Reintroduce piece/square tables to score non-captures

[stockfish] / src / movepick.cpp

diff --git a/src/movepick.cpp b/src/movepick.cpp
index 8837bc469779c2892708d371dea20dfd679de469..2867e7664716ba32c6b5b0d90284a4e75f8ede15 100644 (file)
--- a/src/movepick.cpp
+++ b/src/movepick.cpp
@@ -39,7 +39,7 @@ namespace {
 
   /// Variables
 
-  MovePicker::MovegenPhase PhaseTable[32];  
+  MovePicker::MovegenPhase PhaseTable[32];
   int MainSearchPhaseIndex;
   int EvasionsPhaseIndex;
   int QsearchWithChecksPhaseIndex;
@@ -62,7 +62,7 @@ namespace {
 /// move ordering is at the current node.
 
 MovePicker::MovePicker(const Position& p, bool pvnode, Move ttm, Move mk,
-                       Move k1, Move k2, Depth d) : pos(p) {  
+                       Move k1, Move k2, Depth d) : pos(p) {
   pvNode = pvnode;
   ttMove = ttm;
   mateKiller = (mk == ttm)? MOVE_NONE : mk;
@@ -116,7 +116,7 @@ Move MovePicker::get_next_move() {
         if (ttMove != MOVE_NONE)
         {
             assert(move_is_ok(ttMove));
-            if (generate_move_if_legal(pos, ttMove, pinned) != MOVE_NONE)
+            if (move_is_legal(pos, ttMove, pinned))
                 return ttMove;
         }
         break;
@@ -125,7 +125,7 @@ Move MovePicker::get_next_move() {
         if (mateKiller != MOVE_NONE)
         {
             assert(move_is_ok(mateKiller));
-            if (generate_move_if_legal(pos, mateKiller, pinned) != MOVE_NONE)
+            if (move_is_legal(pos, mateKiller, pinned))
                 return mateKiller;
        }
        break;
@@ -147,13 +147,13 @@ Move MovePicker::get_next_move() {
         break;
 
     case PH_EVASIONS:
-        assert(pos.is_check());      
+        assert(pos.is_check());
         numOfMoves = generate_evasions(pos, moves);
         score_evasions();
         movesPicked = 0;
         break;
 
-    case PH_QCAPTURES:      
+    case PH_QCAPTURES:
         numOfMoves = generate_captures(pos, moves);
         score_qcaptures();
         movesPicked = 0;
@@ -172,8 +172,6 @@ Move MovePicker::get_next_move() {
         return MOVE_NONE;
     }
   }
-  assert(false);
-  return MOVE_NONE;
 }
 
 
@@ -192,7 +190,7 @@ Move MovePicker::get_next_move(Lock &lock) {
    if (m == MOVE_NONE)
        finished = true;
 
-   lock_release(&lock);   
+   lock_release(&lock);
    return m;
 }
 
@@ -228,16 +226,28 @@ void MovePicker::score_captures() {
 }
 
 void MovePicker::score_noncaptures() {
-
-  for (int i = 0; i < numOfMoves; i++)
-  {
-      Move m = moves[i].move;
-      if (m == killer1)
-          moves[i].score = HistoryMax + 2;
-      else if (m == killer2)
-          moves[i].score = HistoryMax + 1;
-      else
-         moves[i].score = H.move_ordering_score(pos.piece_on(move_from(m)), m);
+  // First score by history, when no history is available then use
+  // piece/square tables values. This seems to be better then a
+  // random choice when we don't have an history for any move.
+  Move m;\r
+  int hs;\r
+\r
+  for (int i = 0; i < numOfMoves; i++)\r
+  {\r
+      m = moves[i].move;\r
+\r
+      if (m == killer1)\r
+          hs = HistoryMax + 2;\r
+      else if (m == killer2)\r
+          hs = HistoryMax + 1;\r
+      else\r
+          hs = H.move_ordering_score(pos.piece_on(move_from(m)), m);\r
+\r
+      // Ensure moves in history are always sorted as first\r
+      if (hs > 0)\r
+          hs += 1000;\r
+\r
+      moves[i].score = hs + pos.mg_pst_delta(m);\r
   }
 }
 
@@ -273,20 +283,20 @@ void MovePicker::score_qcaptures() {
 }
 
 
-/// find_best_index() loops across the moves and returns index of\r
-/// the highest scored one.\r
-\r
-int MovePicker::find_best_index() {\r
-\r
-  int bestScore = -10000000, bestIndex = -1;\r
-\r
-  for (int i = movesPicked; i < numOfMoves; i++)\r
-      if (moves[i].score > bestScore)\r
-      {\r
-          bestIndex = i;\r
-          bestScore = moves[i].score;\r
-      }\r
-  return bestIndex;\r
+/// find_best_index() loops across the moves and returns index of
+/// the highest scored one.
+
+int MovePicker::find_best_index() {
+
+  int bestScore = -10000000, bestIndex = -1;
+
+  for (int i = movesPicked; i < numOfMoves; i++)
+      if (moves[i].score > bestScore)
+      {
+          bestIndex = i;
+          bestScore = moves[i].score;
+      }
+  return bestIndex;
 }
 
 
@@ -333,7 +343,7 @@ Move MovePicker::pick_move_from_list() {
               moves[bestIndex] = moves[movesPicked++];
               if (   move != ttMove
                   && move != mateKiller
-                  && pos.move_is_legal(move, pinned))
+                  && pos.pl_move_is_legal(move, pinned))
                   return move;
           }
       }
@@ -357,7 +367,7 @@ Move MovePicker::pick_move_from_list() {
               moves[bestIndex] = moves[movesPicked++];
               if (   move != ttMove
                   && move != mateKiller
-                  && pos.move_is_legal(move, pinned))
+                  && pos.pl_move_is_legal(move, pinned))
                   return move;
           }
       }
@@ -390,7 +400,7 @@ Move MovePicker::pick_move_from_list() {
           move = badCaptures[badCapturesPicked++].move;
           if (   move != ttMove
               && move != mateKiller
-              && pos.move_is_legal(move, pinned))
+              && pos.pl_move_is_legal(move, pinned))
               return move;
       }
       break;
@@ -408,7 +418,7 @@ Move MovePicker::pick_move_from_list() {
               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.move_is_legal(move, pinned))
+              if (/* move != ttMove && */ pos.pl_move_is_legal(move, pinned))
                   return move;
           }
       }
@@ -423,7 +433,7 @@ Move MovePicker::pick_move_from_list() {
       {
           move = moves[movesPicked++].move;
           // Remember to change the line below if we decide to hash the qsearch!
-          if (/* move != ttMove && */ pos.move_is_legal(move, pinned))
+          if (/* move != ttMove && */ pos.pl_move_is_legal(move, pinned))
               return move;
       }
       break;
@@ -435,8 +445,8 @@ Move MovePicker::pick_move_from_list() {
 }
 
 
-/// MovePicker::current_move_type() returns the type of the just\r
-/// picked next move. It can be used in search to further differentiate\r
+/// MovePicker::current_move_type() returns the type of the just
+/// picked next move. It can be used in search to further differentiate
 /// according to the current move type: capture, non capture, escape, etc.
 MovePicker::MovegenPhase MovePicker::current_move_type() const {