X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=8581b0b3792819cb392b9913bfe04bd64896ee15;hp=c09e23d687a19f34d4b74be3145805fd883bafb1;hb=351844061eddffac59e7a3c2d16af7ea9661bb3e;hpb=5c58d1f5cb4871595c07e6c2f6931780b5ac05b5

diff --git a/src/search.cpp b/src/search.cpp
index c09e23d6..8581b0b3 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -29,6 +29,7 @@
 #include "misc.h"
 #include "movegen.h"
 #include "movepick.h"
+#include "position.h"
 #include "search.h"
 #include "timeman.h"
 #include "thread.h"
@@ -505,7 +506,7 @@ void Thread::search() {
 
               if (   rootMoves.size() == 1
                   || Time.elapsed() > Time.optimum() * unstablePvFactor * improvingFactor / 628
-                  || (mainThread->easyMovePlayed = doEasyMove))
+                  || (mainThread->easyMovePlayed = doEasyMove, doEasyMove))
               {
                   // If we are allowed to ponder do not stop the search now but
                   // keep pondering until the GUI sends "ponderhit" or "stop".
@@ -844,8 +845,7 @@ moves_loop: // When in check search starts from here
     singularExtensionNode =   !rootNode
                            &&  depth >= 8 * ONE_PLY
                            &&  ttMove != MOVE_NONE
-                       /*  &&  ttValue != VALUE_NONE Already implicit in the next condition */
-                           &&  abs(ttValue) < VALUE_KNOWN_WIN
+                           &&  ttValue != VALUE_NONE
                            && !excludedMove // Recursive singular search is not allowed
                            && (tte->bound() & BOUND_LOWER)
                            &&  tte->depth() >= depth - 3 * ONE_PLY;
@@ -903,7 +903,7 @@ moves_loop: // When in check search starts from here
           && !extension
           &&  pos.legal(move))
       {
-          Value rBeta = ttValue - 2 * depth / ONE_PLY;
+          Value rBeta = std::max(ttValue - 2 * depth / ONE_PLY, -VALUE_MATE);
           Depth d = (depth / (2 * ONE_PLY)) * ONE_PLY;
           ss->excludedMove = move;
           ss->skipEarlyPruning = true;
@@ -920,8 +920,8 @@ moves_loop: // When in check search starts from here
 
       // Step 13. Pruning at shallow depth
       if (  !rootNode
-         && !inCheck
-         &&  bestValue > VALUE_MATED_IN_MAX_PLY)
+          && !inCheck
+          &&  bestValue > VALUE_MATED_IN_MAX_PLY)
       {
           if (   !captureOrPromotion
               && !givesCheck
@@ -1595,6 +1595,9 @@ bool RootMove::extract_ponder_from_tt(Position& pos)
 
     assert(pv.size() == 1);
 
+    if (!pv[0])
+        return false;
+
     pos.do_move(pv[0], st, pos.gives_check(pv[0]));
     TTEntry* tte = TT.probe(pos.key(), ttHit);