typedef std::vector<RootMove> Base;
void init(Position& pos, Move searchMoves[]);
- void set_non_pv_scores(const Position& pos, Move ttm, SearchStack* ss);
-
void sort() { insertion_sort<RootMove, Base::iterator>(begin(), end()); }
void sort_multipv(int n) { insertion_sort<RootMove, Base::iterator>(begin(), begin() + n); }
// A dispatcher to choose among different move sources according to the type of node
template<bool SpNode, bool Root> struct MovePickerExt;
- // In Root nodes use RootMoveList Rml as source
- template<> struct MovePickerExt<false, true> {
+ // In Root nodes use RootMoveList Rml as source. Score and sort the moves before to search them.
+ template<> struct MovePickerExt<false, true> : private MovePicker {
+
+ MovePickerExt(const Position& p, Move, Depth, const History& h, SearchStack* ss, Value beta)
+ : MovePicker(p, Rml[0].pv[0], ONE_PLY, h, ss, beta), firstCall(true) { // FIXME use depth
- MovePickerExt(const Position&, Move, Depth, const History&, SearchStack*, Value)
- : rm(Rml.begin()), firstCall(true) {}
+ Move move;
+ Value score = VALUE_ZERO;
+
+ // Score root moves using the standard way used in main search, the moves
+ // are scored according to the order in which are returned by MovePicker.
+ // This is the second order score that is used to compare the moves when
+ // the first order pv scores of both moves are equal.
+ while ((move = MovePicker::get_next_move()) != MOVE_NONE)
+ for (rm = Rml.begin(); rm != Rml.end(); ++rm)
+ if (rm->pv[0] == move)
+ {
+ rm->non_pv_score = score--;
+ break;
+ }
+
+ Rml.sort();
+ rm = Rml.begin();
+ }
Move get_next_move() {
Move id_loop(Position& pos, Move searchMoves[], Move* ponderMove) {
SearchStack ss[PLY_MAX_PLUS_2];
-
- Depth depth;
- Move EasyMove = MOVE_NONE;
- Value value, alpha = -VALUE_INFINITE, beta = VALUE_INFINITE;
- int researchCountFL, researchCountFH;
-
- int iteration;
+ Value bestValues[PLY_MAX_PLUS_2];
int bestMoveChanges[PLY_MAX_PLUS_2];
- Value values[PLY_MAX_PLUS_2];
- int aspirationDelta = 0;
+ int iteration, researchCountFL, researchCountFH, aspirationDelta;
+ Value value, alpha, beta;
+ Depth depth;
+ Move EasyMove;
// Moves to search are verified, scored and sorted
Rml.init(pos, searchMoves);
+ // Initialize FIXME move before Rml.init()
+ TT.new_search();
+ H.clear();
+ init_ss_array(ss, PLY_MAX_PLUS_2);
+ alpha = -VALUE_INFINITE, beta = VALUE_INFINITE;
+ EasyMove = MOVE_NONE;
+ aspirationDelta = 0;
+ iteration = 1;
+
// Handle special case of searching on a mate/stale position
if (Rml.size() == 0)
{
- Value s = (pos.is_check() ? -VALUE_MATE : VALUE_DRAW);
-
- cout << "info depth " << 1
- << " score " << value_to_uci(s) << endl;
+ cout << "info depth " << iteration << " score "
+ << value_to_uci(pos.is_check() ? -VALUE_MATE : VALUE_DRAW)
+ << endl;
return MOVE_NONE;
}
- // Initialize
- TT.new_search();
- H.clear();
- init_ss_array(ss, PLY_MAX_PLUS_2);
- values[1] = Rml[0].pv_score;
- iteration = 1;
-
- // Send initial RootMoveList scoring (iteration 1)
+ // Send initial scoring (iteration 1)
cout << set960(pos.is_chess960()) // Is enough to set once at the beginning
<< "info depth " << iteration
<< "\n" << Rml[0].pv_info_to_uci(pos, ONE_PLY, alpha, beta) << endl;
EasyMove = Rml[0].pv[0];
// Iterative deepening loop
- while (iteration < PLY_MAX)
+ while (++iteration <= PLY_MAX && (!MaxDepth || iteration <= MaxDepth) && !StopRequest)
{
- // Initialize iteration
- iteration++;
- Rml.bestMoveChanges = 0;
-
cout << "info depth " << iteration << endl;
+ Rml.bestMoveChanges = researchCountFL = researchCountFH = 0;
+ depth = (iteration - 2) * ONE_PLY + InitialDepth;
+
// Calculate dynamic aspiration window based on previous iterations
- if (MultiPV == 1 && iteration >= 6 && abs(values[iteration - 1]) < VALUE_KNOWN_WIN)
+ if (MultiPV == 1 && iteration >= 6 && abs(bestValues[iteration - 1]) < VALUE_KNOWN_WIN)
{
- int prevDelta1 = values[iteration - 1] - values[iteration - 2];
- int prevDelta2 = values[iteration - 2] - values[iteration - 3];
+ int prevDelta1 = bestValues[iteration - 1] - bestValues[iteration - 2];
+ int prevDelta2 = bestValues[iteration - 2] - bestValues[iteration - 3];
aspirationDelta = Max(abs(prevDelta1) + abs(prevDelta2) / 2, 16);
aspirationDelta = (aspirationDelta + 7) / 8 * 8; // Round to match grainSize
- alpha = Max(values[iteration - 1] - aspirationDelta, -VALUE_INFINITE);
- beta = Min(values[iteration - 1] + aspirationDelta, VALUE_INFINITE);
+ alpha = Max(bestValues[iteration - 1] - aspirationDelta, -VALUE_INFINITE);
+ beta = Min(bestValues[iteration - 1] + aspirationDelta, VALUE_INFINITE);
}
- depth = (iteration - 2) * ONE_PLY + InitialDepth;
-
- researchCountFL = researchCountFH = 0;
-
// We start with small aspiration window and in case of fail high/low, we
// research with bigger window until we are not failing high/low anymore.
while (true)
{
- // Sort the moves before to (re)search
- Rml.set_non_pv_scores(pos, Rml[0].pv[0], ss);
- Rml.sort();
-
// Search to the current depth
value = search<PV, false, true>(pos, ss, alpha, beta, depth, 0);
- // Sort the moves and write PV lines to transposition table, in case
+ // Sort root moves and write PV lines to transposition table, in case
// the relevant entries have been overwritten during the search.
