From 4f4f78f86e8d44df2c13cfd6671f777dad516067 Mon Sep 17 00:00:00 2001
From: Michael Chaly <Vizvezdenec@gmail.com>
Date: Sat, 20 Sep 2025 09:29:19 +0300
Subject: [PATCH] Extend nodes pre qsearch only with deep enough tt entries

Modification of current pre qsearch extensions - allowing it only for deep enough tt entries.

Passed STC:
https://tests.stockfishchess.org/tests/view/68c954d302c43c969fe7eea5
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 35872 W: 9548 L: 9236 D: 17088
Ptnml(0-2): 101, 4075, 9295, 4341, 124

Passed LTC:
https://tests.stockfishchess.org/tests/view/68ca4e4f02c43c969fe7ef5f
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 107754 W: 27784 L: 27324 D: 52646
Ptnml(0-2): 47, 11528, 30300, 11922, 80

closes https://github.com/official-stockfish/Stockfish/pull/6324

bench: 2462792
---
 src/search.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/search.cpp b/src/search.cpp
index fbf493486..1ef01e5a6 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1260,7 +1260,7 @@ moves_loop:  // When in check, search starts here
             (ss + 1)->pv[0] = Move::none();
 
             // Extend move from transposition table if we are about to dive into qsearch.
-            if (move == ttData.move && rootDepth > 8)
+            if (move == ttData.move && ttData.depth > 1 && rootDepth > 8)
                 newDepth = std::max(newDepth, 1);
 
             value = -search<PV>(pos, ss + 1, -beta, -alpha, newDepth, false);