/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-
#if !defined(THREAD_H_INCLUDED)
#define THREAD_H_INCLUDED
-
-////
-//// Includes
-////
-
-#include <cstring>
+#include <set>
#include "lock.h"
+#include "material.h"
#include "movepick.h"
+#include "pawns.h"
#include "position.h"
#include "search.h"
-
-////
-//// Constants and variables
-////
-
-const int MAX_THREADS = 8;
+const int MAX_THREADS = 32;
const int MAX_ACTIVE_SPLIT_POINTS = 8;
-
-////
-//// Types
-////
-
struct SplitPoint {
// Const data after splitPoint has been setup
SplitPoint* parent;
const Position* pos;
Depth depth;
- bool pvNode, mateThreat;
Value beta;
+ int nodeType;
int ply;
+ int master;
Move threatMove;
- SearchStack sstack[MAX_THREADS][PLY_MAX_PLUS_2];
// Const pointers to shared data
MovePicker* mp;
- SearchStack* parentSstack;
+ Search::Stack* ss;
// Shared data
Lock lock;
+ volatile uint64_t slavesMask;
+ volatile int64_t nodes;
volatile Value alpha;
volatile Value bestValue;
volatile int moveCount;
- volatile bool stopRequest;
- volatile int slaves[MAX_THREADS];
+ volatile bool is_betaCutoff;
};
-// ThreadState type is used to represent thread's current state
-enum ThreadState
-{
- THREAD_SEARCHING, // thread is performing work
- THREAD_AVAILABLE, // thread is polling for work
- THREAD_SLEEPING, // we are not thinking, so thread is sleeping
- THREAD_BOOKED, // other thread (master) has booked us as a slave
- THREAD_WORKISWAITING, // master has ordered us to start
- THREAD_TERMINATED // we are quitting and thread is terminated
-};
+/// Thread struct keeps together all the thread related stuff like locks, state
+/// and especially split points. We also use per-thread pawn and material hash
+/// tables so that once we get a pointer to an entry its life time is unlimited
+/// and we don't have to care about someone changing the entry under our feet.
struct Thread {
- uint64_t nodes;
- uint64_t betaCutOffs[2];
- volatile ThreadState state;
+
+ void wake_up();
+ bool cutoff_occurred() const;
+ bool is_available_to(int master) const;
+ void idle_loop(SplitPoint* sp_master);
+ void main_loop();
+ void timer_loop();
+
+ SplitPoint splitPoints[MAX_ACTIVE_SPLIT_POINTS];
+ MaterialInfoTable materialTable;
+ PawnInfoTable pawnTable;
+ int threadID;
+ int maxPly;
+ Lock sleepLock;
+ WaitCondition sleepCond;
+ ThreadHandle handle;
SplitPoint* volatile splitPoint;
volatile int activeSplitPoints;
- SplitPoint splitPoints[MAX_ACTIVE_SPLIT_POINTS];
+ volatile bool is_searching;
+ volatile bool do_sleep;
+ volatile bool do_exit;
+};
+
+
+/// ThreadsManager class handles all the threads related stuff like init, starting,
+/// parking and, the most important, launching a slave thread at a split point.
+/// All the access to shared thread data is done through this class.
+
+class ThreadsManager {
+ /* As long as the single ThreadsManager object is defined as a global we don't
+ need to explicitly initialize to zero its data members because variables with
+ static storage duration are automatically set to zero before enter main()
+ */
+public:
+ Thread& operator[](int threadID) { return threads[threadID]; }
+ void init();
+ void exit();
+
+ bool use_sleeping_threads() const { return useSleepingThreads; }
+ int min_split_depth() const { return minimumSplitDepth; }
+ int size() const { return activeThreads; }
+
+ void set_size(int cnt);
+ void read_uci_options();
+ bool available_slave_exists(int master) const;
+ void set_timer(int msec);
+ void wait_for_stop_or_ponderhit();
+ void stop_thinking();
+ void start_thinking(const Position& pos, const Search::LimitsType& limits,
+ const std::set<Move>& = std::set<Move>(), bool async = false);
+
+ template <bool Fake>
+ Value split(Position& pos, Search::Stack* ss, Value alpha, Value beta, Value bestValue,
+ Depth depth, Move threatMove, int moveCount, MovePicker* mp, int nodeType);
+private:
+ friend struct Thread;
+
+ Thread threads[MAX_THREADS + 1]; // Last one is used as a timer
+ Lock threadsLock;
+ Depth minimumSplitDepth;
+ int maxThreadsPerSplitPoint;
+ int activeThreads;
+ bool useSleepingThreads;
+ WaitCondition sleepCond;
};
+extern ThreadsManager Threads;
#endif // !defined(THREAD_H_INCLUDED)