#include <cassert>
#include <cmath>
#include <cstring>
-#include <fstream>
+#include <iomanip>
#include <iostream>
#include <sstream>
#include <vector>
using std::cout;
using std::endl;
+using std::string;
namespace {
const bool FakeSplit = false;
// Different node types, used as template parameter
- enum NodeType { Root, PV, NonPV, SplitPointPV, SplitPointNonPV };
+ enum NodeType { Root, PV, NonPV, SplitPointRoot, SplitPointPV, SplitPointNonPV };
// RootMove struct is used for moves at the root of the tree. For each root
- // move, we store two scores, a node count, and a PV (really a refutation
- // in the case of moves which fail low). Value pv_score is normally set at
- // -VALUE_INFINITE for all non-pv moves, while non_pv_score is computed
- // according to the order in which moves are returned by MovePicker.
+ // move, we store a score, a node count, and a PV (really a refutation
+ // in the case of moves which fail low). Score is normally set at
+ // -VALUE_INFINITE for all non-pv moves.
struct RootMove {
- RootMove();
- RootMove(const RootMove& rm) { *this = rm; }
- RootMove& operator=(const RootMove& rm);
-
// RootMove::operator<() is the comparison function used when
// sorting the moves. A move m1 is considered to be better
- // than a move m2 if it has an higher pv_score, or if it has
- // equal pv_score but m1 has the higher non_pv_score. In this way
- // we are guaranteed that PV moves are always sorted as first.
- bool operator<(const RootMove& m) const {
- return pv_score != m.pv_score ? pv_score < m.pv_score
- : non_pv_score < m.non_pv_score;
- }
+ // than a move m2 if it has an higher score
+ bool operator<(const RootMove& m) const { return score < m.score; }
void extract_pv_from_tt(Position& pos);
void insert_pv_in_tt(Position& pos);
int64_t nodes;
- Value pv_score;
- Value non_pv_score;
- Move pv[PLY_MAX_PLUS_2];
+ Value score;
+ Value prevScore;
+ std::vector<Move> pv;
};
// RootMoveList struct is mainly a std::vector of RootMove objects
struct RootMoveList : public std::vector<RootMove> {
+
void init(Position& pos, Move searchMoves[]);
+ RootMove* find(const Move& m, int startIndex = 0);
+
int bestMoveChanges;
};
RootMoveList Rml;
// MultiPV mode
- int MultiPV, UCIMultiPV;
+ int MultiPV, UCIMultiPV, MultiPVIdx;
// Time management variables
bool StopOnPonderhit, FirstRootMove, StopRequest, QuitRequest, AspirationFailLow;
TimeManager TimeMgr;
SearchLimits Limits;
- // Log file
- std::ofstream LogFile;
-
// Skill level adjustment
int SkillLevel;
bool SkillLevelEnabled;
// Node counters, used only by thread[0] but try to keep in different cache
// lines (64 bytes each) from the heavy multi-thread read accessed variables.
- bool SendSearchedNodes;
int NodesSincePoll;
int NodesBetweenPolls = 30000;
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);
- bool ok_to_use_TT(const TTEntry* tte, Depth depth, Value beta, int ply);
+ bool can_return_tt(const TTEntry* tte, Depth depth, Value beta, int ply);
bool connected_threat(const Position& pos, Move m, Move threat);
Value refine_eval(const TTEntry* tte, Value defaultEval, int ply);
void update_history(const Position& pos, Move move, Depth depth, Move movesSearched[], int moveCount);
void do_skill_level(Move* best, Move* ponder);
int current_search_time(int set = 0);
- std::string score_to_uci(Value v, Value alpha, Value beta);
- std::string speed_to_uci(int64_t nodes);
- std::string pv_to_uci(Move pv[], int pvNum);
- std::string depth_to_uci(Depth depth);
+ string score_to_uci(Value v, Value alpha = -VALUE_INFINITE, Value beta = VALUE_INFINITE);
+ string speed_to_uci(int64_t nodes);
+ string pv_to_uci(const Move pv[], int pvNum, bool chess960);
+ string pretty_pv(Position& pos, int depth, Value score, int time, Move pv[]);
+ string depth_to_uci(Depth depth);
void poll(const Position& pos);
void wait_for_stop_or_ponderhit();
// MovePickerExt template class extends MovePicker and allows to choose at compile
// time the proper moves source according to the type of node. In the default case
// we simply create and use a standard MovePicker object.
- template<NodeType> struct MovePickerExt : public MovePicker {
+ template<bool SpNode> struct MovePickerExt : public MovePicker {
MovePickerExt(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss, Value b)
: MovePicker(p, ttm, d, h, ss, b) {}
-
- RootMove& current() { assert(false); return Rml[0]; } // Dummy, needed to compile
};
// In case of a SpNode we use split point's shared MovePicker object as moves source
- template<> struct MovePickerExt<SplitPointNonPV> : public MovePickerExt<NonPV> {
+ template<> struct MovePickerExt<true> : public MovePicker {
MovePickerExt(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss, Value b)
- : MovePickerExt<NonPV>(p, ttm, d, h, ss, b), mp(ss->sp->mp) {}
+ : MovePicker(p, ttm, d, h, ss, b), mp(ss->sp->mp) {}
Move get_next_move() { return mp->get_next_move(); }
MovePicker* mp;
};
- template<> struct MovePickerExt<SplitPointPV> : public MovePickerExt<SplitPointNonPV> {
-
- MovePickerExt(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss, Value b)
- : MovePickerExt<SplitPointNonPV>(p, ttm, d, h, ss, b) {}
- };
-
- // In case of a Root node we use RootMoveList as moves source
- template<> struct MovePickerExt<Root> : public MovePicker {
-
- MovePickerExt(const Position&, Move, Depth, const History&, SearchStack*, Value);
- RootMove& current() { return Rml[cur]; }
- Move get_next_move() { return ++cur < (int)Rml.size() ? Rml[cur].pv[0] : MOVE_NONE; }
-
- int cur;
- };
-
// Overload operator<<() to make it easier to print moves in a coordinate
// notation compatible with UCI protocol.
