namespace {
- // Maximum number of allowed moves per position
- const int MOVES_MAX = 256;
-
// Types
enum NodeType { NonPV, PV };
bool available_thread_exists(int master) const;
bool thread_is_available(int slave, int master) const;
bool thread_should_stop(int threadID) const;
- void wake_sleeping_threads();
- void put_threads_to_sleep();
+ void wake_sleeping_thread(int threadID);
void idle_loop(int threadID, SplitPoint* sp);
template <bool Fake>
void split(const Position& pos, SearchStack* ss, int ply, Value* alpha, const Value beta, Value* bestValue,
- Depth depth, Move threatMove, bool mateThreat, int* moveCount, MovePicker* mp, bool pvNode);
+ Depth depth, Move threatMove, bool mateThreat, int moveCount, MovePicker* mp, bool pvNode);
private:
friend void poll();
int ActiveThreads;
- volatile bool AllThreadsShouldExit, AllThreadsShouldSleep;
+ volatile bool AllThreadsShouldExit;
Thread threads[MAX_THREADS];
-
- Lock MPLock, WaitLock;
-
-#if !defined(_MSC_VER)
- pthread_cond_t WaitCond;
-#else
- HANDLE SitIdleEvent[MAX_THREADS];
-#endif
-
+ Lock MPLock;
+ WaitCondition WaitCond[MAX_THREADS];
};
// Dynamic razoring margin based on depth
inline Value razor_margin(Depth d) { return Value(0x200 + 0x10 * int(d)); }
- // Step 8. Null move search with verification search
-
- // Null move margin. A null move search will not be done if the static
- // evaluation of the position is more than NullMoveMargin below beta.
- const Value NullMoveMargin = Value(0x200);
-
// Maximum depth for use of dynamic threat detection when null move fails low
const Depth ThreatDepth = 5 * ONE_PLY;
Value id_loop(const Position& pos, Move searchMoves[]);
Value root_search(Position& pos, SearchStack* ss, Move* pv, RootMoveList& rml, Value* alphaPtr, Value* betaPtr);
- template <NodeType PvNode>
+ template <NodeType PvNode, bool SpNode>
Value search(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth, int ply);
template <NodeType PvNode>
- Value qsearch(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth, int ply);
+ inline Value search(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth, int ply) {
+ return search<PvNode, false>(pos, ss, alpha, beta, depth, ply);
+ }
template <NodeType PvNode>
- void sp_search(SplitPoint* sp, int threadID);
+ Value qsearch(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth, int ply);
template <NodeType PvNode>
Depth extension(const Position& pos, Move m, bool captureOrPromotion, bool moveIsCheck, bool singleEvasion, bool mateThreat, bool* dangerous);
bool value_is_mate(Value value);
Value value_to_tt(Value v, int ply);
Value value_from_tt(Value v, int ply);
- bool move_is_killer(Move m, SearchStack* ss);
bool ok_to_use_TT(const TTEntry* tte, Depth depth, Value beta, int ply);
bool connected_threat(const Position& pos, Move m, Move threat);
Value refine_eval(const TTEntry* tte, Value defaultEval, int ply);
// Init futility move count array
for (d = 0; d < 32; d++)
- FutilityMoveCountArray[d] = 3 + (1 << (3 * d / 8));
+ FutilityMoveCountArray[d] = int(3.001 + 0.25 * pow(d, 2.0));
}
init_eval(ThreadsMgr.active_threads());
}
- // Wake up sleeping threads
- ThreadsMgr.wake_sleeping_threads();
-
// Set thinking time
int myTime = time[pos.side_to_move()];
int myIncrement = increment[pos.side_to_move()];
if (UseLogFile)
LogFile.close();
- ThreadsMgr.put_threads_to_sleep();
-
return !Quit;
}
// Add some extra time if the best move has changed during the last two iterations
if (Iteration > 5 && Iteration <= 50)
- TimeMgr.pv_unstability(BestMoveChangesByIteration[Iteration],
+ TimeMgr.pv_instability(BestMoveChangesByIteration[Iteration],
BestMoveChangesByIteration[Iteration-1]);
// Stop search if most of MaxSearchTime is consumed at the end of the
}
- // search<>() is the main search function for both PV and non-PV nodes
+ // search<>() is the main search function for both PV and non-PV nodes and for
+ // normal and SplitPoint nodes. When called just after a split point the search
+ // is simpler because we have already probed the hash table, done a null move
+ // search, and searched the first move before splitting, we don't have to repeat
+ // all this work again. We also don't need to store anything to the hash table
+ // here: This is taken care of after we return from the split point.
