/*
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
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <cassert>
#include <iostream>
+#include "movegen.h"
#include "search.h"
#include "thread.h"
#include "ucioption.h"
-ThreadsManager Threads; // Global object definition
+using namespace Search;
+
+ThreadPool Threads; // Global object
namespace { extern "C" {
// start_routine() is the C function which is called when a new thread
- // is launched. It simply calls idle_loop() of the supplied thread. The
- // last two threads are dedicated to read input from GUI and to mimic a
- // timer, so they run in listener_loop() and timer_loop() respectively.
-
-#if defined(_MSC_VER)
- DWORD WINAPI start_routine(LPVOID thread) {
-#else
- void* start_routine(void* thread) {
-#endif
-
- if (((Thread*)thread)->threadID == 0)
- ((Thread*)thread)->main_loop();
-
- else if (((Thread*)thread)->threadID == MAX_THREADS)
- ((Thread*)thread)->timer_loop();
- else
- ((Thread*)thread)->idle_loop(NULL);
+ // is launched. It is a wrapper to the virtual function idle_loop().
- return 0;
- }
+ long start_routine(Thread* th) { th->idle_loop(); return 0; }
} }
-// wake_up() wakes up the thread, normally at the beginning of the search or,
-// if "sleeping threads" is used, when there is some work to do.
-
-void Thread::wake_up() {
-
- lock_grab(&sleepLock);
- cond_signal(&sleepCond);
- lock_release(&sleepLock);
-}
+// Thread c'tor starts a newly-created thread of execution that will call
+// the the virtual function idle_loop(), going immediately to sleep.
+Thread::Thread() : splitPoints() {
-// cutoff_occurred() checks whether a beta cutoff has occurred in the current
-// active split point, or in some ancestor of the split point.
+ is_searching = do_exit = false;
+ maxPly = splitPointsCnt = 0;
+ curSplitPoint = NULL;
+ idx = Threads.size();
-bool Thread::cutoff_occurred() const {
-
- for (SplitPoint* sp = splitPoint; sp; sp = sp->parent)
- if (sp->is_betaCutoff)
- return true;
- return false;
+ if (!thread_create(handle, start_routine, this))
+ {
+ std::cerr << "Failed to create thread number " << idx << std::endl;
+ ::exit(EXIT_FAILURE);
+ }
}
-// is_available_to() checks whether the thread is available to help the thread with
-// threadID "master" at a split point. An obvious requirement is that thread must be
-// idle. With more than two threads, this is not by itself sufficient: If the thread
-// is the master of some active split point, it is only available as a slave to the
-// threads which are busy searching the split point at the top of "slave"'s split
-// point stack (the "helpful master concept" in YBWC terminology).
-
-bool Thread::is_available_to(int master) const {
+// Thread d'tor waits for thread termination before to return
- if (is_searching)
- return false;
+Thread::~Thread() {
- // Make a local copy to be sure doesn't become zero under our feet while
- // testing next condition and so leading to an out of bound access.
- int localActiveSplitPoints = activeSplitPoints;
+ do_exit = true; // Search must be already finished
+ notify_one();
+ thread_join(handle); // Wait for thread termination
+}
- // No active split points means that the thread is available as a slave for any
- // other thread otherwise apply the "helpful master" concept if possible.
- if ( !localActiveSplitPoints
- || splitPoints[localActiveSplitPoints - 1].is_slave[master])
- return true;
- return false;
-}
+// TimerThread::idle_loop() is where the timer thread waits msec milliseconds
+// and then calls check_time(). If msec is 0 thread sleeps until is woken up.
+extern void check_time();
+void TimerThread::idle_loop() {
-// read_uci_options() updates number of active threads and other internal
-// parameters according to the UCI options values. It is called before
-// to start a new search.
+ while (!do_exit)
+ {
+ mutex.lock();
-void ThreadsManager::read_uci_options() {
+ if (!do_exit)
+ sleepCondition.wait_for(mutex, msec ? msec : INT_MAX);
- maxThreadsPerSplitPoint = Options["Maximum Number of Threads per Split Point"].value<int>();
- minimumSplitDepth = Options["Minimum Split Depth"].value<int>() * ONE_PLY;
- useSleepingThreads = Options["Use Sleeping Threads"].value<bool>();
+ mutex.unlock();
- set_size(Options["Threads"].value<int>());
+ if (msec)
+ check_time();
+ }
}
-// set_size() changes the number of active threads and raises do_sleep flag for
-// all the unused threads that will go immediately to sleep.
