Remove std::pow from reduction. (#2234)

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index bd5ae75e0582145276a7f6d3f7681d7bf3e8d02f..df19108fb2db4dd28642c1ef20b34f49aa5f2a53 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -503,7 +503,7 @@ void Thread::search() {
 
           // If the bestMove is stable over several iterations, reduce time accordingly
           timeReduction = lastBestMoveDepth + 10 * ONE_PLY < completedDepth ? 1.95 : 1.0;
-          double reduction = std::pow(mainThread->previousTimeReduction, 0.528) / timeReduction;
+          double reduction = (1.25 + mainThread->previousTimeReduction) / (2.25 * timeReduction);
 
           // Use part of the gained time from a previous stable move for the current move
           for (Thread* th : Threads)