Merge branch 'official-stockfish:master' into master

Current master prohibits usage of LMR for 2nd move at rootNode. This patch also disables LMR for 2nd move not only at rootNode but also at first PvNode that is a reply to rootNode.

passed STC:
https://tests.stockfishchess.org/tests/view/620e8c9026f5b17ec885143a
LLR: 2.94 (-2.94,2.94) <0.00,2.50>
Total: 54096 W: 14305 L: 13996 D: 25795
Ptnml(0-2): 209, 6075, 14192, 6342, 230

passed LTC:
https://tests.stockfishchess.org/tests/view/620eb327b1792e8985f81fb8
LLR: 2.94 (-2.94,2.94) <0.50,3.00>
Total: 110864 W: 29602 L: 29156 D: 52106
Ptnml(0-2): 112, 11147, 32455, 11619, 99

closes https://github.com/official-stockfish/Stockfish/pull/3940

bench 6820724

.github/workflows/stockfish.yml

@@ -0,0 +1,333 @@
+name: Stockfish
+on:
+  push:
+    branches:
+      - master
+      - tools
+      - github_ci
+      - github_ci_armv7
+  pull_request:
+    branches:
+      - master
+      - tools
+jobs:
+  Stockfish:
+    name: ${{ matrix.config.name }}
+    runs-on: ${{ matrix.config.os }}
+    env:
+      COMPILER: ${{ matrix.config.compiler }}
+      COMP: ${{ matrix.config.comp }}
+      CXXFLAGS: "-Werror"
+    strategy:
+      matrix:
+        config:
+          # set the variable for the required tests:
+          # run_expensive_tests: true
+          # run_32bit_tests: true
+          # run_64bit_tests: true
+          # run_armv8_tests: true
+          # run_armv7_tests: true
+          - {
+              name: "Ubuntu 20.04 GCC",
+              os: ubuntu-20.04,
+              compiler: g++,
+              comp: gcc,
+              run_expensive_tests: true,
+              run_32bit_tests: true,
+              run_64bit_tests: true,
+              shell: 'bash {0}'
+            }
+          - {
+              name: "Ubuntu 20.04 Clang",
+              os: ubuntu-20.04,
+              compiler: clang++,
+              comp: clang,
+              run_32bit_tests: true,
+              run_64bit_tests: true,
+              shell: 'bash {0}'
+            }
+          - {
+              name: "Ubuntu 20.04 NDK armv8",
+              os: ubuntu-20.04,
+              compiler: aarch64-linux-android21-clang++,
+              comp: ndk,
+              run_armv8_tests: true,
+              shell: 'bash {0}'
+            }
+          - {
+              name: "Ubuntu 20.04 NDK armv7",
+              os: ubuntu-20.04,
+              compiler: armv7a-linux-androideabi21-clang++,
+              comp: ndk,
+              run_armv7_tests: true,
+              shell: 'bash {0}'
+            }
+          - {
+              name: "MacOS 10.15 Apple Clang",
+              os: macos-10.15,
+              compiler: clang++,
+              comp: clang,
+              run_64bit_tests: true,
+              shell: 'bash {0}'
+            }
+          - {
+              name: "MacOS 10.15 GCC 10",
+              os: macos-10.15,
+              compiler: g++-10,
+              comp: gcc,
+              run_64bit_tests: true,
+              shell: 'bash {0}'
+            }
+          - {
+              name: "Windows 2022 Mingw-w64 GCC x86_64",
+              os: windows-2022,
+              compiler: g++,
+              comp: gcc,
+              run_64bit_tests: true,
+              msys_sys: 'mingw64',
+              msys_env: 'x86_64',
+              shell: 'msys2 {0}'
+            }
+          - {
+              name: "Windows 2022 Mingw-w64 GCC i686",
+              os: windows-2022,
+              compiler: g++,
+              comp: gcc,
+              run_32bit_tests: true,
+              msys_sys: 'mingw32',
+              msys_env: 'i686',
+              shell: 'msys2 {0}'
+            }
+          - {
+              name: "Windows 2022 Mingw-w64 Clang x86_64",
+              os: windows-2022,
+              compiler: clang++,
+              comp: clang,
+              run_64bit_tests: true,
+              msys_sys: 'clang64',
+              msys_env: 'clang-x86_64',
+              shell: 'msys2 {0}'
+            }
+
+    defaults:
+      run:
+        working-directory: src
+        shell: ${{ matrix.config.shell }}
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+
+      - name: Download required linux packages
+        if: runner.os == 'Linux'
+        run: |
+          sudo apt update
+          sudo apt install expect valgrind g++-multilib qemu-user
+
+      - name: Setup msys and install required packages
+        if: runner.os == 'Windows'
+        uses: msys2/setup-msys2@v2
+        with:
+          msystem: ${{matrix.config.msys_sys}}
+          install: mingw-w64-${{matrix.config.msys_env}}-${{matrix.config.comp}} make git expect
+
+      - name: Download the used network from the fishtest framework
+        run: |
+          make net
+
+      - name: Extract the bench number from the commit history
+        run: |
+          git log HEAD | grep "\b[Bb]ench[ :]\+[0-9]\{7\}" | head -n 1 | sed "s/[^0-9]*\([0-9]*\).*/\1/g" > git_sig
+          [ -s git_sig ] && echo "benchref=$(cat git_sig)" >> $GITHUB_ENV && echo "Reference bench:" $(cat git_sig) || echo "No bench found"
+
+      - name: Check compiler
+        run: |
+          export PATH=$PATH:$ANDROID_NDK_HOME/toolchains/llvm/prebuilt/linux-x86_64/bin
+          $COMPILER -v
+
+      - name: Test help target
+        run: |
+          make help
+
+      # x86-32 tests
+
+      - name: Test debug x86-32 build
+        if: ${{ matrix.config.run_32bit_tests }}
+        run: |
+          export CXXFLAGS="-Werror -D_GLIBCXX_DEBUG"
+          make clean
+          make -j2 ARCH=x86-32 optimize=no debug=yes build
+          ../tests/signature.sh $benchref
+
+      - name: Test x86-32 build
+        if: ${{ matrix.config.run_32bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=x86-32 build
+          ../tests/signature.sh $benchref
+
+      - name: Test x86-32-sse41-popcnt build
+        if: ${{ matrix.config.run_32bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=x86-32-sse41-popcnt build
+          ../tests/signature.sh $benchref
+
+      - name: Test x86-32-sse2 build
+        if: ${{ matrix.config.run_32bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=x86-32-sse2 build
+          ../tests/signature.sh $benchref
+
+      - name: Test general-32 build
+        if: ${{ matrix.config.run_32bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=general-32 build
+          ../tests/signature.sh $benchref
+
+      # x86-64 tests
+
+      - name: Test debug x86-64-modern build
+        if: ${{ matrix.config.run_64bit_tests }}
+        run: |
+          export CXXFLAGS="-Werror -D_GLIBCXX_DEBUG"
+          make clean
+          make -j2 ARCH=x86-64-modern optimize=no debug=yes build
+          ../tests/signature.sh $benchref
+
+      - name: Test x86-64-modern build
+        if: ${{ matrix.config.run_64bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=x86-64-modern build
+          ../tests/signature.sh $benchref
+
+      - name: Test x86-64-ssse3 build
+        if: ${{ matrix.config.run_64bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=x86-64-ssse3 build
+          ../tests/signature.sh $benchref
+
+      - name: Test x86-64-sse3-popcnt build
+        if: ${{ matrix.config.run_64bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=x86-64-sse3-popcnt build
+          ../tests/signature.sh $benchref
+
+      - name: Test x86-64 build
+        if: ${{ matrix.config.run_64bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=x86-64 build
+          ../tests/signature.sh $benchref
+
+      - name: Test general-64 build
+        if: matrix.config.run_64bit_tests
+        run: |
+          make clean
+          make -j2 ARCH=general-64 build
+          ../tests/signature.sh $benchref
+
+      # x86-64 with newer extensions tests
+
+      - name: Compile x86-64-avx2 build
+        if: ${{ matrix.config.run_64bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=x86-64-avx2 build
+
+      - name: Compile x86-64-bmi2 build
+        if: ${{ matrix.config.run_64bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=x86-64-bmi2 build
+
+      - name: Compile x86-64-avx512 build
+        if: ${{ matrix.config.run_64bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=x86-64-avx512 build
+
+      - name: Compile x86-64-vnni512 build
+        if: ${{ matrix.config.run_64bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=x86-64-vnni512 build
+
+      - name: Compile x86-64-vnni256 build
+        if: ${{ matrix.config.run_64bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=x86-64-vnni256 build
+
+      # armv8 tests
+
+      - name: Test armv8 build
+        if: ${{ matrix.config.run_armv8_tests }}
+        run: |
+          export PATH=$ANDROID_NDK_HOME/toolchains/llvm/prebuilt/linux-x86_64/bin:$PATH
+          export LDFLAGS="-static -Wno-unused-command-line-argument"
+          make clean
+          make -j2 ARCH=armv8 build
+          ../tests/signature.sh $benchref
+
+      # armv7 tests
+
+      - name: Test armv7 build
+        if: ${{ matrix.config.run_armv7_tests }}
+        run: |
+          export PATH=$ANDROID_NDK_HOME/toolchains/llvm/prebuilt/linux-x86_64/bin:$PATH
+          export LDFLAGS="-static -Wno-unused-command-line-argument"
+          make clean
+          make -j2 ARCH=armv7 build
+          ../tests/signature.sh $benchref
+
+      - name: Test armv7-neon build
+        if: ${{ matrix.config.run_armv7_tests }}
+        run: |
+          export PATH=$ANDROID_NDK_HOME/toolchains/llvm/prebuilt/linux-x86_64/bin:$PATH
+          export LDFLAGS="-static -Wno-unused-command-line-argument"
+          make clean
+          make -j2 ARCH=armv7-neon build
+          ../tests/signature.sh $benchref
+
+      # Other tests
+
+      - name: Check perft and search reproducibility
+        if: ${{ matrix.config.run_64bit_tests }}
+        run: |
+          make clean
+          make -j2 ARCH=x86-64-modern build
+          ../tests/perft.sh
+          ../tests/reprosearch.sh
+
+      # Sanitizers
+
+      - name: Run under valgrind
+        if: ${{ matrix.config.run_expensive_tests }}
+        run: |
+          export CXXFLAGS="-O1 -fno-inline"
+          make clean
+          make -j2 ARCH=x86-64-modern debug=yes optimize=no build > /dev/null
+          ../tests/instrumented.sh --valgrind
+          ../tests/instrumented.sh --valgrind-thread
+
+      - name: Run with UB sanitizer
+        if: ${{ matrix.config.run_expensive_tests }}
+        run: |
+          export CXXFLAGS="-O1 -fno-inline"
+          make clean
+          make -j2 ARCH=x86-64-modern sanitize=undefined optimize=no debug=yes build > /dev/null
+          ../tests/instrumented.sh --sanitizer-undefined
+
+      - name: Run with thread sanitizer
+        if: ${{ matrix.config.run_expensive_tests }}
+        run: |
+          export CXXFLAGS="-O1 -fno-inline"
+          make clean
+          make -j2 ARCH=x86-64-modern sanitize=thread optimize=no debug=yes build > /dev/null
+          ../tests/instrumented.sh --sanitizer-thread

.travis.yml

@@ -1,101 +0,0 @@
-language: cpp
-dist: bionic
-
-matrix:
-  include:
-    - os: linux
-      compiler: gcc
-      addons:
-        apt:
-          packages: ['g++-8', 'g++-8-multilib', 'g++-multilib', 'valgrind', 'expect', 'curl']
-      env:
-        - COMPILER=g++-8
-        - COMP=gcc
-
-    - os: linux
-      compiler: clang
-      addons:
-        apt:
-          packages: ['clang-10', 'llvm-10-dev', 'g++-multilib', 'valgrind', 'expect', 'curl']
-      env:
-        - COMPILER=clang++-10
-        - COMP=clang
-
-    - os: osx
-      osx_image: xcode12
-      compiler: gcc
-      env:
-        - COMPILER=g++
-        - COMP=gcc
-
-    - os: osx
-      osx_image: xcode12
-      compiler: clang
-      env:
-        - COMPILER=clang++
-        - COMP=clang
-
-branches:
-  only:
-   - master
-
-before_script:
-  - cd src
-
-script:
-  # Download net
-  - make net
-
-  # Obtain bench reference from git log
-  - git log HEAD | grep "\b[Bb]ench[ :]\+[0-9]\{7\}" | head -n 1 | sed "s/[^0-9]*\([0-9]*\).*/\1/g" > git_sig
-  - export benchref=$(cat git_sig)
-  - echo "Reference bench:" $benchref
-
-  # Compiler version string
-  - $COMPILER -v
-
-  # test help target
-  - make help
-
-  # Verify bench number against various builds
-  - export CXXFLAGS="-Werror -D_GLIBCXX_DEBUG"
-  - make clean && make -j2 ARCH=x86-64-modern optimize=no debug=yes build && ../tests/signature.sh $benchref
-  - export CXXFLAGS="-Werror"
-  - make clean && make -j2 ARCH=x86-64-modern build && ../tests/signature.sh $benchref
-  - make clean && make -j2 ARCH=x86-64-ssse3 build && ../tests/signature.sh $benchref
-  - make clean && make -j2 ARCH=x86-64-sse3-popcnt build && ../tests/signature.sh $benchref
-  - make clean && make -j2 ARCH=x86-64 build && ../tests/signature.sh $benchref
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then make clean && make -j2 ARCH=general-64 build && ../tests/signature.sh $benchref; fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then make clean && make -j2 ARCH=x86-32 optimize=no debug=yes build && ../tests/signature.sh $benchref; fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then make clean && make -j2 ARCH=x86-32-sse41-popcnt build && ../tests/signature.sh $benchref; fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then make clean && make -j2 ARCH=x86-32-sse2 build && ../tests/signature.sh $benchref; fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then make clean && make -j2 ARCH=x86-32 build && ../tests/signature.sh $benchref; fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then make clean && make -j2 ARCH=general-32 build && ../tests/signature.sh $benchref; fi
-  # workaround: exclude a custom version of llvm+clang, which doesn't find llvm-profdata on ubuntu
-  - if [[ "$TRAVIS_OS_NAME" != "linux" || "$COMP" == "gcc" ]]; then make clean && make -j2 ARCH=x86-64-modern profile-build && ../tests/signature.sh $benchref; fi
-
-  # compile only for some more advanced architectures (might not run in travis)
-  - make clean && make -j2 ARCH=x86-64-avx2 build
-  - make clean && make -j2 ARCH=x86-64-bmi2 build
-  - make clean && make -j2 ARCH=x86-64-avx512 build
-  - make clean && make -j2 ARCH=x86-64-vnni512 build
-  - make clean && make -j2 ARCH=x86-64-vnni256 build
-
-  #
-  # Check perft and reproducible search
-  - make clean && make -j2 ARCH=x86-64-modern build
-  - ../tests/perft.sh
-  - ../tests/reprosearch.sh
-
-  #
-  # Valgrind
-  #
-  - export CXXFLAGS="-O1 -fno-inline"
-  - if [ -x "$(command -v valgrind )" ]; then make clean && make -j2 ARCH=x86-64-modern debug=yes optimize=no build > /dev/null && ../tests/instrumented.sh --valgrind; fi
-  - if [ -x "$(command -v valgrind )" ]; then ../tests/instrumented.sh --valgrind-thread; fi
-
-  #
-  # Sanitizer
-  #
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then make clean && make -j2 ARCH=x86-64-modern sanitize=undefined optimize=no debug=yes build > /dev/null && ../tests/instrumented.sh --sanitizer-undefined; fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then make clean && make -j2 ARCH=x86-64-modern sanitize=thread    optimize=no debug=yes build > /dev/null && ../tests/instrumented.sh --sanitizer-thread; fi

AUTHORS

@@ -1,4 +1,4 @@
-# List of authors for Stockfish, as of August 4, 2020
+# List of authors for Stockfish
 
