Rename lock.h to platform.h

[stockfish] / src / thread.h

diff --git a/src/thread.h b/src/thread.h
index 0a28f39bf5dc2f9bbf328acf12192eb5d7b1fe70..e71db835734d7bd2bc146b0cf71332e0d9b6ca61 100644 (file)
--- a/src/thread.h
+++ b/src/thread.h
@@ -1,7 +1,7 @@
 /*
   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
@@ -17,78 +17,120 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-
 #if !defined(THREAD_H_INCLUDED)
 #define THREAD_H_INCLUDED
 
+#include <set>
 
-////
-//// Includes
-////
-
-#include <cstring>
-
-#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 ACTIVE_SPLIT_POINTS_MAX = 8;
-
-
-////
-//// Types
-////
+const int MAX_THREADS = 32;
+const int MAX_SPLITPOINTS_PER_THREAD = 8;
 
 struct SplitPoint {
 
-  // Const data after splitPoint has been setup
-  SplitPoint* parent;
+  // Const data after split point has been setup
   const Position* pos;
+  const Search::Stack* ss;
   Depth depth;
-  bool pvNode, mateThreat;
   Value beta;
-  SearchStack sstack[MAX_THREADS][PLY_MAX_PLUS_2];
+  int nodeType;
+  int master;
+  Move threatMove;
 
   // Const pointers to shared data
   MovePicker* mp;
-  SearchStack* parentSstack;
+  SplitPoint* parent;
+
 
   // Shared data
   Lock lock;
+  volatile uint64_t slavesMask;
+  volatile int64_t nodes;
   volatile Value alpha;
   volatile Value bestValue;
+  volatile Move bestMove;
   volatile int moveCount;
-  volatile bool stopRequest;
-  volatile int slaves[MAX_THREADS];
+  volatile bool cutoff;
 };
 
-// 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 {
-  SplitPoint* volatile splitPoint;
-  volatile int activeSplitPoints;
-  uint64_t nodes;
-  uint64_t betaCutOffs[2];
-  volatile ThreadState state;
-  unsigned char pad[64]; // set some distance among local data for each thread
+
+  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();
+  void wait_for_stop_or_ponderhit();
+
+  SplitPoint splitPoints[MAX_SPLITPOINTS_PER_THREAD];
+  MaterialInfoTable materialTable;
+  PawnInfoTable pawnTable;
+  int threadID;
+  int maxPly;
+  Lock sleepLock;
+  WaitCondition sleepCond;
+  ThreadHandle handle;
+  SplitPoint* volatile curSplitPoint;
+  volatile int splitPointsCnt;
+  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 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, Move* bestMove,
+              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 splitLock;
+  WaitCondition sleepCond;
+  Depth minimumSplitDepth;
+  int maxThreadsPerSplitPoint;
+  int activeThreads;
+  bool useSleepingThreads;
 };
 
+extern ThreadsManager Threads;
 
 #endif // !defined(THREAD_H_INCLUDED)