Don't allocate MAX_THREADS hash tables if not necessary

[stockfish] / src / thread.h

diff --git a/src/thread.h b/src/thread.h
index 348e5f676d7096855b14a523bae295da6e62524e..e5a198c88e764902d74ff6f509c4ef4075cefbb5 100644 (file)
--- a/src/thread.h
+++ b/src/thread.h
@@ -17,50 +17,35 @@
   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 "lock.h"
+#include "material.h"
 #include "movepick.h"
+#include "pawns.h"
 #include "position.h"
-#include "search.h"
-
 
-////
-//// Constants and variables
-////
-
-const int MAX_THREADS = 16;
+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;
+  bool pvNode;
   Value beta;
   int ply;
+  int master;
   Move threatMove;
-  SearchStack sstack[MAX_THREADS][PLY_MAX_PLUS_2];
 
   // Const pointers to shared data
   MovePicker* mp;
-  SearchStack* parentSstack;
+  SearchStack* ss;
 
   // Shared data
   Lock lock;
@@ -68,12 +53,11 @@ struct SplitPoint {
   volatile Value alpha;
   volatile Value bestValue;
   volatile int moveCount;
-  volatile bool stopRequest;
+  volatile bool betaCutoff;
   volatile int slaves[MAX_THREADS];
 };
 
 // ThreadState type is used to represent thread's current state
-
 enum ThreadState
 {
   THREAD_INITIALIZING,  // thread is initializing itself
@@ -84,12 +68,68 @@ enum ThreadState
   THREAD_TERMINATED     // we are quitting and thread is terminated
 };
 
+
+// We 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 {
+  MaterialInfoTable materialTable;
+  PawnInfoTable pawnTable;
+  int maxPly;
+  Lock sleepLock;
+  WaitCondition sleepCond;
   volatile ThreadState state;
   SplitPoint* volatile splitPoint;
   volatile int activeSplitPoints;
   SplitPoint splitPoints[MAX_ACTIVE_SPLIT_POINTS];
+
+  void wake_up() {
+    lock_grab(&sleepLock);
+    cond_signal(&sleepCond);
+    lock_release(&sleepLock);
+  }
+};
+
+
+// ThreadsManager class is used to handle 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_threads();
+  void exit_threads();
+  void init_hash_tables();
+
+  int min_split_depth() const { return minimumSplitDepth; }
+  int active_threads() const { return activeThreads; }
+  void set_active_threads(int cnt) { activeThreads = cnt; }
+
+  void read_uci_options();
+  bool available_thread_exists(int master) const;
+  bool thread_is_available(int slave, int master) const;
+  bool cutoff_at_splitpoint(int threadID) const;
+  void idle_loop(int threadID, SplitPoint* sp);
+
+  template <bool Fake>
+  void split(Position& pos, SearchStack* ss, Value* alpha, const Value beta, Value* bestValue,
+             Depth depth, Move threatMove, int moveCount, MovePicker* mp, bool pvNode);
+private:
+  Lock mpLock;
+  Depth minimumSplitDepth;
+  int maxThreadsPerSplitPoint;
+  bool useSleepingThreads;
+  int activeThreads;
+  volatile bool allThreadsShouldExit;
+  Thread threads[MAX_THREADS];
 };
 
+extern ThreadsManager ThreadsMgr;
 
 #endif // !defined(THREAD_H_INCLUDED)