 # Founders of the Stockfish project and fishtest infrastructure
 Tord Romstad (romstad)
@@ -21,11 +21,14 @@ Alexander Kure
 Alexander Pagel (Lolligerhans)
 Alfredo Menezes (lonfom169)
 Ali AlZhrani (Cooffe)
+Andrei Vetrov (proukornew)
 Andrew Grant (AndyGrant)
 Andrey Neporada (nepal)
 Andy Duplain
+Antoine Champion (antoinechampion)
 Aram Tumanian (atumanian)
 Arjun Temurnikar
+Artem Solopiy (EntityFX)
 Auguste Pop
 Balint Pfliegel
 Ben Koshy (BKSpurgeon)
@@ -50,6 +53,7 @@ Dieter Dobbelaere (ddobbelaere)
 DiscanX
 Dominik Schlösser (domschl)
 double-beep
+Douglas Matos Gomes (dsmsgms)
 Eduardo Cáceres (eduherminio)
 Eelco de Groot (KingDefender)
 Elvin Liu (solarlight2)
@@ -66,6 +70,7 @@ gamander
 Gary Heckman (gheckman)
 George Sobala (gsobala)
 gguliash
+Giacomo Lorenzetti (G-Lorenz)
 Gian-Carlo Pascutto (gcp)
 Gontran Lemaire (gonlem)
 Goodkov Vasiliy Aleksandrovich (goodkov)
@@ -93,6 +98,7 @@ Joost VandeVondele (vondele)
 Jörg Oster (joergoster)
 Joseph Ellis (jhellis3)
 Joseph R. Prostko
+Julian Willemer (NightlyKing)
 jundery
 Justin Blanchard (UncombedCoconut)
 Kelly Wilson
@@ -103,6 +109,7 @@ Kojirion
 Krystian Kuzniarek (kuzkry)
 Leonardo Ljubičić (ICCF World Champion)
 Leonid Pechenik (lp--)
+Liam Keegan (lkeegan)
 Linus Arver (listx)
 loco-loco
 Lub van den Berg (ElbertoOne)
@@ -125,6 +132,7 @@ Michael Whiteley (protonspring)
 Michel Van den Bergh (vdbergh)
 Miguel Lahoz (miguel-l)
 Mikael Bäckman (mbootsector)
+Mike Babigian (Farseer)
 Mira
 Miroslav Fontán (Hexik)
 Moez Jellouli (MJZ1977)
@@ -137,6 +145,7 @@ Nikolay Kostov (NikolayIT)
 Nguyen Pham (nguyenpham)
 Norman Schmidt (FireFather)
 notruck
+Ofek Shochat (OfekShochat, ghostway)
 Ondrej Mosnáček (WOnder93)
 Oskar Werkelin Ahlin
 Pablo Vazquez
@@ -157,6 +166,7 @@ Rodrigo Exterckötter Tjäder
 Ron Britvich (Britvich)
 Ronald de Man (syzygy1, syzygy)
 rqs
+Rui Coelho (ruicoelhopedro)
 Ryan Schmitt
 Ryan Takker
 Sami Kiminki (skiminki)
@@ -167,10 +177,12 @@ Sergio Vieri (sergiovieri)
 sf-x
 Shane Booth (shane31)
 Shawn Varghese (xXH4CKST3RXx)
+Siad Daboul (Topologist)
 Stefan Geschwentner (locutus2)
 Stefano Cardanobile (Stefano80)
 Steinar Gunderson (sesse)
 Stéphane Nicolet (snicolet)
+Prokop Randáček (ProkopRandacek)
 Thanar2
 thaspel
 theo77186
@@ -178,11 +190,13 @@ Tom Truscott
 Tom Vijlbrief (tomtor)
 Tomasz Sobczyk (Sopel97)
 Torsten Franz (torfranz, tfranzer)
+Torsten Hellwig (Torom)
 Tracey Emery (basepr1me)
 tttak
 Unai Corzo (unaiic)
 Uri Blass (uriblass)
 Vince Negri (cuddlestmonkey)
+xefoci7612
 zz4032
 
 

README.md

@@ -2,7 +2,7 @@ Modified stockfish to play the worst move. Play against the bot at https://liche
 
 ## Overview
 
-[![Build Status](https://travis-ci.org/official-stockfish/Stockfish.svg?branch=master)](https://travis-ci.org/official-stockfish/Stockfish)
+[![Build Status](https://github.com/official-stockfish/Stockfish/actions/workflows/stockfish.yml/badge.svg)](https://github.com/official-stockfish/Stockfish/actions)
 [![Build Status](https://ci.appveyor.com/api/projects/status/github/official-stockfish/Stockfish?branch=master&svg=true)](https://ci.appveyor.com/project/mcostalba/stockfish/branch/master)
 
 [Stockfish](https://stockfishchess.org) is a free, powerful UCI chess engine
@@ -23,21 +23,28 @@ intrinsics available on most CPUs (sse2, avx2, neon, or similar).
 
 This distribution of Stockfish consists of the following files:
 
-  * Readme.md, the file you are currently reading.
+  * [Readme.md](https://github.com/official-stockfish/Stockfish/blob/master/README.md), the file you are currently reading.
 
-  * Copying.txt, a text file containing the GNU General Public License version 3.
+  * [Copying.txt](https://github.com/official-stockfish/Stockfish/blob/master/Copying.txt), a text file containing the GNU General Public License version 3.
-  
-  * AUTHORS, a text file with the list of authors for the project
 
-  * src, a subdirectory containing the full source code, including a Makefile
+  * [AUTHORS](https://github.com/official-stockfish/Stockfish/blob/master/AUTHORS), a text file with the list of authors for the project
+
+  * [src](https://github.com/official-stockfish/Stockfish/tree/master/src), a subdirectory containing the full source code, including a Makefile
     that can be used to compile Stockfish on Unix-like systems.
 
-  * a file with the .nnue extension, storing the neural network for the NNUE 
+  * a file with the .nnue extension, storing the neural network for the NNUE
     evaluation. Binary distributions will have this file embedded.
 
-## UCI options
+## The UCI protocol and available options
 
-Currently, Stockfish has the following UCI options:
+The Universal Chess Interface (UCI) is a standard protocol used to communicate with
+a chess engine, and is the recommended way to do so for typical graphical user interfaces
+(GUI) or chess tools. Stockfish implements the majority of it options as described
+in [the UCI protocol](https://www.shredderchess.com/download/div/uci.zip).
+
+Developers can see the default values for UCI options available in Stockfish by typing
+`./stockfish uci` in a terminal, but the majority of users will typically see them and
+change them via a chess GUI. This is a list of available UCI options in Stockfish:
 
   * #### Threads
     The number of CPU threads used for searching a position. For best performance, set
@@ -115,14 +122,6 @@ Currently, Stockfish has the following UCI options:
     Limit Syzygy tablebase probing to positions with at most this many pieces left
     (including kings and pawns).
 
-  * #### Contempt
-    A positive value for contempt favors middle game positions and avoids draws,
-    effective for the classical evaluation only.
-
-  * #### Analysis Contempt
-    By default, contempt is set to prefer the side to move. Set this option to "White"
-    or "Black" to analyse with contempt for that side, or "Off" to disable contempt.
-
   * #### Move Overhead
     Assume a time delay of x ms due to network and GUI overheads. This is useful to
     avoid losses on time in those cases.
@@ -138,6 +137,34 @@ Currently, Stockfish has the following UCI options:
   * #### Debug Log File
     Write all communication to and from the engine into a text file.
 
+For developers the following non-standard commands might be of interest, mainly useful for debugging:
+
+  * #### bench *ttSize threads limit fenFile limitType evalType*
+    Performs a standard benchmark using various options. The signature of a version (standard node
+    count) is obtained using all defaults. `bench` is currently `bench 16 1 13 default depth mixed`.
+
+  * #### compiler
+    Give information about the compiler and environment used for building a binary.
+
+  * #### d
+    Display the current position, with ascii art and fen.
+
+  * #### eval
+    Return the evaluation of the current position.
+
+  * #### export_net [filename]
+    Exports the currently loaded network to a file.
+    If the currently loaded network is the embedded network and the filename
+    is not specified then the network is saved to the file matching the name
+    of the embedded network, as defined in evaluate.h.
+    If the currently loaded network is not the embedded network (some net set
+    through the UCI setoption) then the filename parameter is required and the
+    network is saved into that file.
+
+  * #### flip
+    Flips the side to move.
+
+
 ## A note on classical evaluation versus NNUE evaluation
 
 Both approaches assign a value to a position that is used in alpha-beta (PVS) search
@@ -150,8 +177,12 @@ on the evaluations of millions of positions at moderate search depth.
 The NNUE evaluation was first introduced in shogi, and ported to Stockfish afterward.
 It can be evaluated efficiently on CPUs, and exploits the fact that only parts
 of the neural network need to be updated after a typical chess move.
-[The nodchip repository](https://github.com/nodchip/Stockfish) provides additional
+[The nodchip repository](https://github.com/nodchip/Stockfish) provided the first version of
-tools to train and develop the NNUE networks. On CPUs supporting modern vector instructions
+the needed tools to train and develop the NNUE networks. Today, more advanced training tools are available
+in [the nnue-pytorch repository](https://github.com/glinscott/nnue-pytorch/), while data generation tools
+are available in [a dedicated branch](https://github.com/official-stockfish/Stockfish/tree/tools).
+
+On CPUs supporting modern vector instructions
 (avx2 and similar), the NNUE evaluation results in much stronger playing strength, even
 if the nodes per second computed by the engine is somewhat lower (roughly 80% of nps
 is typical).
@@ -164,7 +195,7 @@ Stockfish binary, but the default value of the EvalFile UCI option is the name o
 that is guaranteed to be compatible with that binary.
 
 2) to use the NNUE evaluation, the additional data file with neural network parameters
-needs to be available. Normally, this file is already embedded in the binary or it 
+needs to be available. Normally, this file is already embedded in the binary or it
 can be downloaded. The filename for the default (recommended) net can be found as the default
 value of the `EvalFile` UCI option, with the format `nn-[SHA256 first 12 digits].nnue`
 (for instance, `nn-c157e0a5755b.nnue`). This file can be downloaded from
@@ -177,7 +208,7 @@ replacing `[filename]` as needed.
 
 If the engine is searching a position that is not in the tablebases (e.g.
 a position with 8 pieces), it will access the tablebases during the search.
-If the engine reports a very large score (typically 153.xx), this means 
+If the engine reports a very large score (typically 153.xx), this means
 it has found a winning line into a tablebase position.
 
 If the engine is given a position to search that is in the tablebases, it
@@ -244,9 +275,9 @@ When not using the Makefile to compile (for instance, with Microsoft MSVC) you
 need to manually set/unset some switches in the compiler command line; see
 file *types.h* for a quick reference.
 
