template uint64_t Search::perft<true>(Position&, Depth);
-/// MainThread::think() is called by the main thread when the program receives
+/// MainThread::search() is called by the main thread when the program receives
/// the UCI 'go' command. It searches from root position and at the end prints
/// the "bestmove" to output.
-void MainThread::think() {
+void MainThread::search() {
Color us = rootPos.side_to_move();
Time.init(Limits, us, rootPos.game_ply());
{
th->maxPly = 0;
th->rootDepth = DEPTH_ZERO;
- th->searching = true;
if (th != this)
{
th->rootPos = Position(rootPos, th);
th->rootMoves = rootMoves;
- th->notify_one(); // Wake up the thread and start searching
+ th->start_searching();
}
}
- search(true); // Let's start searching!
-
- // Stop the threads
- Signals.stop = true;
-
- // Wait until all threads have finished
- for (Thread* th : Threads)
- if (th != this)
- th->wait_while(th->searching);
+ Thread::search(); // Let's start searching!
}
// When playing in 'nodes as time' mode, subtract the searched nodes from
wait(Signals.stop);
}
+ // Stop the threads if not already stopped
+ Signals.stop = true;
+
+ // Wait until all threads have finished
+ for (Thread* th : Threads)
+ if (th != this)
+ th->wait_for_search_finished();
+
// Check if there are threads with a better score than main thread.
Thread* bestThread = this;
for (Thread* th : Threads)
// repeatedly with increasing depth until the allocated thinking time has been
// consumed, user stops the search, or the maximum search depth is reached.
-void Thread::search(bool isMainThread) {
+void Thread::search() {
Stack stack[MAX_PLY+4], *ss = stack+2; // To allow referencing (ss-2) and (ss+2)
Value bestValue, alpha, beta, delta;
Move easyMove = MOVE_NONE;
+ bool isMainThread = (this == Threads.main());
std::memset(ss-2, 0, 5 * sizeof(Stack));
{
// Set up the new depth for the helper threads
if (!isMainThread)
- rootDepth = Threads.main()->rootDepth + Depth(int(2.2 * log(1 + this->idx)));
+ rootDepth = std::min(DEPTH_MAX - ONE_PLY, Threads.main()->rootDepth + Depth(int(2.2 * log(1 + this->idx))));
// Age out PV variability metric
if (isMainThread)
}
}
- searching = false;
- notify_one(); // Wake up main thread if is sleeping waiting for us
-
if (!isMainThread)
return;
assert(-VALUE_INFINITE <= alpha && alpha < beta && beta <= VALUE_INFINITE);
assert(PvNode || (alpha == beta - 1));
- assert(depth > DEPTH_ZERO);
+ assert(DEPTH_ZERO < depth && depth < DEPTH_MAX);
Move pv[MAX_PLY+1], quietsSearched[64];
StateInfo st;
ss->ply = (ss-1)->ply + 1;
// Check for available remaining time
- if (thisThread->resetCallsCnt.load(std::memory_order_relaxed))
+ if (thisThread->resetCalls.load(std::memory_order_relaxed))
{
- thisThread->resetCallsCnt = false;
+ thisThread->resetCalls = false;
thisThread->callsCnt = 0;
}
if (++thisThread->callsCnt > 4096)
{
for (Thread* th : Threads)
- th->resetCallsCnt = true;
+ th->resetCalls = true;
check_time();
}
continue;
// History based pruning
- if ( depth <= 3 * ONE_PLY
+ if ( depth <= 4 * ONE_PLY
+ && move != ss->killers[0]
&& thisThread->history[pos.moved_piece(move)][to_sq(move)] < VALUE_ZERO
&& cmh[pos.moved_piece(move)][to_sq(move)] < VALUE_ZERO)
continue;