History code rewrite (#1122)
[stockfish] / src / search.cpp
index 2e8d5c6ff2ec3fbf530f78846822ad9805571eb6..aafbf80f94aef804009883e41bbfc8d28b96c3b6 100644 (file)
@@ -193,14 +193,15 @@ void Search::clear() {
 
   for (Thread* th : Threads)
   {
-      th->counterMoves.clear();
-      th->history.clear();
-      th->counterMoveHistory.clear();
       th->resetCalls = true;
+      th->counterMoves.fill(MOVE_NONE);
+      th->history.fill(0);
 
-      CounterMoveStats& cm = th->counterMoveHistory[NO_PIECE][0];
-      auto* t = &cm[NO_PIECE][0];
-      std::fill(t, t + sizeof(cm)/sizeof(*t), CounterMovePruneThreshold - 1);
+      for (auto& to : th->counterMoveHistory)
+          for (auto& h : to)
+              h.fill(0);
+
+      th->counterMoveHistory[NO_PIECE][0].fill(CounterMovePruneThreshold - 1);
   }
 
   Threads.main()->previousScore = VALUE_INFINITE;
@@ -334,7 +335,7 @@ void Thread::search() {
 
   std::memset(ss-4, 0, 7 * sizeof(Stack));
   for(int i = 4; i > 0; i--)
-     (ss-i)->counterMoves = &this->counterMoveHistory[NO_PIECE][0]; // Use as sentinel
+     (ss-i)->history = &this->counterMoveHistory[NO_PIECE][0]; // Use as sentinel
 
   bestValue = delta = alpha = -VALUE_INFINITE;
   beta = VALUE_INFINITE;
@@ -558,7 +559,7 @@ namespace {
     Thread* thisThread = pos.this_thread();
     inCheck = pos.checkers();
     moveCount = quietCount = ss->moveCount = 0;
-    ss->history = 0;
+    ss->statScore = 0;
     bestValue = -VALUE_INFINITE;
     ss->ply = (ss-1)->ply + 1;
 
@@ -607,7 +608,7 @@ namespace {
     assert(0 <= ss->ply && ss->ply < MAX_PLY);
 
     ss->currentMove = (ss+1)->excludedMove = bestMove = MOVE_NONE;
-    ss->counterMoves = &thisThread->counterMoveHistory[NO_PIECE][0];
+    ss->history = &thisThread->counterMoveHistory[NO_PIECE][0];
     (ss+2)->killers[0] = (ss+2)->killers[1] = MOVE_NONE;
     Square prevSq = to_sq((ss-1)->currentMove);
 
@@ -750,7 +751,7 @@ namespace {
         Depth R = ((823 + 67 * depth / ONE_PLY) / 256 + std::min((eval - beta) / PawnValueMg, 3)) * ONE_PLY;
 
         ss->currentMove = MOVE_NULL;
-        ss->counterMoves = &thisThread->counterMoveHistory[NO_PIECE][0];
+        ss->history = &thisThread->counterMoveHistory[NO_PIECE][0];
 
         pos.do_null_move(st);
         Value nullValue = depth-R < ONE_PLY ? -qsearch<NonPV, false>(pos, ss+1, -beta, -beta+1)
@@ -794,7 +795,7 @@ namespace {
             if (pos.legal(move))
             {
                 ss->currentMove = move;
-                ss->counterMoves = &thisThread->counterMoveHistory[pos.moved_piece(move)][to_sq(move)];
+                ss->history = &thisThread->counterMoveHistory[pos.moved_piece(move)][to_sq(move)];
 
                 pos.do_move(move, st);
                 value = -search<NonPV>(pos, ss+1, -rbeta, -rbeta+1, rdepth, !cutNode, false);
@@ -818,9 +819,9 @@ namespace {
 
 moves_loop: // When in check search starts from here
 
-    const CounterMoveStats& cmh = *(ss-1)->counterMoves;
-    const CounterMoveStats& fmh = *(ss-2)->counterMoves;
-    const CounterMoveStats& fm2 = *(ss-4)->counterMoves;
+    const PieceToHistory& cmh = *(ss-1)->history;
+    const PieceToHistory& fmh = *(ss-2)->history;
+    const PieceToHistory& fm2 = *(ss-4)->history;
 
     MovePicker mp(pos, ttMove, depth, ss);
     value = bestValue; // Workaround a bogus 'uninitialized' warning under gcc
@@ -956,7 +957,7 @@ moves_loop: // When in check search starts from here
 
       // Update the current move (this must be done after singular extension search)
       ss->currentMove = move;
-      ss->counterMoves = &thisThread->counterMoveHistory[moved_piece][to_sq(move)];
+      ss->history = &thisThread->counterMoveHistory[moved_piece][to_sq(move)];
 
       // Step 14. Make the move
       pos.do_move(move, st, givesCheck);
@@ -984,21 +985,21 @@ moves_loop: // When in check search starts from here
                        && !pos.see_ge(make_move(to_sq(move), from_sq(move))))
                   r -= 2 * ONE_PLY;
 
-              ss->history =  cmh[moved_piece][to_sq(move)]
-                           + fmh[moved_piece][to_sq(move)]
-                           + fm2[moved_piece][to_sq(move)]
-                           + thisThread->history.get(~pos.side_to_move(), move)
-                           - 4000; // Correction factor
+              ss->statScore =  cmh[moved_piece][to_sq(move)]
+                             + fmh[moved_piece][to_sq(move)]
+                             + fm2[moved_piece][to_sq(move)]
+                             + thisThread->history[~pos.side_to_move()][from_to(move)]
+                             - 4000; // Correction factor
 
               // Decrease/increase reduction by comparing opponent's stat score
-              if (ss->history > 0 && (ss-1)->history < 0)
+              if (ss->statScore > 0 && (ss-1)->statScore < 0)
                   r -= ONE_PLY;
 
-              else if (ss->history < 0 && (ss-1)->history > 0)
+              else if (ss->statScore < 0 && (ss-1)->statScore > 0)
                   r += ONE_PLY;
 
               // Decrease/increase reduction for moves with a good/bad history
-              r = std::max(DEPTH_ZERO, (r / ONE_PLY - ss->history / 20000) * ONE_PLY);
+              r = std::max(DEPTH_ZERO, (r / ONE_PLY - ss->statScore / 20000) * ONE_PLY);
           }
 
           Depth d = std::max(newDepth - r, ONE_PLY);
@@ -1399,7 +1400,7 @@ moves_loop: // When in check search starts from here
 
     for (int i : {1, 2, 4})
         if (is_ok((ss-i)->currentMove))
-            (ss-i)->counterMoves->update(pc, s, bonus);
+            (ss-i)->history->update(pc, s, bonus);
   }
 
 
@@ -1422,7 +1423,7 @@ moves_loop: // When in check search starts from here
     if (is_ok((ss-1)->currentMove))
     {
         Square prevSq = to_sq((ss-1)->currentMove);
-        thisThread->counterMoves.update(pos.piece_on(prevSq), prevSq, move);
+        thisThread->counterMoves[pos.piece_on(prevSq)][prevSq]=move;
     }
 
     // Decrease all the other played quiet moves