From ff10f4ac6516d691b5a48788bc7b21d0ecd83b03 Mon Sep 17 00:00:00 2001
From: Dubslow <bunslow@gmail.com>
Date: Wed, 12 Jun 2024 03:14:55 -0500
Subject: [PATCH 01/25] Fix readability of TTEntry occupancy check

Passed STC:
https://tests.stockfishchess.org/tests/view/66695b6a602682471b064cfc
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 107520 W: 28138 L: 27998 D: 51384
Ptnml(0-2): 373, 12257, 28358, 12401, 371

closes https://github.com/official-stockfish/Stockfish/pull/5394

No functional change
---
 src/tt.cpp | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/tt.cpp b/src/tt.cpp
index 763e2c9b3..30104ab7d 100644
--- a/src/tt.cpp
+++ b/src/tt.cpp
@@ -55,6 +55,7 @@ struct TTEntry {
                       Bound(genBound8 & 0x3), bool(genBound8 & 0x4)};
     }
 
+    bool is_occupied() const;
     void save(Key k, Value v, bool pv, Bound b, Depth d, Move m, Value ev, uint8_t generation8);
     // The returned age is a multiple of TranspositionTable::GENERATION_DELTA
     uint8_t relative_age(const uint8_t generation8) const;
@@ -84,7 +85,8 @@ static constexpr int GENERATION_MASK = (0xFF << GENERATION_BITS) & 0xFF;
 
 // DEPTH_ENTRY_OFFSET exists because 1) we use `bool(depth8)` as the occupancy check, but
 // 2) we need to store negative depths for QS. (`depth8` is the only field with "spare bits":
-// we sacrifice the ability to store depths greater than 1<<8 less the offset, as asserted below.)
+// we sacrifice the ability to store depths greater than 1<<8 less the offset, as asserted in `save`.)
+bool TTEntry::is_occupied() const { return bool(depth8); }
 
 // Populates the TTEntry with a new node's data, possibly
 // overwriting an old position. The update is not atomic and can be racy.
@@ -196,7 +198,7 @@ int TranspositionTable::hashfull() const {
     int cnt = 0;
     for (int i = 0; i < 1000; ++i)
         for (int j = 0; j < ClusterSize; ++j)
-            cnt += table[i].entry[j].depth8
+            cnt += table[i].entry[j].is_occupied()
                 && (table[i].entry[j].genBound8 & GENERATION_MASK) == generation8;
 
     return cnt / ClusterSize;
@@ -227,7 +229,7 @@ std::tuple<bool, TTData, TTWriter> TranspositionTable::probe(const Key key) cons
         if (tte[i].key16 == key16)
             // This gap is the main place for read races.
             // After `read()` completes that copy is final, but may be self-inconsistent.
-            return {bool(tte[i].depth8), tte[i].read(), TTWriter(&tte[i])};
+            return {tte[i].is_occupied(), tte[i].read(), TTWriter(&tte[i])};
 
     // Find an entry to be replaced according to the replacement strategy
     TTEntry* replace = tte;

From 2046c92ad461f5e852ba62a144b53c3d3fea04b0 Mon Sep 17 00:00:00 2001
From: FauziAkram <fauzi.dabat@hotmail.com>
Date: Wed, 12 Jun 2024 14:04:43 +0300
Subject: [PATCH 02/25] Tweak the reduction formula

Tweak the reduction formula if position is or has been on the PV
Taking inspiration from an old Viren test.

Passed STC:
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 78528 W: 20607 L: 20225 D: 37696
Ptnml(0-2): 262, 9297, 19785, 9637, 283
https://tests.stockfishchess.org/tests/view/666339c70ff7cb4868d1fe24

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 138630 W: 35666 L: 35132 D: 67832
Ptnml(0-2): 118, 15345, 37835, 15919, 98
https://tests.stockfishchess.org/tests/view/66645dec0612cd151f9e77b0

closes https://github.com/official-stockfish/Stockfish/pull/5385

Bench: 1134281
---
 src/search.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/search.cpp b/src/search.cpp
index af0ab400f..8fb65fe76 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1134,7 +1134,8 @@ moves_loop:  // When in check, search starts here
 
         // Decrease reduction if position is or has been on the PV (~7 Elo)
         if (ss->ttPv)
-            r -= 1 + (ttData.value > alpha) + (ttData.depth >= depth);
+            r -= 1 + (ttData.value > alpha) + (ttData.depth >= depth)
+               - (PvNode && ttData.value < alpha && ttData.depth >= depth);
 
         // Decrease reduction for PvNodes (~0 Elo on STC, ~2 Elo on LTC)
         if (PvNode)

From 2678606e8dbeac8332909f0b3e43638936570835 Mon Sep 17 00:00:00 2001
From: xoto10 <23479932+xoto10@users.noreply.github.com>
Date: Fri, 14 Jun 2024 17:27:09 +0100
Subject: [PATCH 03/25] Consider wider range of moves near leaves.

try to avoid missing good moves for opponent or engine, by updating bestMove
also when value == bestValue (i.e. value == alpha) under certain conditions.
In particular require this is at higher depth in the tree, leaving the logic
near the root unchanged, and only apply randomly. Avoid doing this near mate
scores, leaving mate PVs intact.

Passed SMP STC 6+0.06 th7 :
LLR: 2.94 (-2.94,2.94) <0.00,2.00>
Total: 42040 W: 10930 L: 10624 D: 20486
Ptnml(0-2): 28, 4682, 11289, 4998, 23
https://tests.stockfishchess.org/tests/view/66608b00c340c8eed7757d1d

Passed SMP LTC 24+0.24 th7 :
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 73692 W: 18978 L: 18600 D: 36114
Ptnml(0-2): 9, 7421, 21614, 7787, 15
https://tests.stockfishchess.org/tests/view/666095e8c340c8eed7757d49

closes https://github.com/official-stockfish/Stockfish/pull/5367

Bench 1205168
---
 src/search.cpp | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/search.cpp b/src/search.cpp
index 8fb65fe76..75eea2fd9 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1283,11 +1283,17 @@ moves_loop:  // When in check, search starts here
                 rm.score = -VALUE_INFINITE;
         }
 
-        if (value > bestValue)
+        // In case we have an alternative move equal in eval to the current bestmove,
+        // promote it to bestmove by pretending it just exceeds alpha (but not beta).
+        int inc = (value == bestValue && (int(nodes) & 15) == 0
+                   && ss->ply + 2 + ss->ply / 32 >= thisThread->rootDepth
+                   && std::abs(value) + 1 < VALUE_TB_WIN_IN_MAX_PLY);
+
+        if (value + inc > bestValue)
         {
             bestValue = value;
 
-            if (value > alpha)
+            if (value + inc > alpha)
             {
                 bestMove = move;
 

From 5514690f8e19631054271a6ca7e1cbfaf1b443f2 Mon Sep 17 00:00:00 2001
From: Joost VandeVondele <Joost.VandeVondele@gmail.com>
Date: Sat, 22 Jun 2024 09:17:45 +0200
Subject: [PATCH 04/25] CI/CD: play games

this action plays games under fast-chess with a `debug=yes` compiled binary.