- template <NodeType PvNode>
+ template <NodeType PvNode, bool SpNode>
Value search(Position& pos, SearchStack* ss, Value alpha, Value beta, Depth depth, int ply) {
assert(alpha >= -VALUE_INFINITE && alpha <= VALUE_INFINITE);
bool mateThreat = false;
int moveCount = 0;
int threadID = pos.thread();
+ SplitPoint* sp = NULL;
refinedValue = bestValue = value = -VALUE_INFINITE;
oldAlpha = alpha;
+ isCheck = pos.is_check();
+
+ if (SpNode)
+ {
+ sp = ss->sp;
+ tte = NULL;
+ evalMargin = VALUE_ZERO;
+ ttMove = excludedMove = MOVE_NONE;
+ threatMove = sp->threatMove;
+ mateThreat = sp->mateThreat;
+ goto split_point_start;
+ }
// Step 1. Initialize node and poll. Polling can abort search
ThreadsMgr.incrementNodeCounter(threadID);
// Step 2. Check for aborted search and immediate draw
if (AbortSearch || ThreadsMgr.thread_should_stop(threadID))
- return VALUE_ZERO;
+ return VALUE_DRAW;
if (pos.is_draw() || ply >= PLY_MAX - 1)
return VALUE_DRAW;
// Step 5. Evaluate the position statically and
// update gain statistics of parent move.
- isCheck = pos.is_check();
if (isCheck)
ss->eval = evalMargin = VALUE_NONE;
else if (tte)
return refinedValue - futility_margin(depth, 0);
// Step 8. Null move search with verification search (is omitted in PV nodes)
- // When we jump directly to qsearch() we do a null move only if static value is
- // at least beta. Otherwise we do a null move if static value is not more than
- // NullMoveMargin under beta.
if ( !PvNode
&& !ss->skipNullMove
&& depth > ONE_PLY
&& !isCheck
- && refinedValue >= beta - (depth >= 4 * ONE_PLY ? NullMoveMargin : 0)
+ && refinedValue >= beta
&& !value_is_mate(beta)
&& pos.non_pawn_material(pos.side_to_move()))
{
if (PvNode)
mateThreat = pos.has_mate_threat();
+split_point_start: // At split points actual search starts from here
+
// Initialize a MovePicker object for the current position
- MovePicker mp = MovePicker(pos, ttMove, depth, H, ss, (PvNode ? -VALUE_INFINITE : beta));
+ // FIXME currently MovePicker() c'tor is needless called also in SplitPoint
+ MovePicker mpBase = MovePicker(pos, ttMove, depth, H, ss, (PvNode ? -VALUE_INFINITE : beta));
+ MovePicker& mp = SpNode ? *sp->mp : mpBase;
CheckInfo ci(pos);
ss->bestMove = MOVE_NONE;
- singleEvasion = isCheck && mp.number_of_evasions() == 1;
+ singleEvasion = !SpNode && isCheck && mp.number_of_evasions() == 1;
futilityBase = ss->eval + evalMargin;
- singularExtensionNode = depth >= SingularExtensionDepth[PvNode]
+ singularExtensionNode = !SpNode
+ && depth >= SingularExtensionDepth[PvNode]
&& tte
&& tte->move()
&& !excludedMove // Do not allow recursive singular extension search
&& (tte->type() & VALUE_TYPE_LOWER)
&& tte->depth() >= depth - 3 * ONE_PLY;
+ if (SpNode)
+ {
+ lock_grab(&(sp->lock));
+ bestValue = sp->bestValue;
+ }
// Step 10. Loop through moves
// Loop through all legal moves until no moves remain or a beta cutoff occurs
&& (move = mp.get_next_move()) != MOVE_NONE
&& !ThreadsMgr.thread_should_stop(threadID))
