Test Easy Move if no BestMoveChanges

In case we find a very good move after a
troubled start, we don't return immediately
anymore.

Tested directly at long TC where it passed:
LLR: 2.95 (-2.94,2.94) [0.00,6.00]
Total: 13910 W: 2397 L: 2228 D: 9285

bench: 7995098

diff --git a/src/search.cpp b/src/search.cpp
index e2ab9cd933db6bd0774c27a456985f92292db96a..c0a982363403ccae483d2fc5a00796e2323a06f6 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -19,6 +19,7 @@
 
 #include <algorithm>
 #include <cassert>
+#include <cfloat>
 #include <cmath>
 #include <cstring>
 #include <iostream>
@@ -440,6 +441,7 @@ namespace {
 
             // Stop search early if one move seems to be much better than others
             if (    depth >= 12
+                &&  BestMoveChanges <= DBL_EPSILON
                 && !stop
                 &&  PVSize == 1
                 &&  bestValue > VALUE_MATED_IN_MAX_PLY