It checks for triggered asserts in the code, or generally for engine disconnects.

closes https://github.com/official-stockfish/Stockfish/pull/5403

No functional change
---
 .github/workflows/games.yml     | 41 +++++++++++++++++++++++++++++++++
 .github/workflows/stockfish.yml |  2 ++
 2 files changed, 43 insertions(+)
 create mode 100644 .github/workflows/games.yml

diff --git a/.github/workflows/games.yml b/.github/workflows/games.yml
new file mode 100644
index 000000000..088695e57
--- /dev/null
+++ b/.github/workflows/games.yml
@@ -0,0 +1,41 @@
+# This workflow will play games with a debug enabled SF using the PR
+
+name: Games
+on:
+  workflow_call:
+jobs:
+  Matetrack:
+    name: Games
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Checkout SF repo 
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ github.event.pull_request.head.sha }}
+          path: Stockfish
+
+      - name: build debug enabled version of SF
+        working-directory: Stockfish/src
+        run: make -j build debug=yes
+
+      - name: Checkout fast-chess repo
+        uses: actions/checkout@v4
+        with:
+          repository: Disservin/fast-chess
+          path: fast-chess
+          ref: d54af1910d5479c669dc731f1f54f9108a251951
+
+      - name: fast-chess build
+        working-directory: fast-chess
+        run: make -j
+
+      - name: Run games
+        working-directory: fast-chess
+        run: |
+          ./fast-chess  -rounds 4 -games 2 -repeat -concurrency 4 -openings file=app/tests/data/openings.epd format=epd order=random -srand $RANDOM\
+               -engine name=sf1 cmd=/home/runner/work/Stockfish/Stockfish/Stockfish/src/stockfish\
+               -engine name=sf2 cmd=/home/runner/work/Stockfish/Stockfish/Stockfish/src/stockfish\
+               -ratinginterval 1 -report penta=true -each proto=uci tc=4+0.04 -log file=fast.log | tee fast.out
+          cat fast.log
+          ! grep "Assertion" fast.log > /dev/null
+          ! grep "disconnect" fast.out > /dev/null
diff --git a/.github/workflows/stockfish.yml b/.github/workflows/stockfish.yml
index fcaa3f6b8..8a1094fbd 100644
--- a/.github/workflows/stockfish.yml
+++ b/.github/workflows/stockfish.yml
@@ -92,6 +92,8 @@ jobs:
     uses: ./.github/workflows/tests.yml
   Matetrack:
     uses: ./.github/workflows/matetrack.yml
+  Games:
+    uses: ./.github/workflows/games.yml
   Binaries:
     if: github.repository == 'official-stockfish/Stockfish'
     needs: [Matrix, Prerelease, Compilation]

From 8806a58ebf5ade73696fd1f89ac4ea12cd1eedd3 Mon Sep 17 00:00:00 2001
From: evqsx <149484438+evqsx@users.noreply.github.com>
Date: Sun, 16 Jun 2024 12:34:24 +0800
Subject: [PATCH 05/25] Simplify static exchange evaluation pruning formula

Passed STC: https://tests.stockfishchess.org/tests/view/666bda31602682471b064e1f
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 141696 W: 36932 L: 36826 D: 67938
Ptnml(0-2): 510, 16880, 35989, 16932, 537

Passed LTC: https://tests.stockfishchess.org/tests/view/666e6b67602682471b064f4b
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 159504 W: 40552 L: 40471 D: 78481
Ptnml(0-2): 130, 18160, 43103, 18217, 142

closes https://github.com/official-stockfish/Stockfish/pull/5400

bench: 1084115
---
 src/search.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/search.cpp b/src/search.cpp
index 75eea2fd9..9b296e7fe 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1586,7 +1586,7 @@ Value Search::Worker::qsearch(Position& pos, Stack* ss, Value alpha, Value beta,
 
                 // If static exchange evaluation is much worse than what is needed to not
                 // fall below alpha we can prune this move.
-                if (futilityBase > alpha && !pos.see_ge(move, (alpha - futilityBase) * 2 - 30))
+                if (futilityBase > alpha && !pos.see_ge(move, (alpha - futilityBase) * 4))
                 {
                     bestValue = alpha;
                     continue;

From d5c130569b364899fc151101d069291a8934789a Mon Sep 17 00:00:00 2001
From: Shawn Xu <xu107288696@gmail.com>
Date: Sun, 16 Jun 2024 16:14:22 -0700
Subject: [PATCH 06/25] Simplify Bonus Formula In History Adjustment

Inspired by a discord message [1] from Vizvezdenec, this patch simplifies the
bonus adjustment bonus = bonus > 0 ? 2 * bonus : bonus / 2 to a constant
addition, maintaining bonus average at around 0 in regular bench. As cj5716
pointed in discord [2], the constant bonus can also be considered as factoring
tempo when calculating bonus, yielding a better value of the move.

[1] https://discord.com/channels/435943710472011776/882956631514689597/1243877089443188776
[2] https://discord.com/channels/435943710472011776/813919248455827515/1252277437249622077

Passed Non-regression STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 29984 W: 7908 L: 7677 D: 14399
Ptnml(0-2): 95, 3502, 7594, 3679, 122
https://tests.stockfishchess.org/tests/view/666f7210602682471b064fa2

Passed Non-regression LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 170136 W: 43214 L: 43145 D: 83777
Ptnml(0-2): 158, 19185, 46311, 19258, 156
https://tests.stockfishchess.org/tests/view/666fb32e602682471b064fb5

closes https://github.com/official-stockfish/Stockfish/pull/5401

bench 1438375
---
 src/search.cpp | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/search.cpp b/src/search.cpp
index 9b296e7fe..562bdbf9c 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -750,8 +750,7 @@ Value Search::Worker::search(
     // Use static evaluation difference to improve quiet move ordering (~9 Elo)
     if (((ss - 1)->currentMove).is_ok() && !(ss - 1)->inCheck && !priorCapture)
     {
-        int bonus = std::clamp(-10 * int((ss - 1)->staticEval + ss->staticEval), -1590, 1371);
-        bonus     = bonus > 0 ? 2 * bonus : bonus / 2;
+        int bonus = std::clamp(-10 * int((ss - 1)->staticEval + ss->staticEval), -1590, 1371) + 800;
         thisThread->mainHistory[~us][((ss - 1)->currentMove).from_to()] << bonus;
         if (type_of(pos.piece_on(prevSq)) != PAWN && ((ss - 1)->currentMove).type_of() != PROMOTION)
             thisThread->pawnHistory[pawn_structure_index(pos)][pos.piece_on(prevSq)][prevSq]

From cc992e5e4a7110b21f85168bdedad7978edad140 Mon Sep 17 00:00:00 2001
From: FauziAkram <fauzi.dabat@hotmail.com>
Date: Mon, 17 Jun 2024 00:03:15 +0300
Subject: [PATCH 07/25] Internal iterative reductions: decrease depth more

For PV nodes without a ttMove, we decrease depth.
But in this patch, additionally, if the current position is found in the TT, and the stored depth in the TT is greater than or equal to
the current search depth, we decrease the search depth even further.

Passed STC:
LLR: 2.96 (-2.94,2.94) <0.00,2.00>
Total: 84384 W: 22154 L: 21761 D: 40469
Ptnml(0-2): 292, 9972, 21315, 10277, 336
https://tests.stockfishchess.org/tests/view/666b0a4d602682471b064db6

Passed LTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 92106 W: 23471 L: 23032 D: 45603
Ptnml(0-2): 79, 10155, 25154, 10578, 87
https://tests.stockfishchess.org/tests/view/666c423d602682471b064e56

closes https://github.com/official-stockfish/Stockfish/pull/5397

bench: 1038234
---
 src/search.cpp | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/search.cpp b/src/search.cpp
index 562bdbf9c..e63595c1b 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -829,9 +829,12 @@ Value Search::Worker::search(
     }
 
     // Step 10. Internal iterative reductions (~9 Elo)
-    // For PV nodes without a ttMove, we decrease depth by 3.
+    // For PV nodes without a ttMove, we decrease depth.
+    // Additionally, if the current position is found in the TT
+    // and the stored depth in the TT is greater than or equal to
+    // current search depth, we decrease search depth even further.
     if (PvNode && !ttData.move)
-        depth -= 3;
+        depth -= 3 + (ss->ttHit && ttData.depth >= depth);
 
     // Use qsearch if depth <= 0.
     if (depth <= 0)

