#include "pawns.h"
#include "position.h"
#include "search.h"
-
-struct Thread;
-
-const size_t MAX_THREADS = 128;
-const size_t MAX_SPLITPOINTS_PER_THREAD = 8;
-const size_t MAX_SLAVES_PER_SPLITPOINT = 4;
-
-#if !defined(NO_SPINLOCK)
-/// Spinlock class wraps low level atomic operations to provide a spin lock
-
-class Spinlock {
-
- std::atomic_int lock;
-
-public:
- Spinlock() { lock = 1; } // Init here to workaround a bug with MSVC 2013
- void acquire() {
- while (lock.fetch_sub(1, std::memory_order_acquire) != 1)
- while (lock.load(std::memory_order_relaxed) <= 0) {}
- }
- void release() { lock.store(1, std::memory_order_release); }
-};
-
-#else
-
-class Spinlock {
-
- std::mutex mutex;
-
-public:
- void acquire() { mutex.lock(); }
- void release() { mutex.unlock(); }
-};
-
-#endif
-
-/// SplitPoint struct stores information shared by the threads searching in
-/// parallel below the same split point. It is populated at splitting time.
-
-struct SplitPoint {
-
- // Const data after split point has been setup
- const Position* pos;
- Search::Stack* ss;
- Thread* master;
- Depth depth;
- Value beta;
- int nodeType;
- bool cutNode;
-
- // Const pointers to shared data
- MovePicker* movePicker;
- SplitPoint* parentSplitPoint;
-
- // Shared variable data
- Spinlock spinlock;
- std::bitset<MAX_THREADS> slavesMask;
- volatile bool allSlavesSearching;
- volatile uint64_t nodes;
- volatile Value alpha;
- volatile Value bestValue;
- volatile Move bestMove;
- volatile int moveCount;
- volatile bool cutoff;
-};
+#include "thread_win32.h"
/// ThreadBase struct is the base of the hierarchy from where we derive all the
/// specialized thread classes.
-struct ThreadBase {
+struct ThreadBase : public std::thread {
+ ThreadBase() { exit = false; }
virtual ~ThreadBase() = default;
virtual void idle_loop() = 0;
void notify_one();
- void wait_for(volatile const bool& b);
+ void wait(std::atomic<bool>& b);
+ void wait_while(std::atomic<bool>& b);
- std::thread nativeThread;
- std::mutex mutex;
- std::condition_variable sleepCondition;
- volatile bool exit = false;
+ Mutex mutex;
+ ConditionVariable sleepCondition;
+ std::atomic<bool> exit;
};
-/// 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
+/// Thread struct keeps together all the thread related stuff like locks, state,
+/// history and countermoves tables. 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.
Thread();
virtual void idle_loop();
- bool cutoff_occurred() const;
- bool can_join(const SplitPoint* sp) const;
+ void search(bool isMainThread = false);
- void split(Position& pos, Search::Stack* ss, Value alpha, Value beta, Value* bestValue, Move* bestMove,
- Depth depth, int moveCount, MovePicker* movePicker, int nodeType, bool cutNode);
-
- SplitPoint splitPoints[MAX_SPLITPOINTS_PER_THREAD];
Pawns::Table pawnsTable;
Material::Table materialTable;
Endgames endgames;
- Position* activePosition;
- size_t idx;
+ size_t idx, PVIdx;
int maxPly;
- SplitPoint* volatile activeSplitPoint;
- volatile size_t splitPointsSize;
- volatile bool searching;
+ std::atomic<bool> searching;
+
+ Position rootPos;
+ Search::RootMoveVector rootMoves;
+ Depth rootDepth;
+ HistoryStats history;
+ MovesStats counterMoves;
+ Depth completedDepth;
};
/// special threads: the main one and the recurring timer.
struct MainThread : public Thread {
+ MainThread() { thinking = true; } // Avoid a race with start_thinking()
virtual void idle_loop();
- volatile bool thinking = true; // Avoid a race with start_thinking()
+ void join();
+ void think();
+ std::atomic<bool> thinking;
};
struct TimerThread : public ThreadBase {
static const int Resolution = 5; // Millisec between two check_time() calls
virtual void idle_loop();
+ void check_time();
bool run = false;
};
/// ThreadPool struct handles all the threads related stuff like init, starting,
-/// parking and, most importantly, launching a slave thread at a split point.
+/// parking and, most importantly, launching a thread.
/// All the access to shared thread data is done through this class.
struct ThreadPool : public std::vector<Thread*> {
- void init(); // No c'tor and d'tor, threads rely on globals that should be
- void exit(); // initialized and are valid during the whole thread lifetime.
+ void init(); // No constructor and destructor, threads rely on globals that should
+ void exit(); // be initialized and valid during the whole thread lifetime.
MainThread* main() { return static_cast<MainThread*>(at(0)); }
void read_uci_options();
- Thread* available_slave(const SplitPoint* sp) const;
- void wait_for_think_finished();
void start_thinking(const Position&, const Search::LimitsType&, Search::StateStackPtr&);
-
- Depth minimumSplitDepth;
- Spinlock spinlock;
- std::condition_variable sleepCondition;
+ int64_t nodes_searched();
TimerThread* timer;
};