X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=433129d9b5737659cacc8a9307d803a9a0e2d30d;hp=a9e76c452d9ae958603d7bc3efa7ca7dac8ce05c;hb=9da3b44ddc7bc9ea7094b91663cbc0f8319c46be;hpb=72a501c6fe5e4e7b61291e9603d0c6cc0902e618

diff --git a/src/search.cpp b/src/search.cpp
index a9e76c45..433129d9 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -75,14 +75,17 @@ namespace {
   int FutilityMoveCounts[2][16]; // [improving][depth]
   int Reductions[2][2][64][64];  // [pv][improving][depth][moveNumber]
 
+  // Threshold used for countermoves based pruning.
+  const int CounterMovePruneThreshold = 0;
+
   template <bool PvNode> Depth reduction(bool i, Depth d, int mn) {
     return Reductions[PvNode][i][std::min(d / ONE_PLY, 63)][std::min(mn, 63)] * ONE_PLY;
   }
 
   // History and stats update bonus, based on depth
-  Value stat_bonus(Depth depth) {
+  int stat_bonus(Depth depth) {
     int d = depth / ONE_PLY ;
-    return d > 17 ? VALUE_ZERO : Value(d * d + 2 * d - 2);
+    return d > 17 ? 0 : d * d + 2 * d - 2;
   }
 
   // Skill structure is used to implement strength limit
@@ -148,8 +151,8 @@ namespace {
   Value value_to_tt(Value v, int ply);
   Value value_from_tt(Value v, int ply);
   void update_pv(Move* pv, Move move, Move* childPv);
-  void update_cm_stats(Stack* ss, Piece pc, Square s, Value bonus);
-  void update_stats(const Position& pos, Stack* ss, Move move, Move* quiets, int quietsCnt, Value bonus);
+  void update_cm_stats(Stack* ss, Piece pc, Square s, int bonus);
+  void update_stats(const Position& pos, Stack* ss, Move move, Move* quiets, int quietsCnt, int bonus);
   void check_time();
 
 } // namespace
@@ -175,8 +178,8 @@ void Search::init() {
 
   for (int d = 0; d < 16; ++d)
   {
-      FutilityMoveCounts[0][d] = int(2.4 + 0.773 * pow(d + 0.00, 1.8));
-      FutilityMoveCounts[1][d] = int(2.9 + 1.045 * pow(d + 0.49, 1.8));
+      FutilityMoveCounts[0][d] = int(2.4 + 0.74 * pow(d, 1.78));
+      FutilityMoveCounts[1][d] = int(5.0 + 1.00 * pow(d, 2.00));
   }
 }
 
@@ -192,6 +195,7 @@ void Search::clear() {
       th->counterMoves.clear();
       th->history.clear();
       th->counterMoveHistory.clear();
+      th->counterMoveHistory[NO_PIECE][0].fill(CounterMovePruneThreshold-1);
       th->resetCalls = true;
   }
 
@@ -550,7 +554,7 @@ namespace {
     Thread* thisThread = pos.this_thread();
     inCheck = pos.checkers();
     moveCount = quietCount =  ss->moveCount = 0;
-    ss->history = VALUE_ZERO;
+    ss->history = 0;
     bestValue = -VALUE_INFINITE;
     ss->ply = (ss-1)->ply + 1;
 
@@ -635,7 +639,7 @@ namespace {
             // Penalty for a quiet ttMove that fails low
             else if (!pos.capture_or_promotion(ttMove))
             {
-                Value penalty = -stat_bonus(depth);
+                int penalty = -stat_bonus(depth);
                 thisThread->history.update(pos.side_to_move(), ttMove, penalty);
                 update_cm_stats(ss, pos.moved_piece(ttMove), to_sq(ttMove), penalty);
             }
@@ -812,9 +816,6 @@ 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 bool cm_ok = is_ok((ss-1)->currentMove);
-    const bool fm_ok = is_ok((ss-2)->currentMove);
-    const bool f2_ok = is_ok((ss-4)->currentMove);
 
     MovePicker mp(pos, ttMove, depth, ss);
     value = bestValue; // Workaround a bogus 'uninitialized' warning under gcc
@@ -916,9 +917,8 @@ moves_loop: // When in check search starts from here
 
               // Countermoves based pruning
               if (   lmrDepth < 3
-                  && ((cmh[moved_piece][to_sq(move)] < VALUE_ZERO) || !cm_ok)
-                  && ((fmh[moved_piece][to_sq(move)] < VALUE_ZERO) || !fm_ok)
-                  && ((fm2[moved_piece][to_sq(move)] < VALUE_ZERO) || !f2_ok || (cm_ok && fm_ok)))
+                  && (cmh[moved_piece][to_sq(move)] < CounterMovePruneThreshold)
+                  && (fmh[moved_piece][to_sq(move)] < CounterMovePruneThreshold))
                   continue;
 
               // Futility pruning: parent node
@@ -985,10 +985,10 @@ moves_loop: // When in check search starts from here
                            - 4000; // Correction factor
 
               // Decrease/increase reduction by comparing opponent's stat score
-              if (ss->history > VALUE_ZERO && (ss-1)->history < VALUE_ZERO)
+              if (ss->history > 0 && (ss-1)->history < 0)
                   r -= ONE_PLY;
 
-              else if (ss->history < VALUE_ZERO && (ss-1)->history > VALUE_ZERO)
+              else if (ss->history < 0 && (ss-1)->history > 0)
                   r += ONE_PLY;
 
               // Decrease/increase reduction for moves with a good/bad history
@@ -1123,7 +1123,7 @@ moves_loop: // When in check search starts from here
     // Bonus for prior countermove that caused the fail low
     else if (    depth >= 3 * ONE_PLY
              && !pos.captured_piece()
-             && cm_ok)
+             && is_ok((ss-1)->currentMove))
         update_cm_stats(ss-1, pos.piece_on(prevSq), prevSq, stat_bonus(depth));
 
     if(!excludedMove)
@@ -1382,7 +1382,7 @@ moves_loop: // When in check search starts from here
 
   // update_cm_stats() updates countermove and follow-up move history
 
-  void update_cm_stats(Stack* ss, Piece pc, Square s, Value bonus) {
+  void update_cm_stats(Stack* ss, Piece pc, Square s, int bonus) {
 
     for (int i : {1, 2, 4})
         if (is_ok((ss-i)->currentMove))
@@ -1393,7 +1393,7 @@ moves_loop: // When in check search starts from here
   // update_stats() updates move sorting heuristics when a new quiet best move is found
 
   void update_stats(const Position& pos, Stack* ss, Move move,
-                    Move* quiets, int quietsCnt, Value bonus) {
+                    Move* quiets, int quietsCnt, int bonus) {
 
     if (ss->killers[0] != move)
     {