Ensure move_importance() is non-zero

[stockfish] / src / material.cpp

diff --git a/src/material.cpp b/src/material.cpp
index d5d670ba27324dbe3d1164a29fae18535f3be6a1..a1eff233302982c1a6728da40c603075864dc5a2 100644 (file)
--- a/src/material.cpp
+++ b/src/material.cpp
@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -246,6 +246,16 @@ Entry* probe(const Position& pos, Table& entries, Endgames& endgames) {
       (npm_w == npm_b || npm_b < RookValueMg ? 0 : NoPawnsSF[std::min(pos.count<BISHOP>(BLACK), 2)]);
   }
 
+  if (pos.count<PAWN>(WHITE) == 1 && npm_w - npm_b <= BishopValueMg)
+  {
+      e->factor[WHITE] = (uint8_t) SCALE_FACTOR_ONEPAWN;
+  }
+
+  if (pos.count<PAWN>(BLACK) == 1 && npm_b - npm_w <= BishopValueMg)
+  {
+      e->factor[BLACK] = (uint8_t) SCALE_FACTOR_ONEPAWN;
+  }
+
   // Compute the space weight
   if (npm_w + npm_b >= 2 * QueenValueMg + 4 * RookValueMg + 2 * KnightValueMg)
   {