MovePicker: avoid calling see() for LxH and equal captures

[stockfish] / src / movepick.cpp

diff --git a/src/movepick.cpp b/src/movepick.cpp
index 02116b1cbfaf4f177adad36c6e7620e066578294..95bbddba670788af7d2b937a72ddb4c28a791a31 100644 (file)
--- a/src/movepick.cpp
+++ b/src/movepick.cpp
@@ -66,23 +66,26 @@ namespace {
 /// move ordering is at the current node.
 
 MovePicker::MovePicker(const Position& p, bool pv, Move ttm,
-                       Move mk, Move k1, Move k2, Depth d, EvalInfo* ei) : pos(p) {
+                       const SearchStack& ss, Depth d, EvalInfo* ei) : pos(p) {
   pvNode = pv;
   ttMove = ttm;
-  mateKiller = (mk == ttm)? MOVE_NONE : mk;
-  killer1 = k1;
-  killer2 = k2;
+  mateKiller = (ss.mateKiller == ttm)? MOVE_NONE : ss.mateKiller;
+  killer1 = ss.killers[0];
+  killer2 = ss.killers[1];
   depth = d;
   movesPicked = 0;
   numOfMoves = 0;
   numOfBadCaptures = 0;
 
   // With EvalInfo we are able to know how many captures are possible before
-  // generating them. So avoid generating them in case we know are zero.
+  // generating them. So avoid generating in case we know are zero.
   Color us = pos.side_to_move();
   Color them = opposite_color(us);
-  bool noAttacks = ei && (ei->attackedBy[us][0] & pos.pieces_of_color(them)) == 0;
-  bool noCaptures = noAttacks && (pos.ep_square() == SQ_NONE) && !pos.has_pawn_on_7th(us);
+  bool noCaptures =    ei
+                   && (ei->attackedBy[us][0] & pos.pieces_of_color(them)) == 0
+                   && !ei->mi->specialized_eval_exists()
+                   && (pos.ep_square() == SQ_NONE)
+                   && !pos.has_pawn_on_7th(us);
 
   if (p.is_check())
       phaseIndex = EvasionsPhaseIndex;
@@ -93,7 +96,6 @@ MovePicker::MovePicker(const Position& p, bool pv, Move ttm,
   else
       phaseIndex = (noCaptures ? NoMovesPhaseIndex : QsearchWithoutChecksPhaseIndex);
 
-
   dc = p.discovered_check_candidates(us);
   pinned = p.pinned_pieces(p.side_to_move());
 
@@ -226,18 +228,29 @@ void MovePicker::score_captures() {
   // to the badCaptures[] array.
   Move m;
   int seeValue;
+  Square from, to;
 
   for (int i = 0; i < numOfMoves; i++)
   {
       m = moves[i].move;
-      seeValue = pos.see(m);
+      from = move_from(m);
+      to = move_to(m);
+
+      bool hxl = ( int(pos.midgame_value_of_piece_on(from))
+                  -int(pos.midgame_value_of_piece_on(to)) > 0)
+                || pos.type_of_piece_on(from) == KING;
+
+      // Avoid calling see() for LxH and equal captures because
+      // SEE is always >= 0 and we order for MVV/LVA anyway.
+      seeValue = (hxl ? pos.see(m) : 0);
+
       if (seeValue >= 0)
       {
           if (move_promotion(m))
               moves[i].score = QueenValueMidgame;
           else
-              moves[i].score = int(pos.midgame_value_of_piece_on(move_to(m)))
-                              -int(pos.type_of_piece_on(move_from(m)));
+              moves[i].score = int(pos.midgame_value_of_piece_on(to))
+                              -int(pos.type_of_piece_on(from));
       }
       else
       {
@@ -268,10 +281,11 @@ void MovePicker::score_noncaptures() {
       else
           hs = H.move_ordering_score(pos.piece_on(move_from(m)), m);
 
-      // Ensure moves in history are always sorted as first
+      // Ensure history is always preferred to pst
       if (hs > 0)
           hs += 1000;
 
+      // pst based scoring
       moves[i].score = hs + pos.mg_pst_delta(m);
   }
 }
@@ -290,7 +304,6 @@ void MovePicker::score_evasions() {
       } else
           moves[i].score = H.move_ordering_score(pos.piece_on(move_from(m)), m);
   }
-  // FIXME try psqt also here
 }
 
 void MovePicker::score_qcaptures() {