{
+ if (SpNode)
+ {
+ moveCount = ++sp->moveCount;
+ lock_release(&(sp->lock));
+ }
+
assert(move_is_ok(move));
if (move == excludedMove)
newDepth = depth - ONE_PLY + ext;
// Update current move (this must be done after singular extension search)
- movesSearched[moveCount++] = ss->currentMove = move;
+ movesSearched[moveCount] = ss->currentMove = move;
+
+ if (!SpNode)
+ moveCount++;
// Step 12. Futility pruning (is omitted in PV nodes)
if ( !PvNode
// Move count based pruning
if ( moveCount >= futility_move_count(depth)
&& !(threatMove && connected_threat(pos, move, threatMove))
- && bestValue > value_mated_in(PLY_MAX))
+ && bestValue > value_mated_in(PLY_MAX)) // FIXME bestValue is racy
+ {
+ if (SpNode)
+ lock_grab(&(sp->lock));
+
continue;
+ }
// Value based pruning
// We illogically ignore reduction condition depth >= 3*ONE_PLY for predicted depth,
if (futilityValueScaled < beta)
{
- if (futilityValueScaled > bestValue)
+ if (SpNode)
+ {
+ lock_grab(&(sp->lock));
+ if (futilityValueScaled > sp->bestValue)
+ sp->bestValue = bestValue = futilityValueScaled;
+ }
+ else if (futilityValueScaled > bestValue)
bestValue = futilityValueScaled;
+
continue;
}
}
// Step extra. pv search (only in PV nodes)
// The first move in list is the expected PV
- if (PvNode && moveCount == 1)
+ if (!SpNode && PvNode && moveCount == 1)
value = newDepth < ONE_PLY ? -qsearch<PV>(pos, ss+1, -beta, -alpha, DEPTH_ZERO, ply+1)
: - search<PV>(pos, ss+1, -beta, -alpha, newDepth, ply+1);
else
&& !captureOrPromotion
&& !dangerous
&& !move_is_castle(move)
- && !move_is_killer(move, ss))
+ && !(ss->killers[0] == move || ss->killers[1] == move))
{
ss->reduction = reduction<PvNode>(depth, moveCount);
if (ss->reduction)
{
+ alpha = SpNode ? sp->alpha : alpha;
Depth d = newDepth - ss->reduction;
value = d < ONE_PLY ? -qsearch<NonPV>(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO, ply+1)
: - search<NonPV>(pos, ss+1, -(alpha+1), -alpha, d, ply+1);
assert(newDepth - ONE_PLY >= ONE_PLY);
ss->reduction = ONE_PLY;
+ alpha = SpNode ? sp->alpha : alpha;
value = -search<NonPV>(pos, ss+1, -(alpha+1), -alpha, newDepth-ss->reduction, ply+1);
doFullDepthSearch = (value > alpha);
}
// Step 15. Full depth search
if (doFullDepthSearch)
{
+ alpha = SpNode ? sp->alpha : alpha;
value = newDepth < ONE_PLY ? -qsearch<NonPV>(pos, ss+1, -(alpha+1), -alpha, DEPTH_ZERO, ply+1)
: - search<NonPV>(pos, ss+1, -(alpha+1), -alpha, newDepth, ply+1);
assert(value > -VALUE_INFINITE && value < VALUE_INFINITE);
// Step 17. Check for new best move
- if (value > bestValue)
+ if (SpNode)
+ {
+ lock_grab(&(sp->lock));
+ bestValue = sp->bestValue;
+ alpha = sp->alpha;
+ }
+
+ if (value > bestValue && !(SpNode && ThreadsMgr.thread_should_stop(threadID)))
{
bestValue = value;
+
+ if (SpNode)
+ sp->bestValue = value;
+
if (value > alpha)
{
+ if (SpNode && (!PvNode || value >= beta))
+ sp->stopRequest = true;
+
if (PvNode && value < beta) // We want always alpha < beta
+ {
alpha = value;
