generate_evasions() avoid to calculate pinned pieces

[stockfish] / src / movepick.cpp

diff --git a/src/movepick.cpp b/src/movepick.cpp
index d4242a300de7620e5f58665cb20c7e5ff0aa102c..671430708575ab1c6e2834ba9ce2e7c0594b0aa2 100644 (file)
--- a/src/movepick.cpp
+++ b/src/movepick.cpp
@@ -151,7 +151,7 @@ Move MovePicker::get_next_move() {
         break;
 
     case PH_BAD_CAPTURES:
-        badCapturesPicked = 0;
+        movesPicked = 0;
         break;
 
     case PH_NONCAPTURES:
@@ -162,7 +162,7 @@ Move MovePicker::get_next_move() {
 
     case PH_EVASIONS:
         assert(pos.is_check());
-        numOfMoves = generate_evasions(pos, moves);
+        numOfMoves = generate_evasions(pos, moves, pinned);
         score_evasions();
         movesPicked = 0;
         break;
@@ -310,17 +310,19 @@ void MovePicker::score_qcaptures() {
 }
 
 
-/// find_best_index() loops across the moves and returns index of\r
-/// the highest scored one. There is also a second version that\r
-/// lowers the priority of moves that attack the same square,\r
-/// so that if the best move that attack a square fails the next\r
+/// find_best_index() loops across the moves and returns index of
+/// the highest scored one. There is also a second version that
+/// lowers the priority of moves that attack the same square,
+/// so that if the best move that attack a square fails the next
 /// move picked attacks a different square if any, not the same one.
 
 int MovePicker::find_best_index() {
 
-  int bestScore = -10000000, bestIndex = -1;
+  assert(movesPicked < numOfMoves);
 
-  for (int i = movesPicked; i < numOfMoves; i++)
+  int bestIndex = movesPicked, bestScore = moves[movesPicked].score;
+
+  for (int i = movesPicked + 1; i < numOfMoves; i++)
       if (moves[i].score > bestScore)
       {
           bestIndex = i;
@@ -329,41 +331,43 @@ int MovePicker::find_best_index() {
   return bestIndex;
 }
 
-int MovePicker::find_best_index(Bitboard* squares, int values[]) {\r
-\r
-  int hs;\r
-  Move m;\r
-  Square to;\r
-  int bestScore = -10000000, bestIndex = -1;\r
-\r
-  for (int i = movesPicked; i < numOfMoves; i++)\r
-  {\r
-      m = moves[i].move;\r
-      to = move_to(m);\r
-      \r
-      if (!bit_is_set(*squares, to))\r
-      {\r
-          // Init at first use\r
-          set_bit(squares, to);\r
-          values[to] = 0;\r
-      }\r
-\r
-      hs = moves[i].score - values[to];\r
-      if (hs > bestScore)\r
-      {\r
-          bestIndex = i;\r
-          bestScore = hs;\r
-      }\r
-  }\r
-\r
-  if (bestIndex != -1)\r
-  {\r
-      // Raise value of the picked square, so next attack\r
-      // to the same square will get low priority.\r
-      to = move_to(moves[bestIndex].move);\r
-      values[to] += 0xB00;\r
-  }\r
-  return bestIndex;\r
+int MovePicker::find_best_index(Bitboard* squares, int values[]) {
+
+  assert(movesPicked < numOfMoves);
+
+  int hs;
+  Move m;
+  Square to;
+  int bestScore = -10000000, bestIndex = -1;
+
+  for (int i = movesPicked; i < numOfMoves; i++)
+  {
+      m = moves[i].move;
+      to = move_to(m);
+
+      if (!bit_is_set(*squares, to))
+      {
+          // Init at first use
+          set_bit(squares, to);
+          values[to] = 0;
+      }
+
+      hs = moves[i].score - values[to];
+      if (hs > bestScore)
+      {
+          bestIndex = i;
+          bestScore = hs;
+      }
+  }
+
+  if (bestIndex != -1)
+  {
+      // Raise value of the picked square, so next attack
+      // to the same square will get low priority.
+      to = move_to(moves[bestIndex].move);
+      values[to] += 0xB00;
+  }
+  return bestIndex;
 }
 