std::ostream& operator<<(std::ostream& os, Move m) {
if (moveIsCheck && pos.see_sign(m) >= 0)
result += CheckExtension[PvNode];
- if (piece_type(pos.piece_on(move_from(m))) == PAWN)
+ if (type_of(pos.piece_on(move_from(m))) == PAWN)
{
Color c = pos.side_to_move();
if (relative_rank(c, move_to(m)) == RANK_7)
}
if ( captureOrPromotion
- && piece_type(pos.piece_on(move_to(m))) != PAWN
+ && type_of(pos.piece_on(move_to(m))) != PAWN
&& ( pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK)
- - piece_value_midgame(pos.piece_on(move_to(m))) == VALUE_ZERO)
- && !move_is_special(m))
+ - PieceValueMidgame[pos.piece_on(move_to(m))] == VALUE_ZERO)
+ && !is_special(m))
{
result += PawnEndgameExtension[PvNode];
*dangerous = true;
bool think(Position& pos, const SearchLimits& limits, Move searchMoves[]) {
- static Book book;
+ static Book book; // Define static to initialize the PRNG only once
// Initialize global search-related variables
- StopOnPonderhit = StopRequest = QuitRequest = AspirationFailLow = SendSearchedNodes = false;
+ StopOnPonderhit = StopRequest = QuitRequest = AspirationFailLow = false;
NodesSincePoll = 0;
current_search_time(get_system_time());
Limits = limits;
// Look for a book move
if (Options["OwnBook"].value<bool>())
{
- if (Options["Book File"].value<std::string>() != book.name())
- book.open(Options["Book File"].value<std::string>());
+ if (Options["Book File"].value<string>() != book.name())
+ book.open(Options["Book File"].value<string>());
- Move bookMove = book.get_move(pos, Options["Best Book Move"].value<bool>());
+ Move bookMove = book.probe(pos, Options["Best Book Move"].value<bool>());
if (bookMove != MOVE_NONE)
{
if (Limits.ponder)
read_evaluation_uci_options(pos.side_to_move());
Threads.read_uci_options();
- // If needed allocate pawn and material hash tables and adjust TT size
- Threads.init_hash_tables();
+ // Set a new TT size if changed
TT.set_size(Options["Hash"].value<int>());
if (Options["Clear Hash"].value<bool>())
// Write to log file and keep it open to be accessed during the search
if (Options["Use Search Log"].value<bool>())
{
- std::string name = Options["Search Log Filename"].value<std::string>();
- LogFile.open(name.c_str(), std::ios::out | std::ios::app);
-
- if (LogFile.is_open())
- LogFile << "\nSearching: " << pos.to_fen()
- << "\ninfinite: " << Limits.infinite
- << " ponder: " << Limits.ponder
- << " time: " << Limits.time
- << " increment: " << Limits.increment
- << " moves to go: " << Limits.movesToGo
- << endl;
+ Log log(Options["Search Log Filename"].value<string>());
+ log << "\nSearching: " << pos.to_fen()
+ << "\ninfinite: " << Limits.infinite
+ << " ponder: " << Limits.ponder
+ << " time: " << Limits.time
+ << " increment: " << Limits.increment
+ << " moves to go: " << Limits.movesToGo
+ << endl;
}
// We're ready to start thinking. Call the iterative deepening loop function
Move bestMove = id_loop(pos, searchMoves, &ponderMove);
// Write final search statistics and close log file
- if (LogFile.is_open())
+ if (Options["Use Search Log"].value<bool>())
{
int t = current_search_time();
- LogFile << "Nodes: " << pos.nodes_searched()
- << "\nNodes/second: " << (t > 0 ? pos.nodes_searched() * 1000 / t : 0)
- << "\nBest move: " << move_to_san(pos, bestMove);
+ Log log(Options["Search Log Filename"].value<string>());
+ log << "Nodes: " << pos.nodes_searched()
+ << "\nNodes/second: " << (t > 0 ? pos.nodes_searched() * 1000 / t : 0)
+ << "\nBest move: " << move_to_san(pos, bestMove);
StateInfo st;
pos.do_move(bestMove, st);
- LogFile << "\nPonder move: " << move_to_san(pos, ponderMove) << endl;
+ log << "\nPonder move: " << move_to_san(pos, ponderMove) << endl;
pos.undo_move(bestMove); // Return from think() with unchanged position
- LogFile.close();
}
// This makes all the threads to go to sleep
H.clear();
*ponderMove = bestMove = easyMove = skillBest = skillPonder = MOVE_NONE;
depth = aspirationDelta = 0;
- alpha = -VALUE_INFINITE, beta = VALUE_INFINITE;
+ value = alpha = -VALUE_INFINITE, beta = VALUE_INFINITE;
ss->currentMove = MOVE_NULL; // Hack to skip update_gains()
// Moves to search are verified and copied
// Iterative deepening loop until requested to stop or target depth reached
while (!StopRequest && ++depth <= PLY_MAX && (!Limits.maxDepth || depth <= Limits.maxDepth))
{
+ // Save now last iteration's scores, before Rml moves are reordered
+ for (size_t i = 0; i < Rml.size(); i++)
+ Rml[i].prevScore = Rml[i].score;
+
Rml.bestMoveChanges = 0;
- // Calculate dynamic aspiration window based on previous iterations
- if (MultiPV == 1 && depth >= 5 && abs(bestValues[depth - 1]) < VALUE_KNOWN_WIN)
+ // MultiPV loop. We perform a full root search for each PV line
+ for (MultiPVIdx = 0; MultiPVIdx < Min(MultiPV, (int)Rml.size()); MultiPVIdx++)
{
- int prevDelta1 = bestValues[depth - 1] - bestValues[depth - 2];
- int prevDelta2 = bestValues[depth - 2] - bestValues[depth - 3];
+ // Calculate dynamic aspiration window based on previous iterations
+ if (depth >= 5 && abs(Rml[MultiPVIdx].prevScore) < VALUE_KNOWN_WIN)
+ {
+ int prevDelta1 = bestValues[depth - 1] - bestValues[depth - 2];
+ int prevDelta2 = bestValues[depth - 2] - bestValues[depth - 3];
- aspirationDelta = Min(Max(abs(prevDelta1) + abs(prevDelta2) / 2, 16), 24);
- aspirationDelta = (aspirationDelta + 7) / 8 * 8; // Round to match grainSize
+ aspirationDelta = Min(Max(abs(prevDelta1) + abs(prevDelta2) / 2, 16), 24);
+ aspirationDelta = (aspirationDelta + 7) / 8 * 8; // Round to match grainSize
- alpha = Max(bestValues[depth - 1] - aspirationDelta, -VALUE_INFINITE);
- beta = Min(bestValues[depth - 1] + aspirationDelta, VALUE_INFINITE);
- }
-
- // Start with a small aspiration window and, in case of fail high/low,
- // research with bigger window until not failing high/low anymore.
- do {
- // Search starting from ss+1 to allow calling update_gains()
- value = search<Root>(pos, ss+1, alpha, beta, depth * ONE_PLY);
-
- // Write PV back to transposition table in case the relevant entries
- // have been overwritten during the search.
- for (int i = 0; i < Min(MultiPV, (int)Rml.size()); i++)
- Rml[i].insert_pv_in_tt(pos);
-
- // Value cannot be trusted. Break out immediately!