+// MainThread::idle_loop() is where the main thread is parked waiting to be started
+// when there is a new search. Main thread will launch all the slave threads.
-void ThreadsManager::set_size(int cnt) {
+void MainThread::idle_loop() {
- assert(cnt > 0 && cnt <= MAX_THREADS);
+ while (true)
+ {
+ mutex.lock();
- activeThreads = cnt;
+ is_finished = true; // Always return to sleep after a search
+ is_searching = false;
- for (int i = 1; i < MAX_THREADS; i++) // Ignore main thread
- if (i < activeThreads)
+ while (is_finished && !do_exit)
{
- // Dynamically allocate pawn and material hash tables according to the
- // number of active threads. This avoids preallocating memory for all
- // possible threads if only few are used as, for instance, on mobile
- // devices where memory is scarce and allocating for MAX_THREADS could
- // even result in a crash.
- threads[i].pawnTable.init();
- threads[i].materialTable.init();
-
- threads[i].do_sleep = false;
+ Threads.sleepCondition.notify_one(); // Wake up UI thread if needed
+ sleepCondition.wait(mutex);
}
- else
- threads[i].do_sleep = true;
-}
-
-
-// init() is called during startup. Initializes locks and condition variables
-// and launches all threads sending them immediately to sleep.
-void ThreadsManager::init() {
+ mutex.unlock();
- // Initialize sleep condition used to block waiting for end of searching
- cond_init(&sleepCond);
-
- // Initialize threads lock, used when allocating slaves during splitting
- lock_init(&threadsLock);
-
- // Initialize sleep and split point locks
- for (int i = 0; i <= MAX_THREADS; i++)
- {
- lock_init(&threads[i].sleepLock);
- cond_init(&threads[i].sleepCond);
+ if (do_exit)
+ return;
- for (int j = 0; j < MAX_ACTIVE_SPLIT_POINTS; j++)
- lock_init(&(threads[i].splitPoints[j].lock));
- }
+ is_searching = true;
- // Initialize main thread's associated data
- threads[0].pawnTable.init();
- threads[0].materialTable.init();
+ Search::think();
- // Create and launch all the threads, threads will go immediately to sleep
- for (int i = 0; i <= MAX_THREADS; i++)
- {
- threads[i].is_searching = false;
- threads[i].do_sleep = true;
- threads[i].threadID = i;
-
-#if defined(_MSC_VER)
- threads[i].handle = CreateThread(NULL, 0, start_routine, (LPVOID)&threads[i], 0, NULL);
- bool ok = (threads[i].handle != NULL);
-#else
- bool ok = (pthread_create(&threads[i].handle, NULL, start_routine, (void*)&threads[i]) == 0);
-#endif
-
- if (!ok)
- {
- std::cerr << "Failed to create thread number " << i << std::endl;
- ::exit(EXIT_FAILURE);
- }
+ assert(is_searching);
}
}
-// exit() is called to cleanly terminate the threads when the program finishes
+// Thread::notify_one() wakes up the thread, normally at split time
-void ThreadsManager::exit() {
+void Thread::notify_one() {
- for (int i = 0; i <= MAX_THREADS; i++)
- {
- threads[i].do_terminate = true;
- threads[i].wake_up();
-
- // Wait for slave termination
-#if defined(_MSC_VER)
- WaitForSingleObject(threads[i].handle, 0);
- CloseHandle(threads[i].handle);
-#else
- pthread_join(threads[i].handle, NULL);
-#endif
-
- // Now we can safely destroy locks and wait conditions
- lock_destroy(&threads[i].sleepLock);
- cond_destroy(&threads[i].sleepCond);
-
- for (int j = 0; j < MAX_ACTIVE_SPLIT_POINTS; j++)
- lock_destroy(&(threads[i].splitPoints[j].lock));
- }
-
- lock_destroy(&threadsLock);
- cond_destroy(&sleepCond);
+ mutex.lock();
+ sleepCondition.notify_one();
+ mutex.unlock();
}
-// available_slave_exists() tries to find an idle thread which is available as
-// a slave for the thread with threadID "master".
