typedef std::vector<RootMove> Base;
RootMoveList(Position& pos, Move searchMoves[]);
- void set_non_pv_scores(const Position& pos);
+ void set_non_pv_scores(const Position& pos, Move ttm, SearchStack* ss);
void sort() { insertion_sort<RootMove, Base::iterator>(begin(), end()); }
void sort_multipv(int n) { insertion_sort<RootMove, Base::iterator>(begin(), begin() + n); }
// operator<<() that will use it to properly format castling moves.
enum set960 {};
- std::ostream& operator<< (std::ostream& os, const set960& m) {
+ std::ostream& operator<< (std::ostream& os, const set960& f) {
- os.iword(0) = int(m);
+ os.iword(0) = int(f);
return os;
}
+ // Overload operator << for moves to make it easier to print moves in
+ // coordinate notation compatible with UCI protocol.
+
+ std::ostream& operator<<(std::ostream& os, Move m);
+
+
/// Adjustments
// Step 6. Razoring
// Time managment variables
int SearchStartTime, MaxNodes, MaxDepth, ExactMaxTime;
- bool UseTimeManagement, InfiniteSearch, PonderSearch, StopOnPonderhit;
- bool FirstRootMove, AbortSearch, Quit, AspirationFailLow;
+ bool UseTimeManagement, InfiniteSearch, Pondering, StopOnPonderhit;
+ bool FirstRootMove, StopRequest, QuitRequest, AspirationFailLow;
TimeManager TimeMgr;
// Log file
// 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;
/// Local functions
- Value id_loop(Position& pos, Move searchMoves[]);
+ Move id_loop(Position& pos, Move searchMoves[], Move* ponderMove);
Value root_search(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth, RootMoveList& rml);
template <NodeType PvNode, bool SpNode>
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 update_killers(Move m, SearchStack* ss);
+ void update_killers(Move m, Move killers[]);
void update_gains(const Position& pos, Move move, Value before, Value after);
int current_search_time();
std::string value_to_uci(Value v);
int nps(const Position& pos);
void poll(const Position& pos);
- void ponderhit();
void wait_for_stop_or_ponderhit();
void init_ss_array(SearchStack* ss, int size);
/// perft() is our utility to verify move generation is bug free. All the legal
/// moves up to given depth are generated and counted and the sum returned.
-int perft(Position& pos, Depth depth)
+int64_t perft(Position& pos, Depth depth)
{
MoveStack mlist[MOVES_MAX];
StateInfo st;
Move m;
- int sum = 0;
+ int64_t sum = 0;
// Generate all legal moves
MoveStack* last = generate_moves(pos, mlist);
int movesToGo, int maxDepth, int maxNodes, int maxTime, Move searchMoves[]) {
// Initialize global search variables
- StopOnPonderhit = AbortSearch = Quit = AspirationFailLow = false;
+ StopOnPonderhit = StopRequest = QuitRequest = AspirationFailLow = SendSearchedNodes = false;
NodesSincePoll = 0;
SearchStartTime = get_system_time();
ExactMaxTime = maxTime;
MaxDepth = maxDepth;
MaxNodes = maxNodes;
InfiniteSearch = infinite;
- PonderSearch = ponder;
+ Pondering = ponder;
UseTimeManagement = !ExactMaxTime && !MaxDepth && !MaxNodes && !InfiniteSearch;
// Look for a book move, only during games, not tests
Move bookMove = OpeningBook.get_move(pos, Options["Best Book Move"].value<bool>());
if (bookMove != MOVE_NONE)
{
- if (PonderSearch)
+ if (Pondering)
wait_for_stop_or_ponderhit();
cout << "bestmove " << bookMove << endl;
