From 9fd40b9ea887bbec989b0beee248d4ebf70705af Mon Sep 17 00:00:00 2001
From: Daniel Monroe <github.com@danielmonroe.net>
Date: Sun, 25 May 2025 10:34:52 -0700
Subject: [PATCH] Simplify tt depth in stat eval history adjustment

Passed simplification STC
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 102208 W: 26498 L: 26349 D: 49361
Ptnml(0-2): 284, 12095, 26166, 12306, 253
https://tests.stockfishchess.org/tests/view/683354c76ec7634154f9be88

Passed simplification LTC
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 133422 W: 34050 L: 33945 D: 65427
Ptnml(0-2): 56, 14473, 37559, 14556, 67
https://tests.stockfishchess.org/tests/view/683363626ec7634154f9c298

closes https://github.com/official-stockfish/Stockfish/pull/6099

Bench: 2652411
---
 src/search.cpp | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/search.cpp b/src/search.cpp
index c6f61ec9..670d343e 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -807,8 +807,7 @@ Value Search::Worker::search(
     }
 
     // Use static evaluation difference to improve quiet move ordering
-    if (((ss - 1)->currentMove).is_ok() && !(ss - 1)->inCheck && !priorCapture
-        && (ttData.depth - 2) <= depth)
+    if (((ss - 1)->currentMove).is_ok() && !(ss - 1)->inCheck && !priorCapture && ttData.depth <= 2)
     {
         int bonus = std::clamp(-10 * int((ss - 1)->staticEval + ss->staticEval), -1858, 1492) + 661;
         thisThread->mainHistory[~us][((ss - 1)->currentMove).from_to()] << bonus * 1057 / 1024;