using std::cout;
using std::endl;
using std::string;
+using Search::Signals;
+using Search::Limits;
+
+namespace Search {
+
+ volatile SignalsType Signals;
+ LimitsType Limits;
+ std::vector<Move> RootMoves;
+ Position RootPosition;
+}
namespace {
// RootMoveList struct is mainly a std::vector of RootMove objects
struct RootMoveList : public std::vector<RootMove> {
- void init(Position& pos, Move searchMoves[]);
+ void init(Position& pos, Move rootMoves[]);
RootMove* find(const Move& m, int startIndex = 0);
int bestMoveChanges;
int MultiPV, UCIMultiPV, MultiPVIdx;
// Time management variables
- volatile bool StopOnPonderhit, FirstRootMove, StopRequest, QuitRequest, AspirationFailLow;
TimeManager TimeMgr;
- SearchLimits Limits;
// Skill level adjustment
int SkillLevel;
/// Local functions
- Move id_loop(Position& pos, Move searchMoves[], Move* ponderMove);
+ Move id_loop(Position& pos, Move rootMoves[], Move* ponderMove);
template <NodeType NT>
Value search(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth);
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 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
/// init_search() is called during startup to initialize various lookup tables
-void init_search() {
+void Search::init() {
int d; // depth (ONE_PLY == 2)
int hd; // half depth (ONE_PLY == 1)
/// perft() is our utility to verify move generation. All the leaf nodes up to
/// the given depth are generated and counted and the sum returned.
-int64_t perft(Position& pos, Depth depth) {
+int64_t Search::perft(Position& pos, Depth depth) {
StateInfo st;
int64_t sum = 0;
/// variables, and calls id_loop(). It returns false when a "quit" command is
/// received during the search.
-bool think(Position& pos, const SearchLimits& limits, Move searchMoves[]) {
+void Search::think() {
static Book book; // Defined static to initialize the PRNG only once
+ Position& pos = RootPosition;
+
// Save "search start" time and reset elapsed time to zero
elapsed_search_time(get_system_time());
- // Initialize global search-related variables
- StopOnPonderhit = StopRequest = QuitRequest = AspirationFailLow = false;
- Limits = limits;
-
// Set output stream mode: normal or chess960. Castling notation is different
cout << set960(pos.is_chess960());
Move bookMove = book.probe(pos, Options["Best Book Move"].value<bool>());
if (bookMove != MOVE_NONE)
{
- if (Limits.ponder)
- wait_for_stop_or_ponderhit();
+ if (!Signals.stop && (Limits.ponder || Limits.infinite))
+ Threads.wait_for_stop_or_ponderhit();
cout << "bestmove " << bookMove << endl;
- return !QuitRequest;
+ return;
}
}
else
Threads.set_timer(100);
- // Start async mode to catch UCI commands sent to us while searching,
- // like "quit", "stop", etc.
- Threads.start_listener();
-
// We're ready to start thinking. Call the iterative deepening loop function
Move ponderMove = MOVE_NONE;
- Move bestMove = id_loop(pos, searchMoves, &ponderMove);
-
- // From now on any UCI command will be read in-sync with Threads.getline()
- Threads.stop_listener();
+ Move bestMove = id_loop(pos, &RootMoves[0], &ponderMove);
// Stop timer, no need to check for available time any more
Threads.set_timer(0);
// When we reach max depth we arrive here even without a StopRequest, but if
// we are pondering or in infinite search, we shouldn't print the best move
// before we are told to do so.
- if (!StopRequest && (Limits.ponder || Limits.infinite))
- wait_for_stop_or_ponderhit();
+ if (!Signals.stop && (Limits.ponder || Limits.infinite))
+ Threads.wait_for_stop_or_ponderhit();
// Could be MOVE_NONE when searching on a stalemate position
cout << "bestmove " << bestMove;
cout << " ponder " << ponderMove;
cout << endl;
-
- return !QuitRequest;
}
// with increasing depth until the allocated thinking time has been consumed,
// user stops the search, or the maximum search depth is reached.
- Move id_loop(Position& pos, Move searchMoves[], Move* ponderMove) {
+ Move id_loop(Position& pos, Move rootMoves[], Move* ponderMove) {
SearchStack ss[PLY_MAX_PLUS_2];
Value bestValues[PLY_MAX_PLUS_2];
ss->currentMove = MOVE_NULL; // Hack to skip update gains
// Moves to search are verified and copied
- Rml.init(pos, searchMoves);
+ Rml.init(pos, rootMoves);
// Handle special case of searching on a mate/stalemate position
if (!Rml.size())
}
// Iterative deepening loop until requested to stop or target depth reached
- while (!StopRequest && ++depth <= PLY_MAX && (!Limits.maxDepth || depth <= Limits.maxDepth))
+ while (!Signals.stop && ++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++)
// 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)
+ if (Signals.stop)
break;
// Send full PV info to GUI if we are going to leave the loop or
}
else if (bestValue <= alpha)
{
- AspirationFailLow = true;
- StopOnPonderhit = false;
+ Signals.failedLowAtRoot = true;
+ Signals.stopOnPonderhit = false;
alpha = std::max(alpha - aspirationDelta, -VALUE_INFINITE);
aspirationDelta += aspirationDelta / 2;
bestMoveNeverChanged = false;
// Do we have time for the next iteration? Can we stop searching now?