- return true;
+ return !QuitRequest;
}
}
MultiPV = Options["MultiPV"].value<int>();
UseLogFile = Options["Use Search Log"].value<bool>();
- if (UseLogFile)
- LogFile.open(Options["Search Log Filename"].value<std::string>().c_str(), std::ios::out | std::ios::app);
-
- read_weights(pos.side_to_move());
+ read_evaluation_uci_options(pos.side_to_move());
// Set the number of active threads
ThreadsMgr.read_uci_options();
// Write search information to log file
if (UseLogFile)
- LogFile << "Searching: " << pos.to_fen() << endl
- << "infinite: " << infinite
- << " ponder: " << ponder
- << " time: " << myTime
+ {
+ std::string name = Options["Search Log Filename"].value<std::string>();
+ LogFile.open(name.c_str(), std::ios::out | std::ios::app);
+
+ LogFile << "Searching: " << pos.to_fen()
+ << "\ninfinite: " << infinite
+ << " ponder: " << ponder
+ << " time: " << myTime
<< " increment: " << myIncrement
<< " moves to go: " << movesToGo << endl;
+ }
// We're ready to start thinking. Call the iterative deepening loop function
- id_loop(pos, searchMoves);
+ Move ponderMove = MOVE_NONE;
+ Move bestMove = id_loop(pos, searchMoves, &ponderMove);
+
+ // Print final search statistics
+ cout << "info nodes " << pos.nodes_searched()
+ << " nps " << nps(pos)
+ << " time " << current_search_time() << endl;
if (UseLogFile)
+ {
+ LogFile << "\nNodes: " << pos.nodes_searched()
+ << "\nNodes/second: " << nps(pos)
+ << "\nBest move: " << move_to_san(pos, bestMove);
+
+ StateInfo st;
+ pos.do_move(bestMove, st);
+ LogFile << "\nPonder move: "
+ << move_to_san(pos, ponderMove) // Works also with MOVE_NONE
+ << endl;
+
+ // Return from think() with unchanged position
+ pos.undo_move(bestMove);
+
LogFile.close();
+ }
// This makes all the threads to go to sleep
ThreadsMgr.set_active_threads(1);
- return !Quit;
+ // If we are pondering or in infinite search, we shouldn't print the
+ // best move before we are told to do so.
+ if (!StopRequest && (Pondering || InfiniteSearch))
+ wait_for_stop_or_ponderhit();
+
+ // Could be both MOVE_NONE when searching on a stalemate position
+ cout << "bestmove " << bestMove << " ponder " << ponderMove << endl;
+
+ return !QuitRequest;
}
// been consumed, the user stops the search, or the maximum search depth is
// reached.
- Value id_loop(Position& pos, Move searchMoves[]) {
+ Move id_loop(Position& pos, Move searchMoves[], Move* ponderMove) {
SearchStack ss[PLY_MAX_PLUS_2];
Depth depth;
// Handle special case of searching on a mate/stale position
if (rml.size() == 0)
{
- if (PonderSearch)
- wait_for_stop_or_ponderhit();
+ Value s = (pos.is_check() ? -VALUE_MATE : VALUE_DRAW);
+
+ cout << "info depth " << 1
+ << " score " << value_to_uci(s) << endl;
- return pos.is_check() ? -VALUE_MATE : VALUE_DRAW;
+ return MOVE_NONE;
}
// Initialize
// Search to the current depth, rml is updated and sorted
value = root_search(pos, ss, alpha, beta, depth, rml);
- if (AbortSearch)
+ if (StopRequest)
break; // Value cannot be trusted. Break out immediately!
//Save info about search result
if (stopSearch)
{
- if (PonderSearch)
+ if (Pondering)
StopOnPonderhit = true;
else
break;
break;
}
- // If we are pondering or in infinite search, we shouldn't print the
- // best move before we are told to do so.