From 5fbfd06171cadf97e6e8173216046b099ebfa43b Mon Sep 17 00:00:00 2001
From: Joost VandeVondele <Joost.VandeVondele@gmail.com>
Date: Sun, 23 Jun 2024 21:53:25 +0200
Subject: [PATCH 08/25] Move info output afer uciok

fixes #5393 : an incompatibility with an older GUI (Chesspartner)
fixes #5396 : an incompatibility with an older GUI (Fritz9)

closes https://github.com/official-stockfish/Stockfish/pull/5404

No functional change
---
 src/uci.cpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/uci.cpp b/src/uci.cpp
index 4bc358d8a..3c9177ee3 100644
--- a/src/uci.cpp
+++ b/src/uci.cpp
@@ -108,10 +108,11 @@ void UCIEngine::loop() {
             sync_cout << "id name " << engine_info(true) << "\n"
                       << engine.get_options() << sync_endl;
 
+            sync_cout << "uciok" << sync_endl;
+
+            // keep info strings after uciok for old GUIs
             print_info_string(engine.numa_config_information_as_string());
             print_info_string(engine.thread_binding_information_as_string());
-
-            sync_cout << "uciok" << sync_endl;
         }
 
         else if (token == "setoption")

From b2a12917e2125fcd1e1c344165e840b0756201a8 Mon Sep 17 00:00:00 2001
From: FauziAkram <fauzi.dabat@hotmail.com>
Date: Mon, 24 Jun 2024 17:12:07 +0300
Subject: [PATCH 09/25] Remove redundant inline

constexpr implies inline anyway

closes https://github.com/official-stockfish/Stockfish/pull/5406

No functional change
---
 src/misc.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/misc.cpp b/src/misc.cpp
index e97d58b93..26dd3a289 100644
--- a/src/misc.cpp
+++ b/src/misc.cpp
@@ -281,7 +281,7 @@ template<size_t N>
 struct DebugInfo {
     std::atomic<int64_t> data[N] = {0};
 
-    constexpr inline std::atomic<int64_t>& operator[](int index) { return data[index]; }
+    constexpr std::atomic<int64_t>& operator[](int index) { return data[index]; }
 };
 
 DebugInfo<2> hit[MaxDebugSlots];

From 66e6274d32e9a59b6d0d8c347a0f1ee8175ffcdc Mon Sep 17 00:00:00 2001
From: Joost VandeVondele <Joost.VandeVondele@gmail.com>
Date: Mon, 1 Jul 2024 19:44:00 +0200
Subject: [PATCH 10/25] Fix typos in comments

closes https://github.com/official-stockfish/Stockfish/pull/5409

No functional change
---
 src/thread.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/thread.h b/src/thread.h
index 7416271b4..81ca39bbc 100644
--- a/src/thread.h
+++ b/src/thread.h
@@ -39,10 +39,10 @@ namespace Stockfish {
 class OptionsMap;
 using Value = int;
 
-// Sometimes we don't want to actually bind the threads, but the recipent still
+// Sometimes we don't want to actually bind the threads, but the recipient still
 // needs to think it runs on *some* NUMA node, such that it can access structures
 // that rely on NUMA node knowledge. This class encapsulates this optional process
-// such that the recipent does not need to know whether the binding happened or not.
+// such that the recipient does not need to know whether the binding happened or not.
 class OptionalThreadToNumaNodeBinder {
    public:
     OptionalThreadToNumaNodeBinder(NumaIndex n) :
@@ -87,7 +87,7 @@ class Thread {
     // this name is no longer correct. However, this class (and ThreadPool)
     // require further work to make them properly generic while maintaining
     // appropriate specificity regarding search, from the point of view of an
-    // outside user, so renaming of this function in left for whenever that happens.
+    // outside user, so renaming of this function is left for whenever that happens.
     void   wait_for_search_finished();
     size_t id() const { return idx; }
 

From 22a502ac7486576f52d7ba6cf884702162e92400 Mon Sep 17 00:00:00 2001
From: Taras Vuk <117687515+TarasVuk@users.noreply.github.com>
Date: Tue, 25 Jun 2024 10:48:50 +0200
Subject: [PATCH 11/25] Skip futility pruning if beta is below TB loss value

Passed STC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 77024 W: 20122 L: 19946 D: 36956
Ptnml(0-2): 278, 8754, 20277, 8920, 283
https://tests.stockfishchess.org/tests/view/66752d59602682471b0652f3

Passed LTC:
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 93114 W: 23623 L: 23477 D: 46014
Ptnml(0-2): 77, 9839, 26566, 10011, 64
https://tests.stockfishchess.org/tests/view/6676b3e1602682471b065395

closes https://github.com/official-stockfish/Stockfish/pull/5413

bench: 1003441
---
 src/search.cpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/search.cpp b/src/search.cpp
index e63595c1b..d04ba194d 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -784,8 +784,9 @@ Value Search::Worker::search(
         && eval - futility_margin(depth, cutNode && !ss->ttHit, improving, opponentWorsening)
                - (ss - 1)->statScore / 263
              >= beta
-        && eval >= beta && eval < VALUE_TB_WIN_IN_MAX_PLY && (!ttData.move || ttCapture))
-        return beta > VALUE_TB_LOSS_IN_MAX_PLY ? beta + (eval - beta) / 3 : eval;
+        && eval >= beta && (!ttData.move || ttCapture) && beta > VALUE_TB_LOSS_IN_MAX_PLY
+        && eval < VALUE_TB_WIN_IN_MAX_PLY)
+        return beta + (eval - beta) / 3;
 
     // Step 9. Null move search with verification search (~35 Elo)
     if (!PvNode && (ss - 1)->currentMove != Move::null() && (ss - 1)->statScore < 14369

From 90eca83e7f40ca719cd49e487893f32598ae6f19 Mon Sep 17 00:00:00 2001
From: mstembera <m_stembera@yahoo.com>
Date: Sat, 29 Jun 2024 17:18:39 -0700
Subject: [PATCH 12/25] Simplify away a useless TTEntry::read()

Not needed when we don hit an entry.

closes https://github.com/official-stockfish/Stockfish/pull/5416

No functional change
---
 src/tt.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/tt.cpp b/src/tt.cpp
index 30104ab7d..4b55e53fd 100644
--- a/src/tt.cpp
+++ b/src/tt.cpp
@@ -238,7 +238,7 @@ std::tuple<bool, TTData, TTWriter> TranspositionTable::probe(const Key key) cons
             > tte[i].depth8 - tte[i].relative_age(generation8) * 2)
             replace = &tte[i];
 
-    return {false, replace->read(), TTWriter(replace)};
+    return {false, TTData(), TTWriter(replace)};
 }
 
 

From 91ec31dac430e1d587f8239f2377ffb796008f8a Mon Sep 17 00:00:00 2001
From: Daniel Monroe <39802758+Ergodice@users.noreply.github.com>
Date: Sat, 29 Jun 2024 21:23:41 -0400
Subject: [PATCH 13/25] Grade countermove bonus for low statscores

Passed STC:
LLR: 2.96 (-2.94,2.94) <0.00,2.00>
Total: 338592 W: 88396 L: 87627 D: 162569
Ptnml(0-2): 1161, 40201, 85788, 41000, 1146
https://tests.stockfishchess.org/tests/view/6679d40c0c2db3fa2dcecbcc

