X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=e02529327435b46f49f4780d591877b201042cbf;hp=c217e953715b48d1211efd43eb02f21521065fcc;hb=314faa905a60962595d610c26727c4b603c6ed62;hpb=bf395c6be180528cb3fc90d8b78dd5dd6f27adf6

diff --git a/src/search.cpp b/src/search.cpp
index c217e953..e0252932 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -310,7 +310,7 @@ namespace {
              Value *alpha, Value *beta, Value *bestValue,
              const Value futilityValue, const Value approximateValue,
              Depth depth, int *moves,
-             MovePicker *mp, Bitboard dcCandidates, int master, bool pvNode);
+             MovePicker *mp, int master, bool pvNode);
   void wake_sleeping_threads();
 
 #if !defined(_MSC_VER)
@@ -333,14 +333,14 @@ namespace {
 int perft(Position& pos, Depth depth)
 {
     Move move;
-    MovePicker mp = MovePicker(pos, MOVE_NONE, depth, H);
     int sum = 0;
+    MovePicker mp = MovePicker(pos, MOVE_NONE, depth, H);
 
     // If we are at the last ply we don't need to do and undo
     // the moves, just to count them.
     if (depth <= OnePly) // Replace with '<' to test also qsearch
     {
-        while ((move = mp.get_next_move()) != MOVE_NONE) sum++;
+        while (mp.get_next_move()) sum++;
         return sum;
     }
 
@@ -348,10 +348,10 @@ int perft(Position& pos, Depth depth)
     CheckInfo ci(pos);
     while ((move = mp.get_next_move()) != MOVE_NONE)
     {
-      StateInfo st;
-      pos.do_move(move, st, ci, pos.move_is_check(move, ci));
-      sum += perft(pos, depth - OnePly);
-      pos.undo_move(move);
+        StateInfo st;
+        pos.do_move(move, st, ci, pos.move_is_check(move, ci));
+        sum += perft(pos, depth - OnePly);
+        pos.undo_move(move);
     }
     return sum;
 }
@@ -1209,8 +1209,8 @@ namespace {
           && idle_thread_exists(threadID)
           && !AbortSearch
           && !thread_should_stop(threadID)
-          && split(pos, ss, ply, &alpha, &beta, &bestValue, VALUE_NONE, VALUE_NONE, depth,
-                   &moveCount, &mp, ci.dcCandidates, threadID, true))
+          && split(pos, ss, ply, &alpha, &beta, &bestValue, VALUE_NONE, VALUE_NONE,
+                   depth, &moveCount, &mp, threadID, true))
           break;
     }
 
@@ -1314,7 +1314,13 @@ namespace {
         ss[ply].currentMove = MOVE_NULL;
 
         pos.do_null_move(st);
-        int R = (depth >= 5 * OnePly ? 4 : 3); // Null move dynamic reduction
+
+        // Null move dynamic reduction based on depth
+        int R = (depth >= 5 * OnePly ? 4 : 3);
+
+        // Null move dynamic reduction based on value
+        if (approximateEval - beta > PawnValueMidgame)
+            R++;
 
         nullValue = -search(pos, ss, -(beta-1), depth-R*OnePly, ply+1, false, threadID);
 
@@ -1470,8 +1476,8 @@ namespace {
           && idle_thread_exists(threadID)
           && !AbortSearch
           && !thread_should_stop(threadID)
-          && split(pos, ss, ply, &beta, &beta, &bestValue, futilityValue, approximateEval, depth, &moveCount,
-                   &mp, ci.dcCandidates, threadID, false))
+          && split(pos, ss, ply, &beta, &beta, &bestValue, futilityValue, approximateEval,
+                   depth, &moveCount, &mp, threadID, false))
         break;
     }
 
@@ -2815,7 +2821,7 @@ namespace {
   bool split(const Position& p, SearchStack* sstck, int ply,
              Value* alpha, Value* beta, Value* bestValue, const Value futilityValue,
              const Value approximateEval, Depth depth, int* moves,
-             MovePicker* mp, Bitboard dcCandidates, int master, bool pvNode) {
+             MovePicker* mp, int master, bool pvNode) {
 
     assert(p.is_ok());
     assert(sstck != NULL);
@@ -2852,7 +2858,6 @@ namespace {
     splitPoint->alpha = pvNode? *alpha : (*beta - 1);
     splitPoint->beta = *beta;
     splitPoint->pvNode = pvNode;
-    splitPoint->dcCandidates = dcCandidates;
     splitPoint->bestValue = *bestValue;
     splitPoint->futilityValue = futilityValue;
     splitPoint->approximateEval = approximateEval;