- if (!AbortSearch && (PonderSearch || InfiniteSearch))
- wait_for_stop_or_ponderhit();
- else
- // Print final search statistics
- cout << "info nodes " << pos.nodes_searched()
- << " nps " << nps(pos)
- << " time " << current_search_time() << endl;
-
- // Print the best move and the ponder move to the standard output
- cout << "bestmove " << rml[0].pv[0];
-
- if (rml[0].pv[1] != MOVE_NONE)
- cout << " ponder " << rml[0].pv[1];
-
- cout << endl;
-
- if (UseLogFile)
- {
- if (dbg_show_mean)
- dbg_print_mean(LogFile);
-
- if (dbg_show_hit_rate)
- dbg_print_hit_rate(LogFile);
-
- LogFile << "\nNodes: " << pos.nodes_searched()
- << "\nNodes/second: " << nps(pos)
- << "\nBest move: " << move_to_san(pos, rml[0].pv[0]);
-
- StateInfo st;
- pos.do_move(rml[0].pv[0], st);
- LogFile << "\nPonder move: "
- << move_to_san(pos, rml[0].pv[1]) // Works also with MOVE_NONE
- << endl;
- }
- return rml[0].pv_score;
+ *ponderMove = rml[0].pv[1];
+ return rml[0].pv[0];
}
Value root_search(Position& pos, SearchStack* ss, Value alpha,
Value beta, Depth depth, RootMoveList& rml) {
StateInfo st;
+ Move movesSearched[MOVES_MAX];
CheckInfo ci(pos);
int64_t nodes;
Move move;
Depth ext, newDepth;
Value value, oldAlpha;
- bool isCheck, moveIsCheck, captureOrPromotion, dangerous;
- int researchCountFH, researchCountFL;
+ RootMoveList::iterator rm;
+ bool isCheck, moveIsCheck, captureOrPromotion, dangerous, isPvMove;
+ int moveCount, researchCountFH, researchCountFL;
researchCountFH = researchCountFL = 0;
oldAlpha = alpha;
while (1)
{
// Sort the moves before to (re)search
- rml.set_non_pv_scores(pos);
+ rml.set_non_pv_scores(pos, rml[0].pv[0], ss);
rml.sort();
+ moveCount = 0;
// Step 10. Loop through all moves in the root move list
- for (int i = 0; i < (int)rml.size() && !AbortSearch; i++)
+ for (rm = rml.begin(); rm != rml.end() && !StopRequest; ++rm)
{
// This is used by time management
- FirstRootMove = (i == 0);
+ FirstRootMove = (rm == rml.begin());
// 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 nodes " << nodes
+ << " nps " << nps(pos)
+ << " time " << current_search_time() << endl;
+ }
+
// Pick the next root move, and print the move and the move number to
// the standard output.
- move = ss->currentMove = rml[i].pv[0];
+ move = ss->currentMove = rm->pv[0];
+ movesSearched[moveCount++] = move;
+ isPvMove = (moveCount <= MultiPV);
if (current_search_time() >= 1000)
cout << "info currmove " << move
- << " currmovenumber " << i + 1 << endl;
+ << " currmovenumber " << moveCount << endl;
moveIsCheck = pos.move_is_check(move);
captureOrPromotion = pos.move_is_capture_or_promotion(move);
pos.do_move(move, st, ci, moveIsCheck);
// Step extra. pv search
- // We do pv search for first moves (i < MultiPV)
- // and for fail high research (value > alpha)
- if (i < MultiPV || value > alpha)
+ // We do pv search for PV moves and when failing high
+ if (isPvMove || value > alpha)
{
// Aspiration window is disabled in multi-pv case
if (MultiPV > 1)
&& !captureOrPromotion
&& !move_is_castle(move))
{
- ss->reduction = reduction<PV>(depth, i - MultiPV + 2);
+ ss->reduction = reduction<PV>(depth, moveCount - MultiPV + 1);
if (ss->reduction)
{
assert(newDepth-ss->reduction >= ONE_PLY);
pos.undo_move(move);
// Can we exit fail high loop ?