Passed LTC:
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 83526 W: 21429 L: 21010 D: 41087
Ptnml(0-2): 54, 9173, 22913, 9546, 77
https://tests.stockfishchess.org/tests/view/667c5f2980450dba965911fc

closes https://github.com/official-stockfish/Stockfish/pull/5418

bench: 1489815
---
 src/search.cpp | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/search.cpp b/src/search.cpp
index d04ba194d..81bb9a06c 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1355,10 +1355,16 @@ moves_loop:  // When in check, search starts here
     // Bonus for prior countermove that caused the fail low
     else if (!priorCapture && prevSq != SQ_NONE)
     {
-        int bonus = (113 * (depth > 5) + 118 * (PvNode || cutNode)
-                     + 191 * ((ss - 1)->statScore < -14396) + 119 * ((ss - 1)->moveCount > 8)
+        int bonus = (113 * (depth > 5) + 118 * (PvNode || cutNode) + 119 * ((ss - 1)->moveCount > 8)
                      + 64 * (!ss->inCheck && bestValue <= ss->staticEval - 107)
                      + 147 * (!(ss - 1)->inCheck && bestValue <= -(ss - 1)->staticEval - 75));
+
+
+        // proportional to "how much damage we have to undo"
+        if ((ss - 1)->statScore < -8000)
+            bonus += std::clamp(-(ss - 1)->statScore / 100, 0, 250);
+
+
         update_continuation_histories(ss - 1, pos.piece_on(prevSq), prevSq,
                                       stat_bonus(depth) * bonus / 100);
         thisThread->mainHistory[~us][((ss - 1)->currentMove).from_to()]

From 7b49f9dd7091ce1d075ebdd16fff85ff1dba31fa Mon Sep 17 00:00:00 2001
From: Michael Chaly <Vizvezdenec@gmail.com>
Date: Sun, 30 Jun 2024 12:47:04 +0300
Subject: [PATCH 14/25] Tweak multicut

This patch is an original patch by author of Altair
(https://github.com/Alex2262/AltairChessEngine) chess engine.

It allows to produce more aggressive multicut compared to master by changing
condition it needs to fulfil and also returns bigger value.  Also has applied
matetrack fix on top.

Passed STC:
https://tests.stockfishchess.org/tests/view/667223ab602682471b0650e2
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 50048 W: 13200 L: 12860 D: 23988
Ptnml(0-2): 181, 5822, 12679, 6160, 182

Passed LTC:
https://tests.stockfishchess.org/tests/view/6672f777602682471b06515d
LLR: 2.97 (-2.94,2.94) <0.50,2.50>
Total: 706380 W: 179707 L: 177981 D: 348692
Ptnml(0-2): 656, 79250, 191665, 80950, 669

closes https://github.com/official-stockfish/Stockfish/pull/5421

bench 1148966
---
 src/search.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/search.cpp b/src/search.cpp
index 81bb9a06c..da01f82f5 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1087,8 +1087,8 @@ moves_loop:  // When in check, search starts here
                 // and if after excluding the ttMove with a reduced search we fail high over the original beta,
                 // we assume this expected cut-node is not singular (multiple moves fail high),
                 // and we can prune the whole subtree by returning a softbound.
-                else if (singularBeta >= beta)
-                    return singularBeta;
+                else if (value >= beta && std::abs(value) < VALUE_TB_WIN_IN_MAX_PLY)
+                    return value;
 
                 // Negative extensions
                 // If other moves failed high over (ttValue - margin) without the ttMove on a reduced search,

From 38c5fc33e493f210dc199dab7c105e84e7601b99 Mon Sep 17 00:00:00 2001
From: "Shahin M. Shahin" <peregrineshahin@gmail.com>
Date: Sun, 30 Jun 2024 16:32:20 +0300
Subject: [PATCH 15/25] Increase reduction based on correct expectation

If the current node is not a cutNode then it means that the child is one in LMR
and the cutoff count is expected, so more reduction when the cutoffs are
expected

Passed STC:
https://tests.stockfishchess.org/tests/view/66815e791c5b344a34ca7090
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 64416 W: 16876 L: 16519 D: 31021
Ptnml(0-2): 150, 7670, 16264, 7921, 203

Passed LTC:
https://tests.stockfishchess.org/tests/view/668162f61c5b344a34ca725c
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 78186 W: 19905 L: 19499 D: 38782
Ptnml(0-2): 55, 8561, 21437, 9003, 37

closes https://github.com/official-stockfish/Stockfish/pull/5422

bench: 1161531
---
 src/search.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/search.cpp b/src/search.cpp
index da01f82f5..b68b30268 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1157,7 +1157,7 @@ moves_loop:  // When in check, search starts here
 
         // Increase reduction if next ply has a lot of fail high (~5 Elo)
         if ((ss + 1)->cutoffCnt > 3)
-            r++;
+            r += 1 + !(PvNode || cutNode);
 
         // For first picked move (ttMove) reduce reduction
         // but never allow it to go below 0 (~3 Elo)

From 5deb26239340a6a1a91d1c2050f90b7a36f9f5d1 Mon Sep 17 00:00:00 2001
From: FauziAkram <fauzi.dabat@hotmail.com>
Date: Sun, 30 Jun 2024 22:24:28 +0300
Subject: [PATCH 16/25] Simplify rm.averageScore calculation

Passed STC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 485056 W: 125222 L: 125497 D: 234337
Ptnml(0-2): 1384, 58197, 123614, 57976, 1357
https://tests.stockfishchess.org/tests/view/6681816d442423e54714133f

Passed LTC:
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 56622 W: 14301 L: 14115 D: 28206
Ptnml(0-2): 31, 6259, 15538, 6459, 24
https://tests.stockfishchess.org/tests/view/6681a9a5596d543edc677490

closes https://github.com/official-stockfish/Stockfish/pull/5423

bench: 1171203
---
 src/search.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/search.cpp b/src/search.cpp
index b68b30268..f561b1832 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1246,7 +1246,7 @@ moves_loop:  // When in check, search starts here
             rm.effort += nodes - nodeCount;
 
             rm.averageScore =
-              rm.averageScore != -VALUE_INFINITE ? (2 * value + rm.averageScore) / 3 : value;
+              rm.averageScore != -VALUE_INFINITE ? (value + rm.averageScore) / 2 : value;
 
             // PV move or new best move?
             if (moveCount == 1 || value > alpha)

From f6842a145cf59176abc229928b94404543daa250 Mon Sep 17 00:00:00 2001
From: Linmiao Xu <linmiao.xu@gmail.com>
Date: Sun, 30 Jun 2024 11:43:36 -0400
Subject: [PATCH 17/25] Simplify worsening deduction in futility margin

Passed non-regression STC:
https://tests.stockfishchess.org/tests/view/66817d46442423e547141226
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 345408 W: 89146 L: 89266 D: 166996
Ptnml(0-2): 954, 41317, 88286, 41189, 958

Passed non-regression LTC:
https://tests.stockfishchess.org/tests/view/66818dbe1e90a146232d1f62
LLR: 2.95 (-2.94,2.94) <-1.75,0.25>
Total: 173214 W: 43821 L: 43755 D: 85638
Ptnml(0-2): 108, 19407, 47492, 19511, 89

closes https://github.com/official-stockfish/Stockfish/pull/5424

bench 981017
---
 src/search.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/search.cpp b/src/search.cpp
index f561b1832..52eefdc94 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -62,7 +62,7 @@ static constexpr double EvalLevel[10] = {0.981, 0.956, 0.895, 0.949, 0.913,
 Value futility_margin(Depth d, bool noTtCutNode, bool improving, bool oppWorsening) {
     Value futilityMult       = 109 - 40 * noTtCutNode;
     Value improvingDeduction = 59 * improving * futilityMult / 32;
-    Value worseningDeduction = 328 * oppWorsening * futilityMult / 1024;
+    Value worseningDeduction = oppWorsening * futilityMult / 3;
 
     return futilityMult * d - improvingDeduction - worseningDeduction;
 }

From 843b6f7c9873d86742cf9b6ce3523f2c5dc69d2a Mon Sep 17 00:00:00 2001
From: Linmiao Xu <linmiao.xu@gmail.com>
Date: Sun, 30 Jun 2024 17:00:49 -0400
Subject: [PATCH 18/25] Update some params for pruning at shallow depth