- if (StopRequest)
- break;
-
- // Send full PV info to GUI if we are going to leave the loop or
- // if we have a fail high/low and we are deep in the search.
- if ((value > alpha && value < beta) || current_search_time() > 2000)
- for (int i = 0; i < Min(UCIMultiPV, (int)Rml.size()); i++)
- cout << "info"
- << depth_to_uci(depth * ONE_PLY)
- << score_to_uci(Rml[i].pv_score, alpha, beta)
- << speed_to_uci(pos.nodes_searched())
- << pv_to_uci(Rml[i].pv, i + 1) << endl;
-
- // In case of failing high/low increase aspiration window and research,
- // otherwise exit the fail high/low loop.
- if (value >= beta)
- {
- beta = Min(beta + aspirationDelta, VALUE_INFINITE);
- aspirationDelta += aspirationDelta / 2;
+ alpha = Max(Rml[MultiPVIdx].prevScore - aspirationDelta, -VALUE_INFINITE);
+ beta = Min(Rml[MultiPVIdx].prevScore + aspirationDelta, VALUE_INFINITE);
}
- else if (value <= alpha)
+ else
{
- AspirationFailLow = true;
- StopOnPonderhit = false;
-
- alpha = Max(alpha - aspirationDelta, -VALUE_INFINITE);
- aspirationDelta += aspirationDelta / 2;
+ alpha = -VALUE_INFINITE;
+ beta = VALUE_INFINITE;
}
- else
- break;
- } while (abs(value) < VALUE_KNOWN_WIN);
+ // Start with a small aspiration window and, in case of fail high/low,
+ // research with bigger window until not failing high/low anymore.
+ do {
+ // Search starts from ss+1 to allow referencing (ss-1). This is
+ // needed by update_gains() and ss copy when splitting at Root.
+ value = search<Root>(pos, ss+1, alpha, beta, depth * ONE_PLY);
+
+ // Bring to front the best move. It is critical that sorting is
+ // done with a stable algorithm because all the values but the first
+ // and eventually the new best one are set to -VALUE_INFINITE and
+ // we want to keep the same order for all the moves but the new
+ // PV that goes to the front. Note that in case of MultiPV search
+ // the already searched PV lines are preserved.
+ sort<RootMove>(Rml.begin() + MultiPVIdx, Rml.end());
+
+ // In case we have found an exact score and we are going to leave
+ // the fail high/low loop then reorder the PV moves, otherwise
+ // leave the last PV move in its position so to be searched again.
+ // Of course this is needed only in MultiPV search.
+ if (MultiPVIdx && value > alpha && value < beta)
+ sort<RootMove>(Rml.begin(), Rml.begin() + MultiPVIdx);
+
+ // Write PV back to transposition table in case the relevant entries
+ // have been overwritten during the search.
+ for (int i = 0; i <= MultiPVIdx; i++)
+ Rml[i].insert_pv_in_tt(pos);
+
+ // If search has been stopped exit the aspiration window loop,
+ // note that sorting and writing PV back to TT is safe becuase
+ // Rml is still valid, although refers to the previous iteration.
+ if (StopRequest)
+ break;
+
+ // Send full PV info to GUI if we are going to leave the loop or
+ // if we have a fail high/low and we are deep in the search. UCI
+ // protocol requires to send all the PV lines also if are still
+ // to be searched and so refer to the previous search's score.
+ if ((value > alpha && value < beta) || current_search_time() > 2000)
+ for (int i = 0; i < Min(UCIMultiPV, (int)Rml.size()); i++)
+ {
+ bool updated = (i <= MultiPVIdx);
+
+ if (depth == 1 && !updated)
+ continue;
+
+ Depth d = (updated ? depth : depth - 1) * ONE_PLY;
+ Value s = (updated ? Rml[i].score : Rml[i].prevScore);
+
+ cout << "info"
+ << depth_to_uci(d)
+ << (i == MultiPVIdx ? score_to_uci(s, alpha, beta) : score_to_uci(s))
+ << speed_to_uci(pos.nodes_searched())
+ << pv_to_uci(&Rml[i].pv[0], i + 1, pos.is_chess960())
+ << endl;
+ }
+
+ // In case of failing high/low increase aspiration window and
+ // research, otherwise exit the fail high/low loop.
+ if (value >= beta)
+ {
+ beta = Min(beta + aspirationDelta, VALUE_INFINITE);
+ aspirationDelta += aspirationDelta / 2;
+ }
+ else if (value <= alpha)
+ {
+ AspirationFailLow = true;
+ StopOnPonderhit = false;
+
+ alpha = Max(alpha - aspirationDelta, -VALUE_INFINITE);
+ aspirationDelta += aspirationDelta / 2;
+ }
+ else
+ break;
+
+ } while (abs(value) < VALUE_KNOWN_WIN);
+ }
// Collect info about search result
bestMove = Rml[0].pv[0];
bestValues[depth] = value;
bestMoveChanges[depth] = Rml.bestMoveChanges;
- // Do we need to pick now the best and the ponder moves ?
+ // Skills: Do we need to pick now the best and the ponder moves ?
if (SkillLevelEnabled && depth == 1 + SkillLevel)
do_skill_level(&skillBest, &skillPonder);
- if (LogFile.is_open())
- LogFile << pretty_pv(pos, depth, value, current_search_time(), Rml[0].pv) << endl;
+ if (Options["Use Search Log"].value<bool>())
+ {
+ Log log(Options["Search Log Filename"].value<string>());
+ log << pretty_pv(pos, depth, value, current_search_time(), &Rml[0].pv[0]) << endl;
+ }
- // Init easyMove after first iteration or drop if differs from the best move
- if (depth == 1 && (Rml.size() == 1 || Rml[0].pv_score > Rml[1].pv_score + EasyMoveMargin))
+ // Init easyMove at first iteration or drop it if differs from the best move
+ if (depth == 1 && (Rml.size() == 1 || Rml[0].score > Rml[1].score + EasyMoveMargin))
easyMove = bestMove;
else if (bestMove != easyMove)
easyMove = MOVE_NONE;
// Check for some early stop condition
if (!StopRequest && Limits.useTimeManagement())
{
- // Stop search early when the last two iterations returned a mate score
- if ( depth >= 5
- && abs(bestValues[depth]) >= VALUE_MATE_IN_PLY_MAX
- && abs(bestValues[depth - 1]) >= VALUE_MATE_IN_PLY_MAX)
- StopRequest = true;
-
- // Stop search early if one move seems to be much better than the
- // others or if there is only a single legal move. Also in the latter
- // case we search up to some depth anyway to get a proper score.