- if (AbortSearch || value < beta)
+ if (StopRequest || value < beta)
break;
// We are failing high and going to do a research. It's important to update
// the score before research in case we run out of time while researching.
ss->bestMove = move;
- rml[i].pv_score = value;
- rml[i].extract_pv_from_tt(pos);
+ rm->pv_score = value;
+ rm->extract_pv_from_tt(pos);
+
+ // Update killers and history only for non capture moves that fails high
+ if (!pos.move_is_capture_or_promotion(move))
+ {
+ update_history(pos, move, depth, movesSearched, moveCount);
+ update_killers(move, ss->killers);
+ }
// Inform GUI that PV has changed
- cout << rml[i].pv_info_to_uci(pos, alpha, beta) << endl;
+ cout << rm->pv_info_to_uci(pos, alpha, beta) << endl;
// Prepare for a research after a fail high, each time with a wider window
beta = Min(beta + AspirationDelta * (1 << researchCountFH), VALUE_INFINITE);
// 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 (AbortSearch)
+ if (StopRequest)
break;
// Remember searched nodes counts for this move
- rml[i].nodes += pos.nodes_searched() - nodes;
+ rm->nodes += pos.nodes_searched() - nodes;
assert(value >= -VALUE_INFINITE && value <= VALUE_INFINITE);
assert(value < beta);
// Step 17. Check for new best move
- if (value <= alpha && i >= MultiPV)
- rml[i].pv_score = -VALUE_INFINITE;
+ if (!isPvMove && value <= alpha)
+ rm->pv_score = -VALUE_INFINITE;
else
{
// PV move or new best move!
// Update PV
ss->bestMove = move;
- rml[i].pv_score = value;
- rml[i].extract_pv_from_tt(pos);
+ rm->pv_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 managment: When
// the best move changes frequently, we allocate some more time.
- if (MultiPV == 1 && i > 0)
+ if (!isPvMove && MultiPV == 1)
BestMoveChangesByIteration[Iteration]++;
// Inform GUI that PV has changed, in case of multi-pv UCI protocol
// requires we send all the PV lines properly sorted.
- rml.sort_multipv(i);
+ rml.sort_multipv(moveCount);
for (int j = 0; j < Min(MultiPV, (int)rml.size()); j++)
cout << rml[j].pv_info_to_uci(pos, alpha, beta, j) << endl;
alpha = value;
}
else // Set alpha equal to minimum score among the PV lines
- alpha = rml[Min(i, MultiPV - 1)].pv_score;
+ alpha = rml[Min(moveCount, MultiPV) - 1].pv_score; // FIXME why moveCount?
} // PV move or new best move
} // Root moves loop
// Can we exit fail low loop ?
- if (AbortSearch || !AspirationFailLow)
+ if (StopRequest || !AspirationFailLow)
break;
// Prepare for a research after a fail low, each time with a wider window
// Write PV lines to transposition table, in case the relevant entries
// have been overwritten during the search.
- for (int i = 0; i < MultiPV; i++)
+ for (int i = 0; i < Min(MultiPV, (int)rml.size()); i++)
rml[i].insert_pv_in_tt(pos);
return alpha;
}
// Step 2. Check for aborted search and immediate draw
- if ( AbortSearch
+ if ( StopRequest
|| ThreadsMgr.cutoff_at_splitpoint(threadID)
|| pos.is_draw()
|| ply >= PLY_MAX - 1)
&& ThreadsMgr.active_threads() > 1
&& bestValue < beta
&& ThreadsMgr.available_thread_exists(threadID)
- && !AbortSearch
+ && !StopRequest
&& !ThreadsMgr.cutoff_at_splitpoint(threadID)
&& Iteration <= 99)
ThreadsMgr.split<FakeSplit>(pos, ss, ply, &alpha, beta, &bestValue, depth,
// Step 20. Update tables
// If the search is not aborted, update the transposition table,
// history counters, and killer moves.
- if (!SpNode && !AbortSearch && !ThreadsMgr.cutoff_at_splitpoint(threadID))
+ if (!SpNode && !StopRequest && !ThreadsMgr.cutoff_at_splitpoint(threadID))
{
move = bestValue <= oldAlpha ? MOVE_NONE : ss->bestMove;
vt = bestValue <= oldAlpha ? VALUE_TYPE_UPPER
&& !pos.move_is_capture_or_promotion(move))
{
update_history(pos, move, depth, movesSearched, moveCount);
- update_killers(move, ss);
+ update_killers(move, ss->killers);
}
}
// update_killers() add a good move that produced a beta-cutoff
// among the killer moves of that ply.
