From: jhellis3 <jhellis3@gmail.com>
Date: Sun, 3 Mar 2013 21:13:05 +0000 (-0600)
Subject: Stop search if only 1 legal move
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=3ce43c20dee3d0c7afc4ff3b4c67e0530ab2138f;ds=sidebyside

Stop search if only 1 legal move

There is no point searching a move that is forced.
It wastes time while allowing computer opponents to
fill hash with 100% accuracy.

[edit: Condition moved together with "easy move" ones]

Bench identical: 4922272
---

diff --git a/src/search.cpp b/src/search.cpp
index 33fff82d..19ebc5e6 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -452,6 +452,7 @@ namespace {
                 && !stop
                 &&  PVSize == 1
                 && (   (bestMoveNeverChanged && recapture)
+                    || RootMoves.size() == 1
                     || Time::now() - SearchTime > (TimeMgr.available_time() * 40) / 100))
             {
                 Value rBeta = bestValue - 2 * PawnValueMg;