+ // Easy move: Stop search early if one move seems to be much better
+ // than the others or if there is only a single legal move. Also in
+ // the latter case search to some depth anyway to get a proper score.
if ( depth >= 7
&& easyMove == bestMove
&& ( Rml.size() == 1
template <NodeType NT>
Value search(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth) {
- const bool PvNode = (NT == PV || NT == Root || NT == SplitPointPV);
- const bool SpNode = (NT == SplitPointPV || NT == SplitPointNonPV);
- const bool RootNode = (NT == Root);
+ const bool PvNode = (NT == PV || NT == Root || NT == SplitPointPV || NT == SplitPointRoot);
+ const bool SpNode = (NT == SplitPointPV || NT == SplitPointNonPV || NT == SplitPointRoot);
+ const bool RootNode = (NT == Root || NT == SplitPointRoot);
assert(alpha >= -VALUE_INFINITE && alpha <= VALUE_INFINITE);
assert(beta > alpha && beta <= VALUE_INFINITE);
Depth ext, newDepth;
ValueType vt;
Value bestValue, value, oldAlpha;
- Value refinedValue, nullValue, futilityBase, futilityValueScaled; // Non-PV specific
+ Value refinedValue, nullValue, futilityBase, futilityValue;
bool isPvMove, inCheck, singularExtensionNode, givesCheck, captureOrPromotion, dangerous;
int moveCount = 0, playedMoveCount = 0;
Thread& thread = Threads[pos.thread()];
excludedMove = ss->excludedMove;
posKey = excludedMove ? pos.get_exclusion_key() : pos.get_key();
tte = TT.probe(posKey);
- ttMove = tte ? tte->move() : MOVE_NONE;
+ ttMove = RootNode ? Rml[MultiPVIdx].pv[0] : tte ? tte->move() : MOVE_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.
- if (tte && (PvNode ? tte->depth() >= depth && tte->type() == VALUE_TYPE_EXACT
- : ok_to_use_TT(tte, depth, beta, ss->ply)))
+ // 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 && (PvNode ? tte->depth() >= depth && tte->type() == VALUE_TYPE_EXACT
+ : can_return_tt(tte, depth, beta, ss->ply)))
{
TT.refresh(tte);
- ss->bestMove = ttMove; // Can be MOVE_NONE
- return value_from_tt(tte->value(), ss->ply);
+ ss->bestMove = move = 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])
+ {
+ ss->killers[1] = ss->killers[0];
+ ss->killers[0] = move;
+ }
+ return value;
}
// Step 5. Evaluate the position statically and update parent's gain statistics
split_point_start: // At split points actual search starts from here
// Initialize a MovePicker object for the current position
- MovePickerExt<NT> mp(pos, ttMove, depth, H, ss, PvNode ? -VALUE_INFINITE : beta);
+ MovePickerExt<SpNode> mp(pos, ttMove, depth, H, ss, PvNode ? -VALUE_INFINITE : beta);
CheckInfo ci(pos);
ss->bestMove = MOVE_NONE;
futilityBase = ss->eval + ss->evalMargin;
&& (move = mp.get_next_move()) != MOVE_NONE
&& !thread.cutoff_occurred())
{
- assert(move_is_ok(move));
+ assert(is_ok(move));
if (move == excludedMove)
continue;
+ // At root obey the "searchmoves" option and skip moves not listed in Root
+ // Move List, as a consequence any illegal move is also skipped. In MultiPV
+ // mode we also skip PV moves which have been already searched.
+ if (RootNode && !Rml.find(move, MultiPVIdx))
+ continue;
+
// At PV and SpNode nodes we want all moves to be legal since the beginning
if ((PvNode || SpNode) && !pos.pl_move_is_legal(move, ci.pinned))
continue;
// Save the current node count before the move is searched
nodes = pos.nodes_searched();
- // If it's time to send nodes info, do it here where we have the
- // correct accumulated node counts searched by each thread.
- if (SendSearchedNodes)
- {
- SendSearchedNodes = false;
- cout << "info" << speed_to_uci(pos.nodes_searched()) << endl;
- }
-
// For long searches send current move info to GUI
- if (current_search_time() > 2000)
+ if (pos.thread() == 0 && current_search_time() > 2000)
cout << "info" << depth_to_uci(depth)
- << " currmove " << move << " currmovenumber " << moveCount << endl;
+ << " currmove " << move
+ << " currmovenumber " << moveCount + MultiPVIdx << endl;
}
// At Root and at first iteration do a PV search on all the moves to score root moves
- isPvMove = (PvNode && moveCount <= (!RootNode ? 1 : depth <= ONE_PLY ? MAX_MOVES : MultiPV));
+ isPvMove = (PvNode && moveCount <= (RootNode && depth <= ONE_PLY ? MAX_MOVES : 1));
givesCheck = pos.move_gives_check(move, ci);
- captureOrPromotion = pos.move_is_capture_or_promotion(move);
+ captureOrPromotion = pos.is_capture_or_promotion(move);
// Step 12. Decide the new search depth
ext = extension<PvNode>(pos, move, captureOrPromotion, givesCheck, &dangerous);
&& !inCheck
&& !dangerous
&& move != ttMove
- && !move_is_castle(move))
+ && !is_castle(move))
{
// Move count based pruning
if ( moveCount >= futility_move_count(depth)
// We illogically ignore reduction condition depth >= 3*ONE_PLY for predicted depth,
// but fixing this made program slightly weaker.
Depth predictedDepth = newDepth - reduction<PvNode>(depth, moveCount);
- futilityValueScaled = futilityBase + futility_margin(predictedDepth, moveCount)
- + H.gain(pos.piece_on(move_from(move)), move_to(move));
+ futilityValue = futilityBase + futility_margin(predictedDepth, moveCount)
+ + H.gain(pos.piece_on(move_from(move)), move_to(move));
- if (futilityValueScaled < beta)
+ if (futilityValue < beta)
{
if (SpNode)
{
lock_grab(&(sp->lock));
- if (futilityValueScaled > sp->bestValue)
- sp->bestValue = bestValue = futilityValueScaled;
+ if (futilityValue > sp->bestValue)
+ sp->bestValue = bestValue = futilityValue;
}
- else if (futilityValueScaled > bestValue)
- bestValue = futilityValueScaled;
+ else if (futilityValue > bestValue)
+ bestValue = futilityValue;
continue;
}
if ( depth > 3 * ONE_PLY
&& !captureOrPromotion
&& !dangerous
- && !move_is_castle(move)
+ && !is_castle(move)
&& ss->killers[0] != move
&& ss->killers[1] != move
&& (ss->reduction = reduction<PvNode>(depth, moveCount)) != DEPTH_ZERO)
alpha = sp->alpha;
}
- if (value > bestValue)
+ // Finished searching the move. If StopRequest is true, the search
+ // was aborted because the user interrupted the search or because we
+ // ran out of time. In this case, the return value of the search cannot
+ // be trusted, and we don't update the best move and/or PV.