-
-bool ThreadsManager::available_slave_exists(int master) const {
+// Thread::wait_for() set the thread to sleep until condition 'b' turns true
- assert(master >= 0 && master < activeThreads);
+void Thread::wait_for(volatile const bool& b) {
- for (int i = 0; i < activeThreads; i++)
- if (i != master && threads[i].is_available_to(master))
- return true;
-
- return false;
+ mutex.lock();
+ while (!b) sleepCondition.wait(mutex);
+ mutex.unlock();
}
-// split_point_finished() checks if all the slave threads of a given split
-// point have finished searching.
+// Thread::cutoff_occurred() checks whether a beta cutoff has occurred in the
+// current active split point, or in some ancestor of the split point.
-bool ThreadsManager::split_point_finished(SplitPoint* sp) const {
+bool Thread::cutoff_occurred() const {
- for (int i = 0; i < activeThreads; i++)
- if (sp->is_slave[i])
- return false;
+ for (SplitPoint* sp = curSplitPoint; sp; sp = sp->parent)
+ if (sp->cutoff)
+ return true;
- return true;
+ return false;
}
-// split() does the actual work of distributing the work at a node between
-// several available threads. If it does not succeed in splitting the
-// node (because no idle threads are available, or because we have no unused
-// split point objects), the function immediately returns. If splitting is
-// possible, a SplitPoint object is initialized with all the data that must be
-// copied to the helper threads and we tell our helper threads that they have
-// been assigned work. This will cause them to instantly leave their idle loops and
-// call search().When all threads have returned from search() then split() returns.
-
-template <bool Fake>
-Value ThreadsManager::split(Position& pos, SearchStack* ss, Value alpha, Value beta,
- Value bestValue, Depth depth, Move threatMove,
- int moveCount, MovePicker* mp, int nodeType) {
- assert(pos.pos_is_ok());
- assert(bestValue >= -VALUE_INFINITE);
- assert(bestValue <= alpha);
- assert(alpha < beta);
- assert(beta <= VALUE_INFINITE);
- assert(depth > DEPTH_ZERO);
- assert(pos.thread() >= 0 && pos.thread() < activeThreads);
- assert(activeThreads > 1);
-
- int i, master = pos.thread();
- Thread& masterThread = threads[master];
-
- // If we already have too many active split points, don't split
- if (masterThread.activeSplitPoints >= MAX_ACTIVE_SPLIT_POINTS)
- return bestValue;
+// Thread::is_available_to() checks whether the thread is available to help the
+// thread 'master' at a split point. An obvious requirement is that thread must
+// be idle. With more than two threads, this is not sufficient: If the thread is
+// the master of some active split point, it is only available as a slave to the
+// slaves which are busy searching the split point at the top of slaves split
+// point stack (the "helpful master concept" in YBWC terminology).
- // Pick the next available split point object from the split point stack
- SplitPoint* sp = masterThread.splitPoints + masterThread.activeSplitPoints;
-
- // Initialize the split point object
- sp->parent = masterThread.splitPoint;
- sp->master = master;
- sp->is_betaCutoff = false;
- sp->depth = depth;
- sp->threatMove = threatMove;
- sp->alpha = alpha;
- sp->beta = beta;
- sp->nodeType = nodeType;
- sp->bestValue = bestValue;
- sp->mp = mp;
- sp->moveCount = moveCount;
- sp->pos = &pos;
- sp->nodes = 0;
- sp->ss = ss;
- for (i = 0; i < activeThreads; i++)
- sp->is_slave[i] = false;
-
- // If we are here it means we are not available
- assert(masterThread.is_searching);
-
- int workersCnt = 1; // At least the master is included
+bool Thread::is_available_to(Thread* master) const {
- // Try to allocate available threads and ask them to start searching setting
- // the state to Thread::WORKISWAITING, this must be done under lock protection
- // to avoid concurrent allocation of the same slave by another master.
