diff --git a/src/search.cpp b/src/search.cpp index 77619345..5839763d 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -1184,8 +1184,11 @@ moves_loop: // When in check, search starts here // Do full depth search when reduced LMR search fails high if (value > alpha && d < newDepth) { + // Adjust full depth search based on LMR results - if result + // was good enough search deeper, if it was bad enough search shallower const bool doDeeperSearch = value > (alpha + 64 + 11 * (newDepth - d)); - value = -search(pos, ss+1, -(alpha+1), -alpha, newDepth + doDeeperSearch, !cutNode); + const bool doShallowerSearch = value < bestValue + newDepth; + value = -search(pos, ss+1, -(alpha+1), -alpha, newDepth + doDeeperSearch - doShallowerSearch, !cutNode); int bonus = value > alpha ? stat_bonus(newDepth) : -stat_bonus(newDepth);