+ if (SpNode)
+ sp->alpha = value;
+ }
- if (value == value_mate_in(ply + 1))
+ if (!SpNode && value == value_mate_in(ply + 1))
ss->mateKiller = move;
ss->bestMove = move;
+
+ if (SpNode)
+ sp->parentSstack->bestMove = move;
}
}
// Step 18. Check for split
- if ( depth >= MinimumSplitDepth
+ if ( !SpNode
+ && depth >= MinimumSplitDepth
&& ThreadsMgr.active_threads() > 1
&& bestValue < beta
&& ThreadsMgr.available_thread_exists(threadID)
&& !ThreadsMgr.thread_should_stop(threadID)
&& Iteration <= 99)
ThreadsMgr.split<FakeSplit>(pos, ss, ply, &alpha, beta, &bestValue, depth,
- threatMove, mateThreat, &moveCount, &mp, PvNode);
+ threatMove, mateThreat, moveCount, &mp, PvNode);
+ }
+
+ if (SpNode)
+ {
+ /* Here we have the lock still grabbed */
+ sp->slaves[threadID] = 0;
+ lock_release(&(sp->lock));
+ return bestValue;
}
// Step 19. Check for mate and stalemate
assert(tte->static_value() != VALUE_NONE);
evalMargin = tte->static_value_margin();
- bestValue = tte->static_value();
+ ss->eval = bestValue = tte->static_value();
}
else
- bestValue = evaluate(pos, evalMargin);
+ ss->eval = bestValue = evaluate(pos, evalMargin);
- ss->eval = bestValue;
update_gains(pos, (ss-1)->currentMove, (ss-1)->eval, ss->eval);
// Stand pat. Return immediately if static value is at least beta
deepChecks = (depth == -ONE_PLY && bestValue >= beta - PawnValueMidgame / 8);
// Futility pruning parameters, not needed when in check
- futilityBase = bestValue + FutilityMarginQS + evalMargin;
+ futilityBase = ss->eval + evalMargin + FutilityMarginQS;
enoughMaterial = pos.non_pawn_material(pos.side_to_move()) > RookValueMidgame;
}
}
}
- // Detect blocking evasions that are candidate to be pruned
+ // Detect non-capture evasions that are candidate to be pruned
evasionPrunable = isCheck
&& bestValue > value_mated_in(PLY_MAX)
&& !pos.move_is_capture(move)
- && pos.type_of_piece_on(move_from(move)) != KING
&& !pos.can_castle(pos.side_to_move());
// Don't search moves with negative SEE values
ValueType vt = (bestValue <= oldAlpha ? VALUE_TYPE_UPPER : bestValue >= beta ? VALUE_TYPE_LOWER : VALUE_TYPE_EXACT);
TT.store(pos.get_key(), value_to_tt(bestValue, ply), vt, d, ss->bestMove, ss->eval, evalMargin);
- // Update killers only for checking moves that fails high
- if ( bestValue >= beta
- && !pos.move_is_capture_or_promotion(ss->bestMove))
- update_killers(ss->bestMove, ss);
-
assert(bestValue > -VALUE_INFINITE && bestValue < VALUE_INFINITE);
return bestValue;
}
- // sp_search() is used to search from a split point. This function is called
- // by each thread working at the split point. It is similar to the normal
- // search() function, but simpler. Because we have already probed the hash
- // table, done a null move search, and searched the first move before
- // splitting, we don't have to repeat all this work in sp_search(). We
- // also don't need to store anything to the hash table here: This is taken
- // care of after we return from the split point.