- lock_grab(&threadsLock);
+ if (is_searching)
+ return false;
- for (i = 0; !Fake && i < activeThreads && workersCnt < maxThreadsPerSplitPoint; i++)
- if (i != master && threads[i].is_available_to(master))
- {
- workersCnt++;
- sp->is_slave[i] = true;
- threads[i].splitPoint = sp;
+ // Make a local copy to be sure doesn't become zero under our feet while
+ // testing next condition and so leading to an out of bound access.
+ int spCnt = splitPointsCnt;
- // This makes the slave to exit from idle_loop()
- threads[i].is_searching = true;
+ // No active split points means that the thread is available as a slave for any
+ // other thread otherwise apply the "helpful master" concept if possible.
+ return !spCnt || (splitPoints[spCnt - 1].slavesMask & (1ULL << master->idx));
+}
- if (useSleepingThreads)
- threads[i].wake_up();
- }
- lock_release(&threadsLock);
+// init() is called at startup. Initializes lock and condition variable and
+// launches requested threads sending them immediately to sleep. We cannot use
+// a c'tor becuase Threads is a static object and we need a fully initialized
+// engine at this point due to allocation of endgames in Thread c'tor.
- // We failed to allocate even one slave, return
- if (!Fake && workersCnt == 1)
- return bestValue;
+void ThreadPool::init() {
- masterThread.splitPoint = sp;
- masterThread.activeSplitPoints++;
+ sleepWhileIdle = true;
+ timer = new TimerThread();
+ threads.push_back(new MainThread());
+ read_uci_options();
+}
- // Everything is set up. The master thread enters the idle loop, from which
- // it will instantly launch a search, because its is_searching flag is set.
- // We pass the split point as a parameter to the idle loop, which means that
- // the thread will return from the idle loop when all slaves have finished
- // their work at this split point.
- masterThread.idle_loop(sp);
- // In helpful master concept a master can help only a sub-tree, and
- // because here is all finished is not possible master is booked.
- assert(!masterThread.is_searching);
+// exit() cleanly terminates the threads before the program exits.
- // We have returned from the idle loop, which means that all threads are
- // finished. Note that changing state and decreasing activeSplitPoints is done
- // under lock protection to avoid a race with Thread::is_available_to().
- lock_grab(&threadsLock);
+void ThreadPool::exit() {
- masterThread.is_searching = true;
- masterThread.activeSplitPoints--;
+ delete timer; // As first becuase check_time() accesses threads data
- lock_release(&threadsLock);
+ for (size_t i = 0; i < threads.size(); i++)
+ delete threads[i];
+}
- masterThread.splitPoint = sp->parent;
- pos.set_nodes_searched(pos.nodes_searched() + sp->nodes);
- return sp->bestValue;
-}
+// read_uci_options() updates internal threads parameters from the corresponding
+// UCI options and creates/destroys threads to match the requested number. Thread
+// objects are dynamically allocated to avoid creating in advance all possible
+// threads, with included pawns and material tables, if only few are used.
-// Explicit template instantiations
-template Value ThreadsManager::split<false>(Position&, SearchStack*, Value, Value, Value, Depth, Move, int, MovePicker*, int);
-template Value ThreadsManager::split<true>(Position&, SearchStack*, Value, Value, Value, Depth, Move, int, MovePicker*, int);
+void ThreadPool::read_uci_options() {
+ maxThreadsPerSplitPoint = Options["Max Threads per Split Point"];
+ minimumSplitDepth = Options["Min Split Depth"] * ONE_PLY;
+ size_t requested = Options["Threads"];
-// Thread::timer_loop() is where the timer thread waits maxPly milliseconds
-// and then calls do_timer_event().
+ assert(requested > 0);
-void Thread::timer_loop() {
+ while (threads.size() < requested)
+ threads.push_back(new Thread());
- while (!do_terminate)
+ while (threads.size() > requested)
{
- lock_grab(&sleepLock);
- timed_wait(&sleepCond, &sleepLock, maxPly ? maxPly : INT_MAX);
- lock_release(&sleepLock);
- do_timer_event();
+ delete threads.back();
+ threads.pop_back();
}
}
-// ThreadsManager::set_timer() is used to set the timer to trigger after msec
-// milliseconds. If msec is 0 then timer is stopped.
+// available_slave_exists() tries to find an idle thread which is available as
+// a slave for the thread 'master'.
