Re-arrange history update code

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 374f6e6fe836bce8e689144f9dea32caf96c2576..08a779565289767d1fa56b63e03671d77ac970fe 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -826,7 +826,7 @@ moves_loop: // When in check and at SpNode search starts from here
               continue;
 
           moveCount = ++splitPoint->moveCount;
-          splitPoint->mutex.unlock();
+          splitPoint->spinlock.release();
       }
       else
           ++moveCount;
@@ -895,7 +895,7 @@ moves_loop: // When in check and at SpNode search starts from here
               && moveCount >= FutilityMoveCounts[improving][depth])
           {
               if (SpNode)
-                  splitPoint->mutex.lock();
+                  splitPoint->spinlock.acquire();
 
               continue;
           }
@@ -914,7 +914,7 @@ moves_loop: // When in check and at SpNode search starts from here
 
                   if (SpNode)
                   {
-                      splitPoint->mutex.lock();
+                      splitPoint->spinlock.acquire();
                       if (bestValue > splitPoint->bestValue)
                           splitPoint->bestValue = bestValue;
                   }
@@ -926,7 +926,7 @@ moves_loop: // When in check and at SpNode search starts from here
           if (predictedDepth < 4 * ONE_PLY && pos.see_sign(move) < VALUE_ZERO)
           {
               if (SpNode)
-                  splitPoint->mutex.lock();
+                  splitPoint->spinlock.acquire();
 
               continue;
           }
@@ -1026,7 +1026,7 @@ moves_loop: // When in check and at SpNode search starts from here
       // Step 18. Check for new best move
       if (SpNode)
       {
-          splitPoint->mutex.lock();
+          splitPoint->spinlock.acquire();
           bestValue = splitPoint->bestValue;
           alpha = splitPoint->alpha;
       }
@@ -1396,8 +1396,8 @@ moves_loop: // When in check and at SpNode search starts from here
     *pv = MOVE_NONE;
   }
 
-  // update_stats() updates killers, history, countermoves and followupmoves stats after a fail-high
-  // of a quiet move.
+  // update_stats() updates killers, history, countermoves and followupmoves
+  // stats after a fail-high of a quiet move.
 
   void update_stats(const Position& pos, Stack* ss, Move move, Depth depth, Move* quiets, int quietsCnt) {
 
@@ -1407,36 +1407,32 @@ moves_loop: // When in check and at SpNode search starts from here
         ss->killers[0] = move;
     }
 
-    // Increase history value of the cut-off move and decrease all the other
-    // played quiet moves.
     Value bonus = Value((depth / ONE_PLY) * (depth / ONE_PLY));
+
+    Square prevSq = to_sq((ss-1)->currentMove);
+    HistoryStats& cmh = CounterMovesHistory[pos.piece_on(prevSq)][prevSq];
+
     History.update(pos.moved_piece(move), to_sq(move), bonus);
 
-    for (int i = 0; i < quietsCnt; ++i)
+    if (is_ok((ss-1)->currentMove))
     {
-        Move m = quiets[i];
-        History.update(pos.moved_piece(m), to_sq(m), -bonus);
+        Countermoves.update(pos.piece_on(prevSq), prevSq, move);
+        cmh.update(pos.moved_piece(move), to_sq(move), bonus);
     }
 
-    if (is_ok((ss-1)->currentMove))
+    // Decrease all the other played quiet moves
+    for (int i = 0; i < quietsCnt; ++i)
     {
-        Square prevMoveSq = to_sq((ss-1)->currentMove);
-        Piece prevMovePiece = pos.piece_on(prevMoveSq);
-        Countermoves.update(prevMovePiece, prevMoveSq, move);
+        History.update(pos.moved_piece(quiets[i]), to_sq(quiets[i]), -bonus);
 
-        HistoryStats& cmh = CounterMovesHistory[prevMovePiece][prevMoveSq];
-        cmh.update(pos.moved_piece(move), to_sq(move), bonus);
-        for (int i = 0; i < quietsCnt; ++i)
-        {
-            Move m = quiets[i];
-            cmh.update(pos.moved_piece(m), to_sq(m), -bonus);
-        }
+        if (is_ok((ss-1)->currentMove))
+            cmh.update(pos.moved_piece(quiets[i]), to_sq(quiets[i]), -bonus);
     }
 
     if (is_ok((ss-2)->currentMove) && (ss-1)->currentMove == (ss-1)->ttMove)
     {
-        Square prevOwnMoveSq = to_sq((ss-2)->currentMove);
-        Followupmoves.update(pos.piece_on(prevOwnMoveSq), prevOwnMoveSq, move);
+        Square prevPrevSq = to_sq((ss-2)->currentMove);
+        Followupmoves.update(pos.piece_on(prevPrevSq), prevPrevSq, move);
     }
   }
 
@@ -1630,7 +1626,7 @@ void Thread::idle_loop() {
           std::memcpy(ss-2, sp->ss-2, 5 * sizeof(Stack));
           ss->splitPoint = sp;
 
-          sp->mutex.lock();
+          sp->spinlock.acquire();
 
           assert(activePosition == nullptr);
 
@@ -1659,7 +1655,7 @@ void Thread::idle_loop() {
           // After releasing the lock we can't access any SplitPoint related data
           // in a safe way because it could have been released under our feet by
           // the sp master.
-          sp->mutex.unlock();
+          sp->spinlock.release();
 
           // Try to late join to another split point if none of its slaves has
           // already finished.
@@ -1699,12 +1695,12 @@ void Thread::idle_loop() {
               sp = bestSp;
 
               // Recheck the conditions under lock protection
-              sp->mutex.lock();
+              sp->spinlock.acquire();
 
               if (   sp->allSlavesSearching
                   && sp->slavesMask.count() < MAX_SLAVES_PER_SPLITPOINT)
               {
-                  allocMutex.lock();
+                  spinlock.acquire();
 
                   if (can_join(sp))
                   {
@@ -1713,10 +1709,10 @@ void Thread::idle_loop() {
                       searching = true;
                   }
 
-                  allocMutex.unlock();
+                  spinlock.release();
               }
 
-              sp->mutex.unlock();
+              sp->spinlock.release();
           }
       }
   }
@@ -1767,7 +1763,7 @@ void check_time() {
           {
               SplitPoint& sp = th->splitPoints[i];
 
-              sp.mutex.lock();
+              sp.spinlock.acquire();
 
               nodes += sp.nodes;
 
@@ -1775,7 +1771,7 @@ void check_time() {
                   if (sp.slavesMask.test(idx) && Threads[idx]->activePosition)
                       nodes += Threads[idx]->activePosition->nodes_searched();
 
-              sp.mutex.unlock();
+              sp.spinlock.release();
           }
 
       if (nodes >= Limits.nodes)