-When reporting an issue or a bug, please tell us which version and
+When reporting an issue or a bug, please tell us which Stockfish version
-compiler you used to create your executable. These informations can
+and which compiler you used to create your executable. This information
-be found by typing the following commands in a console:
+can be found by typing the following command in a console:
 
 ```
     ./stockfish compiler
@@ -254,8 +285,8 @@ be found by typing the following commands in a console:
 
 ## Understanding the code base and participating in the project
 
-Stockfish's improvement over the last couple of years has been a great
+Stockfish's improvement over the last decade has been a great community
-community effort. There are a few ways to help contribute to its growth.
+effort. There are a few ways to help contribute to its growth.
 
 ### Donating hardware
 
@@ -299,4 +330,4 @@ you are distributing. If you make any changes to the source code,
 these changes must also be made available under the GPL.
 
 For full details, read the copy of the GPL v3 found in the file named
-*Copying.txt*.
+[*Copying.txt*](https://github.com/official-stockfish/Stockfish/blob/master/Copying.txt).

Top CPU Contributors.txt

@@ -1,189 +1,230 @@
-Contributors to Fishtest with >10,000 CPU hours, as of Feb 15, 2021.
+Contributors to Fishtest with >10,000 CPU hours, as of 2022-02-05.
 Thank you!
 
-Username                CPU Hours       Games played
+Username                                CPU Hours     Games played
-----------------------------------------------------
+------------------------------------------------------------------
-noobpwnftw               23930906         1560559941
+noobpwnftw                               30730952       2158431735
-dew                       1169948           70333008
+mlang                                     2729669        187335452
-mlang                      957168           61657446
+technologov                               1696847         74478658
-mibere                     703840           46867607
+dew                                       1635640         97483012
-tvijlbrief                 517888           33379462
+grandphish2                               1062754         64955639
-JojoM                      515404           30334272
+tvijlbrief                                 795993         51894442
-cw                         443276           29385549
+okrout                                     773704         63465204
-crunchy                    427035           27344275
+TueRens                                    766198         47770388
-grandphish2                425794           26347253
+mibere                                     703840         46867607
-fastgm                     414133           24519696
+JojoM                                      703005         42689868
-gvreuls                    377843           24708884
+pemo                                       634102         29868807
-CSU_Dynasty                338718           23030006
+linrock                                    626939         17408017
-Fisherman                  326795           21820747
+gvreuls                                    517442         33605006
-TueRens                    313730           19490246
+cw                                         503905         33850487
-ctoks                      298442           20052551
+fastgm                                     482847         29004732
-velislav                   270519           17355456
+crunchy                                    427035         27344275
-bcross                     241064           17196165
+CSU_Dynasty                                415864         28116776
-glinscott                  217799           13780820
+ctoks                                      403102         26737127
-nordlandia                 211692           13484886
+oz                                         357710         26490208
-bking_US                   198894           11876016
+bcross                                     331095         23165889
-drabel                     191096           13129722
+Fisherman                                  327231         21829379
-leszek                     189170           11446821
+velislav                                   321708         20729264
-mgrabiak                   187153           12013300
+leszek                                     303654         19063973
-robal                      181389           11539242
+Dantist                                    251015         15843226
-Thanar                     179852           12365359
+mgrabiak                                   231973         15162494
-vdv                        175274            9889046
+glinscott                                  217799         13780820
-spams                      157128           10319326
+robal                                      213960         13665726
-marrco                     150292            9401741
+nordlandia                                 211692         13484886
-sqrt2                      147963            9724586
+drabel                                     200914         13755384
-CoffeeOne                  137086            5022516
+bking_US                                   198894         11876016
-vdbergh                    137041            8926915
+mhoram                                     180229         11610075
-malala                     136182            8002293
+Thanar                                     179852         12365359
-mhoram                     132780            8398229
+vdv                                        175544          9904472
-xoto                       124729            8652088
+spams                                      157128         10319326
-davar                      122092            7960001
+marrco                                     150300          9402229
-dsmith                     122059            7570238
+sqrt2                                      147963          9724586
-Data                       113305            8220352
+vdbergh                                    137429          8955089
-BrunoBanani                112960            7436849
+CoffeeOne                                  137100          5024116
-pemo                       109598            5036441
+malala                                     136182          8002293
-Dantist                    106768            6431396
+xoto                                       133759          9159372
-MaZePallas                 102741            6630419
+rpngn                                      131285          8657757
-ElbertoOne                  99028            7023771
+davar                                      122661          7996937
-brabos                      92118            6186135
+dsmith                                     122059          7570238
-linrock                     90903            6708639
+amicic                                     119659          7937885
-psk                         89957            5984901
+Data                                       113305          8220352
-sunu                        88614            6020673
+BrunoBanani                                112960          7436849
-sterni1971                  86948            5613788
+CypressChess                               108321          7759588
-Vizvezdenec                 83761            5344740
+MaZePallas                                 102823          6633619
-BRAVONE                     81239            5054681
+sterni1971                                 100532          5880772
-nssy                        76497            5259388
+sunu                                       100167          7040199
-cuistot                     76366            4370584
+DesolatedDodo                               99038          6414626
-racerschmacer               75753            5442626
+ElbertoOne                                  99028          7023771
-teddybaer                   75125            5407666
+skiminki                                    98123          6478402
-Pking_cda                   73776            5293873
+brabos                                      92118          6186135
-0x3C33                      73133            4670293
+cuistot                                     90358          5351004
-jromang                     72117            5054915
+psk                                         89957          5984901
-solarlight                  70517            5028306
+racerschmacer                               85712          6119648
-dv8silencer                 70287            3883992
+Vizvezdenec                                 83761          5344740
-Bobo1239                    68515            4652287
+sschnee                                     83003          4840890
-manap                       66273            4121774
+0x3C33                                      82614          5271253
-tinker                      64321            4268390
+BRAVONE                                     81239          5054681
-robnjr                      57262            4053117
+nssy                                        76497          5259388
-Freja                       56938            3733019
+teddybaer                                   75125          5407666
-ttruscott                   56010            3680085
+Pking_cda                                   73776          5293873
-rkl                         54986            4150767
+zeryl                                       73335          4774257
-renouve                     53811            3501516
+jromang                                     72192          5057715
-finfish                     51360            3370515
+solarlight                                  70517          5028306
-eva42                       51272            3599691
+dv8silencer                                 70287          3883992
-rap                         49985            3219146
+Bobo1239                                    68515          4652287
-pb00067                     49727            3298270
+manap                                       66273          4121774
-amicic                      49691            3042481
+tinker                                      64333          4268790
-ronaldjerum                 47654            3240695
+yurikvelo                                   63371          4335060
-bigpen0r                    47278            3291647
+qurashee                                    61208          3429862
-biffhero                    46564            3111352
+robnjr                                      57262          4053117
-VoyagerOne                  45476            3452465
+Wolfgang                                    57014          3561352
-eastorwest                  45033            3071805
+Freja                                       56938          3733019
-speedycpu                   43842            3003273
+ttruscott                                   56010          3680085
-jbwiebe                     43305            2805433
+rkl                                         55132          4164467
-Antihistamine               41788            2761312
+renouve                                     53811          3501516
-mhunt                       41735            2691355
+finfish                                     51360          3370515
-homyur                      39893            2850481
+eva42                                       51272          3599691
-gri                         39871            2515779
+Calis007                                    51182          3131552
-oryx                        38282            2944400
+eastorwest                                  51058          3451555
-Spprtr                      38157            2470529
+rap                                         49985          3219146
-SC                          37290            2731014
+pb00067                                     49727          3298270
-csnodgrass                  36207            2688994
+Spprtr                                      48260          3141959
-jmdana                      36157            2210661
+bigpen0r                                    47667          3336927
-strelock                    34716            2074055
+ronaldjerum                                 47654          3240695
-Garf                        33800            2747562
+MaxKlaxxMiner                               47584          2972142
-skiminki                    33515            2055584
+biffhero                                    46564          3111352
-EthanOConnor                33370            2090311
+megaman7de                                  45992          2952006
-slakovv                     32915            2021889
+Fifis                                       45843          3088497
-yurikvelo                   32600            2255966
+VoyagerOne                                  45476          3452465
-Prcuvu                      30377            2170122
+speedycpu                                   43842          3003273
-manapbk                     30326            1770143
+jbwiebe                                     43305          2805433
-anst                        30301            2190091
+Antihistamine                               41788          2761312
-jkiiski                     30136            1904470
+mhunt                                       41735          2691355
-hyperbolic.tom              29840            2017394
+homyur                                      39893          2850481
-Pyafue                      29650            1902349
+gri                                         39871          2515779
-qurashee                    27758            1509620
+oryx                                        38867          2976992
-OuaisBla                    27636            1578800
+SC                                          37299          2731694
-chriswk                     26902            1868317
+Garf                                        37213          2986270
-achambord                   26582            1767323
+csnodgrass                                  36207          2688994
-Fifis                       26376            1776853
+jmdana                                      36157          2210661
-Patrick_G                   26276            1801617
+strelock                                    34716          2074055
-yorkman                     26193            1992080
+EthanOConnor                                33370          2090311
-SFTUser                     25182            1675689
+slakovv                                     32915          2021889
-nabildanial                 24942            1519409
+armo9494                                    32129          2551682
-Sharaf_DG                   24765            1786697
+tolkki963                                   32114          1932256
-ncfish1                     24411            1520927
+manapbk                                     30987          1810399
-agg177                      23890            1395014
+DMBK                                        30675          2383552
-JanErik                     23408            1703875
+Prcuvu                                      30377          2170122
-Isidor                      23388            1680691
+anst                                        30301          2190091
-Norabor                     23164            1591830
+jkiiski                                     30136          1904470
-cisco2015                   22895            1762069
+gopeto                                      29886          1979118
-Zirie                       22542            1472937
+hyperbolic.tom                              29840          2017394
-team-oh                     22272            1636708
+chuckstablers                               29659          2093438
-MazeOfGalious               21978            1629593
+Pyafue                                      29650          1902349
-sg4032                      21945            1643065
+OuaisBla                                    27636          1578800
-ianh2105                    21725            1632562
+chriswk                                     26902          1868317
-xor12                       21628            1680365
+achambord                                   26582          1767323
-dex                         21612            1467203
+Patrick_G                                   26276          1801617
-nesoneg                     21494            1463031
+yorkman                                     26193          1992080
-jjoshua2                    20997            1422689
+SFTUser                                     25182          1675689
-horst.prack                 20878            1465656
+nabildanial                                 24942          1519409
-0xB00B1ES                   20590            1208666
+Sharaf_DG                                   24765          1786697
-sphinx                      20515            1352368
+ncfish1                                     24411          1520927
-j3corre                     20405            941444
+rodneyc                                     24275          1410450
-Adrian.Schmidt123           20316            1281436
+agg177                                      23890          1395014
-Ente                        20017            1432602
+belzedar94                                  23707          1593860
-wei                         19973            1745989
+JanErik                                     23408          1703875
-rstoesser                   19569            1293588
+Isidor                                      23388          1680691
-eudhan                      19274            1283717
+Norabor                                     23339          1602636
-jundery                     18445            1115855
+Ente                                        23093          1642458
-iisiraider                  18247            1101015
+cisco2015                                   22897          1762669