Values found around 82k / 120k spsa games at 60+0.6:
https://tests.stockfishchess.org/tests/view/6681aca4481148df247298bd

Passed STC:
https://tests.stockfishchess.org/tests/view/6681c795c1657e386d2948fa
LLR: 2.93 (-2.94,2.94) <0.00,2.00>
Total: 145216 W: 37595 L: 37122 D: 70499
Ptnml(0-2): 375, 17122, 37185, 17507, 419

Passed LTC:
https://tests.stockfishchess.org/tests/view/6681d4eec1657e386d2949e0
LLR: 2.95 (-2.94,2.94) <0.50,2.50>
Total: 154062 W: 39117 L: 38557 D: 76388
Ptnml(0-2): 67, 16874, 42608, 17396, 86

closes https://github.com/official-stockfish/Stockfish/pull/5425

bench 996419
---
 src/search.cpp | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/search.cpp b/src/search.cpp
index 52eefdc94..2e8d47cf9 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -994,7 +994,7 @@ moves_loop:  // When in check, search starts here
                 // Futility pruning for captures (~2 Elo)
                 if (!givesCheck && lmrDepth < 7 && !ss->inCheck)
                 {
-                    Value futilityValue = ss->staticEval + 287 + 248 * lmrDepth
+                    Value futilityValue = ss->staticEval + 294 + 246 * lmrDepth
                                         + PieceValue[capturedPiece] + captHist / 7;
                     if (futilityValue <= alpha)
                         continue;
@@ -1002,7 +1002,7 @@ moves_loop:  // When in check, search starts here
 
                 // SEE based pruning for captures and checks (~11 Elo)
                 int seeHist = std::clamp(captHist / 32, -180 * depth, 163 * depth);
-                if (!pos.see_ge(move, -160 * depth - seeHist))
+                if (!pos.see_ge(move, -163 * depth - seeHist))
                     continue;
             }
             else
@@ -1013,15 +1013,15 @@ moves_loop:  // When in check, search starts here
                   + thisThread->pawnHistory[pawn_structure_index(pos)][movedPiece][move.to_sq()];
 
                 // Continuation history based pruning (~2 Elo)
-                if (lmrDepth < 6 && history < -4151 * depth)
+                if (lmrDepth < 6 && history < -3899 * depth)
                     continue;
 
                 history += 2 * thisThread->mainHistory[us][move.from_to()];
 
-                lmrDepth += history / 3678;
+                lmrDepth += history / 4040;
 
                 Value futilityValue =
-                  ss->staticEval + (bestValue < ss->staticEval - 51 ? 138 : 54) + 140 * lmrDepth;
+                  ss->staticEval + (bestValue < ss->staticEval - 51 ? 135 : 56) + 140 * lmrDepth;
 
                 // Futility pruning: parent node (~13 Elo)
                 if (!ss->inCheck && lmrDepth < 12 && futilityValue <= alpha)

From 6138a0fd0e43753a86e4a170a5f6e2b7b6752677 Mon Sep 17 00:00:00 2001
From: Dubslow <bunslow@gmail.com>
Date: Sun, 30 Jun 2024 19:22:04 -0400
Subject: [PATCH 19/25] Probcut in check no matter if pv or capture

Passed STC: https://tests.stockfishchess.org/tests/view/6681e9c8c1657e386d294cef
LLR: 2.93 (-2.94,2.94) <-1.75,0.25>
Total: 217824 W: 56149 L: 56129 D: 105546
Ptnml(0-2): 587, 25926, 55848, 25982, 569

Passed LTC: https://tests.stockfishchess.org/tests/view/6681fcb8c1657e386d294db1
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 357552 W: 90546 L: 90671 D: 176335
Ptnml(0-2): 207, 40064, 98362, 39933, 210

Each half of this also passed STC+LTC separately

closes https://github.com/official-stockfish/Stockfish/pull/5427

bench 1227870
---
 src/search.cpp | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/search.cpp b/src/search.cpp
index 2e8d47cf9..31278241c 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -906,9 +906,8 @@ moves_loop:  // When in check, search starts here
 
     // Step 12. A small Probcut idea, when we are in check (~4 Elo)
     probCutBeta = beta + 388;
-    if (ss->inCheck && !PvNode && ttCapture && (ttData.bound & BOUND_LOWER)
-        && ttData.depth >= depth - 4 && ttData.value >= probCutBeta
-        && std::abs(ttData.value) < VALUE_TB_WIN_IN_MAX_PLY
+    if (ss->inCheck && (ttData.bound & BOUND_LOWER) && ttData.depth >= depth - 4
+        && ttData.value >= probCutBeta && std::abs(ttData.value) < VALUE_TB_WIN_IN_MAX_PLY
         && std::abs(beta) < VALUE_TB_WIN_IN_MAX_PLY)
         return probCutBeta;
 

From 69ad4667fb40cc0d7195f9fa20652903813d698c Mon Sep 17 00:00:00 2001
From: Shawn Xu <xu107288696@gmail.com>
Date: Sun, 30 Jun 2024 22:04:51 -0700
Subject: [PATCH 20/25] Do Capture History Updates In Probcut

This patch introduces history updates to probcut. Standard depth - 3 bonus and
maluses are given to the capture that caused fail high and previously searched
captures, respectively. Similar to #5243, a negative history fill is applied to
compensate for an increase in capture history average, thus improving the
scaling of this patch.

Passed STC:
LLR: 2.95 (-2.94,2.94) <0.00,2.00>
Total: 84832 W: 21941 L: 21556 D: 41335
Ptnml(0-2): 226, 9927, 21688, 10386, 189
https://tests.stockfishchess.org/tests/view/6682fab9389b9ee542b1d029

Passed LTC:
LLR: 2.94 (-2.94,2.94) <0.50,2.50>
Total: 104298 W: 26469 L: 26011 D: 51818
Ptnml(0-2): 43, 11458, 28677, 11940, 31
https://tests.stockfishchess.org/tests/view/6682ff06389b9ee542b1d0a0

closes https://github.com/official-stockfish/Stockfish/pull/5428

bench 1281351
---
 src/search.cpp | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/src/search.cpp b/src/search.cpp
index 31278241c..188e81f4f 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -502,7 +502,7 @@ void Search::Worker::iterative_deepening() {
 void Search::Worker::clear() {
     counterMoves.fill(Move::none());
     mainHistory.fill(0);
-    captureHistory.fill(0);
+    captureHistory.fill(-700);
     pawnHistory.fill(-1193);
     correctionHistory.fill(0);
 
@@ -862,12 +862,19 @@ Value Search::Worker::search(
         assert(probCutBeta < VALUE_INFINITE && probCutBeta > beta);
 
         MovePicker mp(pos, ttData.move, probCutBeta - ss->staticEval, &thisThread->captureHistory);
+        Move       probcutCapturesSearched[32];
+        int        probcutCaptureCount = 0;
+        Piece      captured;
 
         while ((move = mp.next_move()) != Move::none())
             if (move != excludedMove && pos.legal(move))
             {
                 assert(pos.capture_stage(move));
 
+                movedPiece = pos.moved_piece(move);
+                captured   = pos.piece_on(move.to_sq());
+
+
                 // Prefetch the TT entry for the resulting position
                 prefetch(tt.first_entry(pos.key_after(move)));
 
