Count all weak squares in the king ring with a single popcount

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index fbcae4601b3d071e1448456b847d1ce1de7b0840..09e12ed1bf2602dca0504e94d5a516d65f6cb33d 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -134,8 +134,8 @@ namespace {
       }
     }
 
-    int stableCnt;
     Key expectedPosKey;
+    int stableCnt;
     Move pv[3];
   };
 
@@ -154,6 +154,32 @@ namespace {
   void update_continuation_histories(Stack* ss, Piece pc, Square to, int bonus);
   void update_stats(const Position& pos, Stack* ss, Move move, Move* quiets, int quietsCnt, int bonus);
 
+  // perft() is our utility to verify move generation. All the leaf nodes up
+  // to the given depth are generated and counted, and the sum is returned.
+  template<bool Root>
+  uint64_t perft(Position& pos, Depth depth) {
+
+    StateInfo st;
+    uint64_t cnt, nodes = 0;
+    const bool leaf = (depth == 2 * ONE_PLY);
+
+    for (const auto& m : MoveList<LEGAL>(pos))
+    {
+        if (Root && depth <= ONE_PLY)
+            cnt = 1, nodes++;
+        else
+        {
+            pos.do_move(m, st);
+            cnt = leaf ? MoveList<LEGAL>(pos).size() : perft<false>(pos, depth - ONE_PLY);
+            nodes += cnt;
+            pos.undo_move(m);
+        }
+        if (Root)
+            sync_cout << UCI::move(m, pos.is_chess960()) << ": " << cnt << sync_endl;
+    }
+    return nodes;
+  }
+
 } // namespace
 
 
@@ -209,40 +235,18 @@ void Search::clear() {
 }
 
 
-/// Search::perft() is our utility to verify move generation. All the leaf nodes
-/// up to the given depth are generated and counted, and the sum is returned.
-template<bool Root>
-uint64_t Search::perft(Position& pos, Depth depth) {
-
-  StateInfo st;
-  uint64_t cnt, nodes = 0;
-  const bool leaf = (depth == 2 * ONE_PLY);
-
-  for (const auto& m : MoveList<LEGAL>(pos))
-  {
-      if (Root && depth <= ONE_PLY)
-          cnt = 1, nodes++;
-      else
-      {
-          pos.do_move(m, st);
-          cnt = leaf ? MoveList<LEGAL>(pos).size() : perft<false>(pos, depth - ONE_PLY);
-          nodes += cnt;
-          pos.undo_move(m);
-      }
-      if (Root)
-          sync_cout << UCI::move(m, pos.is_chess960()) << ": " << cnt << sync_endl;
-  }
-  return nodes;
-}
-
-template uint64_t Search::perft<true>(Position&, Depth);
-
-
 /// MainThread::search() is called by the main thread when the program receives
 /// the UCI 'go' command. It searches from the root position and outputs the "bestmove".
 
 void MainThread::search() {
 
+  if (Limits.perft)
+  {
+      nodes = perft<true>(rootPos, Limits.perft * ONE_PLY);
+      sync_cout << "\nNodes searched: " << nodes << "\n" << sync_endl;
+      return;
+  }
+
   Color us = rootPos.side_to_move();
   Time.init(Limits, us, rootPos.game_ply());
   TT.new_search();
@@ -904,7 +908,8 @@ moves_loop: // When in check search starts from here
               }
 
               // Reduced depth of the next LMR search
-              int lmrDepth = std::max(newDepth - reduction<PvNode>(improving, depth, moveCount), DEPTH_ZERO) / ONE_PLY;
+              int mch = std::max(1, moveCount - (ss-1)->moveCount / 16);
+              int lmrDepth = std::max(newDepth - reduction<PvNode>(improving, depth, mch), DEPTH_ZERO) / ONE_PLY;
 
               // Countermoves based pruning
               if (   lmrDepth < 3
@@ -955,7 +960,8 @@ moves_loop: // When in check search starts from here
           &&  moveCount > 1
           && (!captureOrPromotion || moveCountPruning))
       {
-          Depth r = reduction<PvNode>(improving, depth, moveCount);
+          int mch = std::max(1, moveCount - (ss-1)->moveCount / 16);
+          Depth r = reduction<PvNode>(improving, depth, mch);
 
           if (captureOrPromotion)
               r -= r ? ONE_PLY : DEPTH_ZERO;
@@ -1242,8 +1248,7 @@ moves_loop: // When in check search starts from here
     // to search the moves. Because the depth is <= 0 here, only captures,
     // queen promotions and checks (only if depth >= DEPTH_QS_CHECKS) will
     // be generated.
-    const PieceToHistory* contHist[4] = {};
-    MovePicker mp(pos, ttMove, depth, &pos.this_thread()->mainHistory, contHist, to_sq((ss-1)->currentMove));
+    MovePicker mp(pos, ttMove, depth, &pos.this_thread()->mainHistory, to_sq((ss-1)->currentMove));
 
     // Loop through the moves until no moves remain or a beta cutoff occurs
     while ((move = mp.next_move()) != MOVE_NONE)
@@ -1491,7 +1496,7 @@ moves_loop: // When in check search starts from here
     if (Threads.ponder)
         return;
 
-    if (   (Limits.use_time_management() && elapsed > Time.maximum() - 10)
+    if (   (Limits.use_time_management() && elapsed > Time.maximum())
         || (Limits.movetime && elapsed >= Limits.movetime)
         || (Limits.nodes && Threads.nodes_searched() >= (uint64_t)Limits.nodes))
             Threads.stop = true;