From: Steinar H. Gunderson <sgunderson@bigfoot.com>
Date: Mon, 12 Aug 2019 17:45:19 +0000 (+0200)
Subject: Revert "Revert "Revert "Shuffle detection #2064"""
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=59f7ecdea273442f1c06569f05632cac0000f93f;hp=d4062bbfa6c71e23fc6fb3f04e043409e8e41df7

Revert "Revert "Revert "Shuffle detection #2064"""

This reverts commit ca6ce6398b1bd21ff2ac29b2dc27d7c25abbb509.
---

diff --git a/src/search.cpp b/src/search.cpp
index 53f61a97..98419b20 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -662,15 +662,6 @@ namespace {
             : ttHit    ? tte->move() : MOVE_NONE;
     ttPv = PvNode || (ttHit && tte->is_pv());
 
-    // if position has been searched at higher depths and we are shuffling, return value_draw
-    if (pos.rule50_count() > 36
-        && ss->ply > 36
-        && depth < 3 * ONE_PLY
-        && ttHit
-        && tte->depth() > depth
-        && pos.count<PAWN>() > 0)
-        return VALUE_DRAW;
-
     // At non-PV nodes we check for an early TT cutoff
     if (  !PvNode
         && ttHit
@@ -998,10 +989,6 @@ moves_loop: // When in check, search starts from here
                && (pos.is_discovery_check_on_king(~us, move) || pos.see_ge(move)))
           extension = ONE_PLY;
 
-      // Shuffle extension
-      else if(pos.rule50_count() > 14 && ss->ply > 14 && depth < 3 * ONE_PLY && PvNode)
-          extension = ONE_PLY;
-
       // Castling extension
       else if (type_of(move) == CASTLING)
           extension = ONE_PLY;