Unify best move update logic

Try to rewrite the Root case using as most as common
code as possible.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>

diff --git a/src/search.cpp b/src/search.cpp
index b0d359d1955ee4f707c427207c8b2852499135f9..0f937ed029d1fd749378c64e7326dc4edb4e44cc 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1192,14 +1192,14 @@ split_point_start: // At split points actual search starts from here
           alpha = sp->alpha;
       }
 
           alpha = sp->alpha;
       }
 

-      if (!Root && value > bestValue && !(SpNode && ThreadsMgr.cutoff_at_splitpoint(threadID)))
+      if (value > bestValue && !(SpNode && ThreadsMgr.cutoff_at_splitpoint(threadID)))

       {
           bestValue = value;
 
           if (SpNode)
               sp->bestValue = value;
 
       {
           bestValue = value;
 
           if (SpNode)
               sp->bestValue = value;
 

-          if (value > alpha)
+          if (!Root && value > alpha)

           {
               if (PvNode && value < beta) // We want always alpha < beta
               {
           {
               if (PvNode && value < beta) // We want always alpha < beta
               {


@@ -1223,10 +1223,6 @@ split_point_start: // At split points actual search starts from here
 
       if (Root)
       {
 
       if (Root)
       {

-          // To avoid to exit with bestValue == -VALUE_INFINITE
-          if (value > bestValue)
-              bestValue = value;
-

           // Finished searching the move. If StopRequest is true, the search
           // was aborted because the user interrupted the search or because we
           // ran out of time. In this case, the return value of the search cannot
           // Finished searching the move. If StopRequest is true, the search
           // was aborted because the user interrupted the search or because we
           // ran out of time. In this case, the return value of the search cannot


@@ -1238,13 +1234,9 @@ split_point_start: // At split points actual search starts from here
           // Remember searched nodes counts for this move
           mp.rm->nodes += pos.nodes_searched() - nodes;
 
           // Remember searched nodes counts for this move
           mp.rm->nodes += pos.nodes_searched() - nodes;
 

-          // Step 17. Check for new best move
-          if (!isPvMove && value <= alpha)
-              mp.rm->pv_score = -VALUE_INFINITE;
-          else
+          // PV move or new best move ?
+          if (isPvMove || value > alpha)

           {
           {

-              // PV move or new best move!
-

               // Update PV
               ss->bestMove = move;
               mp.rm->pv_score = value;
               // Update PV
               ss->bestMove = move;
               mp.rm->pv_score = value;


@@ -1264,9 +1256,11 @@ split_point_start: // At split points actual search starts from here
                   alpha = Rml[Min(moveCount, MultiPV) - 1].pv_score; // FIXME why moveCount?
               else if (value > alpha)
                   alpha = value;
                   alpha = Rml[Min(moveCount, MultiPV) - 1].pv_score; // FIXME why moveCount?
               else if (value > alpha)
                   alpha = value;

+          }
+          else
+              mp.rm->pv_score = -VALUE_INFINITE;

 
 

-          } // PV move or new best move
-      }
+      } // Root

 
       // Step 18. Check for split
       if (   !Root
 
       // Step 18. Check for split
       if (   !Root