X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fsearch.cpp;h=fa87f1c3f0f3a4aced851f4ef795d08c8f5a568d;hb=41c6a74d372799c6ed94b842db66f956d080e0b0;hp=0f524093c2d399c40ae08c25889f19aabf49b302;hpb=154e7afed0fe9c6f45a2aee8ef6f38d44076cb19;p=stockfish

diff --git a/src/search.cpp b/src/search.cpp
index 0f524093..fa87f1c3 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -309,7 +309,6 @@ void Thread::search() {
 
   complexityAverage.set(155, 1);
 
-  trend = SCORE_ZERO;
   optimism[us] = optimism[~us] = VALUE_ZERO;
 
   int searchAgainCounter = 0;
@@ -356,11 +355,7 @@ void Thread::search() {
               alpha = std::max(prev - delta,-VALUE_INFINITE);
               beta  = std::min(prev + delta, VALUE_INFINITE);
 
-              // Adjust trend and optimism based on root move's previousScore
-              int tr = 116 * prev / (std::abs(prev) + 89);
-              trend = (us == WHITE ?  make_score(tr, tr / 2)
-                                   : -make_score(tr, tr / 2));
-
+              // Adjust optimism based on root move's previousScore
               int opt = 118 * prev / (std::abs(prev) + 169);
               optimism[ us] = Value(opt);
               optimism[~us] = -optimism[us];
@@ -775,8 +770,7 @@ namespace {
     // Step 7. Razoring.
     // If eval is really low check with qsearch if it can exceed alpha, if it can't,
     // return a fail low.
-    if (   depth <= 7
-        && eval < alpha - 369 - 254 * depth * depth)
+    if (eval < alpha - 369 - 254 * depth * depth)
     {
         value = qsearch<NonPV>(pos, ss, alpha - 1, alpha);
         if (value < alpha)
@@ -789,7 +783,7 @@ namespace {
         &&  depth < 8
         &&  eval - futility_margin(depth, improving) - (ss-1)->statScore / 303 >= beta
         &&  eval >= beta
-        &&  eval < 28031) // larger than VALUE_KNOWN_WIN, but smaller than TB wins.
+        &&  eval < 28031) // larger than VALUE_KNOWN_WIN, but smaller than TB wins
         return eval;
 
     // Step 9. Null move search with verification search (~22 Elo)
@@ -1002,8 +996,7 @@ moves_loop: // When in check, search starts here
               || givesCheck)
           {
               // Futility pruning for captures (~0 Elo)
-              if (   !pos.empty(to_sq(move))
-                  && !givesCheck
+              if (   !givesCheck
                   && !PvNode
                   && lmrDepth < 7
                   && !ss->inCheck
@@ -1163,7 +1156,12 @@ moves_loop: // When in check, search starts here
           if (singularQuietLMR)
               r--;
 
-          // Increase reduction if next ply has a lot of fail high else reset count to 0
+          // Dicrease reduction if we move a threatened piece (~1 Elo)
+          if (   depth > 9
+              && (mp.threatenedPieces & from_sq(move)))
+              r--;
+
+          // Increase reduction if next ply has a lot of fail high
           if ((ss+1)->cutoffCnt > 3 && !PvNode)
               r++;
 
@@ -1174,7 +1172,7 @@ moves_loop: // When in check, search starts here
                          - 4433;
 
           // Decrease/increase reduction for moves with a good/bad history (~30 Elo)
-          r -= ss->statScore / 13628;
+          r -= ss->statScore / (13628 + 4000 * (depth > 7 && depth < 19));
 
           // In general we want to cap the LMR depth search at newDepth, but when
           // reduction is negative, we allow this move a limited search extension
@@ -1186,8 +1184,11 @@ moves_loop: // When in check, search starts here
           // Do full depth search when reduced LMR search fails high
           if (value > alpha && d < newDepth)
           {
+              // Adjust full depth search based on LMR results - if result
+              // was good enough search deeper, if it was bad enough search shallower
               const bool doDeeperSearch = value > (alpha + 64 + 11 * (newDepth - d));
-              value = -search<NonPV>(pos, ss+1, -(alpha+1), -alpha, newDepth + doDeeperSearch, !cutNode);
+              const bool doShallowerSearch = value < bestValue + newDepth;
+              value = -search<NonPV>(pos, ss+1, -(alpha+1), -alpha, newDepth + doDeeperSearch - doShallowerSearch, !cutNode);
 
               int bonus = value > alpha ?  stat_bonus(newDepth)
                                         : -stat_bonus(newDepth);
@@ -1294,8 +1295,6 @@ moves_loop: // When in check, search starts here
               }
           }
       }
-      else
-         ss->cutoffCnt = 0;
 
 
       // If the move is worse than some previously searched move, remember it to update its stats later
@@ -1545,8 +1544,8 @@ moves_loop: // When in check, search starts here
       // Continuation history based pruning (~2 Elo)
       if (   !capture
           && bestValue > VALUE_TB_LOSS_IN_MAX_PLY
-          && (*contHist[0])[pos.moved_piece(move)][to_sq(move)] < CounterMovePruneThreshold
-          && (*contHist[1])[pos.moved_piece(move)][to_sq(move)] < CounterMovePruneThreshold)
+          && (*contHist[0])[pos.moved_piece(move)][to_sq(move)] < 0
+          && (*contHist[1])[pos.moved_piece(move)][to_sq(move)] < 0)
           continue;
 
       // movecount pruning for quiet check evasions
@@ -1860,12 +1859,9 @@ string UCI::pv(const Position& pos, Depth depth, Value alpha, Value beta) {
           ss << (v >= beta ? " lowerbound" : v <= alpha ? " upperbound" : "");
 
       ss << " nodes "    << nodesSearched
-         << " nps "      << nodesSearched * 1000 / elapsed;
-
-      if (elapsed > 1000) // Earlier makes little sense
-          ss << " hashfull " << TT.hashfull();
-
-      ss << " tbhits "   << tbHits
+         << " nps "      << nodesSearched * 1000 / elapsed
+         << " hashfull " << TT.hashfull()
+         << " tbhits "   << tbHits
          << " time "     << elapsed
          << " pv";