-ville                       17883            1384026
+Zirie                                       22542          1472937
-chris                       17698            1487385
+team-oh                                     22272          1636708
-purplefishies               17595            1092533
+MazeOfGalious                               21978          1629593
-DMBK                        17357            1279152
+sg4032                                      21947          1643265
-DragonLord                  17014            1162790
+ianh2105                                    21725          1632562
-dju                         16515             929427
+xor12                                       21628          1680365
-IgorLeMasson                16064            1147232
+dex                                         21612          1467203
-ako027ako                   15671            1173203
+nesoneg                                     21494          1463031
-Nikolay.IT                  15154            1068349
+sphinx                                      21211          1384728
-Andrew Grant                15114             895539
+jjoshua2                                    21001          1423089
-OssumOpossum                14857            1007129
+horst.prack                                 20878          1465656
-enedene                     14476             905279
+user213718                                  20783          1379584
-bpfliegel                   14298             884523
+0xB00B1ES                                   20590          1208666
-jpulman                     13982             870599
+j3corre                                     20405           941444
-joster                      13794             950160
+Adrian.Schmidt123                           20316          1281436
-Nesa92                      13786            1114691
+wei                                         19973          1745989
-crocogoat                   13753            1114622
+Roady                                       19848          1335928
-Hjax                        13535             915487
+rstoesser                                   19569          1293588
-Dark_wizzie                 13422            1007152
+eudhan                                      19274          1283717
-mpx86                       12941             693640
+vulcan                                      18871          1729392
-mabichito                   12903             749391
+jundery                                     18445          1115855
-thijsk                      12886             722107
+iisiraider                                  18247          1101015
-AdrianSA                    12860             804972
+ville                                       17883          1384026
-Flopzee                     12698             894821
+chris                                       17698          1487385
-fatmurphy                   12547             853210
+purplefishies                               17595          1092533
-scuzzi                      12511             845761
+dju                                         17353           978595
-Karby                       12429             735880
+kdave                                       17183          1242754
-SapphireBrand               12416             969604
+DragonLord                                  17014          1162790
-modolief                    12386             896470
+thirdlife                                   16996           447356
-pgontarz                    12151             848794
+spcc                                        16932          1130940
-stocky                      11954             699440
+fishtester                                  16644          1123000
-mschmidt                    11941             803401
+Ulysses                                     16490          1184400
-infinity                    11470             727027
+IgorLeMasson                                16064          1147232
-torbjo                      11395             729145
+ako027ako                                   15671          1173203
-Thomas A. Anderson          11372             732094
+Nikolay.IT                                  15154          1068349
-d64                         11263             789184
+Andrew Grant                                15114           895539
-Maxim                       11129             804704
+OssumOpossum                                14857          1007129
-snicolet                    11106             869170
+Karby                                       14808           867120
-MooTheCow                   11008             694942
+AndreasKrug                                 14608          1152093
-savage84                    10965             641068
+enedene                                     14476           905279
-Rudolphous                  10915             741268
+jsys14                                      14340           844792
-Wolfgang                    10809             580032
+bpfliegel                                   14298           884523
-rpngn                       10712             688203
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-basepi                      10637             744851
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-michaelrpg                  10409             735127
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-dzjp                        10343             732529
+joster                                      13794           950160
-ali-al-zhrani               10324             726502
+Nesa92                                      13786          1114691
-ols                         10259             570669
+mbeier                                      13650          1044928
-lbraesch                    10252             647825
+Hjax                                        13535           915487
+Dark_wizzie                                 13422          1007152
+Rudolphous                                  13244           883140
+MarcusTullius                               13221           843169
+Machariel                                   13010           863104
+mabichito                                   12903           749391
+thijsk                                      12886           722107
+AdrianSA                                    12860           804972
+infinigon                                   12807           937332
+Flopzee                                     12698           894821
+fatmurphy                                   12547           853210
+scuzzi                                      12511           845761
+SapphireBrand                               12416           969604
+modolief                                    12386           896470
+Farseer                                     12249           694108
+pgontarz                                    12151           848794
+stocky                                      11954           699440
+mschmidt                                    11941           803401
+dbernier                                    11609           818636
+Maxim                                       11543           836024
+pirt                                        11516           894513
+infinity                                    11470           727027
+aga                                         11409           695071
+torbjo                                      11395           729145
+Thomas A. Anderson                          11372           732094
+savage84                                    11358           670860
+markkulix                                   11331           739098
+FormazChar                                  11308           847735
+d64                                         11263           789184
+MooTheCow                                   11237           720174
+snicolet                                    11106           869170
+ali-al-zhrani                               11098           768494
+whelanh                                     11067           235676
+basepi                                      10637           744851
+Cubox                                       10621           826448
+michaelrpg                                  10509           739239
+OIVAS7572                                   10420           995586
+dzjp                                        10343           732529
+Garruk                                      10332           703905
+ols                                         10259           570669
+lbraesch                                    10252           647825
+Jackfish                                    10098           682338

appveyor.yml

@@ -1,88 +0,0 @@
-version: 1.0.{build}
-clone_depth: 50
-
-branches:
-  only:
-    - master
-
-# Operating system (build VM template)
-os: Visual Studio 2019
-
-# Build platform, i.e. x86, x64, AnyCPU. This setting is optional.
-platform:
-  - x86
-  - x64
-
-# build Configuration, i.e. Debug, Release, etc.
-configuration:
-  - Debug
-  - Release
-
-matrix:
-  # The build fail immediately once one of the job fails
-  fast_finish: true
-
-# Scripts that are called at very beginning, before repo cloning
-init:
-  - cmake --version
-  - msbuild /version
-
-before_build:
-  - ps: |
-      # Get sources
-      $src = get-childitem -Path *.cpp -Recurse | select -ExpandProperty FullName
-      $src = $src -join ' '
-      $src = $src.Replace("\", "/")
-
-      # Build CMakeLists.txt
-      $t = 'cmake_minimum_required(VERSION 3.17)',
-           'project(Stockfish)',
-           'set(CMAKE_CXX_STANDARD 17)',
-           'set(CMAKE_CXX_STANDARD_REQUIRED ON)',
-           'set (CMAKE_CXX_EXTENSIONS OFF)',
-           'set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_SOURCE_DIR}/src)',
-           'set(source_files', $src, ')',
-           'add_executable(stockfish ${source_files})'
-
-      # Write CMakeLists.txt withouth BOM
-      $MyPath = (Get-Item -Path "." -Verbose).FullName + '\CMakeLists.txt'
-      $Utf8NoBomEncoding = New-Object System.Text.UTF8Encoding $False
-      [System.IO.File]::WriteAllLines($MyPath, $t, $Utf8NoBomEncoding)
-
-      # Obtain bench reference from git log
-      $b = git log HEAD | sls "\b[Bb]ench[ :]+[0-9]{7}" | select -first 1
-      $bench = $b -match '\D+(\d+)' | % { $matches[1] }
-      Write-Host "Reference bench:" $bench
-      $g = "Visual Studio 16 2019"
-      If (${env:PLATFORM} -eq 'x64') { $a = "x64" }
-      If (${env:PLATFORM} -eq 'x86') { $a = "Win32" }
-      cmake -G "${g}" -A ${a} .
-      Write-Host "Generated files for: " $g $a
-
-build_script:
-  - cmake --build . --config %CONFIGURATION% -- /verbosity:minimal
-  - ps: |
-      # Download default NNUE net from fishtest
-      $nnuenet = Get-Content -Path src\evaluate.h | Select-String -CaseSensitive -Pattern "EvalFileDefaultName" | Select-String -CaseSensitive -Pattern "nn-[a-z0-9]{12}.nnue"
-      $dummy = $nnuenet -match "(?<nnuenet>nn-[a-z0-9]{12}.nnue)"
-      $nnuenet = $Matches.nnuenet
-      Write-Host "Default net:" $nnuenet
-      $nnuedownloadurl = "https://tests.stockfishchess.org/api/nn/$nnuenet"
-      $nnuefilepath = "src\${env:CONFIGURATION}\$nnuenet"
-      if (Test-Path -Path $nnuefilepath) {
-            Write-Host "Already available."
-      } else {
-            Write-Host "Downloading $nnuedownloadurl to $nnuefilepath"
-            Invoke-WebRequest -Uri $nnuedownloadurl -OutFile $nnuefilepath
-      }
-
-before_test:
-  - cd src/%CONFIGURATION%
-  - stockfish bench 2> out.txt >NUL
-  - ps: |
-      # Verify bench number
-      $s = (gc "./out.txt" | out-string)
-      $r = ($s -match 'Nodes searched \D+(\d+)' | % { $matches[1] })
-      Write-Host "Engine bench:" $r
-      Write-Host "Reference bench:" $bench
-      If ($r -ne $bench) { exit 1 }

src/Makefile

@@ -1,5 +1,5 @@
 # Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-# Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+# Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 #
 # Stockfish is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,11 +19,29 @@
 ### Section 1. General Configuration
 ### ==========================================================================
 
+### Establish the operating system name
+KERNEL = $(shell uname -s)
+ifeq ($(KERNEL),Linux)
+	OS = $(shell uname -o)
+endif
+
+### Target Windows OS
+ifeq ($(OS),Windows_NT)
+	ifneq ($(COMP),ndk)
+		target_windows = yes
+	endif
+else ifeq ($(COMP),mingw)
+	target_windows = yes
+	ifeq ($(WINE_PATH),)
+		WINE_PATH = $(shell which wine)
+	endif
+endif
+
 ### Executable name
-ifeq ($(COMP),mingw)
+ifeq ($(target_windows),yes)
-EXE = stockfish.exe
+	EXE = stockfish.exe
 else
-EXE = stockfish
+	EXE = stockfish
 endif
 
 ### Installation dir definitions
@@ -31,24 +49,22 @@ PREFIX = /usr/local
 BINDIR = $(PREFIX)/bin
 
 ### Built-in benchmark for pgo-builds
-PGOBENCH = ./$(EXE) bench
+ifeq ($(SDE_PATH),)
+	PGOBENCH = $(WINE_PATH) ./$(EXE) bench
+else
+	PGOBENCH = $(SDE_PATH) -- $(WINE_PATH) ./$(EXE) bench
+endif
 
 ### Source and object files
 SRCS = benchmark.cpp bitbase.cpp bitboard.cpp endgame.cpp evaluate.cpp main.cpp \
 	material.cpp misc.cpp movegen.cpp movepick.cpp pawns.cpp position.cpp psqt.cpp \
 	search.cpp thread.cpp timeman.cpp tt.cpp uci.cpp ucioption.cpp tune.cpp syzygy/tbprobe.cpp \
-	nnue/evaluate_nnue.cpp nnue/features/half_kp.cpp
+	nnue/evaluate_nnue.cpp nnue/features/half_ka_v2_hm.cpp
 
 OBJS = $(notdir $(SRCS:.cpp=.o))
 
 VPATH = syzygy:nnue:nnue/features
 
-### Establish the operating system name
-KERNEL = $(shell uname -s)
-ifeq ($(KERNEL),Linux)
-	OS = $(shell uname -o)
-endif
-
 ### ==========================================================================
 ### Section 2. High-level Configuration
 ### ==========================================================================
@@ -57,9 +73,11 @@ endif
 # ----------------------------------------------------------------------------
 #
 # debug = yes/no      --- -DNDEBUG         --- Enable/Disable debug mode
-# sanitize = undefined/thread/no (-fsanitize )
+# sanitize = none/<sanitizer> ... (-fsanitize )
 #                     --- ( undefined )    --- enable undefined behavior checks
-#                     --- ( thread    )    --- enable threading error  checks
+#                     --- ( thread    )    --- enable threading error checks
+#                     --- ( address   )    --- enable memory access checks
+#                     --- ...etc...        --- see compiler documentation for supported sanitizers
 # optimize = yes/no   --- (-O3/-fast etc.) --- Enable/Disable optimizations
 # arch = (name)       --- (-arch)          --- Target architecture
 # bits = 64/32        --- -DIS_64BIT       --- 64-/32-bit operating system
@@ -72,6 +90,7 @@ endif
 # ssse3 = yes/no      --- -mssse3          --- Use Intel Supplemental Streaming SIMD Extensions 3
 # sse41 = yes/no      --- -msse4.1         --- Use Intel Streaming SIMD Extensions 4.1
 # avx2 = yes/no       --- -mavx2           --- Use Intel Advanced Vector Extensions 2
+# avxvnni = yes/no    --- -mavxvnni        --- Use Intel Vector Neural Network Instructions AVX
 # avx512 = yes/no     --- -mavx512bw       --- Use Intel Advanced Vector Extensions 512
 # vnni256 = yes/no    --- -mavx512vnni     --- Use Intel Vector Neural Network Instructions 256
 # vnni512 = yes/no    --- -mavx512vnni     --- Use Intel Vector Neural Network Instructions 512
@@ -80,6 +99,10 @@ endif
 # Note that Makefile is space sensitive, so when adding new architectures
 # or modifying existing flags, you have to make sure there are no extra spaces
 # at the end of the line for flag values.
+#
+# Example of use for these flags:
+# make build ARCH=x86-64-avx512 debug=yes sanitize="address undefined"
+
 
 ### 2.1. General and architecture defaults
 
@@ -90,9 +113,9 @@ endif
 # explicitly check for the list of supported architectures (as listed with make help),
 # the user can override with `make ARCH=x86-32-vnni256 SUPPORTED_ARCH=true`
 ifeq ($(ARCH), $(filter $(ARCH), \
-                 x86-64-vnni512 x86-64-vnni256 x86-64-avx512 x86-64-bmi2 x86-64-avx2 \
+                 x86-64-vnni512 x86-64-vnni256 x86-64-avx512 x86-64-avxvnni x86-64-bmi2 \
-                 x86-64-sse41-popcnt x86-64-modern x86-64-ssse3 x86-64-sse3-popcnt \
+                 x86-64-avx2 x86-64-sse41-popcnt x86-64-modern x86-64-ssse3 x86-64-sse3-popcnt \
-                 x86-64 x86-32-sse41-popcnt x86-32-sse2 x86-32 ppc-64 ppc-32 \
+                 x86-64 x86-32-sse41-popcnt x86-32-sse2 x86-32 ppc-64 ppc-32 e2k \
                  armv7 armv7-neon armv8 apple-silicon general-64 general-32))
    SUPPORTED_ARCH=true
 else
@@ -101,7 +124,7 @@ endif
 
 optimize = yes
 debug = no
-sanitize = no
+sanitize = none
 bits = 64
 prefetch = no
 popcnt = no
@@ -112,10 +135,12 @@ sse2 = no
 ssse3 = no
 sse41 = no
 avx2 = no
+avxvnni = no
 avx512 = no
 vnni256 = no
 vnni512 = no
 neon = no
+arm_version = 0
 STRIP = strip
 
 ### 2.2 Architecture specific
@@ -127,7 +152,7 @@ ifeq ($(findstring x86,$(ARCH)),x86)
 ifeq ($(findstring x86-32,$(ARCH)),x86-32)
 	arch = i386
 	bits = 32
-	sse = yes
+	sse = no
 	mmx = yes
 else
 	arch = x86_64
@@ -182,6 +207,17 @@ ifeq ($(findstring -avx2,$(ARCH)),-avx2)
 	avx2 = yes
 endif
 
+ifeq ($(findstring -avxvnni,$(ARCH)),-avxvnni)
+	popcnt = yes
+	sse = yes
+	sse2 = yes
+	ssse3 = yes
+	sse41 = yes
+	avx2 = yes
+	avxvnni = yes
+	pext = yes
+endif
+
 ifeq ($(findstring -bmi2,$(ARCH)),-bmi2)
 	popcnt = yes
 	sse = yes
@@ -252,6 +288,7 @@ ifeq ($(ARCH),armv7)
 	arch = armv7
 	prefetch = yes
 	bits = 32
+	arm_version = 7
 endif
 
 ifeq ($(ARCH),armv7-neon)
@@ -260,6 +297,7 @@ ifeq ($(ARCH),armv7-neon)
 	popcnt = yes
 	neon = yes
 	bits = 32
+	arm_version = 7
 endif
 
 ifeq ($(ARCH),armv8)
@@ -267,6 +305,7 @@ ifeq ($(ARCH),armv8)
 	prefetch = yes
 	popcnt = yes
 	neon = yes
+	arm_version = 8
 endif
 
 ifeq ($(ARCH),apple-silicon)
@@ -274,6 +313,7 @@ ifeq ($(ARCH),apple-silicon)
 	prefetch = yes
 	popcnt = yes
 	neon = yes
+	arm_version = 8
 endif
 
 ifeq ($(ARCH),ppc-32)
@@ -287,6 +327,17 @@ ifeq ($(ARCH),ppc-64)
 	prefetch = yes