-void ThreadsManager::set_timer(int msec) {
+bool ThreadPool::available_slave_exists(Thread* master) const {
- Thread& timer = threads[MAX_THREADS];
+ for (size_t i = 0; i < threads.size(); i++)
+ if (threads[i]->is_available_to(master))
+ return true;
- lock_grab(&timer.sleepLock);
- timer.maxPly = msec;
- cond_signal(&timer.sleepCond); // Wake up and restart the timer
- lock_release(&timer.sleepLock);
+ return false;
}
-// Thread::main_loop() is where the main thread is parked waiting to be started
-// when there is a new search. Main thread will launch all the slave threads.
+// split() does the actual work of distributing the work at a node between
+// several available threads. If it does not succeed in splitting the node
+// (because no idle threads are available, or because we have no unused split
+// point objects), the function immediately returns. If splitting is possible, a
+// SplitPoint object is initialized with all the data that must be copied to the
+// helper threads and then helper threads are told that they have been assigned
+// work. This will cause them to instantly leave their idle loops and call
+// search(). When all threads have returned from search() then split() returns.
-void Thread::main_loop() {
+template <bool Fake>
+Value ThreadPool::split(Position& pos, Stack* ss, Value alpha, Value beta,
+ Value bestValue, Move* bestMove, Depth depth, Move threatMove,
+ int moveCount, MovePicker& mp, int nodeType) {
- while (true)
- {
- lock_grab(&sleepLock);
+ assert(pos.pos_is_ok());
+ assert(bestValue > -VALUE_INFINITE);
+ assert(bestValue <= alpha);
+ assert(alpha < beta);
+ assert(beta <= VALUE_INFINITE);
+ assert(depth > DEPTH_ZERO);
- do_sleep = true; // Always return to sleep after a search
+ Thread* master = pos.this_thread();
- is_searching = false;
+ if (master->splitPointsCnt >= MAX_SPLITPOINTS_PER_THREAD)
+ return bestValue;
+
+ // Pick the next available split point from the split point stack
+ SplitPoint& sp = master->splitPoints[master->splitPointsCnt];
+
+ sp.parent = master->curSplitPoint;
+ sp.master = master;
+ sp.cutoff = false;
+ sp.slavesMask = 1ULL << master->idx;
+ sp.depth = depth;
+ sp.bestMove = *bestMove;
+ sp.threatMove = threatMove;
+ sp.alpha = alpha;
+ sp.beta = beta;
+ sp.nodeType = nodeType;
+ sp.bestValue = bestValue;
+ sp.mp = ∓
+ sp.moveCount = moveCount;
+ sp.pos = &pos;
+ sp.nodes = 0;
+ sp.ss = ss;
+
+ assert(master->is_searching);
+
+ master->curSplitPoint = &sp;
+ int slavesCnt = 0;
- while (do_sleep && !do_terminate)
+ // Try to allocate available threads and ask them to start searching setting
+ // is_searching flag. This must be done under lock protection to avoid concurrent
+ // allocation of the same slave by another master.
+ mutex.lock();
+ sp.mutex.lock();
+
+ for (size_t i = 0; i < threads.size() && !Fake; ++i)
+ if (threads[i]->is_available_to(master))
{
- cond_signal(&Threads.sleepCond); // Wake up UI thread if needed
- cond_wait(&sleepCond, &sleepLock);
+ sp.slavesMask |= 1ULL << i;
+ threads[i]->curSplitPoint = &sp;
+ threads[i]->is_searching = true; // Slave leaves idle_loop()
+ threads[i]->notify_one(); // Could be sleeping
+
+ if (++slavesCnt + 1 >= maxThreadsPerSplitPoint) // Master is always included
+ break;
}
- is_searching = true;
+ master->splitPointsCnt++;
- lock_release(&sleepLock);
+ sp.mutex.unlock();
+ mutex.unlock();
- if (do_terminate)
- return;
+ // Everything is set up. The master thread enters the idle loop, from which
+ // it will instantly launch a search, because its is_searching flag is set.
+ // The thread will return from the idle loop when all slaves have finished
+ // their work at this split point.
+ if (slavesCnt || Fake)
+ {
+ master->Thread::idle_loop(); // Force a call to base class idle_loop()
- Search::think();
+ // In helpful master concept a master can help only a sub-tree of its split
+ // point, and because here is all finished is not possible master is booked.
