilityValue = evaluate(pos, ei, threadID) + FutilityValueMargin;
+ if (futilityValue == VALUE_NONE)
+ futilityValue = evaluate(pos, ei, threadID) + FutilityValueMargin;
- futilityValueScaled = futilityValue - moveCount * IncrementalFutilityMargin;
+ futilityValueScaled = futilityValue - moveCount * IncrementalFutilityMargin;
- if (futilityValueScaled < beta)
- {
- if (futilityValueScaled > bestValue)
- bestValue = futilityValueScaled;
- continue;
- }
+ if (futilityValueScaled < beta)
+ {
+ if (futilityValueScaled > bestValue)
+ bestValue = futilityValueScaled;
+ continue;
}
}
bool useFutilityPruning = sp->depth < SelectiveDepth
&& !isCheck;
+ const int FutilityMoveCountMargin = 3 + (1 << (3 * int(sp->depth) / 8));
const int FutilityValueMargin = 112 * bitScanReverse32(int(sp->depth) * int(sp->depth) / 2);
while ( sp->bestValue < sp->beta
&& !dangerous
&& !captureOrPromotion)
{
- // History pruning. See ok_to_prune() definition
- if ( moveCount >= 2 + int(sp->depth)
- && ok_to_prune(pos, move, ss[sp->ply].threatMove, sp->depth)
+ // Move count based pruning
+ if ( moveCount >= FutilityMoveCountMargin
+ && ok_to_prune(pos, move, ss[sp->ply].threatMove)
&& sp->bestValue > value_mated_in(PLY_MAX))
continue;
// Value based pruning
- if (sp->approximateEval < sp->beta)
+ if (sp->futilityValue == VALUE_NONE)
{
- if (sp->futilityValue == VALUE_NONE)
- {
- EvalInfo ei;
- sp->futilityValue = evaluate(pos, ei, threadID) + FutilityValueMargin;
- }
+ EvalInfo ei;
+ sp->futilityValue = evaluate(pos, ei, threadID) + FutilityValueMargin;
+ }
- if (sp->futilityValue < sp->beta)
+ Value futilityValueScaled = sp->futilityValue - moveCount * IncrementalFutilityMargin;
+
+ if (futilityValueScaled < sp->beta)
+ {
+ if (futilityValueScaled > sp->bestValue) // Less then 1% of cases
{
- if (sp->futilityValue > sp->bestValue) // Less then 1% of cases
- {
- lock_grab(&(sp->lock));
- if (sp->futilityValue > sp->bestValue)
- sp->bestValue = sp->futilityValue;
- lock_release(&(sp->lock));
- }
- continue;
+ lock_grab(&(sp->lock));
+ if (futilityValueScaled > sp->bestValue)
+ sp->bestValue = futilityValueScaled;
+ lock_release(&(sp->lock));
}
+ continue;
}
}
// non-tactical moves late in the move list close to the leaves are
// candidates for pruning.
- bool ok_to_prune(const Position& pos, Move m, Move threat, Depth d) {
+ bool ok_to_prune(const Position& pos, Move m, Move threat) {
assert(move_is_ok(m));
assert(threat == MOVE_NONE || move_is_ok(threat));
assert(!pos.move_is_check(m));
assert(!pos.move_is_capture_or_promotion(m));
assert(!pos.move_is_passed_pawn_push(m));
- assert(d >= OnePly);
Square mfrom, mto, tfrom, tto;
&& pos.move_attacks_square(m, tto))
return false;
- // Case 4: Don't prune moves with good history
- if (!H.ok_to_prune(pos.piece_on(mfrom), mto, d))
- return false;
-
- // Case 5: If the moving piece in the threatened move is a slider, don't
+ // Case 4: If the moving piece in the threatened move is a slider, don't
// prune safe moves which block its ray.
if ( !PruneBlockingMoves
&& threat != MOVE_NONE
Value v = value_from_tt(tte->value(), ply);
return ( tte->depth() >= depth
- || v >= Max(value_mate_in(100), beta)
- || v < Min(value_mated_in(100), beta))
+ || v >= Max(value_mate_in(PLY_MAX), beta)
+ || v < Min(value_mated_in(PLY_MAX), beta))
&& ( (is_lower_bound(tte->type()) && v >= beta)
|| (is_upper_bound(tte->type()) && v < beta));
{
assert(m != movesSearched[i]);
if (!pos.move_is_capture_or_promotion(movesSearched[i]))
- H.failure(pos.piece_on(move_from(movesSearched[i])), move_to(movesSearched[i]));
+ H.failure(pos.piece_on(move_from(movesSearched[i])), move_to(movesSearched[i]), depth);
}
}
projects / stockfish / blobdiff