@@ -891,12 +898,28 @@ Value Search::Worker::search(
 
                 if (value >= probCutBeta)
                 {
+                    thisThread->captureHistory[movedPiece][move.to_sq()][type_of(captured)]
+                      << stat_bonus(depth - 2);
+
+                    for (int i = 0; i < probcutCaptureCount; i++)
+                    {
+                        movedPiece = pos.moved_piece(probcutCapturesSearched[i]);
+                        captured   = pos.piece_on(probcutCapturesSearched[i].to_sq());
+
+                        thisThread->captureHistory[movedPiece][probcutCapturesSearched[i].to_sq()]
+                                                  [type_of(captured)]
+                          << -stat_malus(depth - 3);
+                    }
+
                     // Save ProbCut data into transposition table
                     ttWriter.write(posKey, value_to_tt(value, ss->ply), ss->ttPv, BOUND_LOWER,
                                    depth - 3, move, unadjustedStaticEval, tt.generation());
                     return std::abs(value) < VALUE_TB_WIN_IN_MAX_PLY ? value - (probCutBeta - beta)
                                                                      : value;
                 }
+
+                if (probcutCaptureCount < 32)
+                    probcutCapturesSearched[probcutCaptureCount++] = move;
             }
 
         Eval::NNUE::hint_common_parent_position(pos, networks[numaAccessToken], refreshTable);

From 6b7822119feffd0a27ae5b2a95d3570c9e046090 Mon Sep 17 00:00:00 2001
From: "Shahin M. Shahin" <peregrineshahin@gmail.com>
Date: Tue, 25 Jun 2024 01:57:35 +0300
Subject: [PATCH 21/25] Limit has_game_cycle() to only upcoming repetition

use the original algorithm according to the paper
http://web.archive.org/web/20201107002606/https://marcelk.net/2013-04-06/paper/upcoming-rep-v2.pdf,
which detects accurately if a position has an upcoming repetition. The 'no
progress' part of has_game_cycle has been removed, the function has been
renamed to upcoming_repetition to reflect this.

As a result of this fix, to the best of our knowledge, all PVs for completed
iterations that yield a mate or decisive table base score now end in mate or
contain a TB position, respectively.

passed non-regression STC:
https://tests.stockfishchess.org/tests/view/6679fa1d0c2db3fa2dcecbf2
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 63584 W: 16666 L: 16472 D: 30446
Ptnml(0-2): 186, 7552, 16146, 7698, 210

Passed non-regression LTC:
https://tests.stockfishchess.org/tests/view/667ac965e439ed1c7a9ca042
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 464574 W: 117493 L: 117729 D: 229352
Ptnml(0-2): 311, 52468, 126974, 52214, 320

closes https://github.com/official-stockfish/Stockfish/pull/5432

bench: 1209805
---
 src/position.cpp | 20 ++++++++++----------
 src/position.h   |  2 +-
 src/search.cpp   | 10 ++++------
 3 files changed, 15 insertions(+), 17 deletions(-)

diff --git a/src/position.cpp b/src/position.cpp
index b46ba0299..d374b1c07 100644
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -1156,9 +1156,9 @@ bool Position::has_repeated() const {
 }
 
 
-// Tests if the position has a move which draws by repetition,
-// or an earlier position has a move that directly reaches the current position.
-bool Position::has_game_cycle(int ply) const {
+// Tests if the position has a move which draws by repetition.
+// This function accurately matches the outcome of is_draw() over all legal moves.
+bool Position::upcoming_repetition(int ply) const {
 
     int j;
 
@@ -1169,10 +1169,16 @@ bool Position::has_game_cycle(int ply) const {
 
     Key        originalKey = st->key;
     StateInfo* stp         = st->previous;
+    Key        other       = originalKey ^ stp->key ^ Zobrist::side;
 
     for (int i = 3; i <= end; i += 2)
     {
-        stp = stp->previous->previous;
+        stp = stp->previous;
+        other ^= stp->key ^ stp->previous->key ^ Zobrist::side;
+        stp = stp->previous;
+
+        if (other != 0)
+            continue;
 
         Key moveKey = originalKey ^ stp->key;
         if ((j = H1(moveKey), cuckoo[j] == moveKey) || (j = H2(moveKey), cuckoo[j] == moveKey))
@@ -1188,12 +1194,6 @@ bool Position::has_game_cycle(int ply) const {
 
                 // For nodes before or at the root, check that the move is a
                 // repetition rather than a move to the current position.
-                // In the cuckoo table, both moves Rc1c5 and Rc5c1 are stored in
-                // the same location, so we have to select which square to check.
-                if (color_of(piece_on(empty(s1) ? s2 : s1)) != side_to_move())
-                    continue;
-
-                // For repetitions before or at the root, require one more
                 if (stp->repetition)
                     return true;
             }
diff --git a/src/position.h b/src/position.h
index 154ed6529..3cfb87d06 100644
--- a/src/position.h
+++ b/src/position.h
@@ -156,7 +156,7 @@ class Position {
     int   game_ply() const;
     bool  is_chess960() const;
     bool  is_draw(int ply) const;
-    bool  has_game_cycle(int ply) const;
+    bool  upcoming_repetition(int ply) const;
     bool  has_repeated() const;
     int   rule50_count() const;
     Value non_pawn_material(Color c) const;
diff --git a/src/search.cpp b/src/search.cpp
index 188e81f4f..6368acc6b 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -534,9 +534,8 @@ Value Search::Worker::search(
     // Limit the depth if extensions made it too large
     depth = std::min(depth, MAX_PLY - 1);
 
-    // Check if we have an upcoming move that draws by repetition, or
-    // if the opponent had an alternative move earlier to this position.
-    if (!rootNode && alpha < VALUE_DRAW && pos.has_game_cycle(ss->ply))
+    // Check if we have an upcoming move that draws by repetition.
+    if (!rootNode && alpha < VALUE_DRAW && pos.upcoming_repetition(ss->ply))
     {
         alpha = value_draw(this->nodes);
         if (alpha >= beta)
@@ -1447,9 +1446,8 @@ Value Search::Worker::qsearch(Position& pos, Stack* ss, Value alpha, Value beta,
     assert(PvNode || (alpha == beta - 1));
     assert(depth <= 0);
 
-    // Check if we have an upcoming move that draws by repetition, or if
-    // the opponent had an alternative move earlier to this position. (~1 Elo)
-    if (alpha < VALUE_DRAW && pos.has_game_cycle(ss->ply))
+    // Check if we have an upcoming move that draws by repetition. (~1 Elo)
+    if (alpha < VALUE_DRAW && pos.upcoming_repetition(ss->ply))
     {
         alpha = value_draw(this->nodes);
         if (alpha >= beta)

From ad0f1fecda6987b16e34807a5ebc3947ced9a866 Mon Sep 17 00:00:00 2001
From: Joost VandeVondele <Joost.VandeVondele@gmail.com>
Date: Tue, 2 Jul 2024 14:18:04 +0200
Subject: [PATCH 22/25] Move info strings once more

Follow up from #5404 ... current location leads to troubles with Aquarium GUI

Fixes #5430

Now prints the information on threads and available processors at the beginning
of search, where info about the networks is already printed (and is known to
work)

closes https://github.com/official-stockfish/Stockfish/pull/5433

No functional change.
---
 src/engine.cpp | 16 ++++++++++------
 src/uci.cpp    |  9 +++++----
 2 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/src/engine.cpp b/src/engine.cpp
index 233f62701..2bc0db6af 100644
--- a/src/engine.cpp
+++ b/src/engine.cpp
@@ -297,16 +297,20 @@ std::string Engine::get_numa_config_as_string() const {
 
 std::string Engine::numa_config_information_as_string() const {
     auto cfgStr = get_numa_config_as_string();
-    return "Available Processors: " + cfgStr;
+    return "Available processors: " + cfgStr;
 }
 
 std::string Engine::thread_binding_information_as_string() const {
-    auto boundThreadsByNode = get_bound_thread_count_by_numa_node();
-    if (boundThreadsByNode.empty())
-        return "";
-
+    auto              boundThreadsByNode = get_bound_thread_count_by_numa_node();
     std::stringstream ss;
-    ss << "NUMA Node Thread Binding: ";
+
+    size_t threadsSize = threads.size();
+    ss << "Using " << threadsSize << (threadsSize > 1 ? " threads" : " thread");
+
+    if (boundThreadsByNode.empty())
+        return ss.str();
+
+    ss << " with NUMA node thread binding: ";
 
     bool isFirst = true;
 
diff --git a/src/uci.cpp b/src/uci.cpp
index 3c9177ee3..9b60680d8 100644
--- a/src/uci.cpp
+++ b/src/uci.cpp
@@ -109,16 +109,17 @@ void UCIEngine::loop() {
                       << engine.get_options() << sync_endl;
 
             sync_cout << "uciok" << sync_endl;
-
-            // keep info strings after uciok for old GUIs
-            print_info_string(engine.numa_config_information_as_string());
-            print_info_string(engine.thread_binding_information_as_string());
         }
 
         else if (token == "setoption")
             setoption(is);
         else if (token == "go")
+        {
+            // send info strings after the go command is sent for old GUIs and python-chess
+            print_info_string(engine.numa_config_information_as_string());
+            print_info_string(engine.thread_binding_information_as_string());
             go(is);
+        }
         else if (token == "position")
             position(is);
         else if (token == "ucinewgame")