+ assert(!master->is_searching);
}
-}
-
-// ThreadsManager::start_thinking() is used by UI thread to wake up the main
-// thread parked in main_loop() and starting a new search. If asyncMode is true
-// then function returns immediately, otherwise caller is blocked waiting for
-// the search to finish.
+ // We have returned from the idle loop, which means that all threads are
+ // finished. Note that setting is_searching and decreasing splitPointsCnt is
+ // done under lock protection to avoid a race with Thread::is_available_to().
+ mutex.lock();
+ sp.mutex.lock();
-void ThreadsManager::start_thinking(const Position& pos, const Search::LimitsType& limits,
- const std::vector<Move>& searchMoves, bool asyncMode) {
- Thread& main = threads[0];
+ master->is_searching = true;
+ master->splitPointsCnt--;
+ master->curSplitPoint = sp.parent;
+ pos.set_nodes_searched(pos.nodes_searched() + sp.nodes);
+ *bestMove = sp.bestMove;
- lock_grab(&main.sleepLock);
+ sp.mutex.unlock();
+ mutex.unlock();
- // Wait main thread has finished before to launch a new search
- while (!main.do_sleep)
- cond_wait(&sleepCond, &main.sleepLock);
+ return sp.bestValue;
+}
- // Copy input arguments to Search global variables
- Search::RootPosition.copy(pos, 0);
- Search::Limits = limits;
- Search::RootMoves = searchMoves;
+// Explicit template instantiations
+template Value ThreadPool::split<false>(Position&, Stack*, Value, Value, Value, Move*, Depth, Move, int, MovePicker&, int);
+template Value ThreadPool::split<true>(Position&, Stack*, Value, Value, Value, Move*, Depth, Move, int, MovePicker&, int);
- // Reset signals before to start the search
- memset((void*)&Search::Signals, 0, sizeof(Search::Signals));
- main.do_sleep = false;
- cond_signal(&main.sleepCond); // Wake up main thread
+// wait_for_search_finished() waits for main thread to go to sleep, this means
+// search is finished. Then returns.
- if (!asyncMode)
- cond_wait(&sleepCond, &main.sleepLock);
+void ThreadPool::wait_for_search_finished() {
- lock_release(&main.sleepLock);
+ MainThread* t = main_thread();
+ t->mutex.lock();
+ while (!t->is_finished) sleepCondition.wait(t->mutex);
+ t->mutex.unlock();
}
-// ThreadsManager::wait_for_stop_or_ponderhit() is called when the maximum depth
-// is reached while the program is pondering. The point is to work around a wrinkle
-// in the UCI protocol: When pondering, the engine is not allowed to give a
-// "bestmove" before the GUI sends it a "stop" or "ponderhit" command.
-// We simply wait here until one of these commands (that raise StopRequest) is
-// sent, and return, after which the bestmove and pondermove will be printed.
+// start_searching() wakes up the main thread sleeping in main_loop() so to start
+// a new search, then returns immediately.
-void ThreadsManager::wait_for_stop_or_ponderhit() {
+void ThreadPool::start_searching(const Position& pos, const LimitsType& limits,
+ const std::vector<Move>& searchMoves, StateStackPtr& states) {
+ wait_for_search_finished();
- Search::Signals.stopOnPonderhit = true;
+ SearchTime = Time::now(); // As early as possible
- Thread& main = threads[0];
+ Signals.stopOnPonderhit = Signals.firstRootMove = false;
+ Signals.stop = Signals.failedLowAtRoot = false;
- lock_grab(&main.sleepLock);
+ RootPos = pos;
+ Limits = limits;
+ SetupStates = states; // Ownership transfer here
+ RootMoves.clear();
- while (!Search::Signals.stop)
- cond_wait(&main.sleepCond, &main.sleepLock);
+ for (MoveList<LEGAL> ml(pos); !ml.end(); ++ml)
+ if (searchMoves.empty() || count(searchMoves.begin(), searchMoves.end(), ml.move()))
+ RootMoves.push_back(RootMove(ml.move()));
- lock_release(&main.sleepLock);
+ main_thread()->is_finished = false;
+ main_thread()->notify_one(); // Starts main thread
}
projects / stockfish / blobdiff