2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
4 Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
6 Stockfish is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 Stockfish is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
20 #if !defined(THREAD_H_INCLUDED)
21 #define THREAD_H_INCLUDED
32 const int MAX_THREADS = 32;
33 const int MAX_SPLITPOINTS_PER_THREAD = 8;
37 // Const data after split point has been setup
39 const Search::Stack* ss;
46 // Const pointers to shared data
53 volatile uint64_t slavesMask;
54 volatile int64_t nodes;
56 volatile Value bestValue;
57 volatile Move bestMove;
58 volatile int moveCount;
63 /// Thread struct keeps together all the thread related stuff like locks, state
64 /// and especially split points. We also use per-thread pawn and material hash
65 /// tables so that once we get a pointer to an entry its life time is unlimited
66 /// and we don't have to care about someone changing the entry under our feet.
70 Thread(const Thread&); // Only declared to disable the default ones
71 Thread& operator=(const Thread&); // that are not suitable in this case.
73 typedef void (Thread::* Fn) ();
80 bool cutoff_occurred() const;
81 bool is_available_to(int master) const;
82 void idle_loop(SplitPoint* sp_master);
83 void idle_loop() { idle_loop(NULL); } // Hack to allow storing in start_fn
86 void wait_for_stop_or_ponderhit();
88 SplitPoint splitPoints[MAX_SPLITPOINTS_PER_THREAD];
89 MaterialInfoTable materialTable;
90 PawnInfoTable pawnTable;
94 WaitCondition sleepCond;
97 SplitPoint* volatile curSplitPoint;
98 volatile int splitPointsCnt;
99 volatile bool is_searching;
100 volatile bool do_sleep;
101 volatile bool do_exit;
105 /// ThreadsManager class handles all the threads related stuff like init, starting,
106 /// parking and, the most important, launching a slave thread at a split point.
107 /// All the access to shared thread data is done through this class.
109 class ThreadsManager {
110 /* As long as the single ThreadsManager object is defined as a global we don't
111 need to explicitly initialize to zero its data members because variables with
112 static storage duration are automatically set to zero before enter main()
118 Thread& operator[](int id) { return *threads[id]; }
119 bool use_sleeping_threads() const { return useSleepingThreads; }
120 int min_split_depth() const { return minimumSplitDepth; }
121 int size() const { return (int)threads.size(); }
125 void read_uci_options();
126 bool available_slave_exists(int master) const;
127 void set_timer(int msec);
128 void stop_thinking();
129 void start_thinking(const Position& pos, const Search::LimitsType& limits,
130 const std::set<Move>& = std::set<Move>(), bool async = false);
133 Value split(Position& pos, Search::Stack* ss, Value alpha, Value beta, Value bestValue, Move* bestMove,
134 Depth depth, Move threatMove, int moveCount, MovePicker* mp, int nodeType);
138 std::vector<Thread*> threads;
141 WaitCondition sleepCond;
142 Depth minimumSplitDepth;
143 int maxThreadsPerSplitPoint;
144 bool useSleepingThreads;
147 extern ThreadsManager Threads;
149 #endif // !defined(THREAD_H_INCLUDED)