From b9ff5bb93be410b418d6812d6753e64cf216057a Mon Sep 17 00:00:00 2001
From: Shawn Xu <xu107288696@gmail.com>
Date: Tue, 2 Jul 2024 15:06:37 -0700
Subject: [PATCH 23/25] Implement dbg_extremes_of

An alternative to #5431, implements one function `dbg_extremes_of` to keep track
of min and max.

closes https://github.com/official-stockfish/Stockfish/pull/5434

No functional change
---
 src/misc.cpp | 35 +++++++++++++++++++++++++++++++----
 src/misc.h   |  2 ++
 2 files changed, 33 insertions(+), 4 deletions(-)

diff --git a/src/misc.cpp b/src/misc.cpp
index 26dd3a289..b68c12b97 100644
--- a/src/misc.cpp
+++ b/src/misc.cpp
@@ -284,10 +284,18 @@ struct DebugInfo {
     constexpr std::atomic<int64_t>& operator[](int index) { return data[index]; }
 };
 
-DebugInfo<2> hit[MaxDebugSlots];
-DebugInfo<2> mean[MaxDebugSlots];
-DebugInfo<3> stdev[MaxDebugSlots];
-DebugInfo<6> correl[MaxDebugSlots];
+struct DebugExtremes: public DebugInfo<3> {
+    DebugExtremes() {
+        data[1] = std::numeric_limits<int64_t>::min();
+        data[2] = std::numeric_limits<int64_t>::max();
+    }
+};
+
+DebugInfo<2>  hit[MaxDebugSlots];
+DebugInfo<2>  mean[MaxDebugSlots];
+DebugInfo<3>  stdev[MaxDebugSlots];
+DebugInfo<6>  correl[MaxDebugSlots];
+DebugExtremes extremes[MaxDebugSlots];
 
 }  // namespace
 
@@ -311,6 +319,18 @@ void dbg_stdev_of(int64_t value, int slot) {
     stdev[slot][2] += value * value;
 }
 
+void dbg_extremes_of(int64_t value, int slot) {
+    ++extremes[slot][0];
+
+    int64_t current_max = extremes[slot][1].load();
+    while (current_max < value && !extremes[slot][1].compare_exchange_weak(current_max, value))
+    {}
+
+    int64_t current_min = extremes[slot][2].load();
+    while (current_min > value && !extremes[slot][2].compare_exchange_weak(current_min, value))
+    {}
+}
+
 void dbg_correl_of(int64_t value1, int64_t value2, int slot) {
 
     ++correl[slot][0];
@@ -345,6 +365,13 @@ void dbg_print() {
             std::cerr << "Stdev #" << i << ": Total " << n << " Stdev " << r << std::endl;
         }
 
+    for (int i = 0; i < MaxDebugSlots; ++i)
+        if ((n = extremes[i][0]))
+        {
+            std::cerr << "Extremity #" << i << ": Total " << n << " Min " << extremes[i][2]
+                      << " Max " << extremes[i][1] << std::endl;
+        }
+
     for (int i = 0; i < MaxDebugSlots; ++i)
         if ((n = correl[i][0]))
         {
diff --git a/src/misc.h b/src/misc.h
index bdc7c864d..0184ab88c 100644
--- a/src/misc.h
+++ b/src/misc.h
@@ -67,6 +67,8 @@ std::optional<std::string> read_file_to_string(const std::string& path);
 void dbg_hit_on(bool cond, int slot = 0);
 void dbg_mean_of(int64_t value, int slot = 0);
 void dbg_stdev_of(int64_t value, int slot = 0);
+void dbg_extremes_of(int64_t value, int slot);
+
 void dbg_correl_of(int64_t value1, int64_t value2, int slot = 0);
 void dbg_print();
 

From ee6fc7e38b4aeef44862159215a56d97122f59a0 Mon Sep 17 00:00:00 2001
From: Joost VandeVondele <Joost.VandeVondele@gmail.com>
Date: Wed, 3 Jul 2024 11:14:41 +0200
Subject: [PATCH 24/25] CI: limit artifact uploads

do not upload some unneeded intermediate directories,
disable running authenticated git commands with the checkout action.

Thanks to Yaron A for the report.

closes https://github.com/official-stockfish/Stockfish/pull/5435

No functional change
---
 .github/workflows/arm_compilation.yml | 6 +++++-
 .github/workflows/clang-format.yml    | 1 +
 .github/workflows/codeql.yml          | 2 ++
 .github/workflows/compilation.yml     | 7 ++++++-
 .github/workflows/games.yml           | 2 ++
 .github/workflows/iwyu.yml            | 2 ++
 .github/workflows/matetrack.yml       | 2 ++
 .github/workflows/sanitizers.yml      | 2 ++
 .github/workflows/stockfish.yml       | 4 ++++
 .github/workflows/tests.yml           | 1 +
 .github/workflows/upload_binaries.yml | 2 ++
 11 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/.github/workflows/arm_compilation.yml b/.github/workflows/arm_compilation.yml
index 3934ac2d6..5bf2a93e5 100644
--- a/.github/workflows/arm_compilation.yml
+++ b/.github/workflows/arm_compilation.yml
@@ -26,6 +26,7 @@ jobs:
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0
+          persist-credentials: false
 
       - name: Download required linux packages
         if: runner.os == 'Linux'
@@ -91,4 +92,7 @@ jobs:
         uses: actions/upload-artifact@v4
         with:
           name: ${{ matrix.config.simple_name }} ${{ matrix.binaries }}
-          path: .
+          path: |
+            .
+            !.git
+            !.output
diff --git a/.github/workflows/clang-format.yml b/.github/workflows/clang-format.yml
index 630edbf93..637cfc0d8 100644
--- a/.github/workflows/clang-format.yml
+++ b/.github/workflows/clang-format.yml
@@ -19,6 +19,7 @@ jobs:
       - uses: actions/checkout@v4
         with:
           ref: ${{ github.event.pull_request.head.sha }}
+          persist-credentials: false
 
       - name: Run clang-format style check
         uses: jidicula/clang-format-action@f62da5e3d3a2d88ff364771d9d938773a618ab5e # @v4.11.0
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index d949a5a76..d01ed41fe 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -30,6 +30,8 @@ jobs:
     steps:
       - name: Checkout repository
         uses: actions/checkout@v4
+        with:
+          persist-credentials: false
 
       # Initializes the CodeQL tools for scanning.
       - name: Initialize CodeQL
diff --git a/.github/workflows/compilation.yml b/.github/workflows/compilation.yml
index 3524d5e9f..5878adecb 100644
--- a/.github/workflows/compilation.yml
+++ b/.github/workflows/compilation.yml
@@ -25,6 +25,8 @@ jobs:
         shell: ${{ matrix.config.shell }}
     steps:
       - uses: actions/checkout@v4
+        with:
+          persist-credentials: false
 