 
@@ -378,6 +382,7 @@ Move MovePicker::pick_move_from_list() {
   Move move;
 
   switch (PhaseTable[phaseIndex]) {
+
   case PH_GOOD_CAPTURES:
       assert(!pos.is_check());
       assert(movesPicked >= 0);
@@ -385,16 +390,12 @@ Move MovePicker::pick_move_from_list() {
       while (movesPicked < numOfMoves)
       {
           bestIndex = find_best_index();
-
-          if (bestIndex != -1) // Found a good capture
-          {
-              move = moves[bestIndex].move;
-              moves[bestIndex] = moves[movesPicked++];
-              if (   move != ttMove
-                  && move != mateKiller
-                  && pos.pl_move_is_legal(move, pinned))
-                  return move;
-          }
+          move = moves[bestIndex].move;
+          moves[bestIndex] = moves[movesPicked++];
+          if (   move != ttMove
+              && move != mateKiller
+              && pos.pl_move_is_legal(move, pinned))
+              return move;
       }
       break;
 
@@ -409,16 +410,12 @@ Move MovePicker::pick_move_from_list() {
           // been searched and it is not a PV node, we are probably failing low
           // anyway, so we just pick the first move from the list.
           bestIndex = (pvNode || movesPicked < 12) ? find_best_index() : movesPicked;
-
-          if (bestIndex != -1)
-          {
-              move = moves[bestIndex].move;
-              moves[bestIndex] = moves[movesPicked++];
-              if (   move != ttMove
-                  && move != mateKiller
-                  && pos.pl_move_is_legal(move, pinned))
-                  return move;
-          }
+          move = moves[bestIndex].move;
+          moves[bestIndex] = moves[movesPicked++];
+          if (   move != ttMove
+              && move != mateKiller
+              && pos.pl_move_is_legal(move, pinned))
+              return move;
       }
       break;
 
@@ -429,24 +426,20 @@ Move MovePicker::pick_move_from_list() {
       while (movesPicked < numOfMoves)
       {
           bestIndex = find_best_index();
-
-          if (bestIndex != -1)
-          {
-              move = moves[bestIndex].move;
-              moves[bestIndex] = moves[movesPicked++];
-              return move;
-          }
+          move = moves[bestIndex].move;
+          moves[bestIndex] = moves[movesPicked++];
+          return move;
     }
     break;
 
   case PH_BAD_CAPTURES:
       assert(!pos.is_check());
-      assert(badCapturesPicked >= 0);
+      assert(movesPicked >= 0);
       // It's probably a good idea to use SEE move ordering here, instead
       // of just picking the first move.  FIXME
-      while (badCapturesPicked < numOfBadCaptures)
+      while (movesPicked < numOfBadCaptures)
       {
-          move = badCaptures[badCapturesPicked++].move;
+          move = badCaptures[movesPicked++].move;
           if (   move != ttMove
               && move != mateKiller
               && pos.pl_move_is_legal(move, pinned))
@@ -460,16 +453,12 @@ Move MovePicker::pick_move_from_list() {
       while (movesPicked < numOfMoves)
       {
           bestIndex = (movesPicked < 4 ? find_best_index() : movesPicked);
-
-          if (bestIndex != -1)
-          {
-              move = moves[bestIndex].move;
-              moves[bestIndex] = moves[movesPicked++];
-              // Remember to change the line below if we decide to hash the qsearch!
-              // Maybe also postpone the legality check until after futility pruning?
-              if (/* move != ttMove && */ pos.pl_move_is_legal(move, pinned))
-                  return move;
-          }
+          move = moves[bestIndex].move;
+          moves[bestIndex] = moves[movesPicked++];
+          // Remember to change the line below if we decide to hash the qsearch!
+          // Maybe also postpone the legality check until after futility pruning?
+          if (/* move != ttMove && */ pos.pl_move_is_legal(move, pinned))
+              return move;
       }
       break;