Do not pass discovery check candidates in Position::do_move()

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index f7f62b2344e7c5d2837fd21698d3b222a274771a..e621d702dc42edd456cf80513ad879f3209efc55 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -267,7 +267,7 @@ namespace {
   bool connected_moves(const Position &pos, Move m1, Move m2);
   bool value_is_mate(Value value);
   bool move_is_killer(Move m, const SearchStack& ss);
-  Depth extension(const Position &pos, Move m, bool pvNode, bool check, bool singleReply, bool mateThreat, bool* dangerous);
+  Depth extension(const Position &pos, Move m, bool pvNode, bool capture, bool check, bool singleReply, bool mateThreat, bool* dangerous);
   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);
@@ -805,11 +805,11 @@ namespace {
 
         // Decide search depth for this move
         bool dangerous;
-        ext = extension(pos, move, true, pos.move_is_check(move), false, false, &dangerous);
+        ext = extension(pos, move, true, pos.move_is_capture(move), pos.move_is_check(move), false, false, &dangerous);
         newDepth = (Iteration - 2) * OnePly + ext + InitialDepth;
 
         // Make the move, and search it
-        pos.do_move(move, u, dcCandidates);
+        pos.do_move(move, u);
 
         if (i < MultiPV)
         {
@@ -983,9 +983,10 @@ namespace {
     Move move, movesSearched[256];
     int moveCount = 0;
     Value value, bestValue = -VALUE_INFINITE;
-    Bitboard dcCandidates = mp.discovered_check_candidates();
+    Color us = pos.side_to_move();
+    Bitboard dcCandidates = pos.discovered_check_candidates(us);
     bool isCheck = pos.is_check();
-    bool mateThreat = pos.has_mate_threat(opposite_color(pos.side_to_move()));
+    bool mateThreat = pos.has_mate_threat(opposite_color(us));
 
     // Loop through all legal moves until no moves remain or a beta cutoff
     // occurs.
@@ -996,7 +997,7 @@ namespace {
       assert(move_is_ok(move));
 
       bool singleReply = (isCheck && mp.number_of_moves() == 1);
-      bool moveIsCheck = pos.move_is_check(move, dcCandidates);
+      bool moveIsCheck = pos.move_is_check(move);
       bool moveIsCapture = pos.move_is_capture(move);
 
       movesSearched[moveCount++] = ss[ply].currentMove = move;
@@ -1009,12 +1010,12 @@ namespace {
 
       // Decide the new search depth
       bool dangerous;
-      Depth ext = extension(pos, move, true, moveIsCheck, singleReply, mateThreat, &dangerous);
+      Depth ext = extension(pos, move, true, moveIsCapture, moveIsCheck, singleReply, mateThreat, &dangerous);
       Depth newDepth = depth - OnePly + ext;
 
       // Make and search the move
       UndoInfo u;
-      pos.do_move(move, u, dcCandidates);
+      pos.do_move(move, u);
 
       if (moveCount == 1) // The first move in list is the PV
           value = -search_pv(pos, ss, -beta, -alpha, newDepth, ply+1, threadID);
@@ -1247,8 +1248,8 @@ namespace {
     {
         Value v = qsearch(pos, ss, beta-1, beta, Depth(0), ply, threadID);
         if (   (v < beta - RazorMargin - RazorMargin / 4)
-            || (depth <= 2*OnePly && v < beta - RazorMargin)
-            || (depth <=   OnePly && v < beta - RazorMargin / 2))
+            || (depth < 3*OnePly && v < beta - RazorMargin)
+            || (depth < 2*OnePly && v < beta - RazorMargin / 2))
             return v;
     }
 
@@ -1283,7 +1284,7 @@ namespace {
     Move move, movesSearched[256];
     int moveCount = 0;
     Value value, bestValue = -VALUE_INFINITE;
-    Bitboard dcCandidates = mp.discovered_check_candidates();
+    Bitboard dcCandidates = pos.discovered_check_candidates(pos.side_to_move());
     Value futilityValue = VALUE_NONE;
     bool useFutilityPruning =   UseFutilityPruning
                              && depth < SelectiveDepth
@@ -1298,14 +1299,14 @@ namespace {
       assert(move_is_ok(move));
 
       bool singleReply = (isCheck && mp.number_of_moves() == 1);
-      bool moveIsCheck = pos.move_is_check(move, dcCandidates);
+      bool moveIsCheck = pos.move_is_check(move);
       bool moveIsCapture = pos.move_is_capture(move);
 
       movesSearched[moveCount++] = ss[ply].currentMove = move;
 
       // Decide the new search depth
       bool dangerous;
-      Depth ext = extension(pos, move, false, moveIsCheck, singleReply, mateThreat, &dangerous);
+      Depth ext = extension(pos, move, false, moveIsCapture, moveIsCheck, singleReply, mateThreat, &dangerous);
       Depth newDepth = depth - OnePly + ext;
 
       // Futility pruning
@@ -1338,7 +1339,7 @@ namespace {
 
       // Make and search the move
       UndoInfo u;
-      pos.do_move(move, u, dcCandidates);
+      pos.do_move(move, u);
 