 endif
 
+ifeq ($(findstring e2k,$(ARCH)),e2k)
+	arch = e2k
+	mmx = yes
+	bits = 64
+	sse = yes
+	sse2 = yes
+	ssse3 = yes
+	sse41 = yes
+	popcnt = yes
+endif
+
 endif
 
 ### ==========================================================================
@@ -326,29 +377,27 @@ ifeq ($(COMP),gcc)
 	endif
 endif
 
+ifeq ($(target_windows),yes)
+	LDFLAGS += -static
+endif
+
 ifeq ($(COMP),mingw)
 	comp=mingw
 
-	ifeq ($(KERNEL),Linux)
+	ifeq ($(bits),64)
-		ifeq ($(bits),64)
+		ifeq ($(shell which x86_64-w64-mingw32-c++-posix 2> /dev/null),)
-			ifeq ($(shell which x86_64-w64-mingw32-c++-posix),)
+			CXX=x86_64-w64-mingw32-c++
-				CXX=x86_64-w64-mingw32-c++
-			else
-				CXX=x86_64-w64-mingw32-c++-posix
-			endif
 		else
-			ifeq ($(shell which i686-w64-mingw32-c++-posix),)
+			CXX=x86_64-w64-mingw32-c++-posix
-				CXX=i686-w64-mingw32-c++
-			else
-				CXX=i686-w64-mingw32-c++-posix
-			endif
 		endif
 	else
-		CXX=g++
+		ifeq ($(shell which i686-w64-mingw32-c++-posix 2> /dev/null),)
+			CXX=i686-w64-mingw32-c++
+		else
+			CXX=i686-w64-mingw32-c++-posix
+		endif
 	endif
-
+	CXXFLAGS += -pedantic -Wextra -Wshadow
-	CXXFLAGS += -Wextra -Wshadow
-	LDFLAGS += -static
 endif
 
 ifeq ($(COMP),icc)
@@ -360,11 +409,15 @@ endif
 ifeq ($(COMP),clang)
 	comp=clang
 	CXX=clang++
+	ifeq ($(target_windows),yes)
+		CXX=x86_64-w64-mingw32-clang++
+	endif
+
 	CXXFLAGS += -pedantic -Wextra -Wshadow
 
-	ifneq ($(KERNEL),Darwin)
+	ifeq ($(filter $(KERNEL),Darwin OpenBSD FreeBSD),)
-	ifneq ($(KERNEL),OpenBSD)
+	ifeq ($(target_windows),)
-	ifneq ($(KERNEL),FreeBSD)
+	ifneq ($(RTLIB),compiler-rt)
 		LDFLAGS += -latomic
 	endif
 	endif
@@ -382,8 +435,12 @@ ifeq ($(COMP),clang)
 endif
 
 ifeq ($(KERNEL),Darwin)
-	CXXFLAGS += -arch $(arch) -mmacosx-version-min=10.14
+	CXXFLAGS += -mmacosx-version-min=10.14
-	LDFLAGS += -arch $(arch) -mmacosx-version-min=10.14
+	LDFLAGS += -mmacosx-version-min=10.14
+	ifneq ($(arch),any)
+		CXXFLAGS += -arch $(arch)
+		LDFLAGS += -arch $(arch)
+	endif
 	XCRUN = xcrun
 endif
 
@@ -396,11 +453,19 @@ ifeq ($(COMP),ndk)
 	ifeq ($(arch),armv7)
 		CXX=armv7a-linux-androideabi16-clang++
 		CXXFLAGS += -mthumb -march=armv7-a -mfloat-abi=softfp -mfpu=neon
-		STRIP=arm-linux-androideabi-strip
+		ifneq ($(shell which arm-linux-androideabi-strip 2>/dev/null),)
+			STRIP=arm-linux-androideabi-strip
+		else
+			STRIP=llvm-strip
+		endif
 	endif
 	ifeq ($(arch),armv8)
 		CXX=aarch64-linux-android21-clang++
-		STRIP=aarch64-linux-android-strip
+		ifneq ($(shell which aarch64-linux-android-strip 2>/dev/null),)
+			STRIP=aarch64-linux-android-strip
+		else
+			STRIP=llvm-strip
+		endif
 	endif
 	LDFLAGS += -static-libstdc++ -pie -lm -latomic
 endif
@@ -414,6 +479,9 @@ else ifeq ($(comp),clang)
 else
 	profile_make = gcc-profile-make
 	profile_use = gcc-profile-use
+	ifeq ($(KERNEL),Darwin)
+		EXTRAPROFILEFLAGS = -fvisibility=hidden
+	endif
 endif
 
 ### Travis CI script uses COMPILER to overwrite CXX
@@ -458,9 +526,9 @@ else
 endif
 
 ### 3.2.2 Debugging with undefined behavior sanitizers
-ifneq ($(sanitize),no)
+ifneq ($(sanitize),none)
-        CXXFLAGS += -g3 -fsanitize=$(sanitize)
+        CXXFLAGS += -g3 $(addprefix -fsanitize=,$(sanitize))
-        LDFLAGS += -fsanitize=$(sanitize)
+        LDFLAGS += $(addprefix -fsanitize=,$(sanitize))
 endif
 
 ### 3.3 Optimization
@@ -474,11 +542,17 @@ ifeq ($(optimize),yes)
 		endif
 	endif
 
-	ifeq ($(comp),$(filter $(comp),gcc clang icc))
+    ifeq ($(KERNEL),Darwin)
-		ifeq ($(KERNEL),Darwin)
+        ifeq ($(comp),$(filter $(comp),clang icc))
-			CXXFLAGS += -mdynamic-no-pic
+            CXXFLAGS += -mdynamic-no-pic
-		endif
+        endif
-	endif
+
+        ifeq ($(comp),gcc)
+            ifneq ($(arch),arm64)
+                CXXFLAGS += -mdynamic-no-pic
+            endif
+        endif
+    endif
 
 	ifeq ($(comp),clang)
 		CXXFLAGS += -fexperimental-new-pass-manager
@@ -490,7 +564,7 @@ ifeq ($(bits),64)
 	CXXFLAGS += -DIS_64BIT
 endif
 
-### 3.5 prefetch
+### 3.5 prefetch and popcount
 ifeq ($(prefetch),yes)
 	ifeq ($(sse),yes)
 		CXXFLAGS += -msse
@@ -499,7 +573,6 @@ else
 	CXXFLAGS += -DNO_PREFETCH
 endif
 
-### 3.6 popcnt
 ifeq ($(popcnt),yes)
 	ifeq ($(arch),$(filter $(arch),ppc64 armv7 armv8 arm64))
 		CXXFLAGS += -DUSE_POPCNT
@@ -510,7 +583,7 @@ ifeq ($(popcnt),yes)
 	endif
 endif
 
-
+### 3.6 SIMD architectures
 ifeq ($(avx2),yes)
 	CXXFLAGS += -DUSE_AVX2
 	ifeq ($(comp),$(filter $(comp),gcc clang mingw))
@@ -518,6 +591,13 @@ ifeq ($(avx2),yes)
 	endif
 endif
 
+ifeq ($(avxvnni),yes)
+	CXXFLAGS += -DUSE_VNNI -DUSE_AVXVNNI
+	ifeq ($(comp),$(filter $(comp),gcc clang mingw))
+		CXXFLAGS += -mavxvnni
+	endif
+endif
+
 ifeq ($(avx512),yes)
 	CXXFLAGS += -DUSE_AVX512
 	ifeq ($(comp),$(filter $(comp),gcc clang mingw))
@@ -568,7 +648,7 @@ ifeq ($(mmx),yes)
 endif
 
 ifeq ($(neon),yes)
-	CXXFLAGS += -DUSE_NEON
+	CXXFLAGS += -DUSE_NEON=$(arm_version)
 	ifeq ($(KERNEL),Linux)
 	ifneq ($(COMP),ndk)
 	ifneq ($(arch),armv8)
@@ -593,9 +673,7 @@ ifeq ($(optimize),yes)
 ifeq ($(debug), no)
 	ifeq ($(comp),clang)
 		CXXFLAGS += -flto
-		ifneq ($(findstring MINGW,$(KERNEL)),)
+		ifeq ($(target_windows),yes)
-			CXXFLAGS += -fuse-ld=lld
-		else ifneq ($(findstring MSYS,$(KERNEL)),)
 			CXXFLAGS += -fuse-ld=lld
 		endif
 		LDFLAGS += $(CXXFLAGS)
@@ -606,25 +684,17 @@ ifeq ($(debug), no)
 	ifeq ($(gccisclang),)
 		CXXFLAGS += -flto
 		LDFLAGS += $(CXXFLAGS) -flto=jobserver
-		ifneq ($(findstring MINGW,$(KERNEL)),)
-			LDFLAGS += -save-temps
-		else ifneq ($(findstring MSYS,$(KERNEL)),)
-			LDFLAGS += -save-temps
-		endif
 	else
 		CXXFLAGS += -flto
 		LDFLAGS += $(CXXFLAGS)
 	endif
 
-# To use LTO and static linking on windows, the tool chain requires a recent gcc:
+# To use LTO and static linking on Windows,
-# gcc version 10.1 in msys2 or TDM-GCC version 9.2 are known to work, older might not.
+# the tool chain requires gcc version 10.1 or later.
-# So, only enable it for a cross from Linux by default.
 	else ifeq ($(comp),mingw)
-	ifeq ($(KERNEL),Linux)
 	ifneq ($(arch),i386)
 		CXXFLAGS += -flto
-		LDFLAGS += $(CXXFLAGS) -flto=jobserver
+		LDFLAGS += $(CXXFLAGS) -save-temps
-	endif
 	endif
 	endif
 endif
@@ -663,6 +733,7 @@ help:
 	@echo "x86-64-vnni512          > x86 64-bit with vnni support 512bit wide"
 	@echo "x86-64-vnni256          > x86 64-bit with vnni support 256bit wide"
 	@echo "x86-64-avx512           > x86 64-bit with avx512 support"
+	@echo "x86-64-avxvnni          > x86 64-bit with avxvnni support"
 	@echo "x86-64-bmi2             > x86 64-bit with bmi2 support"
 	@echo "x86-64-avx2             > x86 64-bit with avx2 support"
 	@echo "x86-64-sse41-popcnt     > x86 64-bit with sse41 and popcnt support"
@@ -678,6 +749,7 @@ help:
 	@echo "armv7                   > ARMv7 32-bit"
 	@echo "armv7-neon              > ARMv7 32-bit with popcnt and neon"
 	@echo "armv8                   > ARMv8 64-bit with popcnt and neon"
+	@echo "e2k                     > Elbrus 2000"
 	@echo "apple-silicon           > Apple silicon ARM64"
 	@echo "general-64              > unspecified 64-bit"
 	@echo "general-32              > unspecified 32-bit"
@@ -724,7 +796,7 @@ profile-build: net config-sanity objclean profileclean
 	$(MAKE) ARCH=$(ARCH) COMP=$(COMP) $(profile_make)
 	@echo ""
 	@echo "Step 2/4. Running benchmark for pgo-build ..."
-	$(PGOBENCH) > /dev/null
+	$(PGOBENCH) 2>&1 | tail -n 4
 	@echo ""
 	@echo "Step 3/4. Building optimized executable ..."
 	$(MAKE) ARCH=$(ARCH) COMP=$(COMP) objclean
@@ -739,7 +811,7 @@ strip:
 install:
 	-mkdir -p -m 755 $(BINDIR)
 	-cp $(EXE) $(BINDIR)
-	-strip $(BINDIR)/$(EXE)
+	$(STRIP) $(BINDIR)/$(EXE)
 
 # clean all
 clean: objclean profileclean
@@ -771,13 +843,17 @@ net:
 
 # clean binaries and objects
 objclean:
-	@rm -f $(EXE) *.o ./syzygy/*.o ./nnue/*.o ./nnue/features/*.o
+	@rm -f stockfish stockfish.exe *.o ./syzygy/*.o ./nnue/*.o ./nnue/features/*.o
 
 # clean auxiliary profiling files
 profileclean:
 	@rm -rf profdir
 	@rm -f bench.txt *.gcda *.gcno ./syzygy/*.gcda ./nnue/*.gcda ./nnue/features/*.gcda *.s
 	@rm -f stockfish.profdata *.profraw
+	@rm -f stockfish.*args*
+	@rm -f stockfish.*lt*
+	@rm -f stockfish.res
+	@rm -f ./-lstdc++.res
 
 default:
 	help
@@ -807,10 +883,12 @@ config-sanity: net
 	@echo "ssse3: '$(ssse3)'"
 	@echo "sse41: '$(sse41)'"
 	@echo "avx2: '$(avx2)'"
+	@echo "avxvnni: '$(avxvnni)'"
 	@echo "avx512: '$(avx512)'"
 	@echo "vnni256: '$(vnni256)'"
 	@echo "vnni512: '$(vnni512)'"
 	@echo "neon: '$(neon)'"
+	@echo "arm_version: '$(arm_version)'"
 	@echo ""
 	@echo "Flags:"
 	@echo "CXX: $(CXX)"
@@ -820,11 +898,10 @@ config-sanity: net
 	@echo "Testing config sanity. If this fails, try 'make help' ..."
 	@echo ""
 	@test "$(debug)" = "yes" || test "$(debug)" = "no"
-	@test "$(sanitize)" = "undefined" || test "$(sanitize)" = "thread" || test "$(sanitize)" = "address" || test "$(sanitize)" = "no"
 	@test "$(optimize)" = "yes" || test "$(optimize)" = "no"
 	@test "$(SUPPORTED_ARCH)" = "true"
 	@test "$(arch)" = "any" || test "$(arch)" = "x86_64" || test "$(arch)" = "i386" || \
-	 test "$(arch)" = "ppc64" || test "$(arch)" = "ppc" || \
+	 test "$(arch)" = "ppc64" || test "$(arch)" = "ppc" || test "$(arch)" = "e2k" || \
 	 test "$(arch)" = "armv7" || test "$(arch)" = "armv8" || test "$(arch)" = "arm64"
 	@test "$(bits)" = "32" || test "$(bits)" = "64"
 	@test "$(prefetch)" = "yes" || test "$(prefetch)" = "no"
@@ -860,14 +937,17 @@ clang-profile-use:
 	all
 
 gcc-profile-make:
+	@mkdir -p profdir
 	$(MAKE) ARCH=$(ARCH) COMP=$(COMP) \
-	EXTRACXXFLAGS='-fprofile-generate' \
+	EXTRACXXFLAGS='-fprofile-generate=profdir' \
+	EXTRACXXFLAGS+=$(EXTRAPROFILEFLAGS) \
 	EXTRALDFLAGS='-lgcov' \
 	all
 
 gcc-profile-use:
 	$(MAKE) ARCH=$(ARCH) COMP=$(COMP) \
-	EXTRACXXFLAGS='-fprofile-use -fno-peel-loops -fno-tracer' \
+	EXTRACXXFLAGS='-fprofile-use=profdir -fno-peel-loops -fno-tracer' \
+	EXTRACXXFLAGS+=$(EXTRAPROFILEFLAGS) \
 	EXTRALDFLAGS='-lgcov' \
 	all
 
@@ -882,7 +962,7 @@ icc-profile-use:
 	EXTRACXXFLAGS='-prof_use -prof_dir ./profdir' \
 	all
 
-.depend:
+.depend: $(SRCS)
 	-@$(CXX) $(DEPENDFLAGS) -MM $(SRCS) > $@ 2> /dev/null
 
 -include .depend

src/benchmark.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -87,11 +87,14 @@ const vector<string> Defaults = {
   // Chess 960
   "setoption name UCI_Chess960 value true",
   "bbqnnrkr/pppppppp/8/8/8/8/PPPPPPPP/BBQNNRKR w HFhf - 0 1 moves g2g3 d7d5 d2d4 c8h3 c1g5 e8d6 g5e7 f7f6",
+  "nqbnrkrb/pppppppp/8/8/8/8/PPPPPPPP/NQBNRKRB w KQkq - 0 1",
   "setoption name UCI_Chess960 value false"
 };
 
 } // namespace
 
+namespace Stockfish {
+
 /// setup_bench() builds a list of UCI commands to be run by bench. There
 /// are five parameters: TT size in MB, number of search threads that
 /// should be used, the limit value spent for each position, a file name
@@ -168,3 +171,5 @@ vector<string> setup_bench(const Position& current, istream& is) {
 
   return list;
 }
+
+} // namespace Stockfish

src/bitbase.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -23,6 +23,8 @@
 #include "bitboard.h"
 #include "types.h"
 
+namespace Stockfish {
+
 namespace {
 
   // There are 24 possible pawn squares: files A to D and ranks from 2 to 7.
@@ -66,7 +68,6 @@ namespace {
 
 } // namespace
 
-
 bool Bitbases::probe(Square wksq, Square wpsq, Square bksq, Color stm) {
 
   assert(file_of(wpsq) <= FILE_D);
@@ -96,7 +97,6 @@ void Bitbases::init() {
           KPKBitbase.set(idx);
 }
 
-
 namespace {
 
   KPKPosition::KPKPosition(unsigned idx) {
@@ -150,8 +150,8 @@ namespace {
     Bitboard b = attacks_bb<KING>(ksq[stm]);
 
     while (b)
-        r |= stm == WHITE ? db[index(BLACK, ksq[BLACK] , pop_lsb(&b), psq)]
+        r |= stm == WHITE ? db[index(BLACK, ksq[BLACK], pop_lsb(b), psq)]
-                          : db[index(WHITE, pop_lsb(&b),  ksq[WHITE], psq)];
+                          : db[index(WHITE, pop_lsb(b), ksq[WHITE], psq)];
 
     if (stm == WHITE)
     {
@@ -168,3 +168,5 @@ namespace {
   }
 
 } // namespace
+
+} // namespace Stockfish

src/bitboard.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -22,11 +22,14 @@
 #include "bitboard.h"
 #include "misc.h"
 
+namespace Stockfish {
+
 uint8_t PopCnt16[1 << 16];
 uint8_t SquareDistance[SQUARE_NB][SQUARE_NB];
 
 Bitboard SquareBB[SQUARE_NB];
 Bitboard LineBB[SQUARE_NB][SQUARE_NB];
+Bitboard BetweenBB[SQUARE_NB][SQUARE_NB];
 Bitboard PseudoAttacks[PIECE_TYPE_NB][SQUARE_NB];
 Bitboard PawnAttacks[COLOR_NB][SQUARE_NB];
 
@@ -42,7 +45,6 @@ namespace {
 
 }
 
-
 /// safe_destination() returns the bitboard of target square for the given step
 /// from the given square. If the step is off the board, returns empty bitboard.
 
@@ -55,7 +57,7 @@ inline Bitboard safe_destination(Square s, int step) {
 /// Bitboards::pretty() returns an ASCII representation of a bitboard suitable
 /// to be printed to standard output. Useful for debugging.
 
-const std::string Bitboards::pretty(Bitboard b) {
+std::string Bitboards::pretty(Bitboard b) {
 
   std::string s = "+---+---+---+---+---+---+---+---+\n";
 
@@ -106,12 +108,17 @@ void Bitboards::init() {
 
       for (PieceType pt : { BISHOP, ROOK })
           for (Square s2 = SQ_A1; s2 <= SQ_H8; ++s2)
+          {
               if (PseudoAttacks[pt][s1] & s2)
-                  LineBB[s1][s2] = (attacks_bb(pt, s1, 0) & attacks_bb(pt, s2, 0)) | s1 | s2;
+              {
+                  LineBB[s1][s2]    = (attacks_bb(pt, s1, 0) & attacks_bb(pt, s2, 0)) | s1 | s2;
+                  BetweenBB[s1][s2] = (attacks_bb(pt, s1, square_bb(s2)) & attacks_bb(pt, s2, square_bb(s1)));
+              }
+              BetweenBB[s1][s2] |= s2;
+          }
   }
 }
 
-
 namespace {
 
   Bitboard sliding_attack(PieceType pt, Square sq, Bitboard occupied) {
@@ -123,7 +130,7 @@ namespace {
     for (Direction d : (pt == ROOK ? RookDirections : BishopDirections))
     {
         Square s = sq;
-        while(safe_destination(s, d) && !(occupied & s))
+        while (safe_destination(s, d) && !(occupied & s))
             attacks |= (s += d);
     }
 
@@ -211,3 +218,5 @@ namespace {
     }
   }
 }
+
+} // namespace Stockfish

src/bitboard.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -23,19 +23,21 @@
 
 #include "types.h"
 
+namespace Stockfish {
+
 namespace Bitbases {
 
 void init();
 bool probe(Square wksq, Square wpsq, Square bksq, Color us);
 
-}
+} // namespace Stockfish::Bitbases
 
 namespace Bitboards {
 
 void init();
-const std::string pretty(Bitboard b);
+std::string pretty(Bitboard b);
 
-}
+} // namespace Stockfish::Bitboards
 
 constexpr Bitboard AllSquares = ~Bitboard(0);
 constexpr Bitboard DarkSquares = 0xAA55AA55AA55AA55ULL;
@@ -73,6 +75,7 @@ extern uint8_t PopCnt16[1 << 16];
 extern uint8_t SquareDistance[SQUARE_NB][SQUARE_NB];
 
 extern Bitboard SquareBB[SQUARE_NB];
+extern Bitboard BetweenBB[SQUARE_NB][SQUARE_NB];
 extern Bitboard LineBB[SQUARE_NB][SQUARE_NB];
 extern Bitboard PseudoAttacks[PIECE_TYPE_NB][SQUARE_NB];
 extern Bitboard PawnAttacks[COLOR_NB][SQUARE_NB];
@@ -209,23 +212,29 @@ constexpr Bitboard adjacent_files_bb(Square s) {
 inline Bitboard line_bb(Square s1, Square s2) {
 
   assert(is_ok(s1) && is_ok(s2));
+
   return LineBB[s1][s2];
 }
 
 
-/// between_bb() returns a bitboard representing squares that are linearly
+/// between_bb(s1, s2) returns a bitboard representing the squares in the semi-open
-/// between the two given squares (excluding the given squares). If the given
+/// segment between the squares s1 and s2 (excluding s1 but including s2). If the
-/// squares are not on a same file/rank/diagonal, we return 0. For instance,
+/// given squares are not on a same file/rank/diagonal, it returns s2. For instance,
-/// between_bb(SQ_C4, SQ_F7) will return a bitboard with squares D5 and E6.
+/// between_bb(SQ_C4, SQ_F7) will return a bitboard with squares D5, E6 and F7, but
+/// between_bb(SQ_E6, SQ_F8) will return a bitboard with the square F8. This trick
+/// allows to generate non-king evasion moves faster: the defending piece must either
+/// interpose itself to cover the check or capture the checking piece.
 
 inline Bitboard between_bb(Square s1, Square s2) {
-  Bitboard b = line_bb(s1, s2) & ((AllSquares << s1) ^ (AllSquares << s2));
+
-  return b & (b - 1); //exclude lsb
+  assert(is_ok(s1) && is_ok(s2));
+
+  return BetweenBB[s1][s2];
 }
 
 
-/// forward_ranks_bb() returns a bitboard representing the squares on the ranks
+/// forward_ranks_bb() returns a bitboard representing the squares on the ranks in
-/// in front of the given one, from the point of view of the given color. For instance,
+/// front of the given one, from the point of view of the given color. For instance,
 /// forward_ranks_bb(BLACK, SQ_D3) will return the 16 squares on ranks 1 and 2.
 
 constexpr Bitboard forward_ranks_bb(Color c, Square s) {
@@ -412,13 +421,20 @@ inline Square msb(Bitboard b) {
 
 #endif
 
+/// least_significant_square_bb() returns the bitboard of the least significant
+/// square of a non-zero bitboard. It is equivalent to square_bb(lsb(bb)).
+
+inline Bitboard least_significant_square_bb(Bitboard b) {
+  assert(b);
+  return b & -b;
+}
 
 /// pop_lsb() finds and clears the least significant bit in a non-zero bitboard
 
-inline Square pop_lsb(Bitboard* b) {
+inline Square pop_lsb(Bitboard& b) {
-  assert(*b);
+  assert(b);
-  const Square s = lsb(*b);
+  const Square s = lsb(b);
-  *b &= *b - 1;
+  b &= b - 1;
   return s;
 }
 
@@ -430,4 +446,6 @@ inline Square frontmost_sq(Color c, Bitboard b) {
   return c == WHITE ? msb(b) : lsb(b);
 }
 
+} // namespace Stockfish
+
 #endif // #ifndef BITBOARD_H_INCLUDED

src/endgame.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -22,6 +22,8 @@
 #include "endgame.h"
 #include "movegen.h"
 
+namespace Stockfish {
+
 namespace {
 
   // Used to drive the king towards the edge of the board
@@ -741,3 +743,5 @@ ScaleFactor Endgame<KPKP>::operator()(const Position& pos) const {
   // it's probably at least a draw even with the pawn.
   return Bitbases::probe(strongKing, strongPawn, weakKing, us) ? SCALE_FACTOR_NONE : SCALE_FACTOR_DRAW;
 }
+
+} // namespace Stockfish

src/endgame.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -28,6 +28,7 @@