+ if (RootNode && !StopRequest)
{
- bestValue = value;
- ss->bestMove = move;
-
- if ( !RootNode
- && PvNode
- && value > alpha
- && value < beta) // We want always alpha < beta
- alpha = value;
-
- if (SpNode && !thread.cutoff_occurred())
- {
- sp->bestValue = value;
- sp->ss->bestMove = move;
- sp->alpha = alpha;
- sp->is_betaCutoff = (value >= beta);
- }
- }
-
- if (RootNode)
- {
- // Finished searching the move. If StopRequest is true, the search
- // was aborted because the user interrupted the search or because we
- // ran out of time. In this case, the return value of the search cannot
- // be trusted, and we break out of the loop without updating the best
- // move and/or PV.
- if (StopRequest)
- break;
-
// Remember searched nodes counts for this move
- mp.current().nodes += pos.nodes_searched() - nodes;
+ RootMove* rm = Rml.find(move);
+ rm->nodes += pos.nodes_searched() - nodes;
// PV move or new best move ?
if (isPvMove || value > alpha)
{
// Update PV
- mp.current().pv_score = value;
- mp.current().extract_pv_from_tt(pos);
+ rm->score = value;
+ rm->extract_pv_from_tt(pos);
// We record how often the best move has been changed in each
// iteration. This information is used for time management: When
// the best move changes frequently, we allocate some more time.
if (!isPvMove && MultiPV == 1)
Rml.bestMoveChanges++;
-
- // It is critical that sorting is done with a stable algorithm
- // because all the values but the first are usually set to
- // -VALUE_INFINITE and we want to keep the same order for all
- // the moves but the new PV that goes to head.
- sort<RootMove>(Rml.begin(), Rml.begin() + moveCount);
-
- // Update alpha. In multi-pv we don't use aspiration window, so set
- // alpha equal to minimum score among the PV lines searched so far.
- if (MultiPV > 1)
- alpha = Rml[Min(moveCount, MultiPV) - 1].pv_score;
- else if (value > alpha)
- alpha = value;
}
else
// All other moves but the PV are set to the lowest value, this
// is not a problem when sorting becuase sort is stable and move
// position in the list is preserved, just the PV is pushed up.
- mp.current().pv_score = -VALUE_INFINITE;
+ rm->score = -VALUE_INFINITE;
} // RootNode
+ if (value > bestValue)
+ {
+ bestValue = value;
+ ss->bestMove = move;
+
+ if ( PvNode
+ && value > alpha
+ && value < beta) // We want always alpha < beta
+ alpha = value;
+
+ if (SpNode && !thread.cutoff_occurred())
+ {
+ sp->bestValue = value;
+ sp->ss->bestMove = move;
+ sp->alpha = alpha;
+ sp->is_betaCutoff = (value >= beta);
+ }
+ }
+
// Step 19. Check for split
- if ( !RootNode
- && !SpNode
+ if ( !SpNode
&& depth >= Threads.min_split_depth()
&& bestValue < beta
&& Threads.available_slave_exists(pos.thread())
&& !StopRequest
&& !thread.cutoff_occurred())
- Threads.split<FakeSplit>(pos, ss, &alpha, beta, &bestValue, depth,
- threatMove, moveCount, &mp, PvNode);
+ bestValue = Threads.split<FakeSplit>(pos, ss, alpha, beta, bestValue, depth,
+ threatMove, moveCount, &mp, NT);
}
// Step 20. Check for mate and stalemate
- // All legal moves have been searched and if there are
- // no legal moves, it must be mate or stalemate.
- // If one move was excluded return fail low score.
+ // All legal moves have been searched and if there are no legal moves, it
+ // must be mate or stalemate. Note that we can have a false positive in
+ // case of StopRequest or thread.cutoff_occurred() are set, but this is
+ // harmless because return value is discarded anyhow in the parent nodes.
+ // If we are in a singular extension search then return a fail low score.
if (!SpNode && !moveCount)
return excludedMove ? oldAlpha : inCheck ? value_mated_in(ss->ply) : VALUE_DRAW;
// Update killers and history only for non capture moves that fails high
if ( bestValue >= beta
- && !pos.move_is_capture_or_promotion(move))
+ && !pos.is_capture_or_promotion(move))
{
if (move != ss->killers[0])
{
bool inCheck, enoughMaterial, givesCheck, evasionPrunable;
const TTEntry* tte;
Depth ttDepth;
+ ValueType vt;
Value oldAlpha = alpha;
ss->bestMove = ss->currentMove = MOVE_NONE;
tte = TT.probe(pos.get_key());
ttMove = (tte ? tte->move() : MOVE_NONE);
- if (!PvNode && tte && ok_to_use_TT(tte, ttDepth, beta, ss->ply))
+ if (!PvNode && tte && can_return_tt(tte, ttDepth, beta, ss->ply))
{
ss->bestMove = ttMove; // Can be MOVE_NONE
return value_from_tt(tte->value(), ss->ply);
CheckInfo ci(pos);
// Loop through the moves until no moves remain or a beta cutoff occurs
- while ( alpha < beta
+ while ( bestValue < beta
&& (move = mp.get_next_move()) != MOVE_NONE)
{
- assert(move_is_ok(move));
+ assert(is_ok(move));
givesCheck = pos.move_gives_check(move, ci);
&& !givesCheck
&& move != ttMove
&& enoughMaterial
- && !move_is_promotion(move)
- && !pos.move_is_passed_pawn_push(move))
+ && !is_promotion(move)
+ && !pos.is_passed_pawn_push(move))
{
futilityValue = futilityBase
- + piece_value_endgame(pos.piece_on(move_to(move)))
- + (move_is_ep(move) ? PawnValueEndgame : VALUE_ZERO);
+ + PieceValueEndgame[pos.piece_on(move_to(move))]
+ + (is_enpassant(move) ? PawnValueEndgame : VALUE_ZERO);
- if (futilityValue < alpha)
+ if (futilityValue < beta)
{
if (futilityValue > bestValue)
bestValue = futilityValue;
+
continue;
}
evasionPrunable = !PvNode
&& inCheck
&& bestValue > VALUE_MATED_IN_PLY_MAX
- && !pos.move_is_capture(move)
+ && !pos.is_capture(move)
&& !pos.can_castle(pos.side_to_move());
// Don't search moves with negative SEE values
if ( !PvNode
&& (!inCheck || evasionPrunable)
&& move != ttMove
- && !move_is_promotion(move)
