Simplify prior countermove bonus

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 44e13dae8d386f74a8a95f6aa4436b5c3b09d15a..e51e2f4dae122310673d40cfced2c5afaea79129 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1371,7 +1371,7 @@ moves_loop: // When in check, search starts here
     // Bonus for prior countermove that caused the fail low
     else if (!priorCapture && prevSq != SQ_NONE)
     {
-        int bonus = (depth > 5) + (PvNode || cutNode) + (bestValue < alpha - 113 * depth) + ((ss-1)->moveCount > 12);
+        int bonus = (depth > 5) + (PvNode || cutNode) + (bestValue < alpha - 800) + ((ss-1)->moveCount > 12);
         update_continuation_histories(ss-1, pos.piece_on(prevSq), prevSq, stat_bonus(depth) * bonus);
         thisThread->mainHistory[~us][from_to((ss-1)->currentMove)] << stat_bonus(depth) * bonus / 2;
     }