- void update_killers(Move m, SearchStack* ss) {
+ void update_killers(Move m, Move killers[]) {
- if (m == ss->killers[0])
+ if (m == killers[0])
return;
- ss->killers[1] = ss->killers[0];
- ss->killers[0] = m;
+ killers[1] = killers[0];
+ killers[0] = m;
}
}
- // current_search_time() returns the number of milliseconds which have passed
- // since the beginning of the current search.
+ // init_ss_array() does a fast reset of the first entries of a SearchStack
+ // array and of all the excludedMove and skipNullMove entries.
- int current_search_time() {
+ void init_ss_array(SearchStack* ss, int size) {
- return get_system_time() - SearchStartTime;
+ for (int i = 0; i < size; i++, ss++)
+ {
+ ss->excludedMove = MOVE_NONE;
+ ss->skipNullMove = false;
+ ss->reduction = DEPTH_ZERO;
+ ss->sp = NULL;
+
+ if (i < 3)
+ ss->killers[0] = ss->killers[1] = ss->mateKiller = MOVE_NONE;
+ }
}
return s.str();
}
- // nps() computes the current nodes/second count.
+
+ // current_search_time() returns the number of milliseconds which have passed
+ // since the beginning of the current search.
+
+ int current_search_time() {
+
+ return get_system_time() - SearchStartTime;
+ }
+
+
+ // nps() computes the current nodes/second count
int nps(const Position& pos) {
if (command == "quit")
{
- AbortSearch = true;
- PonderSearch = false;
- Quit = true;
+ // Quit the program as soon as possible
+ Pondering = false;
+ QuitRequest = StopRequest = true;
return;
}
else if (command == "stop")
{
- AbortSearch = true;
- PonderSearch = false;
+ // Stop calculating as soon as possible, but still send the "bestmove"
+ // and possibly the "ponder" token when finishing the search.
+ Pondering = false;
+ StopRequest = true;
}
else if (command == "ponderhit")
- ponderhit();
+ {
+ // The opponent has played the expected move. GUI sends "ponderhit" if
+ // we were told to ponder on the same move the opponent has played. We
+ // should continue searching but switching from pondering to normal search.
+ Pondering = false;
+
+ if (StopOnPonderhit)
+ StopRequest = true;
+ }
}
// Print search information
if (dbg_show_hit_rate)
dbg_print_hit_rate();
- cout << "info nodes " << pos.nodes_searched() << " nps " << nps(pos)
- << " time " << t << endl;
+ // Send info on searched nodes as soon as we return to root
+ SendSearchedNodes = true;
}
// Should we stop the search?
- if (PonderSearch)
+ if (Pondering)
return;
bool stillAtFirstMove = FirstRootMove
bool noMoreTime = t > TimeMgr.maximum_time()
|| stillAtFirstMove;
- if ( (Iteration >= 3 && UseTimeManagement && noMoreTime)
+ if ( (UseTimeManagement && noMoreTime)
|| (ExactMaxTime && t >= ExactMaxTime)
- || (Iteration >= 3 && MaxNodes && pos.nodes_searched() >= MaxNodes))
- AbortSearch = true;
- }
-
-
- // ponderhit() is called when the program is pondering (i.e. thinking while
- // it's the opponent's turn to move) in order to let the engine know that
- // it correctly predicted the opponent's move.
-
- void ponderhit() {
-
- int t = current_search_time();
- PonderSearch = false;
-
- bool stillAtFirstMove = FirstRootMove
- && !AspirationFailLow
- && t > TimeMgr.available_time();
-
- bool noMoreTime = t > TimeMgr.maximum_time()
- || stillAtFirstMove;
-
- if (Iteration >= 3 && UseTimeManagement && (noMoreTime || StopOnPonderhit))
- AbortSearch = true;
- }
-
-
- // init_ss_array() does a fast reset of the first entries of a SearchStack
- // array and of all the excludedMove and skipNullMove entries.