+ && !is_promotion(move)
&& pos.see_sign(move) < 0)
continue;
&& !inCheck
&& givesCheck
&& move != ttMove
- && !pos.move_is_capture_or_promotion(move)
+ && !pos.is_capture_or_promotion(move)
&& ss->eval + PawnValueMidgame / 4 < beta
&& !check_is_dangerous(pos, move, futilityBase, beta, &bestValue))
{
if (value > bestValue)
{
bestValue = value;
- if (value > alpha)
- {
+ ss->bestMove = move;
+
+ if ( PvNode
+ && value > alpha
+ && value < beta) // We want always alpha < beta
alpha = value;
- ss->bestMove = move;
- }
}
}
return value_mated_in(ss->ply);
// Update transposition table
- ValueType vt = (bestValue <= oldAlpha ? VALUE_TYPE_UPPER : bestValue >= beta ? VALUE_TYPE_LOWER : VALUE_TYPE_EXACT);
- TT.store(pos.get_key(), value_to_tt(bestValue, ss->ply), vt, ttDepth, ss->bestMove, ss->eval, evalMargin);
+ move = bestValue <= oldAlpha ? MOVE_NONE : ss->bestMove;
+ vt = bestValue <= oldAlpha ? VALUE_TYPE_UPPER
+ : bestValue >= beta ? VALUE_TYPE_LOWER : VALUE_TYPE_EXACT;
+
+ TT.store(pos.get_key(), value_to_tt(bestValue, ss->ply), vt, ttDepth, move, ss->eval, evalMargin);
assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
from = move_from(move);
to = move_to(move);
- them = opposite_color(pos.side_to_move());
+ them = flip(pos.side_to_move());
ksq = pos.king_square(them);
kingAtt = pos.attacks_from<KING>(ksq);
pc = pos.piece_on(from);
return true;
// Rule 2. Queen contact check is very dangerous
- if ( piece_type(pc) == QUEEN
+ if ( type_of(pc) == QUEEN
&& bit_is_set(kingAtt, to))
return true;
while (b)
{
victimSq = pop_1st_bit(&b);
- futilityValue = futilityBase + piece_value_endgame(pos.piece_on(victimSq));
+ futilityValue = futilityBase + PieceValueEndgame[pos.piece_on(victimSq)];
// Note that here we generate illegal "double move"!
if ( futilityValue >= beta
Piece p1, p2;
Square ksq;
- assert(m1 && move_is_ok(m1));
- assert(m2 && move_is_ok(m2));
+ assert(is_ok(m1));
+ assert(is_ok(m2));
// Case 1: The moving piece is the same in both moves
f2 = move_from(m2);
bool connected_threat(const Position& pos, Move m, Move threat) {
- assert(move_is_ok(m));
- assert(threat && move_is_ok(threat));
- assert(!pos.move_is_capture_or_promotion(m));
- assert(!pos.move_is_passed_pawn_push(m));
+ assert(is_ok(m));
+ assert(is_ok(threat));
+ assert(!pos.is_capture_or_promotion(m));
+ assert(!pos.is_passed_pawn_push(m));
Square mfrom, mto, tfrom, tto;
// Case 2: If the threatened piece has value less than or equal to the
// value of the threatening piece, don't prune moves which defend it.
- if ( pos.move_is_capture(threat)
- && ( piece_value_midgame(pos.piece_on(tfrom)) >= piece_value_midgame(pos.piece_on(tto))
- || piece_type(pos.piece_on(tfrom)) == KING)
+ if ( pos.is_capture(threat)
+ && ( PieceValueMidgame[pos.piece_on(tfrom)] >= PieceValueMidgame[pos.piece_on(tto)]
+ || type_of(pos.piece_on(tfrom)) == KING)
&& pos.move_attacks_square(m, tto))
return true;
}
- // ok_to_use_TT() returns true if a transposition table score
- // can be used at a given point in search.
+ // can_return_tt() returns true if a transposition table score
+ // can be used to cut-off at a given point in search.
- bool ok_to_use_TT(const TTEntry* tte, Depth depth, Value beta, int ply) {
+ bool can_return_tt(const TTEntry* tte, Depth depth, Value beta, int ply) {
Value v = value_from_tt(tte->value(), ply);
&& before != VALUE_NONE
&& after != VALUE_NONE
&& pos.captured_piece_type() == PIECE_TYPE_NONE
- && !move_is_special(m))
+ && !is_special(m))
H.update_gain(pos.piece_on(move_to(m)), move_to(m), -(before + after));
}
// mate <y> Mate in y moves, not plies. If the engine is getting mated
// use negative values for y.
- std::string score_to_uci(Value v, Value alpha, Value beta) {
+ string score_to_uci(Value v, Value alpha, Value beta) {
std::stringstream s;
// speed_to_uci() returns a string with time stats of current search suitable
// to be sent to UCI gui.
- std::string speed_to_uci(int64_t nodes) {
+ string speed_to_uci(int64_t nodes) {
std::stringstream s;
int t = current_search_time();
// pv_to_uci() returns a string with information on the current PV line
// formatted according to UCI specification.
- std::string pv_to_uci(Move pv[], int pvNum) {
+ string pv_to_uci(const Move pv[], int pvNum, bool chess960) {
std::stringstream s;
- s << " multipv " << pvNum << " pv ";
+ s << " multipv " << pvNum << " pv " << set960(chess960);
for ( ; *pv != MOVE_NONE; pv++)
s << *pv << " ";
// depth_to_uci() returns a string with information on the current depth and
// seldepth formatted according to UCI specification.
- std::string depth_to_uci(Depth depth) {
+ string depth_to_uci(Depth depth) {
std::stringstream s;
return s.str();
}
+ string time_to_string(int millisecs) {
+
+ const int MSecMinute = 1000 * 60;
+ const int MSecHour = 1000 * 60 * 60;
+
+ int hours = millisecs / MSecHour;
+ int minutes = (millisecs % MSecHour) / MSecMinute;
+ int seconds = ((millisecs % MSecHour) % MSecMinute) / 1000;
+
+ std::stringstream s;
+
+ if (hours)
+ s << hours << ':';
+
+ s << std::setfill('0') << std::setw(2) << minutes << ':' << std::setw(2) << seconds;
+ return s.str();
+ }
+
+ string score_to_string(Value v) {
+
+ std::stringstream s;
+
+ if (v >= VALUE_MATE_IN_PLY_MAX)
+ s << "#" << (VALUE_MATE - v + 1) / 2;
+ else if (v <= VALUE_MATED_IN_PLY_MAX)
+ s << "-#" << (VALUE_MATE + v) / 2;
+ else
+ s << std::setprecision(2) << std::fixed << std::showpos << float(v) / PawnValueMidgame;
+
+ return s.str();
+ }
+
+ // pretty_pv() creates a human-readable string from a position and a PV.