-
- template <NodeType PvNode>
- void sp_search(SplitPoint* sp, int threadID) {
-
- assert(threadID >= 0 && threadID < ThreadsMgr.active_threads());
- assert(ThreadsMgr.active_threads() > 1);
-
- StateInfo st;
- Move move;
- Depth ext, newDepth;
- Value value;
- Value futilityValueScaled; // NonPV specific
- bool isCheck, moveIsCheck, captureOrPromotion, dangerous;
- int moveCount;
- value = -VALUE_INFINITE;
-
- Position pos(*sp->pos, threadID);
- CheckInfo ci(pos);
- SearchStack* ss = sp->sstack[threadID] + 1;
- isCheck = pos.is_check();
-
- // Step 10. Loop through moves
- // Loop through all legal moves until no moves remain or a beta cutoff occurs
- lock_grab(&(sp->lock));
-
- while ( sp->bestValue < sp->beta
- && (move = sp->mp->get_next_move()) != MOVE_NONE
- && !ThreadsMgr.thread_should_stop(threadID))
- {
- moveCount = ++sp->moveCount;
- lock_release(&(sp->lock));
-
- assert(move_is_ok(move));
-
- moveIsCheck = pos.move_is_check(move, ci);
- captureOrPromotion = pos.move_is_capture_or_promotion(move);
-
- // Step 11. Decide the new search depth
- ext = extension<PvNode>(pos, move, captureOrPromotion, moveIsCheck, false, sp->mateThreat, &dangerous);
- newDepth = sp->depth - ONE_PLY + ext;
-
- // Update current move
- ss->currentMove = move;
-
- // Step 12. Futility pruning (is omitted in PV nodes)
- if ( !PvNode
- && !captureOrPromotion
- && !isCheck
- && !dangerous
- && !move_is_castle(move))
- {
- // Move count based pruning
- if ( moveCount >= futility_move_count(sp->depth)
- && !(sp->threatMove && connected_threat(pos, move, sp->threatMove))
- && sp->bestValue > value_mated_in(PLY_MAX))
- {
- lock_grab(&(sp->lock));
- continue;
- }
-
- // Value based pruning
- Depth predictedDepth = newDepth - reduction<NonPV>(sp->depth, moveCount);
- futilityValueScaled = ss->eval + futility_margin(predictedDepth, moveCount)
- + H.gain(pos.piece_on(move_from(move)), move_to(move));
-
- if (futilityValueScaled < sp->beta)
- {
- lock_grab(&(sp->lock));
-
- if (futilityValueScaled > sp->bestValue)
- sp->bestValue = futilityValueScaled;
- continue;
- }
- }
-
- // Step 13. Make the move
- pos.do_move(move, st, ci, moveIsCheck);
-
- // Step 14. Reduced search
- // If the move fails high will be re-searched at full depth.
- bool doFullDepthSearch = true;
-
- if ( !captureOrPromotion
- && !dangerous
- && !move_is_castle(move)
- && !move_is_killer(move, ss))
- {
- ss->reduction = reduction<PvNode>(sp->depth, moveCount);
- if (ss->reduction)
- {
- Value localAlpha = sp->alpha;
- Depth d = newDepth - ss->reduction;
- value = d < ONE_PLY ? -qsearch<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, DEPTH_ZERO, sp->ply+1)
- : - search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, d, sp->ply+1);
-
- doFullDepthSearch = (value > localAlpha);
- }
-
- // The move failed high, but if reduction is very big we could
- // face a false positive, retry with a less aggressive reduction,
- // if the move fails high again then go with full depth search.
- if (doFullDepthSearch && ss->reduction > 2 * ONE_PLY)
- {
- assert(newDepth - ONE_PLY >= ONE_PLY);
-
- ss->reduction = ONE_PLY;
- Value localAlpha = sp->alpha;
- value = -search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, newDepth-ss->reduction, sp->ply+1);
- doFullDepthSearch = (value > localAlpha);
- }
- ss->reduction = DEPTH_ZERO; // Restore original reduction
- }
-
- // Step 15. Full depth search
- if (doFullDepthSearch)
- {
- Value localAlpha = sp->alpha;
- value = newDepth < ONE_PLY ? -qsearch<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, DEPTH_ZERO, sp->ply+1)
- : - search<NonPV>(pos, ss+1, -(localAlpha+1), -localAlpha, newDepth, sp->ply+1);
-
- // Step extra. pv search (only in PV nodes)
- // Search only for possible new PV nodes, if instead value >= beta then
- // parent node fails low with value <= alpha and tries another move.