 #include "position.h"
 #include "types.h"
 
+namespace Stockfish {
 
 /// EndgameCode lists all supported endgame functions by corresponding codes
 
@@ -120,4 +121,6 @@ namespace Endgames {
   }
 }
 
+} // namespace Stockfish
+
 #endif // #ifndef ENDGAME_H_INCLUDED

src/evaluate.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -33,6 +33,7 @@
 #include "misc.h"
 #include "pawns.h"
 #include "thread.h"
+#include "timeman.h"
 #include "uci.h"
 #include "incbin/incbin.h"
 
@@ -54,12 +55,13 @@
 
 
 using namespace std;
-using namespace Eval::NNUE;
+
+namespace Stockfish {
 
 namespace Eval {
 
   bool useNNUE;
-  string eval_file_loaded = "None";
+  string currentEvalFileName = "None";
 
   /// NNUE::init() tries to load a NNUE network at startup time, or when the engine
   /// receives a UCI command "setoption name EvalFile value nn-[a-z0-9]{12}.nnue"
@@ -76,6 +78,8 @@ namespace Eval {
         return;
 
     string eval_file = string(Options["EvalFile"]);
+    if (eval_file.empty())
+        eval_file = EvalFileDefaultName;
 
     #if defined(DEFAULT_NNUE_DIRECTORY)
     #define stringify2(x) #x
@@ -86,13 +90,13 @@ namespace Eval {
     #endif
 
     for (string directory : dirs)
-        if (eval_file_loaded != eval_file)
+        if (currentEvalFileName != eval_file)
         {
             if (directory != "<internal>")
             {
                 ifstream stream(directory + eval_file, ios::binary);
                 if (load_eval(eval_file, stream))
-                    eval_file_loaded = eval_file;
+                    currentEvalFileName = eval_file;
             }
 
             if (directory == "<internal>" && eval_file == EvalFileDefaultName)
@@ -104,10 +108,11 @@ namespace Eval {
 
                 MemoryBuffer buffer(const_cast<char*>(reinterpret_cast<const char*>(gEmbeddedNNUEData)),
                                     size_t(gEmbeddedNNUESize));
+                (void) gEmbeddedNNUEEnd; // Silence warning on unused variable
 
                 istream stream(&buffer);
                 if (load_eval(eval_file, stream))
-                    eval_file_loaded = eval_file;
+                    currentEvalFileName = eval_file;
             }
         }
   }
@@ -116,16 +121,16 @@ namespace Eval {
   void NNUE::verify() {
 
     string eval_file = string(Options["EvalFile"]);
+    if (eval_file.empty())
+        eval_file = EvalFileDefaultName;
 
-    if (useNNUE && eval_file_loaded != eval_file)
+    if (useNNUE && currentEvalFileName != eval_file)
     {
-        UCI::OptionsMap defaults;
-        UCI::init(defaults);
 
         string msg1 = "If the UCI option \"Use NNUE\" is set to true, network evaluation parameters compatible with the engine must be available.";
         string msg2 = "The option is set to true, but the network file " + eval_file + " was not loaded successfully.";
         string msg3 = "The UCI option EvalFile might need to specify the full path, including the directory name, to the network file.";
-        string msg4 = "The default net can be downloaded from: https://tests.stockfishchess.org/api/nn/" + string(defaults["EvalFile"]);
+        string msg4 = "The default net can be downloaded from: https://tests.stockfishchess.org/api/nn/" + std::string(EvalFileDefaultName);
         string msg5 = "The engine will be terminated now.";
 
         sync_cout << "info string ERROR: " << msg1 << sync_endl;
@@ -178,7 +183,7 @@ namespace Trace {
     else
         os << scores[t][WHITE] << " | " << scores[t][BLACK];
 
-    os << " | " << scores[t][WHITE] - scores[t][BLACK] << "\n";
+    os << " | " << scores[t][WHITE] - scores[t][BLACK] << " |\n";
     return os;
   }
 }
@@ -188,11 +193,9 @@ using namespace Trace;
 namespace {
 
   // Threshold for lazy and space evaluation
-  constexpr Value LazyThreshold1 =  Value(1565);
+  constexpr Value LazyThreshold1    =  Value(3631);
-  constexpr Value LazyThreshold2 =  Value(1102);
+  constexpr Value LazyThreshold2    =  Value(2084);
-  constexpr Value SpaceThreshold = Value(11551);
+  constexpr Value SpaceThreshold    =  Value(11551);
-  constexpr Value NNUEThreshold1 =   Value(682);
-  constexpr Value NNUEThreshold2 =   Value(176);
 
   // KingAttackWeights[PieceType] contains king attack weights by piece type
   constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 81, 52, 44, 10 };
@@ -255,11 +258,12 @@ namespace {
     S(0, 0), S(3, 44), S(37, 68), S(42, 60), S(0, 39), S(58, 43)
   };
 
+  constexpr Value CorneredBishop = Value(50);
+
   // Assorted bonuses and penalties
   constexpr Score UncontestedOutpost  = S(  1, 10);
   constexpr Score BishopOnKingRing    = S( 24,  0);
   constexpr Score BishopXRayPawns     = S(  4,  5);
-  constexpr Score CorneredBishop      = S( 50, 50);
   constexpr Score FlankAttacks        = S(  8,  0);
   constexpr Score Hanging             = S( 69, 36);
   constexpr Score KnightOnQueen       = S( 16, 11);
@@ -394,8 +398,9 @@ namespace {
 
     attackedBy[Us][Pt] = 0;
 
-    while (b1) {
+    while (b1)
-        Square s = pop_lsb(&b1);
+    {
+        Square s = pop_lsb(b1);
 
         // Find attacked squares, including x-ray attacks for bishops and rooks
         b = Pt == BISHOP ? attacks_bb<BISHOP>(s, pos.pieces() ^ pos.pieces(QUEEN))
@@ -475,9 +480,8 @@ namespace {
                 {
                     Direction d = pawn_push(Us) + (file_of(s) == FILE_A ? EAST : WEST);
                     if (pos.piece_on(s + d) == make_piece(Us, PAWN))
-                        score -= !pos.empty(s + d + pawn_push(Us))                ? CorneredBishop * 4
+                        score -= !pos.empty(s + d + pawn_push(Us)) ? 4 * make_score(CorneredBishop, CorneredBishop)
-                                : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? CorneredBishop * 2
+                                                                   : 3 * make_score(CorneredBishop, CorneredBishop);
-                                                                                  : CorneredBishop;
                 }
             }
         }
@@ -656,11 +660,11 @@ namespace {
     {
         b = (defended | weak) & (attackedBy[Us][KNIGHT] | attackedBy[Us][BISHOP]);
         while (b)
-            score += ThreatByMinor[type_of(pos.piece_on(pop_lsb(&b)))];
+            score += ThreatByMinor[type_of(pos.piece_on(pop_lsb(b)))];
 
         b = weak & attackedBy[Us][ROOK];
         while (b)
-            score += ThreatByRook[type_of(pos.piece_on(pop_lsb(&b)))];
+            score += ThreatByRook[type_of(pos.piece_on(pop_lsb(b)))];
 
         if (weak & attackedBy[Us][KING])
             score += ThreatByKing;
@@ -758,7 +762,7 @@ namespace {
 
     while (b)
     {
-        Square s = pop_lsb(&b);
+        Square s = pop_lsb(b);
 
         assert(!(pos.pieces(Them, PAWN) & forward_file_bb(Us, s + Up)));
 
@@ -904,7 +908,7 @@ namespace {
     Color strongSide = eg > VALUE_DRAW ? WHITE : BLACK;
     int sf = me->scale_factor(pos, strongSide);
 
-    // If scale factor is not already specific, scale down via general heuristics
+    // If scale factor is not already specific, scale up/down via general heuristics
     if (sf == SCALE_FACTOR_NORMAL)
     {
         if (pos.opposite_bishops())
@@ -977,7 +981,7 @@ namespace {
     // Initialize score by reading the incrementally updated scores included in
     // the position object (material + piece square tables) and the material
     // imbalance. Score is computed internally from the white point of view.
-    Score score = pos.psq_score() + me->imbalance() + pos.this_thread()->contempt;
+    Score score = pos.psq_score() + me->imbalance() + pos.this_thread()->trend;
 
     // Probe the pawn hash table
     pe = Pawns::probe(pos);
@@ -985,7 +989,9 @@ namespace {
 
     // Early exit if score is high
     auto lazy_skip = [&](Value lazyThreshold) {
-        return abs(mg_value(score) + eg_value(score)) / 2 > lazyThreshold + pos.non_pawn_material() / 64;
+        return abs(mg_value(score) + eg_value(score)) >   lazyThreshold
+                                                        + std::abs(pos.this_thread()->bestValue) * 5 / 4
+                                                        + pos.non_pawn_material() / 32;
     };
 
     if (lazy_skip(LazyThreshold1))
@@ -1031,12 +1037,44 @@ make_v:
     v = (v / 16) * 16;
 
     // Side to move point of view
-    v = (pos.side_to_move() == WHITE ? v : -v) + Tempo;
+    v = (pos.side_to_move() == WHITE ? v : -v);
 
     return v;
   }
 
-} // namespace
+
+  /// Fisher Random Chess: correction for cornered bishops, to fix chess960 play with NNUE
+
+  Value fix_FRC(const Position& pos) {
+
+    constexpr Bitboard Corners =  1ULL << SQ_A1 | 1ULL << SQ_H1 | 1ULL << SQ_A8 | 1ULL << SQ_H8;
+
+    if (!(pos.pieces(BISHOP) & Corners))
+        return VALUE_ZERO;
+
+    int correction = 0;
+
+    if (   pos.piece_on(SQ_A1) == W_BISHOP
+        && pos.piece_on(SQ_B2) == W_PAWN)
+        correction -= CorneredBishop;
+
+    if (   pos.piece_on(SQ_H1) == W_BISHOP
+        && pos.piece_on(SQ_G2) == W_PAWN)
+        correction -= CorneredBishop;
+
+    if (   pos.piece_on(SQ_A8) == B_BISHOP
+        && pos.piece_on(SQ_B7) == B_PAWN)
+        correction += CorneredBishop;
+
+    if (   pos.piece_on(SQ_H8) == B_BISHOP
+        && pos.piece_on(SQ_G7) == B_PAWN)
+        correction += CorneredBishop;
+
+    return pos.side_to_move() == WHITE ?  Value(3 * correction)
+                                       : -Value(3 * correction);
+  }
+
+} // namespace Eval
 
 
 /// evaluate() is the evaluator for the outer world. It returns a static
@@ -1045,42 +1083,36 @@ make_v:
 Value Eval::evaluate(const Position& pos) {
 
   Value v;
+  bool useClassical = false;
 
-  if (!Eval::useNNUE)
+  // Deciding between classical and NNUE eval (~10 Elo): for high PSQ imbalance we use classical,
-      v = Evaluation<NO_TRACE>(pos).value();
+  // but we switch to NNUE during long shuffling or with high material on the board.
-  else
+  if (  !useNNUE
+      || abs(eg_value(pos.psq_score())) * 5 > (849 + pos.non_pawn_material() / 64) * (5 + pos.rule50_count()))
   {
-      // Scale and shift NNUE for compatibility with search and classical evaluation
+      v = Evaluation<NO_TRACE>(pos).value();          // classical
-      auto  adjusted_NNUE = [&](){
+      useClassical = abs(v) >= 298;
-         int mat = pos.non_pawn_material() + 2 * PawnValueMg * pos.count<PAWN>();
+  }
-         return NNUE::evaluate(pos) * (641 + mat / 32 - 4 * pos.rule50_count()) / 1024 + Tempo;
-      };
 
-      // If there is PSQ imbalance use classical eval, with small probability if it is small
+  // If result of a classical evaluation is much lower than threshold fall back to NNUE
-      Value psq = Value(abs(eg_value(pos.psq_score())));
+  if (useNNUE && !useClassical)
-      int   r50 = 16 + pos.rule50_count();
+  {
-      bool  largePsq = psq * 16 > (NNUEThreshold1 + pos.non_pawn_material() / 64) * r50;
+       Value nnue     = NNUE::evaluate(pos, true);     // NNUE
-      bool  classical = largePsq || (psq > PawnValueMg / 4 && !(pos.this_thread()->nodes & 0xB));
+       int scale      = 1136 + 20 * pos.non_pawn_material() / 1024;
+       Color stm      = pos.side_to_move();
+       Value optimism = pos.this_thread()->optimism[stm];
+       Value psq      = (stm == WHITE ? 1 : -1) * eg_value(pos.psq_score());
+       int complexity = 35 * abs(nnue - psq) / 256;
 
-      // Use classical evaluation for really low piece endgames.
+       optimism = optimism * (44 + complexity) / 32;
-      // The most critical case is a bishop + A/H file pawn vs naked king draw.
+       v = (nnue + optimism) * scale / 1024 - optimism;
-      bool strongClassical = pos.non_pawn_material() < 2 * RookValueMg && pos.count<PAWN>() < 2;
 
-      v = classical || strongClassical ? Evaluation<NO_TRACE>(pos).value() : adjusted_NNUE();
+       if (pos.is_chess960())
-
+           v += fix_FRC(pos);
-      // If the classical eval is small and imbalance large, use NNUE nevertheless.
-      // For the case of opposite colored bishops, switch to NNUE eval with
-      // small probability if the classical eval is less than the threshold.
-      if (   largePsq && !strongClassical
-          && (   abs(v) * 16 < NNUEThreshold2 * r50
-              || (   pos.opposite_bishops()
-                  && abs(v) * 16 < (NNUEThreshold1 + pos.non_pawn_material() / 64) * r50
-                  && !(pos.this_thread()->nodes & 0xB))))
-          v = adjusted_NNUE();
   }
 
   // Damp down the evaluation linearly when shuffling
-  v = v * (100 - pos.rule50_count()) / 100;
+  v = v * (208 - pos.rule50_count()) / 208;
 
   // Guarantee evaluation does not hit the tablebase range
   v = std::clamp(v, VALUE_TB_LOSS_IN_MAX_PLY + 1, VALUE_TB_WIN_IN_MAX_PLY - 1);
@@ -1095,7 +1127,7 @@ Value Eval::evaluate(const Position& pos) {
 /// descriptions and values of each evaluation term. Useful for debugging.
 /// Trace scores are from white's point of view
 
-std::string Eval::trace(const Position& pos) {
+std::string Eval::trace(Position& pos) {
 
   if (pos.checkers())
       return "Final evaluation: none (in check)";
@@ -1107,44 +1139,59 @@ std::string Eval::trace(const Position& pos) {
 
   std::memset(scores, 0, sizeof(scores));
 
-  pos.this_thread()->contempt = SCORE_ZERO; // Reset any dynamic contempt
+  // Reset any global variable used in eval
+  pos.this_thread()->trend           = SCORE_ZERO;
+  pos.this_thread()->bestValue       = VALUE_ZERO;
+  pos.this_thread()->optimism[WHITE] = VALUE_ZERO;
+  pos.this_thread()->optimism[BLACK] = VALUE_ZERO;
 
   v = Evaluation<TRACE>(pos).value();
 
   ss << std::showpoint << std::noshowpos << std::fixed << std::setprecision(2)
-     << "     Term    |    White    |    Black    |    Total   \n"
+     << " Contributing terms for the classical eval:\n"
-     << "             |   MG    EG  |   MG    EG  |   MG    EG \n"
+     << "+------------+-------------+-------------+-------------+\n"
-     << " ------------+-------------+-------------+------------\n"
+     << "|    Term    |    White    |    Black    |    Total    |\n"
-     << "    Material | " << Term(MATERIAL)
+     << "|            |   MG    EG  |   MG    EG  |   MG    EG  |\n"
-     << "   Imbalance | " << Term(IMBALANCE)
+     << "+------------+-------------+-------------+-------------+\n"
-     << "       Pawns | " << Term(PAWN)
+     << "|   Material | " << Term(MATERIAL)
-     << "     Knights | " << Term(KNIGHT)
+     << "|  Imbalance | " << Term(IMBALANCE)
-     << "     Bishops | " << Term(BISHOP)
+     << "|      Pawns | " << Term(PAWN)
-     << "       Rooks | " << Term(ROOK)
+     << "|    Knights | " << Term(KNIGHT)
-     << "      Queens | " << Term(QUEEN)
+     << "|    Bishops | " << Term(BISHOP)
-     << "    Mobility | " << Term(MOBILITY)
+     << "|      Rooks | " << Term(ROOK)
-     << " King safety | " << Term(KING)
+     << "|     Queens | " << Term(QUEEN)
-     << "     Threats | " << Term(THREAT)
+     << "|   Mobility | " << Term(MOBILITY)
-     << "      Passed | " << Term(PASSED)
+     << "|King safety | " << Term(KING)
-     << "       Space | " << Term(SPACE)
+     << "|    Threats | " << Term(THREAT)
-     << "    Winnable | " << Term(WINNABLE)
+     << "|     Passed | " << Term(PASSED)
-     << " ------------+-------------+-------------+------------\n"
+     << "|      Space | " << Term(SPACE)
-     << "       Total | " << Term(TOTAL);
+     << "|   Winnable | " << Term(WINNABLE)
-
+     << "+------------+-------------+-------------+-------------+\n"
-  v = pos.side_to_move() == WHITE ? v : -v;
+     << "|      Total | " << Term(TOTAL)
-
+     << "+------------+-------------+-------------+-------------+\n";
-  ss << "\nClassical evaluation: " << to_cp(v) << " (white side)\n";
 
+  if (Eval::useNNUE)
+      ss << '\n' << NNUE::trace(pos) << '\n';
+
+  ss << std::showpoint << std::showpos << std::fixed << std::setprecision(2) << std::setw(15);
+
+  v = pos.side_to_move() == WHITE ? v : -v;
+  ss << "\nClassical evaluation   " << to_cp(v) << " (white side)\n";
   if (Eval::useNNUE)
   {
-      v = NNUE::evaluate(pos);
+      v = NNUE::evaluate(pos, false);
       v = pos.side_to_move() == WHITE ? v : -v;
-      ss << "\nNNUE evaluation:      " << to_cp(v) << " (white side)\n";
+      ss << "NNUE evaluation        " << to_cp(v) << " (white side)\n";
   }
 
   v = evaluate(pos);
   v = pos.side_to_move() == WHITE ? v : -v;
-  ss << "\nFinal evaluation:     " << to_cp(v) << " (white side)\n";
+  ss << "Final evaluation       " << to_cp(v) << " (white side)";
+  if (Eval::useNNUE)
+     ss << " [with scaled NNUE, hybrid, ...]";
+  ss << "\n";
 
   return ss.str();
 }
+
+} // namespace Stockfish

src/evaluate.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -20,33 +20,43 @@
 #define EVALUATE_H_INCLUDED
 
 #include <string>
+#include <optional>
 
 #include "types.h"
 
+namespace Stockfish {
+
 class Position;
 
 namespace Eval {
 
-  std::string trace(const Position& pos);
+  std::string trace(Position& pos);
   Value evaluate(const Position& pos);
 
   extern bool useNNUE;
-  extern std::string eval_file_loaded;
+  extern std::string currentEvalFileName;
 
   // The default net name MUST follow the format nn-[SHA256 first 12 digits].nnue
   // for the build process (profile-build and fishtest) to work. Do not change the
   // name of the macro, as it is used in the Makefile.
-  #define EvalFileDefaultName   "nn-62ef826d1a6d.nnue"
+  #define EvalFileDefaultName   "nn-6877cd24400e.nnue"
 
   namespace NNUE {
 
-    Value evaluate(const Position& pos);
+    std::string trace(Position& pos);
-    bool load_eval(std::string name, std::istream& stream);
+    Value evaluate(const Position& pos, bool adjusted = false);
+
     void init();
     void verify();
 
+    bool load_eval(std::string name, std::istream& stream);
+    bool save_eval(std::ostream& stream);
+    bool save_eval(const std::optional<std::string>& filename);
+
   } // namespace NNUE
 
 } // namespace Eval
 
+} // namespace Stockfish
+
 #endif // #ifndef EVALUATE_H_INCLUDED

src/main.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -28,6 +28,8 @@