- if (!StopRequest && !StopOnPonderhit && Limits.useTimeManagement())
+ if (!Signals.stop && !Signals.stopOnPonderhit && Limits.useTimeManagement())
{
+ bool stop = false; // Local variable instead of the volatile Signals.stop
+
// Take in account some extra time if the best move has changed
if (depth > 4 && depth < 50)
TimeMgr.pv_instability(bestMoveChanges[depth], bestMoveChanges[depth - 1]);
// Stop search if most of available time is already consumed. We probably don't
// have enough time to search the first move at the next iteration anyway.
if (elapsed_search_time() > (TimeMgr.available_time() * 62) / 100)
- StopRequest = true;
+ stop = true;
// Stop search early if one move seems to be much better than others
if ( depth >= 10
- && !StopRequest
+ && !stop
&& ( bestMoveNeverChanged
|| elapsed_search_time() > (TimeMgr.available_time() * 40) / 100))
{
(ss+1)->excludedMove = MOVE_NONE;
if (v < rBeta)
- StopRequest = true;
+ stop = true;
}
- // If we are allowed to ponder do not stop the search now but keep pondering
- if (StopRequest && Limits.ponder) // FIXME Limits.ponder is racy
+ if (stop)
{
- StopRequest = false;
- StopOnPonderhit = true;
+ // If we are allowed to ponder do not stop the search now but
+ // keep pondering until GUI sends "ponderhit" or "stop".
+ if (Limits.ponder) // FIXME racing
+ Signals.stopOnPonderhit = true;
+ else
+ Signals.stop = true;
}
}
}
}
// Step 2. Check for aborted search and immediate draw
- if (( StopRequest
+ if (( Signals.stop
|| pos.is_draw<false>()
|| ss->ply > PLY_MAX) && !RootNode)
return VALUE_DRAW;
if (RootNode)
{
// This is used by time management
- FirstRootMove = (moveCount == 1);
+ Signals.firstRootMove = (moveCount == 1);
// Save the current node count before the move is searched
nodes = pos.nodes_searched();
// 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)
+ if (RootNode && !Signals.stop)
{
// Remember searched nodes counts for this move
RootMove* rm = Rml.find(move);
&& depth >= Threads.min_split_depth()
&& bestValue < beta
&& Threads.available_slave_exists(pos.thread())
- && !StopRequest
+ && !Signals.stop
&& !thread.cutoff_occurred())
bestValue = Threads.split<FakeSplit>(pos, ss, alpha, beta, bestValue, depth,
threatMove, moveCount, &mp, NT);
// Step 21. Update tables
// If the search is not aborted, update the transposition table,
// history counters, and killer moves.
- if (!SpNode && !StopRequest && !thread.cutoff_occurred())
+ if (!SpNode && !Signals.stop && !thread.cutoff_occurred())
{
move = bestValue <= oldAlpha ? MOVE_NONE : ss->bestMove;
vt = bestValue <= oldAlpha ? VALUE_TYPE_UPPER
}
- // wait_for_stop_or_ponderhit() is called when the maximum depth is reached
- // while the program is pondering. The point is to work around a wrinkle in
- // 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 (that raise StopRequest) is
- // sent, and return, after which the bestmove and pondermove will be printed.
-
- void wait_for_stop_or_ponderhit() {
-
- string cmd;
- StopOnPonderhit = true;
-
- while (!StopRequest)
- {
- Threads.getline(cmd);
- do_uci_async_cmd(cmd);
- }
- }
-
-
// When playing with strength handicap choose best move among the MultiPV set
// using a statistical rule dependent on SkillLevel. Idea by Heinz van Saanen.
/// RootMove and RootMoveList method's definitions
- void RootMoveList::init(Position& pos, Move searchMoves[]) {
+ void RootMoveList::init(Position& pos, Move rootMoves[]) {
Move* sm;
bestMoveChanges = 0;
// Generate all legal moves and add them to RootMoveList
for (MoveList<MV_LEGAL> ml(pos); !ml.end(); ++ml)
{
- // If we have a searchMoves[] list then verify the move
+ // If we have a rootMoves[] list then verify the move
// is in the list before to add it.
- for (sm = searchMoves; *sm && *sm != ml.move(); sm++) {}
+ for (sm = rootMoves; *sm && *sm != ml.move(); sm++) {}
- if (sm != searchMoves && *sm != ml.move())
+ if (sm != rootMoves && *sm != ml.move())
continue;
RootMove rm;
}
-// do_uci_async_cmd() is called by listener thread when in async mode and 'cmd'
-// input line is received from the GUI.
-
-void do_uci_async_cmd(const std::string& cmd) {
-
- if (cmd == "quit")
- QuitRequest = StopRequest = true;
-
- else if (cmd == "stop")
- StopRequest = true;
-
- else if (cmd == "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.
- Limits.ponder = false;
-
- if (StopOnPonderhit)
- StopRequest = true;
- }
-}
-
-
// do_timer_event() is called by the timer thread when the timer triggers
void do_timer_event() {
if (Limits.ponder)
return;
- bool stillAtFirstMove = FirstRootMove
- && !AspirationFailLow
+ bool stillAtFirstMove = Signals.firstRootMove
+ && !Signals.failedLowAtRoot
&& e > TimeMgr.available_time();
bool noMoreTime = e > TimeMgr.maximum_time()
if ( (Limits.useTimeManagement() && noMoreTime)
|| (Limits.maxTime && e >= Limits.maxTime)
/* missing nodes limit */ ) // FIXME
- StopRequest = true;
+ Signals.stop = true;
}
projects / stockfish / blobdiff