- if (PvNode && value > localAlpha && value < sp->beta)
- value = newDepth < ONE_PLY ? -qsearch<PV>(pos, ss+1, -sp->beta, -sp->alpha, DEPTH_ZERO, sp->ply+1)
- : - search<PV>(pos, ss+1, -sp->beta, -sp->alpha, newDepth, sp->ply+1);
- }
-
- // Step 16. Undo move
- pos.undo_move(move);
-
- assert(value > -VALUE_INFINITE && value < VALUE_INFINITE);
-
- // Step 17. Check for new best move
- lock_grab(&(sp->lock));
-
- if (value > sp->bestValue && !ThreadsMgr.thread_should_stop(threadID))
- {
- sp->bestValue = value;
-
- if (sp->bestValue > sp->alpha)
- {
- if (!PvNode || value >= sp->beta)
- sp->stopRequest = true;
-
- if (PvNode && value < sp->beta) // This guarantees that always: sp->alpha < sp->beta
- sp->alpha = value;
-
- sp->parentSstack->bestMove = ss->bestMove = move;
- }
- }
- }
-
- /* Here we have the lock still grabbed */
-
- sp->slaves[threadID] = 0;
-
- lock_release(&(sp->lock));
- }
-
-
// connected_moves() tests whether two moves are 'connected' in the sense
// that the first move somehow made the second move possible (for instance
// if the moving piece is the same in both moves). The first move is assumed
}
- // move_is_killer() checks if the given move is among the killer moves
-
- bool move_is_killer(Move m, SearchStack* ss) {
-
- if (ss->killers[0] == m || ss->killers[1] == m)
- return true;
-
- return false;
- }
-
-
// extension() decides whether a move should be searched with normal depth,
// or with extended depth. Certain classes of moves (checking moves, in
// particular) are searched with bigger depth than ordinary moves and in
void update_history(const Position& pos, Move move, Depth depth,
Move movesSearched[], int moveCount) {
-
Move m;
H.success(pos.piece_on(move_from(move)), move_to(move), depth);
ss->excludedMove = MOVE_NONE;
ss->skipNullMove = false;
ss->reduction = DEPTH_ZERO;
+ ss->sp = NULL;
if (i < 3)
ss->killers[0] = ss->killers[1] = ss->mateKiller = MOVE_NONE;
// If we are not thinking, wait for a condition to be signaled
// instead of wasting CPU time polling for work.
- while (AllThreadsShouldSleep || threadID >= ActiveThreads)
+ while ( threadID >= ActiveThreads
+ || threads[threadID].state == THREAD_INITIALIZING
+ || (!sp && threads[threadID].state == THREAD_AVAILABLE))
{
assert(!sp);
assert(threadID != 0);
- threads[threadID].state = THREAD_SLEEPING;
-#if !defined(_MSC_VER)
- lock_grab(&WaitLock);
- if (AllThreadsShouldSleep || threadID >= ActiveThreads)
- pthread_cond_wait(&WaitCond, &WaitLock);
- lock_release(&WaitLock);
-#else
- WaitForSingleObject(SitIdleEvent[threadID], INFINITE);
-#endif
- }
+ if (AllThreadsShouldExit)
+ break;
+
+ lock_grab(&MPLock);
- // If thread has just woken up, mark it as available
- if (threads[threadID].state == THREAD_SLEEPING)
+ // Retest condition under lock protection
+ if (!( threadID >= ActiveThreads
+ || threads[threadID].state == THREAD_INITIALIZING
+ || (!sp && threads[threadID].state == THREAD_AVAILABLE)))
+ {
+ lock_release(&MPLock);
+ continue;
+ }
+
+ // Put thread to sleep
threads[threadID].state = THREAD_AVAILABLE;
+ cond_wait(&WaitCond[threadID], &MPLock);
+ lock_release(&MPLock);
+ }
// If this thread has been assigned work, launch a search
if (threads[threadID].state == THREAD_WORKISWAITING)
{
- assert(!AllThreadsShouldExit && !AllThreadsShouldSleep);
+ assert(!AllThreadsShouldExit);
threads[threadID].state = THREAD_SEARCHING;
- if (threads[threadID].splitPoint->pvNode)
- sp_search<PV>(threads[threadID].splitPoint, threadID);
- else
- sp_search<NonPV>(threads[threadID].splitPoint, threadID);
