From bebffc5622d8dba4c8db1fbc9ad7bac5b1d9012a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=D0=9A=D0=B8=D1=80=D0=B8=D0=BB=D0=BB=20=D0=97=D0=B0=D1=80?=
 =?UTF-8?q?=D0=B8=D0=BF=D0=BE=D0=B2?=
 <67618307+kokodio@users.noreply.github.com>
Date: Sun, 25 May 2025 17:13:01 +0500
Subject: [PATCH] Adjust futility pruning thresholds using history

Passed STC:
https://tests.stockfishchess.org/tests/view/6833095a6ec7634154f9b5b3
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 56896 W: 14946 L: 14604 D: 27346
Ptnml(0-2): 117, 6674, 14561, 6942, 154

Passed LTC:
https://tests.stockfishchess.org/tests/view/6833179d6ec7634154f9b5da
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 200742 W: 51660 L: 51012 D: 98070
Ptnml(0-2): 96, 21520, 56473, 22204, 78

Passed Non-regression SMP STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 29080 W: 7591 L: 7373 D: 14116
Ptnml(0-2): 38, 3178, 7881, 3414, 29
https://tests.stockfishchess.org/tests/view/6833689d6ec7634154f9c2ba

closes https://github.com/official-stockfish/Stockfish/pull/6092

Bench: 2305697
---
 AUTHORS        | 1 +
 src/search.cpp | 5 +++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/AUTHORS b/AUTHORS
index 8caa2285..be88a8e9 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -132,6 +132,7 @@ Kenneth Lee (kennethlee33)
 Kian E (KJE-98)
 kinderchocolate
 Kiran Panditrao (Krgp)
+Kirill Zaripov (kokodio)
 Kojirion
 Krisztián Peőcz
 Krystian Kuzniarek (kuzkry)
diff --git a/src/search.cpp b/src/search.cpp
index 5b16b269..10e24482 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1095,8 +1095,9 @@ moves_loop:  // When in check, search starts here
 
                 lmrDepth += history / 3388;
 
-                Value futilityValue = ss->staticEval + (bestMove ? 46 : 138) + 117 * lmrDepth
-                                    + 102 * (ss->staticEval > alpha);
+                Value baseFutility = (bestMove ? 46 : 138 + std::abs(history / 300));
+                Value futilityValue =
+                  ss->staticEval + baseFutility + 117 * lmrDepth + 102 * (ss->staticEval > alpha);
 
                 // Futility pruning: parent node
                 // (*Scaler): Generally, more frequent futility pruning