From 4fcfb0b4b7406004cd8adcf7de0b4acabe63c6c1 Mon Sep 17 00:00:00 2001
From: FauziAkram <fauzi.dabat@hotmail.com>
Date: Sun, 27 Jul 2025 19:08:07 +0300
Subject: [PATCH] Tweak the logic for setting the improving flag

Tweak the logic for setting the improving flag when the static evaluation is significantly higher than alpha.

Passed STC:
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 92320 W: 24057 L: 23664 D: 44599
Ptnml(0-2): 247, 10689, 23893, 11086, 245
https://tests.stockfishchess.org/tests/view/68860aba966ed85face248a1

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 281292 W: 72496 L: 71683 D: 137113
Ptnml(0-2): 135, 30289, 78995, 31082, 145
https://tests.stockfishchess.org/tests/view/6886168c966ed85face24962

closes https://github.com/official-stockfish/Stockfish/pull/6180

Bench: 3200439
---
 src/search.cpp | 11 ++++++-----
 src/search.h   |  3 ++-
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/search.cpp b/src/search.cpp
index 27a4bea67..9855d12e1 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -520,14 +520,15 @@ void Search::Worker::do_move(Position& pos, const Move move, StateInfo& st, Stac
     do_move(pos, move, st, pos.gives_check(move), ss);
 }
 
-void Search::Worker::do_move(Position& pos, const Move move, StateInfo& st, const bool givesCheck, Stack* const ss) {
-    bool capture = pos.capture_stage(move);
-    DirtyPiece dp = pos.do_move(move, st, givesCheck, &tt);
+void Search::Worker::do_move(
+  Position& pos, const Move move, StateInfo& st, const bool givesCheck, Stack* const ss) {
+    bool       capture = pos.capture_stage(move);
+    DirtyPiece dp      = pos.do_move(move, st, givesCheck, &tt);
     nodes.fetch_add(1, std::memory_order_relaxed);
     accumulatorStack.push(dp);
     if (ss != nullptr)
     {
-        ss->currentMove = move;
+        ss->currentMove         = move;
         ss->continuationHistory = &continuationHistory[ss->inCheck][capture][dp.pc][move.to_sq()];
         ss->continuationCorrectionHistory = &continuationCorrectionHistory[dp.pc][move.to_sq()];
     }
@@ -893,7 +894,7 @@ Value Search::Worker::search(
         }
     }
 
-    improving |= ss->staticEval >= beta + 87;
+    improving |= ss->staticEval >= beta + 94 * !PvNode;
 
     // Step 10. Internal iterative reductions
     // At sufficient depth, reduce depth for PV/Cut nodes without a TTMove.
diff --git a/src/search.h b/src/search.h
index a43649e94..07fc74317 100644
--- a/src/search.h
+++ b/src/search.h
@@ -298,7 +298,8 @@ class Worker {
     void iterative_deepening();
 
     void do_move(Position& pos, const Move move, StateInfo& st, Stack* const ss);
-    void do_move(Position& pos, const Move move, StateInfo& st, const bool givesCheck, Stack* const ss);
+    void
+    do_move(Position& pos, const Move move, StateInfo& st, const bool givesCheck, Stack* const ss);
     void do_null_move(Position& pos, StateInfo& st);
     void undo_move(Position& pos, const Move move);
     void undo_null_move(Position& pos);