+ // Here we call search() with SplitPoint template parameter set to true
+ SplitPoint* tsp = threads[threadID].splitPoint;
+ Position pos(*tsp->pos, threadID);
+ SearchStack* ss = tsp->sstack[threadID] + 1;
+ ss->sp = tsp;
+ if (tsp->pvNode)
+ search<PV, true>(pos, ss, tsp->alpha, tsp->beta, tsp->depth, tsp->ply);
+ else {
+ search<NonPV, true>(pos, ss, tsp->alpha, tsp->beta, tsp->depth, tsp->ply);
+ }
assert(threads[threadID].state == THREAD_SEARCHING);
threads[threadID].state = THREAD_AVAILABLE;
lock_grab(&(sp->lock));
lock_release(&(sp->lock));
+ // 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(threads[threadID].state == THREAD_AVAILABLE);
threads[threadID].state = THREAD_SEARCHING;
volatile int i;
bool ok;
-#if !defined(_MSC_VER)
- pthread_t pthread[1];
-#endif
-
// Initialize global locks
lock_init(&MPLock);
- lock_init(&WaitLock);
-#if !defined(_MSC_VER)
- pthread_cond_init(&WaitCond, NULL);
-#else
for (i = 0; i < MAX_THREADS; i++)
- SitIdleEvent[i] = CreateEvent(0, FALSE, FALSE, 0);
-#endif
+ cond_init(&WaitCond[i]);
// Initialize splitPoints[] locks
for (i = 0; i < MAX_THREADS; i++)
// Will be set just before program exits to properly end the threads
AllThreadsShouldExit = false;
- // Threads will be put to sleep as soon as created
- AllThreadsShouldSleep = true;
-
- // All threads except the main thread should be initialized to THREAD_AVAILABLE
+ // Threads will be put all threads to sleep as soon as created
ActiveThreads = 1;
+
+ // All threads except the main thread should be initialized to THREAD_INITIALIZING
threads[0].state = THREAD_SEARCHING;
for (i = 1; i < MAX_THREADS; i++)
- threads[i].state = THREAD_AVAILABLE;
+ threads[i].state = THREAD_INITIALIZING;
// Launch the helper threads
for (i = 1; i < MAX_THREADS; i++)
{
#if !defined(_MSC_VER)
+ pthread_t pthread[1];
ok = (pthread_create(pthread, NULL, init_thread, (void*)(&i)) == 0);
#else
ok = (CreateThread(NULL, 0, init_thread, (LPVOID)(&i), 0, NULL) != NULL);
}
// Wait until the thread has finished launching and is gone to sleep
- while (threads[i].state != THREAD_SLEEPING) {}
+ while (threads[i].state == THREAD_INITIALIZING) {}
}
}
void ThreadsManager::exit_threads() {
- ActiveThreads = MAX_THREADS; // HACK
- AllThreadsShouldSleep = true; // HACK
- wake_sleeping_threads();
-
- // This makes the threads to exit idle_loop()
- AllThreadsShouldExit = true;
+ AllThreadsShouldExit = true; // Let the woken up threads to exit idle_loop()
- // Wait for thread termination
+ // Wake up all the threads and waits for termination
for (int i = 1; i < MAX_THREADS; i++)
+ {
+ wake_sleeping_thread(i);
while (threads[i].state != THREAD_TERMINATED) {}
+ }
// Now we can safely destroy the locks
for (int i = 0; i < MAX_THREADS; i++)
for (int j = 0; j < MAX_ACTIVE_SPLIT_POINTS; j++)
lock_destroy(&(threads[i].splitPoints[j].lock));
- lock_destroy(&WaitLock);
lock_destroy(&MPLock);
+
+ // Now we can safely destroy the wait conditions
+ for (int i = 0; i < MAX_THREADS; i++)
+ cond_destroy(&WaitCond[i]);
}
assert(threadID >= 0 && threadID < ActiveThreads);
- SplitPoint* sp;
+ SplitPoint* sp = threads[threadID].splitPoint;
- for (sp = threads[threadID].splitPoint; sp && !sp->stopRequest; sp = sp->parent) {}
+ for ( ; sp && !sp->stopRequest; sp = sp->parent) {}
return sp != NULL;
}
// Make a local copy to be sure doesn't change under our feet
int localActiveSplitPoints = threads[slave].activeSplitPoints;
- if (localActiveSplitPoints == 0)
- // No active split points means that the thread is available as
- // a slave for any other thread.