Rml.sort();
for (int i = 0; i < Min(MultiPV, (int)Rml.size()); i++)
Rml[i].insert_pv_in_tt(pos);
- bestMoveChanges[iteration] = Rml.bestMoveChanges;
-
+ // Value cannot be trusted. Break out immediately!
if (StopRequest)
- break;
+ break; // FIXME move to 'while' condition
assert(value >= alpha);
+ bestMoveChanges[iteration] = Rml.bestMoveChanges; // FIXME move outside fail high/low loop
+
+ // In case of failing high/low increase aspiration window and research,
+ // otherwise exit the fail high/low loop.
if (value >= beta)
{
- // Prepare for a research after a fail high, each time with a wider window
beta = Min(beta + aspirationDelta * (1 << researchCountFH), VALUE_INFINITE);
researchCountFH++;
}
AspirationFailLow = true;
StopOnPonderhit = false;
- // Prepare for a research after a fail low, each time with a wider window
alpha = Max(alpha - aspirationDelta * (1 << researchCountFL), -VALUE_INFINITE);
researchCountFL++;
}
break;
}
- if (StopRequest)
- break; // Value cannot be trusted. Break out immediately!
-
//Save info about search result
- values[iteration] = value;
+ bestValues[iteration] = value;
// Drop the easy move if differs from the new best move
if (Rml[0].pv[0] != EasyMove)
EasyMove = MOVE_NONE;
- if (UseTimeManagement)
+ if (UseTimeManagement && !StopRequest)
{
// Time to stop?
bool noMoreTime = false;
// Stop search early when the last two iterations returned a mate score
if ( iteration >= 6
- && abs(values[iteration]) >= abs(VALUE_MATE) - 100
- && abs(values[iteration-1]) >= abs(VALUE_MATE) - 100)
+ && abs(bestValues[iteration]) >= abs(VALUE_MATE) - 100
+ && abs(bestValues[iteration-1]) >= abs(VALUE_MATE) - 100)
noMoreTime = true;
// Stop search early if one move seems to be much better than the others
break;
}
}
-
- if (MaxDepth && iteration >= MaxDepth)
- break;
}
*ponderMove = Rml[0].pv[1];
mateThreat = sp->mateThreat;
goto split_point_start;
}
- else {} // Hack to fix icc's "statement is unreachable" warning
+ else if (Root)
+ bestValue = alpha;
// Step 1. Initialize node and poll. Polling can abort search
ss->currentMove = ss->bestMove = threatMove = MOVE_NONE;
(ss+2)->killers[0] = (ss+2)->killers[1] = (ss+2)->mateKiller = MOVE_NONE;
- if (!Root)
+ if (!Root) // FIXME remove
{
if (threadID == 0 && ++NodesSincePoll > NodesBetweenPolls)
{
&& !excludedMove // Do not allow recursive singular extension search
&& (tte->type() & VALUE_TYPE_LOWER)
&& tte->depth() >= depth - 3 * ONE_PLY;
- if (Root)
- bestValue = alpha;
-
if (SpNode)
{
lock_grab(&(sp->lock));
if (Root)
{
+ // To avoid to exit with bestValue == -VALUE_INFINITE
+ if (value > bestValue)
+ bestValue = value;
+
// Finished searching the move. If StopRequest is true, the search
// was aborted because the user interrupted the search or because we
// ran out of time. In this case, the return value of the search cannot
for (int j = 0; j < Min(MultiPV, (int)Rml.size()); j++)
cout << Rml[j].pv_info_to_uci(pos, depth, alpha, beta, j) << endl;
- // Update alpha. In multi-pv we don't use aspiration window
- if (MultiPV == 1)
- {
- // Raise alpha to setup proper non-pv search upper bound
- if (value > alpha)
- alpha = bestValue = value;
- }
- else // Set alpha equal to minimum score among the PV lines
- alpha = bestValue = Rml[Min(moveCount, MultiPV) - 1].pv_score; // FIXME why moveCount?
+ // Update alpha. In multi-pv we don't use aspiration window, so
+ // set alpha equal to minimum score among the PV lines.
+ if (MultiPV > 1)
+ alpha = Rml[Min(moveCount, MultiPV) - 1].pv_score; // FIXME why moveCount?
+ else if (value > alpha)
+ alpha = value;
} // PV move or new best move
}
sort();
}
- // Score root moves using the standard way used in main search, the moves
- // are scored according to the order in which are returned by MovePicker.
- // This is the second order score that is used to compare the moves when
- // the first order pv scores of both moves are equal.
-
- void RootMoveList::set_non_pv_scores(const Position& pos, Move ttm, SearchStack* ss)
- {
- Move move;
- Value score = VALUE_ZERO;
- MovePicker mp(pos, ttm, ONE_PLY, H, ss);
-
- while ((move = mp.get_next_move()) != MOVE_NONE)
- for (Base::iterator it = begin(); it != end(); ++it)
- if (it->pv[0] == move)
- {
- it->non_pv_score = score--;
- break;
- }
- }
-
} // namespace
projects / stockfish / blobdiff