+ // It is used to write search information to the log file (which is created
+ // when the UCI parameter "Use Search Log" is "true").
+
+ string pretty_pv(Position& pos, int depth, Value value, int time, Move pv[]) {
+
+ const int64_t K = 1000;
+ const int64_t M = 1000000;
+ const int startColumn = 28;
+ const size_t maxLength = 80 - startColumn;
+
+ StateInfo state[PLY_MAX_PLUS_2], *st = state;
+ Move* m = pv;
+ string san;
+ std::stringstream s;
+ size_t length = 0;
+
+ // First print depth, score, time and searched nodes...
+ s << set960(pos.is_chess960())
+ << std::setw(2) << depth
+ << std::setw(8) << score_to_string(value)
+ << std::setw(8) << time_to_string(time);
+
+ if (pos.nodes_searched() < M)
+ s << std::setw(8) << pos.nodes_searched() / 1 << " ";
+ else if (pos.nodes_searched() < K * M)
+ s << std::setw(7) << pos.nodes_searched() / K << "K ";
+ else
+ s << std::setw(7) << pos.nodes_searched() / M << "M ";
+
+ // ...then print the full PV line in short algebraic notation
+ while (*m != MOVE_NONE)
+ {
+ san = move_to_san(pos, *m);
+ length += san.length() + 1;
+
+ if (length > maxLength)
+ {
+ length = san.length() + 1;
+ s << "\n" + string(startColumn, ' ');
+ }
+ s << san << ' ';
+
+ pos.do_move(*m++, *st++);
+ }
+
+ // Restore original position before to leave
+ while (m != pv) pos.undo_move(*--m);
+
+ return s.str();
+ }
// poll() performs two different functions: It polls for user input, and it
// looks at the time consumed so far and decides if it's time to abort the
if (input_available())
{
// We are line oriented, don't read single chars
- std::string command;
+ string command;
if (!std::getline(std::cin, command) || command == "quit")
{
dbg_print_mean();
dbg_print_hit_rate();
-
- // Send info on searched nodes as soon as we return to root
- SendSearchedNodes = true;
}
// Should we stop the search?
void wait_for_stop_or_ponderhit() {
- std::string command;
+ string command;
// Wait for a command from stdin
while ( std::getline(std::cin, command)
static RKISS rk;
- // Rml list is already sorted by pv_score in descending order
+ // Rml list is already sorted by score in descending order
int s;
int max_s = -VALUE_INFINITE;
int size = Min(MultiPV, (int)Rml.size());
- int max = Rml[0].pv_score;
- int var = Min(max - Rml[size - 1].pv_score, PawnValueMidgame);
+ int max = Rml[0].score;
+ int var = Min(max - Rml[size - 1].score, PawnValueMidgame);
int wk = 120 - 2 * SkillLevel;
// PRNG sequence should be non deterministic
// then we choose the move with the resulting highest score.
for (int i = 0; i < size; i++)
{
- s = Rml[i].pv_score;
+ s = Rml[i].score;
// Don't allow crazy blunders even at very low skills
- if (i > 0 && Rml[i-1].pv_score > s + EasyMoveMargin)
+ if (i > 0 && Rml[i-1].score > s + EasyMoveMargin)
break;
// This is our magical formula
/// RootMove and RootMoveList method's definitions
- RootMove::RootMove() {
-
- nodes = 0;
- pv_score = non_pv_score = -VALUE_INFINITE;
- pv[0] = MOVE_NONE;
- }
-
- RootMove& RootMove::operator=(const RootMove& rm) {
-
- const Move* src = rm.pv;
- Move* dst = pv;
-
- // Avoid a costly full rm.pv[] copy
- do *dst++ = *src; while (*src++ != MOVE_NONE);
-
- nodes = rm.nodes;
- pv_score = rm.pv_score;
- non_pv_score = rm.non_pv_score;
- return *this;
- }
-
void RootMoveList::init(Position& pos, Move searchMoves[]) {
Move* sm;
continue;
RootMove rm;
- rm.pv[0] = ml.move();
- rm.pv[1] = MOVE_NONE;
- rm.pv_score = -VALUE_INFINITE;
+ rm.pv.push_back(ml.move());
+ rm.pv.push_back(MOVE_NONE);
+ rm.score = rm.prevScore = -VALUE_INFINITE;
+ rm.nodes = 0;
push_back(rm);
}
}
+ RootMove* RootMoveList::find(const Move& m, int startIndex) {
+
+ for (size_t i = startIndex; i < size(); i++)
+ if ((*this)[i].pv[0] == m)
+ return &(*this)[i];
+
+ return NULL;
+ }
+
// extract_pv_from_tt() builds a PV by adding moves from the transposition table.
// We consider also failing high nodes and not only VALUE_TYPE_EXACT nodes. This
// allow to always have a ponder move even when we fail high at root and also a
StateInfo state[PLY_MAX_PLUS_2], *st = state;
TTEntry* tte;
int ply = 1;
+ Move m = pv[0];
- assert(pv[0] != MOVE_NONE && pos.move_is_pl(pv[0]));
+ assert(m != MOVE_NONE && pos.is_pseudo_legal(m));
- pos.do_move(pv[0], *st++);
+ pv.clear();
+ pv.push_back(m);
+ pos.do_move(m, *st++);
while ( (tte = TT.probe(pos.get_key())) != NULL
&& tte->move() != MOVE_NONE
- && pos.move_is_pl(tte->move())
+ && pos.is_pseudo_legal(tte->move())
&& pos.pl_move_is_legal(tte->move(), pos.pinned_pieces())
&& ply < PLY_MAX
&& (!pos.is_draw<false>() || ply < 2))
{
- pv[ply] = tte->move();
- pos.do_move(pv[ply++], *st++);
+ pv.push_back(tte->move());
+ pos.do_move(tte->move(), *st++);
+ ply++;
}
- pv[ply] = MOVE_NONE;
+ pv.push_back(MOVE_NONE);
do pos.undo_move(pv[--ply]); while (ply);
}
Value v, m = VALUE_NONE;
int ply = 0;
- assert(pv[0] != MOVE_NONE && pos.move_is_pl(pv[0]));
+ assert(pv[0] != MOVE_NONE && pos.is_pseudo_legal(pv[0]));
do {
k = pos.get_key();
do pos.undo_move(pv[--ply]); while (ply);
}
+} // namespace
- // Specializations for MovePickerExt in case of Root node
- MovePickerExt<Root>::MovePickerExt(const Position& p, Move ttm, Depth d,
- const History& h, SearchStack* ss, Value b)
- : MovePicker(p, ttm, d, h, ss, b), cur(-1) {
- Move move;
- Value score = VALUE_ZERO;
-
- // Score root moves using standard ordering used in main search, the moves
- // are scored according to the order in which they are returned by MovePicker.