       - name: Install fixed GCC on Linux
         if: runner.os == 'Linux'
@@ -86,4 +88,7 @@ jobs:
         uses: actions/upload-artifact@v4
         with:
           name: ${{ matrix.config.simple_name }} ${{ matrix.binaries }}
-          path: .
+          path: |
+             .
+             !.git
+             !.output
diff --git a/.github/workflows/games.yml b/.github/workflows/games.yml
index 088695e57..f0bca442f 100644
--- a/.github/workflows/games.yml
+++ b/.github/workflows/games.yml
@@ -13,6 +13,7 @@ jobs:
         with:
           ref: ${{ github.event.pull_request.head.sha }}
           path: Stockfish
+          persist-credentials: false
 
       - name: build debug enabled version of SF
         working-directory: Stockfish/src
@@ -24,6 +25,7 @@ jobs:
           repository: Disservin/fast-chess
           path: fast-chess
           ref: d54af1910d5479c669dc731f1f54f9108a251951
+          persist-credentials: false
 
       - name: fast-chess build
         working-directory: fast-chess
diff --git a/.github/workflows/iwyu.yml b/.github/workflows/iwyu.yml
index 0552a598c..f8898b1c9 100644
--- a/.github/workflows/iwyu.yml
+++ b/.github/workflows/iwyu.yml
@@ -14,6 +14,7 @@ jobs:
         uses: actions/checkout@v4
         with:
           path: Stockfish
+          persist-credentials: false
 
       - name: Checkout include-what-you-use
         uses: actions/checkout@v4
@@ -21,6 +22,7 @@ jobs:
           repository: include-what-you-use/include-what-you-use
           ref: f25caa280dc3277c4086ec345ad279a2463fea0f
           path: include-what-you-use
+          persist-credentials: false
 
       - name: Download required linux packages
         run: |
diff --git a/.github/workflows/matetrack.yml b/.github/workflows/matetrack.yml
index dd81f334d..de65209fb 100644
--- a/.github/workflows/matetrack.yml
+++ b/.github/workflows/matetrack.yml
@@ -13,6 +13,7 @@ jobs:
         with:
           ref: ${{ github.event.pull_request.head.sha }}
           path: Stockfish
+          persist-credentials: false
 
       - name: build SF
         working-directory: Stockfish/src
@@ -24,6 +25,7 @@ jobs:
           repository: vondele/matetrack
           path: matetrack
           ref: 20287a1a145f30a166b7ef251eddb611e4e44fbf
+          persist-credentials: false
 
       - name: matetrack install deps
         working-directory: matetrack
diff --git a/.github/workflows/sanitizers.yml b/.github/workflows/sanitizers.yml
index b75c06cfb..554592921 100644
--- a/.github/workflows/sanitizers.yml
+++ b/.github/workflows/sanitizers.yml
@@ -40,6 +40,8 @@ jobs:
         shell: ${{ matrix.config.shell }}
     steps:
       - uses: actions/checkout@v4
+        with:
+          persist-credentials: false
 
       - name: Download required linux packages
         run: |
diff --git a/.github/workflows/stockfish.yml b/.github/workflows/stockfish.yml
index 8a1094fbd..5589c7624 100644
--- a/.github/workflows/stockfish.yml
+++ b/.github/workflows/stockfish.yml
@@ -17,6 +17,8 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+        with:
+          persist-credentials: false
 
       # returns null if no pre-release exists
       - name: Get Commit SHA of Latest Pre-release
@@ -66,6 +68,8 @@ jobs:
       arm_matrix: ${{ steps.set-arm-matrix.outputs.arm_matrix }}
     steps:
       - uses: actions/checkout@v4
+        with:
+          persist-credentials: false
       - id: set-matrix
         run: |
           TASKS=$(echo $(cat .github/ci/matrix.json) )
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 328c9cf94..836555e61 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -106,6 +106,7 @@ jobs:
       - uses: actions/checkout@v4
         with:
           fetch-depth: 0
+          persist-credentials: false
 
       - name: Download required linux packages
         if: runner.os == 'Linux'
diff --git a/.github/workflows/upload_binaries.yml b/.github/workflows/upload_binaries.yml
index acf91a8f3..c91824a25 100644
--- a/.github/workflows/upload_binaries.yml
+++ b/.github/workflows/upload_binaries.yml
@@ -25,6 +25,8 @@ jobs:
         shell: ${{ matrix.config.shell }}
     steps:
       - uses: actions/checkout@v4
+        with:
+          persist-credentials: false
 
       - name: Download artifact from compilation
         uses: actions/download-artifact@v4

From 74a8fc060465a822f0c047f908d5fb07ebc6ad96 Mon Sep 17 00:00:00 2001
From: Disservin <disservin.social@gmail.com>
Date: Wed, 3 Jul 2024 14:07:48 +0200
Subject: [PATCH 25/25] Use explicit action permissions in CI

Necessary modifications according to changes in the GitHub Action settings.

closes https://github.com/official-stockfish/Stockfish/pull/5437

Follow up from the report by Yaron Avital (yaronav) earlier.

No functional change
---
 .github/workflows/stockfish.yml       | 10 ++++++++++
 .github/workflows/upload_binaries.yml |  5 +++++
 2 files changed, 15 insertions(+)

diff --git a/.github/workflows/stockfish.yml b/.github/workflows/stockfish.yml
index 5589c7624..1f87e061b 100644
--- a/.github/workflows/stockfish.yml
+++ b/.github/workflows/stockfish.yml
@@ -15,6 +15,8 @@ jobs:
   Prerelease:
     if: github.repository == 'official-stockfish/Stockfish' && (github.ref == 'refs/heads/master' || (startsWith(github.ref_name, 'sf_') && github.ref_type == 'tag'))
     runs-on: ubuntu-latest
+    permissions:
+      contents: write # For deleting/creating a prerelease
     steps:
       - uses: actions/checkout@v4
         with:
@@ -104,9 +106,17 @@ jobs:
     uses: ./.github/workflows/upload_binaries.yml
     with:
       matrix: ${{ needs.Matrix.outputs.matrix }}
+    permissions:
+      contents: write # For deleting/creating a (pre)release
+    secrets:
+      token: ${{ secrets.GITHUB_TOKEN }}
   ARM_Binaries:
     if: github.repository == 'official-stockfish/Stockfish'
     needs: [Matrix, Prerelease, ARMCompilation]
     uses: ./.github/workflows/upload_binaries.yml
     with:
       matrix: ${{ needs.Matrix.outputs.arm_matrix }}
+    permissions:
+      contents: write # For deleting/creating a (pre)release
+    secrets:
+      token: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/upload_binaries.yml b/.github/workflows/upload_binaries.yml
index c91824a25..c5a2cd105 100644
--- a/.github/workflows/upload_binaries.yml
+++ b/.github/workflows/upload_binaries.yml
@@ -5,6 +5,9 @@ on:
       matrix:
         type: string
         required: true
+    secrets:
+      token:
+        required: true
 
 jobs:
   Artifacts:
@@ -80,6 +83,7 @@ jobs:
         uses: softprops/action-gh-release@4634c16e79c963813287e889244c50009e7f0981
         with:
           files: stockfish-${{ matrix.config.simple_name }}-${{ matrix.binaries }}.${{ matrix.config.archive_ext }}
+          token: ${{ secrets.token }}
 
       - name: Get last commit sha
         id: last_commit
@@ -106,3 +110,4 @@ jobs:
           tag_name: stockfish-dev-${{ env.COMMIT_DATE }}-${{ env.COMMIT_SHA }}
           prerelease: true
           files: stockfish-${{ matrix.config.simple_name }}-${{ matrix.binaries }}.${{ matrix.config.archive_ext }}
+          token: ${{ secrets.token }}