Don't update seldepth in qsearch, and added non sufficient material check in search

bobsquared · bobsquared · commit 1c2b454284a9 · 2021-03-15T19:01:39.000-07:00
diff --git a/src/search.cpp b/src/search.cpp
@@ -155,7 +155,6 @@ int qsearch(Bitboard &b, ThreadSearch *th, int depth, int alpha, int beta, int p
     #endif
 
     th->nodes++; // update nodes searched
-    th->seldepth = std::max(ply, th->seldepth); // update seldepth
 
     // stop the search
     #ifndef TUNER
@@ -296,6 +295,14 @@ int pvSearch(Bitboard &b, ThreadSearch *th, int depth, int alpha, int beta, bool
 
     th->seldepth = std::max(ply, th->seldepth); // update seldepth
 
+    // Check if there are any potential wins that don't require help mate.
+    if (beta > 0 && b.noPotentialWin()) {
+        if (alpha >= 0) {
+            th->nodes++;
+            return 0;
+        }
+    }
+
     // Dive into Quiesence search
     if (depth <= 0) {
         return qsearch(b, th, depth - 1, alpha, beta, ply);
