Simplify Away Quadruple Extensions

official-pikafish · May 18, 2024 · 30b05a0 · 30b05a0
1 parent 9ae2831
commit 30b05a0
Showing 1 changed file with 2 additions and 4 deletions.
diff --git a/src/search.cpp b/src/search.cpp
@@ -948,12 +948,10 @@ Value Search::Worker::search(
                 {
                     int doubleMargin = 251 * PvNode - 241 * !ttCapture;
                     int tripleMargin =
-                      135 + 234 * PvNode - 248 * !ttCapture + 124 * (ss->ttPv || !ttCapture);
-                    int quadMargin = 447 + 354 * PvNode - 300 * !ttCapture + 206 * ss->ttPv;
+                      121 + 238 * PvNode - 259 * !ttCapture + 117 * (ss->ttPv || !ttCapture);
 
                     extension = 1 + (value < singularBeta - doubleMargin)
-                              + (value < singularBeta - tripleMargin)
-                              + (value < singularBeta - quadMargin);
+                              + (value < singularBeta - tripleMargin);
 
                     depth += ((!PvNode) && (depth < 14));
                 }