void sp_update_pv(SearchStack *pss, SearchStack ss[], int ply);
bool connected_moves(const Position &pos, Move m1, Move m2);
bool move_is_killer(Move m, const SearchStack& ss);
- Depth extension(const Position &pos, Move m, bool pvNode, bool check, bool singleReply, bool mateThreat);
+ Depth extension(const Position &pos, Move m, bool pvNode, bool check, bool singleReply, bool mateThreat, bool* extendable);
bool ok_to_do_nullmove(const Position &pos);
bool ok_to_prune(const Position &pos, Move m, Move threat, Depth d);
bool ok_to_use_TT(const TTEntry* tte, Depth depth, Value beta, int ply);
<< " currmovenumber " << i + 1 << std::endl;
// Decide search depth for this move
- ext = extension(pos, move, true, pos.move_is_check(move), false, false);
+ bool dummy;
+ ext = extension(pos, move, true, pos.move_is_check(move), false, false, &dummy);
newDepth = (Iteration - 2) * OnePly + ext + InitialDepth;
// Make the move, and search it
ss[ply].currentMoveCaptureValue = Value(0);
// Decide the new search depth
- Depth ext = extension(pos, move, true, moveIsCheck, singleReply, mateThreat);
+ bool extendable;
+ Depth ext = extension(pos, move, true, moveIsCheck, singleReply, mateThreat, &extendable);
Depth newDepth = depth - OnePly + ext;
// Make and search the move
// Try to reduce non-pv search depth by one ply if move seems not problematic,
// if the move fails high will be re-searched at full depth.
if ( depth >= 2*OnePly
- && ext == Depth(0)
+ && !extendable
&& moveCount >= LMRPVMoves
&& !moveIsCapture
&& !move_promotion(move)
movesSearched[moveCount++] = ss[ply].currentMove = move;
// Decide the new search depth
- Depth ext = extension(pos, move, false, moveIsCheck, singleReply, mateThreat);
+ bool extendable;
+ Depth ext = extension(pos, move, false, moveIsCheck, singleReply, mateThreat, &extendable);
Depth newDepth = depth - OnePly + ext;
// Futility pruning
if ( useFutilityPruning
- && ext == Depth(0)
+ && !extendable
&& !moveIsCapture
&& !moveIsPassedPawnPush
&& !move_promotion(move))
// Try to reduce non-pv search depth by one ply if move seems not problematic,
// if the move fails high will be re-searched at full depth.
if ( depth >= 2*OnePly
- && ext == Depth(0)
+ && !extendable
&& moveCount >= LMRNonPVMoves
&& !moveIsCapture
&& !move_promotion(move)
ss[sp->ply].currentMove = move;
// Decide the new search depth.
- Depth ext = extension(pos, move, false, moveIsCheck, false, false);
+ bool extendable;
+ Depth ext = extension(pos, move, false, moveIsCheck, false, false, &extendable);
Depth newDepth = sp->depth - OnePly + ext;
// Prune?
if ( useFutilityPruning
- && ext == Depth(0)
+ && !extendable
&& !moveIsCapture
&& !moveIsPassedPawnPush
&& !move_promotion(move)
// Try to reduce non-pv search depth by one ply if move seems not problematic,
// if the move fails high will be re-searched at full depth.
- if ( ext == Depth(0)
+ if ( !extendable
&& moveCount >= LMRNonPVMoves
&& !moveIsCapture
&& !moveIsPassedPawnPush
ss[sp->ply].currentMove = move;
// Decide the new search depth.
- Depth ext = extension(pos, move, true, moveIsCheck, false, false);
+ bool extendable;
+ Depth ext = extension(pos, move, true, moveIsCheck, false, false, &extendable);
Depth newDepth = sp->depth - OnePly + ext;
// Make and search the move.
// Try to reduce non-pv search depth by one ply if move seems not problematic,
// if the move fails high will be re-searched at full depth.
- if ( ext == Depth(0)
+ if ( !extendable
&& moveCount >= LMRPVMoves
&& !moveIsCapture
&& !moveIsPassedPawnPush
NodesSincePoll = 0;
}
}
-
ss[ply].pv[ply] = ss[ply].pv[ply+1] = ss[ply].currentMove = MOVE_NONE;
ss[ply+2].mateKiller = MOVE_NONE;
ss[ply].threatMove = MOVE_NONE;
// particular) are searched with bigger depth than ordinary moves.
Depth extension(const Position &pos, Move m, bool pvNode,
- bool check, bool singleReply, bool mateThreat) {
+ bool check, bool singleReply, bool mateThreat, bool* extendable) {
Depth result = Depth(0);
+ *extendable = check || singleReply || mateThreat;
if (check)
result += CheckExtension[pvNode];
if (singleReply)
result += SingleReplyExtension[pvNode];
+ if (mateThreat)
+ result += MateThreatExtension[pvNode];
+
if (pos.move_is_pawn_push_to_7th(m))
+ {
result += PawnPushTo7thExtension[pvNode];
-
+ *extendable = true;
+ }
if (pos.move_is_passed_pawn_push(m))
+ {
result += PassedPawnExtension[pvNode];
-
- if (mateThreat)
- result += MateThreatExtension[pvNode];
+ *extendable = true;
+ }
if ( pos.midgame_value_of_piece_on(move_to(m)) >= RookValueMidgame
&& ( pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK)
- pos.midgame_value_of_piece_on(move_to(m)) == Value(0))
&& !move_promotion(m))
+ {
result += PawnEndgameExtension[pvNode];
+ *extendable = true;
+ }
if ( pvNode
&& pos.move_is_capture(m)
&& pos.type_of_piece_on(move_to(m)) != PAWN
&& pos.see(m) >= 0)
+ {
result += OnePly/2;
+ *extendable = true;
+ }
return Min(result, OnePly);
}