 #include "tt.h"
 #include "uci.h"
 
+using namespace Stockfish;
+
 int main(int argc, char* argv[]) {
 
   std::cout << engine_info() << std::endl;

src/material.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -24,6 +24,8 @@
 
 using namespace std;
 
+namespace Stockfish {
+
 namespace {
   #define S(mg, eg) make_score(mg, eg)
 
@@ -72,7 +74,7 @@ namespace {
 
   bool is_KBPsK(const Position& pos, Color us) {
     return   pos.non_pawn_material(us) == BishopValueMg
-          && pos.count<PAWN  >(us) >= 1;
+          && pos.count<PAWN>(us) >= 1;
   }
 
   bool is_KQKRPs(const Position& pos, Color us) {
@@ -223,3 +225,5 @@ Entry* probe(const Position& pos) {
 }
 
 } // namespace Material
+
+} // namespace Stockfish

src/material.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -24,7 +24,7 @@
 #include "position.h"
 #include "types.h"
 
-namespace Material {
+namespace Stockfish::Material {
 
 /// Material::Entry contains various information about a material configuration.
 /// It contains a material imbalance evaluation, a function pointer to a special
@@ -66,6 +66,6 @@ typedef HashTable<Entry, 8192> Table;
 
 Entry* probe(const Position& pos);
 
-} // namespace Material
+} // namespace Stockfish::Material
 
 #endif // #ifndef MATERIAL_H_INCLUDED

src/misc.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -36,6 +36,8 @@ typedef bool(*fun1_t)(LOGICAL_PROCESSOR_RELATIONSHIP,
                       PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX, PDWORD);
 typedef bool(*fun2_t)(USHORT, PGROUP_AFFINITY);
 typedef bool(*fun3_t)(HANDLE, CONST GROUP_AFFINITY*, PGROUP_AFFINITY);
+typedef bool(*fun4_t)(USHORT, PGROUP_AFFINITY, USHORT, PUSHORT);
+typedef WORD(*fun5_t)();
 }
 #endif
 
@@ -51,7 +53,7 @@ typedef bool(*fun3_t)(HANDLE, CONST GROUP_AFFINITY*, PGROUP_AFFINITY);
 #include <sys/mman.h>
 #endif
 
-#if defined(__APPLE__) || defined(__ANDROID__) || defined(__OpenBSD__) || (defined(__GLIBCXX__) && !defined(_GLIBCXX_HAVE_ALIGNED_ALLOC) && !defined(_WIN32))
+#if defined(__APPLE__) || defined(__ANDROID__) || defined(__OpenBSD__) || (defined(__GLIBCXX__) && !defined(_GLIBCXX_HAVE_ALIGNED_ALLOC) && !defined(_WIN32)) || defined(__e2k__)
 #define POSIXALIGNEDALLOC
 #include <stdlib.h>
 #endif
@@ -61,6 +63,8 @@ typedef bool(*fun3_t)(HANDLE, CONST GROUP_AFFINITY*, PGROUP_AFFINITY);
 
 using namespace std;
 
+namespace Stockfish {
+
 namespace {
 
 /// Version number. If Version is left empty, then compile date in the format
@@ -108,7 +112,14 @@ public:
 
     static Logger l;
 
-    if (!fname.empty() && !l.file.is_open())
+    if (l.file.is_open())
+    {
+        cout.rdbuf(l.out.buf);
+        cin.rdbuf(l.in.buf);
+        l.file.close();
+    }
+
+    if (!fname.empty())
     {
         l.file.open(fname, ifstream::out);
 
@@ -121,12 +132,6 @@ public:
         cin.rdbuf(&l.in);
         cout.rdbuf(&l.out);
     }
-    else if (fname.empty() && l.file.is_open())
-    {
-        cout.rdbuf(l.out.buf);
-        cin.rdbuf(l.in.buf);
-        l.file.close();
-    }
   }
 };
 
@@ -138,7 +143,7 @@ public:
 /// the program was compiled) or "Stockfish <Version>", depending on whether
 /// Version is empty.
 
-const string engine_info(bool to_uci) {
+string engine_info(bool to_uci) {
 
   const string months("Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec");
   string month, day, year;
@@ -161,7 +166,7 @@ const string engine_info(bool to_uci) {
 
 /// compiler_info() returns a string trying to describe the compiler we use
 
-const std::string compiler_info() {
+std::string compiler_info() {
 
   #define stringify2(x) #x
   #define stringify(x) stringify2(x)
@@ -190,6 +195,18 @@ const std::string compiler_info() {
      compiler += "(version ";
      compiler += stringify(_MSC_FULL_VER) "." stringify(_MSC_BUILD);
      compiler += ")";
+  #elif defined(__e2k__) && defined(__LCC__)
+    #define dot_ver2(n) \
+      compiler += (char)'.'; \
+      compiler += (char)('0' + (n) / 10); \
+      compiler += (char)('0' + (n) % 10);
+
+     compiler += "MCST LCC ";
+     compiler += "(version ";
+     compiler += std::to_string(__LCC__ / 100);
+     dot_ver2(__LCC__ % 100)
+     dot_ver2(__LCC_MINOR__)
+     compiler += ")";
   #elif __GNUC__
      compiler += "g++ (GNUC) ";
      compiler += make_version_string(__GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__);
@@ -361,7 +378,12 @@ void std_aligned_free(void* ptr) {
 
 #if defined(_WIN32)
 
-static void* aligned_large_pages_alloc_win(size_t allocSize) {
+static void* aligned_large_pages_alloc_windows(size_t allocSize) {
+
+  #if !defined(_WIN64)
+    (void)allocSize; // suppress unused-parameter compiler warning
+    return nullptr;
+  #else
 
   HANDLE hProcessToken { };
   LUID luid { };
@@ -404,12 +426,14 @@ static void* aligned_large_pages_alloc_win(size_t allocSize) {
   CloseHandle(hProcessToken);
 
   return mem;
+
+  #endif
 }
 
 void* aligned_large_pages_alloc(size_t allocSize) {
 
   // Try to allocate large pages
-  void* mem = aligned_large_pages_alloc_win(allocSize);
+  void* mem = aligned_large_pages_alloc_windows(allocSize);
 
   // Fall back to regular, page aligned, allocation if necessary
   if (!mem)
@@ -449,8 +473,9 @@ void aligned_large_pages_free(void* mem) {
   if (mem && !VirtualFree(mem, 0, MEM_RELEASE))
   {
       DWORD err = GetLastError();
-      std::cerr << "Failed to free transposition table. Error code: 0x" <<
+      std::cerr << "Failed to free large page memory. Error code: 0x"
-          std::hex << err << std::dec << std::endl;
+                << std::hex << err
+                << std::dec << std::endl;
       exit(EXIT_FAILURE);
   }
 }
@@ -472,11 +497,11 @@ void bindThisThread(size_t) {}
 
 #else
 
-/// best_group() retrieves logical processor information using Windows specific
+/// best_node() retrieves logical processor information using Windows specific
-/// API and returns the best group id for the thread with index idx. Original
+/// API and returns the best node id for the thread with index idx. Original
 /// code from Texel by Peter Österlund.
 
-int best_group(size_t idx) {
+int best_node(size_t idx) {
 
   int threads = 0;
   int nodes = 0;
@@ -490,7 +515,8 @@ int best_group(size_t idx) {
   if (!fun1)
       return -1;
 
-  // First call to get returnLength. We expect it to fail due to null buffer
+  // First call to GetLogicalProcessorInformationEx() to get returnLength.
+  // We expect the call to fail due to null buffer.
   if (fun1(RelationAll, nullptr, &returnLength))
       return -1;
 
@@ -498,7 +524,7 @@ int best_group(size_t idx) {
   SYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX *buffer, *ptr;
   ptr = buffer = (SYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX*)malloc(returnLength);
 
-  // Second call, now we expect to succeed
+  // Second call to GetLogicalProcessorInformationEx(), now we expect to succeed
   if (!fun1(RelationAll, buffer, &returnLength))
   {
       free(buffer);
@@ -548,22 +574,38 @@ int best_group(size_t idx) {
 void bindThisThread(size_t idx) {
 
   // Use only local variables to be thread-safe
-  int group = best_group(idx);
+  int node = best_node(idx);
 
-  if (group == -1)
+  if (node == -1)
       return;
 
   // Early exit if the needed API are not available at runtime
   HMODULE k32 = GetModuleHandle("Kernel32.dll");
   auto fun2 = (fun2_t)(void(*)())GetProcAddress(k32, "GetNumaNodeProcessorMaskEx");
   auto fun3 = (fun3_t)(void(*)())GetProcAddress(k32, "SetThreadGroupAffinity");
+  auto fun4 = (fun4_t)(void(*)())GetProcAddress(k32, "GetNumaNodeProcessorMask2");
+  auto fun5 = (fun5_t)(void(*)())GetProcAddress(k32, "GetMaximumProcessorGroupCount");
 
   if (!fun2 || !fun3)
       return;
 
-  GROUP_AFFINITY affinity;
+  if (!fun4 || !fun5)
-  if (fun2(group, &affinity))
+  {
-      fun3(GetCurrentThread(), &affinity, nullptr);
+      GROUP_AFFINITY affinity;
+      if (fun2(node, &affinity))                                                 // GetNumaNodeProcessorMaskEx
+          fun3(GetCurrentThread(), &affinity, nullptr);                          // SetThreadGroupAffinity
+  }
+  else
+  {
+      // If a numa node has more than one processor group, we assume they are
+      // sized equal and we spread threads evenly across the groups.
+      USHORT elements, returnedElements;
+      elements = fun5();                                                         // GetMaximumProcessorGroupCount
+      GROUP_AFFINITY *affinity = (GROUP_AFFINITY*)malloc(elements * sizeof(GROUP_AFFINITY));
+      if (fun4(node, affinity, elements, &returnedElements))                     // GetNumaNodeProcessorMask2
+          fun3(GetCurrentThread(), &affinity[idx % returnedElements], nullptr);  // SetThreadGroupAffinity
+      free(affinity);
+  }
 }
 
 #endif
@@ -626,3 +668,5 @@ void init(int argc, char* argv[]) {
 
 
 } // namespace CommandLine
+
+} // namespace Stockfish

src/misc.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -28,8 +28,10 @@
 
 #include "types.h"
 
-const std::string engine_info(bool to_uci = false);
+namespace Stockfish {
-const std::string compiler_info();
+
+std::string engine_info(bool to_uci = false);
+std::string compiler_info();
 void prefetch(void* addr);
 void start_logger(const std::string& fname);
 void* std_aligned_alloc(size_t alignment, size_t size);
@@ -64,9 +66,10 @@ std::ostream& operator<<(std::ostream&, SyncCout);
 #define sync_cout std::cout << IO_LOCK
 #define sync_endl std::endl << IO_UNLOCK
 
-// `ptr` must point to an array of size at least
+
-// `sizeof(T) * N + alignment` bytes, where `N` is the
+// align_ptr_up() : get the first aligned element of an array.
-// number of elements in the array.
+// ptr must point to an array of size at least `sizeof(T) * N + alignment` bytes,
+// where N is the number of elements in the array.
 template <uintptr_t Alignment, typename T>
 T* align_ptr_up(T* ptr)
 {
@@ -76,6 +79,95 @@ T* align_ptr_up(T* ptr)
   return reinterpret_cast<T*>(reinterpret_cast<char*>((ptrint + (Alignment - 1)) / Alignment * Alignment));
 }
 
+
+// IsLittleEndian : true if and only if the binary is compiled on a little endian machine
+static inline const union { uint32_t i; char c[4]; } Le = { 0x01020304 };
+static inline const bool IsLittleEndian = (Le.c[0] == 4);
+
+
+// RunningAverage : a class to calculate a running average of a series of values.
+// For efficiency, all computations are done with integers.
+class RunningAverage {
+  public:
+
+      // Constructor
+      RunningAverage() {}
+
+      // Reset the running average to rational value p / q
+      void set(int64_t p, int64_t q)
+        { average = p * PERIOD * RESOLUTION / q; }
+
+      // Update average with value v
+      void update(int64_t v)
+        { average = RESOLUTION * v + (PERIOD - 1) * average / PERIOD; }
+
+      // Test if average is strictly greater than rational a / b
+      bool is_greater(int64_t a, int64_t b)
+        { return b * average > a * PERIOD * RESOLUTION ; }
+
+      int64_t value()
+        { return average / (PERIOD * RESOLUTION); }
+
+  private :
+      static constexpr int64_t PERIOD     = 4096;
+      static constexpr int64_t RESOLUTION = 1024;
+      int64_t average;
+};
+
+template <typename T, std::size_t MaxSize>
+class ValueList {
+
+public:
+  std::size_t size() const { return size_; }
+  void resize(std::size_t newSize) { size_ = newSize; }
+  void push_back(const T& value) { values_[size_++] = value; }
+  T& operator[](std::size_t index) { return values_[index]; }
+  T* begin() { return values_; }
+  T* end() { return values_ + size_; }
+  const T& operator[](std::size_t index) const { return values_[index]; }
+  const T* begin() const { return values_; }
+  const T* end() const { return values_ + size_; }
+
+  void swap(ValueList& other) {
+    const std::size_t maxSize = std::max(size_, other.size_);
+    for (std::size_t i = 0; i < maxSize; ++i) {
+      std::swap(values_[i], other.values_[i]);
+    }
+    std::swap(size_, other.size_);
+  }
+
+private:
+  T values_[MaxSize];
+  std::size_t size_ = 0;
+};
+
+
+/// sigmoid(t, x0, y0, C, P, Q) implements a sigmoid-like function using only integers,
+/// with the following properties:
+///
+///  -  sigmoid is centered in (x0, y0)
+///  -  sigmoid has amplitude [-P/Q , P/Q] instead of [-1 , +1]
+///  -  limit is (y0 - P/Q) when t tends to -infinity
+///  -  limit is (y0 + P/Q) when t tends to +infinity
+///  -  the slope can be adjusted using C > 0, smaller C giving a steeper sigmoid
+///  -  the slope of the sigmoid when t = x0 is P/(Q*C)
+///  -  sigmoid is increasing with t when P > 0 and Q > 0
+///  -  to get a decreasing sigmoid, call with -t, or change sign of P
+///  -  mean value of the sigmoid is y0
+///
+/// Use <https://www.desmos.com/calculator/jhh83sqq92> to draw the sigmoid
+
+inline int64_t sigmoid(int64_t t, int64_t x0,
+                                  int64_t y0,
+                                  int64_t  C,
+                                  int64_t  P,
+                                  int64_t  Q)
+{
+   assert(C > 0);
+   return y0 + P * (t-x0) / (Q * (std::abs(t-x0) + C)) ;
+}
+
+
 /// xorshift64star Pseudo-Random Number Generator
 /// This class is based on original code written and dedicated
 /// to the public domain by Sebastiano Vigna (2014).
@@ -143,4 +235,6 @@ namespace CommandLine {
   extern std::string workingDirectory; // path of the working directory
 }
 
+} // namespace Stockfish
+
 #endif // #ifndef MISC_H_INCLUDED

src/movegen.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,24 +21,21 @@
 #include "movegen.h"
 #include "position.h"
 
+namespace Stockfish {
+
 namespace {
 
   template<GenType Type, Direction D>
-  ExtMove* make_promotions(ExtMove* moveList, Square to, Square ksq) {
+  ExtMove* make_promotions(ExtMove* moveList, Square to) {
 
     if (Type == CAPTURES || Type == EVASIONS || Type == NON_EVASIONS)
-    {
         *moveList++ = make<PROMOTION>(to - D, to, QUEEN);
-        if (attacks_bb<KNIGHT>(to) & ksq)
-            *moveList++ = make<PROMOTION>(to - D, to, KNIGHT);
-    }
 
     if (Type == QUIETS || Type == EVASIONS || Type == NON_EVASIONS)
     {
         *moveList++ = make<PROMOTION>(to - D, to, ROOK);
         *moveList++ = make<PROMOTION>(to - D, to, BISHOP);
-        if (!(attacks_bb<KNIGHT>(to) & ksq))
+        *moveList++ = make<PROMOTION>(to - D, to, KNIGHT);
-            *moveList++ = make<PROMOTION>(to - D, to, KNIGHT);
     }
 
     return moveList;
@@ -55,20 +52,16 @@ namespace {
     constexpr Direction UpRight  = (Us == WHITE ? NORTH_EAST : SOUTH_WEST);
     constexpr Direction UpLeft   = (Us == WHITE ? NORTH_WEST : SOUTH_EAST);
 
-    const Square ksq = pos.square<KING>(Them);
+    const Bitboard emptySquares = ~pos.pieces();
-    Bitboard emptySquares;
+    const Bitboard enemies      =  Type == EVASIONS ? pos.checkers()
+                                                    : pos.pieces(Them);
 
     Bitboard pawnsOn7    = pos.pieces(Us, PAWN) &  TRank7BB;
     Bitboard pawnsNotOn7 = pos.pieces(Us, PAWN) & ~TRank7BB;
 
-    Bitboard enemies = (Type == EVASIONS ? pos.pieces(Them) & target:
-                        Type == CAPTURES ? target : pos.pieces(Them));
-
     // Single and double pawn pushes, no promotions
     if (Type != CAPTURES)
     {
-        emptySquares = (Type == QUIETS || Type == QUIET_CHECKS ? target : ~pos.pieces());
-
         Bitboard b1 = shift<Up>(pawnsNotOn7)   & emptySquares;
         Bitboard b2 = shift<Up>(b1 & TRank3BB) & emptySquares;
 
@@ -80,33 +73,24 @@ namespace {
 
         if (Type == QUIET_CHECKS)
         {
-            b1 &= pawn_attacks_bb(Them, ksq);
+            // To make a quiet check, you either make a direct check by pushing a pawn
-            b2 &= pawn_attacks_bb(Them, ksq);
+            // or push a blocker pawn that is not on the same file as the enemy king.
-
+            // Discovered check promotion has been already generated amongst the captures.
-            // Add pawn pushes which give discovered check. This is possible only
+            Square ksq = pos.square<KING>(Them);
-            // if the pawn is not on the same file as the enemy king, because we
+            Bitboard dcCandidatePawns = pos.blockers_for_king(Them) & ~file_bb(ksq);
-            // don't generate captures. Note that a possible discovered check
+            b1 &= pawn_attacks_bb(Them, ksq) | shift<   Up>(dcCandidatePawns);
-            // promotion has been already generated amongst the captures.
+            b2 &= pawn_attacks_bb(Them, ksq) | shift<Up+Up>(dcCandidatePawns);
-            Bitboard dcCandidateQuiets = pos.blockers_for_king(Them) & pawnsNotOn7;
-            if (dcCandidateQuiets)
-            {
-                Bitboard dc1 = shift<Up>(dcCandidateQuiets) & emptySquares & ~file_bb(ksq);
-                Bitboard dc2 = shift<Up>(dc1 & TRank3BB) & emptySquares;
-
-                b1 |= dc1;
-                b2 |= dc2;
-            }
         }
 
         while (b1)
         {
-            Square to = pop_lsb(&b1);
+            Square to = pop_lsb(b1);
             *moveList++ = make_move(to - Up, to);
         }
 
         while (b2)
         {
-            Square to = pop_lsb(&b2);
+            Square to = pop_lsb(b2);
             *moveList++ = make_move(to - Up - Up, to);
         }
     }
@@ -114,24 +98,21 @@ namespace {
     // Promotions and underpromotions
     if (pawnsOn7)
     {
-        if (Type == CAPTURES)
-            emptySquares = ~pos.pieces();
-
-        if (Type == EVASIONS)
-            emptySquares &= target;
-
         Bitboard b1 = shift<UpRight>(pawnsOn7) & enemies;
         Bitboard b2 = shift<UpLeft >(pawnsOn7) & enemies;
         Bitboard b3 = shift<Up     >(pawnsOn7) & emptySquares;
 
+        if (Type == EVASIONS)
+            b3 &= target;
+
         while (b1)
-            moveList = make_promotions<Type, UpRight>(moveList, pop_lsb(&b1), ksq);
+            moveList = make_promotions<Type, UpRight>(moveList, pop_lsb(b1));
 
         while (b2)
-            moveList = make_promotions<Type, UpLeft >(moveList, pop_lsb(&b2), ksq);
+            moveList = make_promotions<Type, UpLeft >(moveList, pop_lsb(b2));
 