- return true;
-
- if (ActiveThreads == 2)
+ // No active split points means that the thread is available as
+ // a slave for any other thread.
+ if (localActiveSplitPoints == 0 || ActiveThreads == 2)
return true;
// Apply the "helpful master" concept if possible. Use localActiveSplitPoints
// 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 sp_search(). When all threads have returned from sp_search() then
- // split() returns.
+ // 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>
void ThreadsManager::split(const Position& p, SearchStack* ss, int ply, Value* alpha,
const Value beta, Value* bestValue, Depth depth, Move threatMove,
- bool mateThreat, int* moveCount, MovePicker* mp, bool pvNode) {
+ bool mateThreat, int moveCount, MovePicker* mp, bool pvNode) {
assert(p.is_ok());
assert(ply > 0 && ply < PLY_MAX);
assert(*bestValue >= -VALUE_INFINITE);
splitPoint.pvNode = pvNode;
splitPoint.bestValue = *bestValue;
splitPoint.mp = mp;
- splitPoint.moveCount = *moveCount;
+ splitPoint.moveCount = moveCount;
splitPoint.pos = &p;
splitPoint.parentSstack = ss;
for (i = 0; i < ActiveThreads; i++)
assert(i == master || threads[i].state == THREAD_BOOKED);
threads[i].state = THREAD_WORKISWAITING; // This makes the slave to exit from idle_loop()
+ if (i != master)
+ wake_sleeping_thread(i);
}
// Everything is set up. The master thread enters the idle loop, from
}
- // wake_sleeping_threads() wakes up all sleeping threads when it is time
+ // wake_sleeping_thread() wakes up all sleeping threads when it is time
// to start a new search from the root.
- void ThreadsManager::wake_sleeping_threads() {
-
- assert(AllThreadsShouldSleep);
- assert(ActiveThreads > 0);
-
- AllThreadsShouldSleep = false;
-
- if (ActiveThreads == 1)
- return;
-
-#if !defined(_MSC_VER)
- pthread_mutex_lock(&WaitLock);
- pthread_cond_broadcast(&WaitCond);
- pthread_mutex_unlock(&WaitLock);
-#else
- for (int i = 1; i < MAX_THREADS; i++)
- SetEvent(SitIdleEvent[i]);
-#endif
+ void ThreadsManager::wake_sleeping_thread(int threadID) {
+ lock_grab(&MPLock);
+ cond_signal(&WaitCond[threadID]);
+ lock_release(&MPLock);
}
- // put_threads_to_sleep() makes all the threads go to sleep just before
- // to leave think(), at the end of the search. Threads should have already
- // finished the job and should be idle.
-
- void ThreadsManager::put_threads_to_sleep() {
-
- assert(!AllThreadsShouldSleep);
-
- // This makes the threads to go to sleep
- AllThreadsShouldSleep = true;
- }
-
/// The RootMoveList class
// RootMoveList c'tor
projects / stockfish / blobdiff