       // 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.
@@ -1470,8 +1471,9 @@ namespace {
     MovePicker mp = MovePicker(pos, pvNode, MOVE_NONE, EmptySearchStack, depth, isCheck ? NULL : &ei);
     Move move;
     int moveCount = 0;
-    Bitboard dcCandidates = mp.discovered_check_candidates();
-    bool enoughMaterial = pos.non_pawn_material(pos.side_to_move()) > RookValueMidgame;
+    Color us = pos.side_to_move();
+    Bitboard dcCandidates = pos.discovered_check_candidates(us);
+    bool enoughMaterial = pos.non_pawn_material(us) > RookValueMidgame;
 
     // Loop through the moves until no moves remain or a beta cutoff
     // occurs.
@@ -1489,7 +1491,7 @@ namespace {
           && !isCheck
           && !pvNode
           && !move_promotion(move)
-          && !pos.move_is_check(move, dcCandidates)
+          && !pos.move_is_check(move)
           && !pos.move_is_passed_pawn_push(move))
       {
           Value futilityValue = staticValue
@@ -1517,7 +1519,7 @@ namespace {
 
       // Make and search the move.
       UndoInfo u;
-      pos.do_move(move, u, dcCandidates);
+      pos.do_move(move, u);
       Value value = -qsearch(pos, ss, -beta, -alpha, depth-OnePly, ply+1, threadID);
       pos.undo_move(move, u);
 
@@ -1583,8 +1585,9 @@ namespace {
            && (move = sp->mp->get_next_move(sp->lock)) != MOVE_NONE)
     {
       assert(move_is_ok(move));
+      assert(pos.discovered_check_candidates(pos.side_to_move()) == sp->dcCandidates);
 
-      bool moveIsCheck = pos.move_is_check(move, sp->dcCandidates);
+      bool moveIsCheck = pos.move_is_check(move);
       bool moveIsCapture = pos.move_is_capture(move);
 
       lock_grab(&(sp->lock));
@@ -1595,7 +1598,7 @@ namespace {
 
       // Decide the new search depth.
       bool dangerous;
-      Depth ext = extension(pos, move, false, moveIsCheck, false, false, &dangerous);
+      Depth ext = extension(pos, move, false, moveIsCapture, moveIsCheck, false, false, &dangerous);
       Depth newDepth = sp->depth - OnePly + ext;
 
       // Prune?
@@ -1609,7 +1612,7 @@ namespace {
 
       // Make and search the move.
       UndoInfo u;
-      pos.do_move(move, u, sp->dcCandidates);
+      pos.do_move(move, u);
 
       // 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.
@@ -1694,7 +1697,9 @@ namespace {
            && !thread_should_stop(threadID)
            && (move = sp->mp->get_next_move(sp->lock)) != MOVE_NONE)
     {
-      bool moveIsCheck = pos.move_is_check(move, sp->dcCandidates);
+      assert(pos.discovered_check_candidates(pos.side_to_move()) == sp->dcCandidates);
+
+      bool moveIsCheck = pos.move_is_check(move);
       bool moveIsCapture = pos.move_is_capture(move);
 
       assert(move_is_ok(move));
@@ -1713,12 +1718,12 @@ namespace {
 
       // Decide the new search depth.
       bool dangerous;
-      Depth ext = extension(pos, move, true, moveIsCheck, false, false, &dangerous);
+      Depth ext = extension(pos, move, true, moveIsCapture, moveIsCheck, false, false, &dangerous);
       Depth newDepth = sp->depth - OnePly + ext;
 
       // Make and search the move.
       UndoInfo u;
-      pos.do_move(move, u, sp->dcCandidates);
+      pos.do_move(move, u);
 
       // 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.
@@ -2113,7 +2118,7 @@ namespace {
 
     // Case 4: The destination square for m2 is attacked by the moving piece
     // in m1:
-    if(pos.piece_attacks_square(t1, t2))
+    if(pos.piece_attacks_square(pos.piece_on(t1), t1, t2))
       return true;
 
     // Case 5: Discovered check, checking piece is the piece moved in m1:
@@ -2178,7 +2183,7 @@ namespace {
   // extended, as example because the corresponding UCI option is set to zero,
   // the move is marked as 'dangerous' so, at least, we avoid to prune it.
 
-  Depth extension(const Position &pos, Move m, bool pvNode, bool check,
+  Depth extension(const Position& pos, Move m, bool pvNode, bool capture, bool check,
                   bool singleReply, bool mateThreat, bool* dangerous) {
 
     assert(m != MOVE_NONE);
@@ -2209,7 +2214,7 @@ namespace {
         }
     }
 
-    if (   pos.move_is_capture(m)
+    if (   capture
         && pos.type_of_piece_on(move_to(m)) != PAWN
         && (  pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK)
             - pos.midgame_value_of_piece_on(move_to(m)) == Value(0))
@@ -2221,7 +2226,7 @@ namespace {
     }
 
     if (   pvNode
-        && pos.move_is_capture(m)
+        && capture
         && pos.type_of_piece_on(move_to(m)) != PAWN
         && pos.see(m) >= 0)
     {