-
- void init_ss_array(SearchStack* ss, int size) {
-
- for (int i = 0; i < size; i++, ss++)
- {
- ss->excludedMove = MOVE_NONE;
- ss->skipNullMove = false;
- ss->reduction = DEPTH_ZERO;
- ss->sp = NULL;
-
- if (i < 3)
- ss->killers[0] = ss->killers[1] = ss->mateKiller = MOVE_NONE;
- }
+ || (MaxNodes && pos.nodes_searched() >= MaxNodes)) // FIXME
+ StopRequest = true;
}
// the UCI protocol: When pondering, the engine is not allowed to give a
// "bestmove" before the GUI sends it a "stop" or "ponderhit" command.
// We simply wait here until one of these commands is sent, and return,
- // after which the bestmove and pondermove will be printed (in id_loop()).
+ // after which the bestmove and pondermove will be printed.
void wait_for_stop_or_ponderhit() {
while (true)
{
+ // Wait for a command from stdin
if (!std::getline(std::cin, command))
command = "quit";
if (command == "quit")
{
- Quit = true;
+ QuitRequest = true;
break;
}
else if (command == "ponderhit" || command == "stop")
std::string RootMove::pv_info_to_uci(const Position& pos, Value alpha, Value beta, int pvLine) {
- std::stringstream s;
+ std::stringstream s, l;
+ Move* m = pv;
+
+ while (*m != MOVE_NONE)
+ l << *m++ << " ";
s << "info depth " << Iteration // FIXME
+ << " seldepth " << int(m - pv)
<< " multipv " << pvLine + 1
<< " score " << value_to_uci(pv_score)
<< (pv_score >= beta ? " lowerbound" : pv_score <= alpha ? " upperbound" : "")
<< " time " << current_search_time()
<< " nodes " << pos.nodes_searched()
<< " nps " << nps(pos)
- << " pv ";
-
- for (Move* m = pv; *m != MOVE_NONE; m++)
- s << *m << " ";
+ << " pv " << l.str();
if (UseLogFile && pvLine == 0)
{
// This is the second order score that is used to compare the moves when
// the first order pv scores of both moves are equal.
- void RootMoveList::set_non_pv_scores(const Position& pos)
+ void RootMoveList::set_non_pv_scores(const Position& pos, Move ttm, SearchStack* ss)
{
Move move;
Value score = VALUE_ZERO;
- MovePicker mp(pos, MOVE_NONE, ONE_PLY, H);
+ MovePicker mp(pos, ttm, ONE_PLY, H, ss);
while ((move = mp.get_next_move()) != MOVE_NONE)
for (Base::iterator it = begin(); it != end(); ++it)
}
}
+ // Overload operator << to make it easier to print moves in coordinate notation
+ // (g1f3, a7a8q, etc.). The only special case is castling moves, where we
+ // print in the e1g1 notation in normal chess mode, and in e1h1 notation in
+ // Chess960 mode.
+
+ std::ostream& operator<<(std::ostream& os, Move m) {
+
+ Square from = move_from(m);
+ Square to = move_to(m);
+ bool chess960 = (os.iword(0) != 0); // See set960()
+
+ if (m == MOVE_NONE)
+ return os << "(none)";
+
+ if (m == MOVE_NULL)
+ return os << "0000";
+
+ if (move_is_short_castle(m) && !chess960)
+ return os << (from == SQ_E1 ? "e1g1" : "e8g8");
+
+ if (move_is_long_castle(m) && !chess960)
+ return os << (from == SQ_E1 ? "e1c1" : "e8c8");
+
+ os << square_to_string(from) << square_to_string(to);
+
+ if (move_is_promotion(m))
+ os << char(tolower(piece_type_to_char(move_promotion_piece(m))));
+
+ return os;
+ }
+
} // namespace
projects / stockfish / blobdiff