Increase thread stack for OS X (#2035)

[stockfish] / src / thread.h

diff --git a/src/thread.h b/src/thread.h
index 0a28f39bf5dc2f9bbf328acf12192eb5d7b1fe70..af506609ed9f1e1ee0610e19fe63044e13de23ad 100644 (file)
--- a/src/thread.h
+++ b/src/thread.h
@@ -1,7 +1,8 @@
 /*
   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) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, 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 +18,109 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-
-#if !defined(THREAD_H_INCLUDED)
+#ifndef THREAD_H_INCLUDED
 #define THREAD_H_INCLUDED
 
+#include <atomic>
+#include <condition_variable>
+#include <mutex>
+#include <thread>
+#include <vector>
 
-////
-//// Includes
-////
-
-#include <cstring>
-
-#include "lock.h"
+#include "material.h"
 #include "movepick.h"
+#include "pawns.h"
 #include "position.h"
 #include "search.h"
+#include "thread_win32_osx.h"
+
+
+/// Thread class keeps together all the thread-related stuff. 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.
+
+class Thread {
+
+  Mutex mutex;
+  ConditionVariable cv;
+  size_t idx;
+  bool exit = false, searching = true; // Set before starting std::thread
+  NativeThread stdThread;
+
+public:
+  explicit Thread(size_t);
+  virtual ~Thread();
+  virtual void search();
+  void clear();
+  void idle_loop();
+  void start_searching();
+  void wait_for_search_finished();
+
+  Pawns::Table pawnsTable;
+  Material::Table materialTable;
+  Endgames endgames;
+  size_t pvIdx, pvLast;
+  int selDepth, nmpMinPly;
+  Color nmpColor;
+  std::atomic<uint64_t> nodes, tbHits;
+
+  Position rootPos;
+  Search::RootMoves rootMoves;
+  Depth rootDepth, completedDepth;
+  CounterMoveHistory counterMoves;
+  ButterflyHistory mainHistory;
+  CapturePieceToHistory captureHistory;
+  ContinuationHistory continuationHistory;
+  Score contempt;
+};
+
 
+/// MainThread is a derived class specific for main thread
 
-////
-//// Constants and variables
-////
+struct MainThread : public Thread {
 
-const int MAX_THREADS = 8;
-const int ACTIVE_SPLIT_POINTS_MAX = 8;
+  using Thread::Thread;
 
+  void search() override;
+  void check_time();
 
-////
-//// Types
-////
+  double bestMoveChanges, previousTimeReduction;
+  Value previousScore;
+  int callsCnt;
+  bool stopOnPonderhit;
+  std::atomic_bool ponder;
+};
 
-struct SplitPoint {
 
-  // Const data after splitPoint has been setup
-  SplitPoint* parent;
-  const Position* pos;
-  Depth depth;
-  bool pvNode, mateThreat;
-  Value beta;
-  SearchStack sstack[MAX_THREADS][PLY_MAX_PLUS_2];
+/// ThreadPool struct handles all the threads-related stuff like init, starting,
+/// parking and, most importantly, launching a thread. All the access to threads
+/// is done through this class.
 
-  // Const pointers to shared data
-  MovePicker* mp;
-  SearchStack* parentSstack;
+struct ThreadPool : public std::vector<Thread*> {
 
-  // Shared data
-  Lock lock;
-  volatile Value alpha;
-  volatile Value bestValue;
-  volatile int moveCount;
-  volatile bool stopRequest;
-  volatile int slaves[MAX_THREADS];
-};
+  void start_thinking(Position&, StateListPtr&, const Search::LimitsType&, bool = false);
+  void clear();
+  void set(size_t);
 
-// ThreadState type is used to represent thread's current state
+  MainThread* main()        const { return static_cast<MainThread*>(front()); }
+  uint64_t nodes_searched() const { return accumulate(&Thread::nodes); }
+  uint64_t tb_hits()        const { return accumulate(&Thread::tbHits); }
 
-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
-};
+  std::atomic_bool stop;
+
+private:
+  StateListPtr setupStates;
+
+  uint64_t accumulate(std::atomic<uint64_t> Thread::* member) const {
 
-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
+    uint64_t sum = 0;
+    for (Thread* th : *this)
+        sum += (th->*member).load(std::memory_order_relaxed);
+    return sum;
+  }
 };
 
+extern ThreadPool Threads;
 
-#endif // !defined(THREAD_H_INCLUDED)
+#endif // #ifndef THREAD_H_INCLUDED