X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmovepick.cpp;h=b3f413bf1ffa0bd20255ccd5f25893839dfd1e45;hp=69d848d27564a0680e2c97d7baf97f02ef401dda;hb=6fa6da3ee13d2b7bdbec3cd24ff8ca43233c74fb;hpb=20d6a8e57f55e586f5ab8b3bcb60bfe17c5f2708

diff --git a/src/movepick.cpp b/src/movepick.cpp
index 69d848d2..b3f413bf 100644
--- a/src/movepick.cpp
+++ b/src/movepick.cpp
@@ -55,7 +55,7 @@ namespace {
   inline Move pick_best(ExtMove* begin, ExtMove* end)
   {
       std::swap(*begin, *std::max_element(begin, end));
-      return begin->move;
+      return *begin;
   }
 
 } // namespace
@@ -201,13 +201,28 @@ void MovePicker::generate_next_stage() {
 
   case KILLERS_S1:
       cur = killers;
-      endMoves = cur + 6;
-      killers[0].move = ss->killers[0];
-      killers[1].move = ss->killers[1];
-      killers[2].move = countermoves[0];
-      killers[3].move = countermoves[1];
-      killers[4].move = followupmoves[0];
-      killers[5].move = followupmoves[1];
+      endMoves = cur + 2;
+
+      killers[0] = ss->killers[0];
+      killers[1] = ss->killers[1];
+      killers[2].move = killers[3].move = MOVE_NONE;
+      killers[4].move = killers[5].move = MOVE_NONE;
+
+      // In SMP case countermoves[] and followupmoves[] could have duplicated entries
+      // in rare cases (less than 1 out of a million). This is harmless.
+
+      // Be sure countermoves and followupmoves are different from killers
+      for (int i = 0; i < 2; ++i)
+          if (   countermoves[i] != killers[0]
+              && countermoves[i] != killers[1])
+              *endMoves++ = countermoves[i];
+
+      for (int i = 0; i < 2; ++i)
+          if (   followupmoves[i] != killers[0]
+              && followupmoves[i] != killers[1]
+              && followupmoves[i] != killers[2]
+              && followupmoves[i] != killers[3])
+              *endMoves++ = followupmoves[i];
       break;
 
   case QUIETS_1_S1:
@@ -245,7 +260,7 @@ void MovePicker::generate_next_stage() {
       /* Fall through */
 
   case STOP:
-      endMoves = cur + 1; // Avoid another next_phase() call
+      endMoves = cur + 1; // Avoid another generate_next_stage() call
       break;
 
   default:
@@ -282,7 +297,7 @@ Move MovePicker::next_move<false>() {
                   return move;
 
               // Losing capture, move it to the tail of the array
-              (endBadCaptures--)->move = move;
+              *endBadCaptures-- = move;
           }
           break;
 
@@ -292,14 +307,7 @@ Move MovePicker::next_move<false>() {
               &&  move != ttMove
               &&  pos.pseudo_legal(move)
               && !pos.capture(move))
-          {
-              // Check for duplicated entries
-              for (int i = 0; i < cur - 1 - killers; i++)
-                  if (move == killers[i])
-                      goto skip;
               return move;
-          }
-      skip:
           break;
 
       case QUIETS_1_S1: case QUIETS_2_S1: