LMR Simplification

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index c6d63c7bd2148ebfaa266b01b569dcfa7eb7d9c4..5f0a0f3b901e1bbdbbafd89ebafd98e0ea5950f9 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1019,19 +1019,18 @@ moves_loop: // When in check search starts from here
           if (!PvNode && cutNode)
               r += ONE_PLY;
 
-          // Decrease/increase reduction for moves with a good/bad history
-          int rHist = (val - 10000) / 20000;
-          r = std::max(DEPTH_ZERO, r - rHist * ONE_PLY);
-
           // Decrease reduction for moves that escape a capture. Filter out
           // castling moves, because they are coded as "king captures rook" and
           // hence break make_move(). Also use see() instead of see_sign(),
           // because the destination square is empty.
-          if (   r
-              && type_of(move) == NORMAL
-              && type_of(pos.piece_on(to_sq(move))) != PAWN
-              && pos.see(make_move(to_sq(move), from_sq(move))) < VALUE_ZERO)
-              r = std::max(DEPTH_ZERO, r - ONE_PLY);
+          else if (   type_of(move) == NORMAL
+                   && type_of(pos.piece_on(to_sq(move))) != PAWN
+                   && pos.see(make_move(to_sq(move), from_sq(move))) < VALUE_ZERO)
+              r -= ONE_PLY;
+
+          // Decrease/increase reduction for moves with a good/bad history
+          int rHist = (val - 10000) / 20000;
+          r = std::max(DEPTH_ZERO, r - rHist * ONE_PLY);
 
           Depth d = std::max(newDepth - r, ONE_PLY);