- // This is the second order score that is used to compare the moves when
- // the first orders pv_score of both moves are equal.
- while ((move = MovePicker::get_next_move()) != MOVE_NONE)
- for (RootMoveList::iterator rm = Rml.begin(); rm != Rml.end(); ++rm)
- if (rm->pv[0] == move)
- {
- rm->non_pv_score = score--;
- break;
- }
- sort<RootMove>(Rml.begin(), Rml.end());
- }
+// Little helper used by idle_loop() to check that all the slave threads of a
+// split point have finished searching.
-} // namespace
+static bool all_slaves_finished(SplitPoint* sp) {
+ for (int i = 0; i < Threads.size(); i++)
+ if (sp->is_slave[i])
+ return false;
-// ThreadsManager::idle_loop() is where the threads are parked when they have no work
-// to do. The parameter 'sp', if non-NULL, is a pointer to an active SplitPoint
-// object for which the current thread is the master.
+ return true;
+}
-void ThreadsManager::idle_loop(int threadID, SplitPoint* sp) {
- assert(threadID >= 0 && threadID < MAX_THREADS);
+// Thread::idle_loop() is where the thread is parked when it has no work to do.
+// The parameter 'sp', if non-NULL, is a pointer to an active SplitPoint object
+// for which the thread is the master.
- int i;
- bool allFinished;
+void Thread::idle_loop(SplitPoint* sp) {
while (true)
{
- // Slave threads can exit as soon as AllThreadsShouldExit raises,
- // master should exit as last one.
- if (allThreadsShouldExit)
- {
- assert(!sp);
- threads[threadID].state = Thread::TERMINATED;
- return;
- }
-
- // If we are not thinking, wait for a condition to be signaled
+ // If we are not searching, wait for a condition to be signaled
// instead of wasting CPU time polling for work.
- while ( threadID >= activeThreads
- || threads[threadID].state == Thread::INITIALIZING
- || (useSleepingThreads && threads[threadID].state == Thread::AVAILABLE))
+ while ( do_sleep
+ || do_terminate
+ || (Threads.use_sleeping_threads() && !is_searching))
{
- assert(!sp || useSleepingThreads);
- assert(threadID != 0 || useSleepingThreads);
+ assert((!sp && threadID) || Threads.use_sleeping_threads());
- if (threads[threadID].state == Thread::INITIALIZING)
- threads[threadID].state = Thread::AVAILABLE;
+ // Slave thread should exit as soon as do_terminate flag raises
+ if (do_terminate)
+ {
+ assert(!sp);
+ return;
+ }
// Grab the lock to avoid races with Thread::wake_up()
- lock_grab(&threads[threadID].sleepLock);
-
- // If we are master and all slaves have finished do not go to sleep
- for (i = 0; sp && i < activeThreads && !sp->is_slave[i]; i++) {}
- allFinished = (i == activeThreads);
+ lock_grab(&sleepLock);
- if (allFinished || allThreadsShouldExit)
+ // If we are master and all slaves have finished don't go to sleep
+ if (sp && all_slaves_finished(sp))
{
- lock_release(&threads[threadID].sleepLock);
+ lock_release(&sleepLock);
break;
}
- // Do sleep here after retesting sleep conditions
- if (threadID >= activeThreads || threads[threadID].state == Thread::AVAILABLE)
- cond_wait(&threads[threadID].sleepCond, &threads[threadID].sleepLock);
+ // Do sleep after retesting sleep conditions under lock protection, in
+ // particular we need to avoid a deadlock in case a master thread has,
+ // in the meanwhile, allocated us and sent the wake_up() call before we
+ // had the chance to grab the lock.
+ if (do_sleep || !is_searching)
+ cond_wait(&sleepCond, &sleepLock);
- lock_release(&threads[threadID].sleepLock);
+ lock_release(&sleepLock);
}
// If this thread has been assigned work, launch a search
- if (threads[threadID].state == Thread::WORKISWAITING)
+ if (is_searching)
{
- assert(!allThreadsShouldExit);
-
- threads[threadID].state = Thread::SEARCHING;
+ assert(!do_terminate);
// Copy split point position and search stack and call search()
- // with SplitPoint template parameter set to true.
SearchStack ss[PLY_MAX_PLUS_2];
- SplitPoint* tsp = threads[threadID].splitPoint;
+ SplitPoint* tsp = splitPoint;
Position pos(*tsp->pos, threadID);
memcpy(ss, tsp->ss - 1, 4 * sizeof(SearchStack));
(ss+1)->sp = tsp;
- if (tsp->pvNode)
+ if (tsp->nodeType == Root)
+ search<SplitPointRoot>(pos, ss+1, tsp->alpha, tsp->beta, tsp->depth);
+ else if (tsp->nodeType == PV)
search<SplitPointPV>(pos, ss+1, tsp->alpha, tsp->beta, tsp->depth);
- else
+ else if (tsp->nodeType == NonPV)
search<SplitPointNonPV>(pos, ss+1, tsp->alpha, tsp->beta, tsp->depth);
+ else
+ assert(false);
- assert(threads[threadID].state == Thread::SEARCHING);
+ assert(is_searching);
- threads[threadID].state = Thread::AVAILABLE;
+ is_searching = false;
// 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 ( useSleepingThreads
+ if ( Threads.use_sleeping_threads()
&& threadID != tsp->master
- && threads[tsp->master].state == Thread::AVAILABLE)
- threads[tsp->master].wake_up();
+ && !Threads[tsp->master].is_searching)
+ Threads[tsp->master].wake_up();
}
// If this thread is the master of a split point and all slaves have
// finished their work at this split point, return from the idle loop.
- for (i = 0; sp && i < activeThreads && !sp->is_slave[i]; i++) {}
- allFinished = (i == activeThreads);
-
- if (allFinished)
+ if (sp && all_slaves_finished(sp))
{
- // Because sp->slaves[] is reset under lock protection,
+ // Because sp->is_slave[] is reset under lock protection,
// be sure sp->lock has been released before to return.
lock_grab(&(sp->lock));
lock_release(&(sp->lock));
-
- // In helpful master concept a master can help only a sub-tree, and
- // because here is all finished is not possible master is booked.
- assert(threads[threadID].state == Thread::AVAILABLE);
-
- threads[threadID].state = Thread::SEARCHING;
return;
}
}
projects / stockfish / blobdiff