Files
stockfish/src/thread.h
T
joergosterandStéphane Nicolet 44a7db0f9a Implement 'old' multipv search.
It seems to be a waste of time to loop through all remaining root moves
after finishing each PV line. This patch skips this until we have reached
the last PV line (this is the way it was done in Glaurung and very early
versions of Stockfish).

No functional change in Single PV mode.

MultiPV=3 STC and LTC tests
LLR: 2.95 (-2.94,2.94) [0.00,5.00]
Total: 3113 W: 1248 L: 1064 D: 801

LLR: 2.95 (-2.94,2.94) [0.00,5.00]
Total: 2260 W: 848 L: 679 D: 733

Bench: 5023629
2018-02-04 13:35:44 +01:00

124 lines
3.4 KiB
C++

/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
Copyright (C) 2015-2018 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
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Stockfish is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef THREAD_H_INCLUDED
#define THREAD_H_INCLUDED
#include <atomic>
#include <condition_variable>
#include <mutex>
#include <thread>
#include <vector>
#include "material.h"
#include "movepick.h"
#include "pawns.h"
#include "position.h"
#include "search.h"
#include "thread_win32.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
std::thread 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, multiPV;
int selDepth, nmp_ply, nmp_odd;
std::atomic<uint64_t> nodes, tbHits;
Position rootPos;
Search::RootMoves rootMoves;
Depth rootDepth, completedDepth;
CounterMoveHistory counterMoves;
ButterflyHistory mainHistory;
CapturePieceToHistory captureHistory;
ContinuationHistory contHistory;
};
/// MainThread is a derived class specific for main thread
struct MainThread : public Thread {
using Thread::Thread;
void search() override;
void check_time();
bool failedLow;
double bestMoveChanges, previousTimeReduction;
Value previousScore;
int callsCnt;
};
/// 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.
struct ThreadPool : public std::vector<Thread*> {
void start_thinking(Position&, StateListPtr&, const Search::LimitsType&, bool = false);
void clear();
void set(size_t);
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); }
std::atomic_bool stop, ponder, stopOnPonderhit;
private:
StateListPtr setupStates;
uint64_t accumulate(std::atomic<uint64_t> Thread::* member) const {
uint64_t sum = 0;
for (Thread* th : *this)
sum += (th->*member).load(std::memory_order_relaxed);
return sum;
}
};
extern ThreadPool Threads;
#endif // #ifndef THREAD_H_INCLUDED