No functional change.
const Score QueenOnPawnBonus = make_score( 4, 20);
const Score RookOpenFileBonus = make_score(43, 21);
const Score RookHalfOpenFileBonus = make_score(19, 10);
- const Score BishopPawnsPenalty = make_score(8, 12);
+ const Score BishopPawnsPenalty = make_score( 8, 12);
const Score UndefendedMinorPenalty = make_score(25, 10);
- const Score TrappedRookPenalty = make_score(90, 0);
+ const Score TrappedRookPenalty = make_score(90, 0);
// Penalty for a bishop on a1/h1 (a8/h8 for black) which is trapped by
// a friendly pawn on b2/g2 (b7/g7 for black). This can obviously only
/// search captures, promotions and some checks) and about how important good
/// move ordering is at the current node.
-MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const History& h,
- Search::Stack* s, Move refutationMove, Value beta) : pos(p), Hist(h), depth(d) {
+MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const History& h, const Refutations& r,
+ Search::Stack* s, Value beta) : pos(p), Hist(h), depth(d) {
assert(d > DEPTH_ZERO);
killers[0].move = ss->killers[0];
killers[1].move = ss->killers[1];
- killers[2].move = refutationMove;
+ Square prevSq = to_sq((ss-1)->currentMove);
+ killers[2].move = r[pos.piece_on(prevSq)][prevSq];
// Consider sligtly negative captures as good if at low depth and far from beta
if (ss && ss->staticEval < beta - PawnValueMg && d < 3 * ONE_PLY)
/// The Stats struct stores moves statistics. According to the template parameter
-/// the class can store both History and Gains type statistics. History records
+/// the class can store History, Gains and Refutations statistics. History records
/// how often different moves have been successful or unsuccessful during the
/// current search and is used for reduction and move ordering decisions. Gains
/// records the move's best evaluation gain from one ply to the next and is used
-/// for pruning decisions. Entries are stored according only to moving piece and
-/// destination square, in particular two moves with different origin but same
-/// destination and same piece will be considered identical.
-template<bool Gain>
+/// for pruning decisions. Refutations store the move that refute a previous one.
+/// Entries are stored according only to moving piece and destination square, in
+/// particular two moves with different origin but same destination and same piece
+/// will be considered identical.
+template<bool Gain, typename T>
struct Stats {
static const Value Max = Value(2000);
- const Value* operator[](Piece p) const { return &table[p][0]; }
+ const T* operator[](Piece p) const { return &table[p][0]; }
void clear() { memset(table, 0, sizeof(table)); }
+ void update(Piece p, Square to, Move m) { table[p][to] = m; }
void update(Piece p, Square to, Value v) {
if (Gain)
}
private:
- Value table[PIECE_NB][SQUARE_NB];
+ T table[PIECE_NB][SQUARE_NB];
};
-typedef Stats<false> History;
-typedef Stats<true> Gains;
-
-// FIXME: Document me
-struct RefutationTable {
-
- void clear() { memset(table, 0, sizeof(table)); }
- void update(Piece p, Square to, Move m) { table[p][to] = m; }
- Move get(Piece p, Square to) const { return table[p][to]; }
-
-private:
- Move table[PIECE_NB][SQUARE_NB]; // Mapping: "move A" -> "move B which refutes move A"
+typedef Stats<true, Value> Gains;
+typedef Stats<false, Value> History;
+typedef Stats<false, Move> Refutations;
-};
/// MovePicker class is used to pick one pseudo legal move at a time from the
/// current position. The most important method is next_move(), which returns a
MovePicker& operator=(const MovePicker&); // Silence a warning under MSVC
public:
- MovePicker(const Position&, Move, Depth, const History&, Search::Stack*, Move, Value);
+ MovePicker(const Position&, Move, Depth, const History&, const Refutations&, Search::Stack*, Value);
MovePicker(const Position&, Move, Depth, const History&, Square);
MovePicker(const Position&, Move, const History&, PieceType);
template<bool SpNode> Move next_move();
Value DrawValue[COLOR_NB];
History Hist;
Gains Gain;
- RefutationTable Refutation;
+ Refutations Refutation;
template <NodeType NT>
Value search(Position& pos, Stack* ss, Value alpha, Value beta, Depth depth);
split_point_start: // At split points actual search starts from here
- Move prevMove = (ss-1)->currentMove;
- Square prevSq = to_sq(prevMove);
- Piece prevP = pos.piece_on(prevSq);
- Move refutationMove = Refutation.get(prevP, prevSq);
-
- MovePicker mp(pos, ttMove, depth, Hist, ss, refutationMove, PvNode ? -VALUE_INFINITE : beta);
+ MovePicker mp(pos, ttMove, depth, Hist, Refutation, ss, PvNode ? -VALUE_INFINITE : beta);
CheckInfo ci(pos);
value = bestValue; // Workaround a bogus 'uninitialized' warning under gcc
singularExtensionNode = !RootNode
// Increase history value of the cut-off move
Value bonus = Value(int(depth) * int(depth));
Hist.update(pos.piece_moved(bestMove), to_sq(bestMove), bonus);
- Refutation.update(prevP, prevSq, bestMove);
+ Square prevSq = to_sq((ss-1)->currentMove);
+ Refutation.update(pos.piece_on(prevSq), prevSq, bestMove);
// Decrease history of all the other played non-capture moves
for (int i = 0; i < playedMoveCount - 1; i++)