         while (b3)
-            moveList = make_promotions<Type, Up     >(moveList, pop_lsb(&b3), ksq);
+            moveList = make_promotions<Type, Up     >(moveList, pop_lsb(b3));
     }
 
     // Standard and en passant captures
@@ -142,13 +123,13 @@ namespace {
 
         while (b1)
         {
-            Square to = pop_lsb(&b1);
+            Square to = pop_lsb(b1);
             *moveList++ = make_move(to - UpRight, to);
         }
 
         while (b2)
         {
-            Square to = pop_lsb(&b2);
+            Square to = pop_lsb(b2);
             *moveList++ = make_move(to - UpLeft, to);
         }
 
@@ -156,7 +137,7 @@ namespace {
         {
             assert(rank_of(pos.ep_square()) == relative_rank(Us, RANK_6));
 
-            // An en passant capture cannot resolve a discovered check.
+            // An en passant capture cannot resolve a discovered check
             if (Type == EVASIONS && (target & (pos.ep_square() + Up)))
                 return moveList;
 
@@ -165,7 +146,7 @@ namespace {
             assert(b1);
 
             while (b1)
-                *moveList++ = make<EN_PASSANT>(pop_lsb(&b1), pos.ep_square());
+                *moveList++ = make<EN_PASSANT>(pop_lsb(b1), pos.ep_square());
         }
     }
 
@@ -173,27 +154,24 @@ namespace {
   }
 
 
-  template<PieceType Pt, bool Checks>
+  template<Color Us, PieceType Pt, bool Checks>
-  ExtMove* generate_moves(const Position& pos, ExtMove* moveList, Bitboard piecesToMove, Bitboard target) {
+  ExtMove* generate_moves(const Position& pos, ExtMove* moveList, Bitboard target) {
 
     static_assert(Pt != KING && Pt != PAWN, "Unsupported piece type in generate_moves()");
 
-    Bitboard bb = piecesToMove & pos.pieces(Pt);
+    Bitboard bb = pos.pieces(Us, Pt);
-
-    if (!bb)
-        return moveList;
-
-    [[maybe_unused]] const Bitboard checkSquares = pos.check_squares(Pt);
-
-    while (bb) {
-        Square from = pop_lsb(&bb);
 
+    while (bb)
+    {
+        Square from = pop_lsb(bb);
         Bitboard b = attacks_bb<Pt>(from, pos.pieces()) & target;
-        if constexpr (Checks)
+
-            b &= checkSquares;
+        // To check, you either move freely a blocker or make a direct check.
+        if (Checks && (Pt == QUEEN || !(pos.blockers_for_king(~Us) & from)))
+            b &= pos.check_squares(Pt);
 
         while (b)
-            *moveList++ = make_move(from, pop_lsb(&b));
+            *moveList++ = make_move(from, pop_lsb(b));
     }
 
     return moveList;
@@ -206,45 +184,34 @@ namespace {
     static_assert(Type != LEGAL, "Unsupported type in generate_all()");
 
     constexpr bool Checks = Type == QUIET_CHECKS; // Reduce template instantiations
-    Bitboard target, piecesToMove = pos.pieces(Us);
+    const Square ksq = pos.square<KING>(Us);
+    Bitboard target;
 
-    if(Type == QUIET_CHECKS)
+    // Skip generating non-king moves when in double check
-        piecesToMove &= ~pos.blockers_for_king(~Us);
+    if (Type != EVASIONS || !more_than_one(pos.checkers()))
-
-    switch (Type)
     {
-        case CAPTURES:
+        target = Type == EVASIONS     ?  between_bb(ksq, lsb(pos.checkers()))
-            target =  pos.pieces(~Us);
+               : Type == NON_EVASIONS ? ~pos.pieces( Us)
-            break;
+               : Type == CAPTURES     ?  pos.pieces(~Us)
-        case QUIETS:
+                                      : ~pos.pieces(   ); // QUIETS || QUIET_CHECKS
-        case QUIET_CHECKS:
+
-            target = ~pos.pieces();
+        moveList = generate_pawn_moves<Us, Type>(pos, moveList, target);
-            break;
+        moveList = generate_moves<Us, KNIGHT, Checks>(pos, moveList, target);
-        case EVASIONS:
+        moveList = generate_moves<Us, BISHOP, Checks>(pos, moveList, target);
-        {
+        moveList = generate_moves<Us,   ROOK, Checks>(pos, moveList, target);
-            Square checksq = lsb(pos.checkers());
+        moveList = generate_moves<Us,  QUEEN, Checks>(pos, moveList, target);
-            target = between_bb(pos.square<KING>(Us), checksq) | checksq;
-            break;
-        }
-        case NON_EVASIONS:
-            target = ~pos.pieces(Us);
-            break;
     }
 
-    moveList = generate_pawn_moves<Us, Type>(pos, moveList, target);
+    if (!Checks || pos.blockers_for_king(~Us) & ksq)
-    moveList = generate_moves<KNIGHT, Checks>(pos, moveList, piecesToMove, target);
-    moveList = generate_moves<BISHOP, Checks>(pos, moveList, piecesToMove, target);
-    moveList = generate_moves<  ROOK, Checks>(pos, moveList, piecesToMove, target);
-    moveList = generate_moves< QUEEN, Checks>(pos, moveList, piecesToMove, target);
-
-    if (Type != QUIET_CHECKS && Type != EVASIONS)
     {
-        Square ksq = pos.square<KING>(Us);
+        Bitboard b = attacks_bb<KING>(ksq) & (Type == EVASIONS ? ~pos.pieces(Us) : target);
-        Bitboard b = attacks_bb<KING>(ksq) & target;
+        if (Checks)
-        while (b)
+            b &= ~attacks_bb<QUEEN>(pos.square<KING>(~Us));
-            *moveList++ = make_move(ksq, pop_lsb(&b));
 
-        if ((Type != CAPTURES) && pos.can_castle(Us & ANY_CASTLING))
+        while (b)
+            *moveList++ = make_move(ksq, pop_lsb(b));
+
+        if ((Type == QUIETS || Type == NON_EVASIONS) && pos.can_castle(Us & ANY_CASTLING))
             for (CastlingRights cr : { Us & KING_SIDE, Us & QUEEN_SIDE } )
                 if (!pos.castling_impeded(cr) && pos.can_castle(cr))
                     *moveList++ = make<CASTLING>(ksq, pos.castling_rook_square(cr));
@@ -256,8 +223,10 @@ namespace {
 } // namespace
 
 
-/// <CAPTURES>     Generates all pseudo-legal captures plus queen and checking knight promotions
+/// <CAPTURES>     Generates all pseudo-legal captures plus queen promotions
-/// <QUIETS>       Generates all pseudo-legal non-captures and underpromotions (except checking knight)
+/// <QUIETS>       Generates all pseudo-legal non-captures and underpromotions
+/// <EVASIONS>     Generates all pseudo-legal check evasions when the side to move is in check
+/// <QUIET_CHECKS> Generates all pseudo-legal non-captures giving check, except castling and promotions
 /// <NON_EVASIONS> Generates all pseudo-legal captures and non-captures
 ///
 /// Returns a pointer to the end of the move list.
@@ -265,8 +234,8 @@ namespace {
 template<GenType Type>
 ExtMove* generate(const Position& pos, ExtMove* moveList) {
 
-  static_assert(Type == CAPTURES || Type == QUIETS || Type == NON_EVASIONS, "Unsupported type in generate()");
+  static_assert(Type != LEGAL, "Unsupported type in generate()");
-  assert(!pos.checkers());
+  assert((Type == EVASIONS) == (bool)pos.checkers());
 
   Color us = pos.side_to_move();
 
@@ -277,70 +246,11 @@ ExtMove* generate(const Position& pos, ExtMove* moveList) {
 // Explicit template instantiations
 template ExtMove* generate<CAPTURES>(const Position&, ExtMove*);
 template ExtMove* generate<QUIETS>(const Position&, ExtMove*);
+template ExtMove* generate<EVASIONS>(const Position&, ExtMove*);
+template ExtMove* generate<QUIET_CHECKS>(const Position&, ExtMove*);
 template ExtMove* generate<NON_EVASIONS>(const Position&, ExtMove*);
 
 
-/// generate<QUIET_CHECKS> generates all pseudo-legal non-captures giving check,
-/// except castling. Returns a pointer to the end of the move list.
-template<>
-ExtMove* generate<QUIET_CHECKS>(const Position& pos, ExtMove* moveList) {
-
-  assert(!pos.checkers());
-
-  Color us = pos.side_to_move();
-  Bitboard dc = pos.blockers_for_king(~us) & pos.pieces(us) & ~pos.pieces(PAWN);
-
-  while (dc)
-  {
-     Square from = pop_lsb(&dc);
-     PieceType pt = type_of(pos.piece_on(from));
-
-     Bitboard b = attacks_bb(pt, from, pos.pieces()) & ~pos.pieces();
-
-     if (pt == KING)
-         b &= ~attacks_bb<QUEEN>(pos.square<KING>(~us));
-
-     while (b)
-         *moveList++ = make_move(from, pop_lsb(&b));
-  }
-
-  return us == WHITE ? generate_all<WHITE, QUIET_CHECKS>(pos, moveList)
-                     : generate_all<BLACK, QUIET_CHECKS>(pos, moveList);
-}
-
-
-/// generate<EVASIONS> generates all pseudo-legal check evasions when the side
-/// to move is in check. Returns a pointer to the end of the move list.
-template<>
-ExtMove* generate<EVASIONS>(const Position& pos, ExtMove* moveList) {
-
-  assert(pos.checkers());
-
-  Color us = pos.side_to_move();
-  Square ksq = pos.square<KING>(us);
-  Bitboard sliderAttacks = 0;
-  Bitboard sliders = pos.checkers() & ~pos.pieces(KNIGHT, PAWN);
-
-  // Find all the squares attacked by slider checkers. We will remove them from
-  // the king evasions in order to skip known illegal moves, which avoids any
-  // useless legality checks later on.
-  while (sliders)
-      sliderAttacks |= line_bb(ksq, pop_lsb(&sliders)) & ~pos.checkers();
-
-  // Generate evasions for king, capture and non capture moves
-  Bitboard b = attacks_bb<KING>(ksq) & ~pos.pieces(us) & ~sliderAttacks;
-  while (b)
-      *moveList++ = make_move(ksq, pop_lsb(&b));
-
-  if (more_than_one(pos.checkers()))
-      return moveList; // Double check, only a king move can save the day
-
-  // Generate blocking evasions or captures of the checking piece
-  return us == WHITE ? generate_all<WHITE, EVASIONS>(pos, moveList)
-                     : generate_all<BLACK, EVASIONS>(pos, moveList);
-}
-
-
 /// generate<LEGAL> generates all the legal moves in the given position
 
 template<>
@@ -362,3 +272,5 @@ ExtMove* generate<LEGAL>(const Position& pos, ExtMove* moveList) {
 
   return moveList;
 }
+
+} // namespace Stockfish

src/movegen.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -23,6 +23,8 @@
 
 #include "types.h"
 
+namespace Stockfish {
+
 class Position;
 
 enum GenType {
@@ -70,4 +72,6 @@ private:
   ExtMove moveList[MAX_MOVES], *last;
 };
 
+} // namespace Stockfish
+
 #endif // #ifndef MOVEGEN_H_INCLUDED

src/movepick.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -20,6 +20,8 @@
 
 #include "movepick.h"
 
+namespace Stockfish {
+
 namespace {
 
   enum Stages {
@@ -54,11 +56,14 @@ namespace {
 /// ordering is at the current node.
 
 /// MovePicker constructor for the main search
-MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const ButterflyHistory* mh, const LowPlyHistory* lp,
+MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const ButterflyHistory* mh,
-                       const CapturePieceToHistory* cph, const PieceToHistory** ch, Move cm, const Move* killers, int pl)
+                                                             const CapturePieceToHistory* cph,
-           : pos(p), mainHistory(mh), lowPlyHistory(lp), captureHistory(cph), continuationHistory(ch),
+                                                             const PieceToHistory** ch,
-             ttMove(ttm), refutations{{killers[0], 0}, {killers[1], 0}, {cm, 0}}, depth(d), ply(pl) {
+                                                             Move cm,
-
+                                                             const Move* killers)
+           : pos(p), mainHistory(mh), captureHistory(cph), continuationHistory(ch),
+             ttMove(ttm), refutations{{killers[0], 0}, {killers[1], 0}, {cm, 0}}, depth(d)
+{
   assert(d > 0);
 
   stage = (pos.checkers() ? EVASION_TT : MAIN_TT) +
@@ -67,9 +72,11 @@ MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const ButterflyHist
 
 /// MovePicker constructor for quiescence search
 MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const ButterflyHistory* mh,
-                       const CapturePieceToHistory* cph, const PieceToHistory** ch, Square rs)
+                                                             const CapturePieceToHistory* cph,
-           : pos(p), mainHistory(mh), captureHistory(cph), continuationHistory(ch), ttMove(ttm), recaptureSquare(rs), depth(d) {
+                                                             const PieceToHistory** ch,
-
+                                                             Square rs)
+           : pos(p), mainHistory(mh), captureHistory(cph), continuationHistory(ch), ttMove(ttm), recaptureSquare(rs), depth(d)
+{
   assert(d <= 0);
 
   stage = (pos.checkers() ? EVASION_TT : QSEARCH_TT) +
@@ -81,8 +88,8 @@ MovePicker::MovePicker(const Position& p, Move ttm, Depth d, const ButterflyHist
 /// MovePicker constructor for ProbCut: we generate captures with SEE greater
 /// than or equal to the given threshold.
 MovePicker::MovePicker(const Position& p, Move ttm, Value th, const CapturePieceToHistory* cph)
-           : pos(p), captureHistory(cph), ttMove(ttm), threshold(th) {
+           : pos(p), captureHistory(cph), ttMove(ttm), threshold(th)
-
+{
   assert(!pos.checkers());
 
   stage = PROBCUT_TT + !(ttm && pos.capture(ttm)
@@ -108,8 +115,7 @@ void MovePicker::score() {
                    + 2 * (*continuationHistory[0])[pos.moved_piece(m)][to_sq(m)]
                    +     (*continuationHistory[1])[pos.moved_piece(m)][to_sq(m)]
                    +     (*continuationHistory[3])[pos.moved_piece(m)][to_sq(m)]
-                   +     (*continuationHistory[5])[pos.moved_piece(m)][to_sq(m)]
+                   +     (*continuationHistory[5])[pos.moved_piece(m)][to_sq(m)];
-                   + (ply < MAX_LPH ? std::min(4, depth / 3) * (*lowPlyHistory)[ply][from_to(m)] : 0);
 
       else // Type == EVASIONS
       {
@@ -263,3 +269,5 @@ top:
   assert(false);
   return MOVE_NONE; // Silence warning
 }
+
+} // namespace Stockfish

src/movepick.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -27,6 +27,8 @@
 #include "position.h"
 #include "types.h"
 
+namespace Stockfish {
+
 /// StatsEntry stores the stat table value. It is usually a number but could
 /// be a move or even a nested history. We use a class instead of naked value
 /// to directly call history update operator<<() on the entry so to use stats
@@ -84,13 +86,7 @@ enum StatsType { NoCaptures, Captures };
 /// unsuccessful during the current search, and is used for reduction and move
 /// ordering decisions. It uses 2 tables (one for each color) indexed by
 /// the move's from and to squares, see www.chessprogramming.org/Butterfly_Boards
-typedef Stats<int16_t, 13365, COLOR_NB, int(SQUARE_NB) * int(SQUARE_NB)> ButterflyHistory;
+typedef Stats<int16_t, 14365, COLOR_NB, int(SQUARE_NB) * int(SQUARE_NB)> ButterflyHistory;
-
-/// At higher depths LowPlyHistory records successful quiet moves near the root
-/// and quiet moves which are/were in the PV (ttPv). It is cleared with each new
-/// search and filled during iterative deepening.
-constexpr int MAX_LPH = 4;
-typedef Stats<int16_t, 10692, MAX_LPH, int(SQUARE_NB) * int(SQUARE_NB)> LowPlyHistory;
 
 /// CounterMoveHistory stores counter moves indexed by [piece][to] of the previous
 /// move, see www.chessprogramming.org/Countermove_Heuristic
@@ -121,18 +117,16 @@ class MovePicker {
 public:
   MovePicker(const MovePicker&) = delete;
   MovePicker& operator=(const MovePicker&) = delete;
-  MovePicker(const Position&, Move, Value, const CapturePieceToHistory*);
+  MovePicker(const Position&, Move, Depth, const ButterflyHistory*,
+                                           const CapturePieceToHistory*,
+                                           const PieceToHistory**,
+                                           Move,
+                                           const Move*);
   MovePicker(const Position&, Move, Depth, const ButterflyHistory*,
                                            const CapturePieceToHistory*,
                                            const PieceToHistory**,
                                            Square);
-  MovePicker(const Position&, Move, Depth, const ButterflyHistory*,
+  MovePicker(const Position&, Move, Value, const CapturePieceToHistory*);
-                                           const LowPlyHistory*,
-                                           const CapturePieceToHistory*,
-                                           const PieceToHistory**,
-                                           Move,
-                                           const Move*,
-                                           int);
   Move next_move(bool skipQuiets = false);
 
 private:
@@ -143,7 +137,6 @@ private:
 
   const Position& pos;
   const ButterflyHistory* mainHistory;
-  const LowPlyHistory* lowPlyHistory;
   const CapturePieceToHistory* captureHistory;
   const PieceToHistory** continuationHistory;
   Move ttMove;
@@ -152,8 +145,9 @@ private:
   Square recaptureSquare;
   Value threshold;
   Depth depth;
-  int ply;
   ExtMove moves[MAX_MOVES];
 };
 
+} // namespace Stockfish
+
 #endif // #ifndef MOVEPICK_H_INCLUDED

src/nnue/architectures/halfkp_256x2-32-32.h

@@ -1,54 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-// Definition of input features and network structure used in NNUE evaluation function
-
-#ifndef NNUE_HALFKP_256X2_32_32_H_INCLUDED
-#define NNUE_HALFKP_256X2_32_32_H_INCLUDED
-
-#include "../features/feature_set.h"
-#include "../features/half_kp.h"
-
-#include "../layers/input_slice.h"
-#include "../layers/affine_transform.h"
-#include "../layers/clipped_relu.h"
-
-namespace Eval::NNUE {
-
-// Input features used in evaluation function
-using RawFeatures = Features::FeatureSet<
-    Features::HalfKP<Features::Side::kFriend>>;
-
-// Number of input feature dimensions after conversion
-constexpr IndexType kTransformedFeatureDimensions = 256;
-
-namespace Layers {
-
-// Define network structure
-using InputLayer = InputSlice<kTransformedFeatureDimensions * 2>;
-using HiddenLayer1 = ClippedReLU<AffineTransform<InputLayer, 32>>;
-using HiddenLayer2 = ClippedReLU<AffineTransform<HiddenLayer1, 32>>;
-using OutputLayer = AffineTransform<HiddenLayer2, 1>;
-
-}  // namespace Layers
-
-using Network = Layers::OutputLayer;
-
-}  // namespace Eval::NNUE
-
-#endif // #ifndef NNUE_HALFKP_256X2_32_32_H_INCLUDED

src/nnue/evaluate_nnue.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -20,6 +20,9 @@
 
 #include <iostream>
 #include <set>
+#include <sstream>
+#include <iomanip>
+#include <fstream>
 
 #include "../evaluate.h"
 #include "../position.h"
@@ -29,29 +32,30 @@
 
 #include "evaluate_nnue.h"
 
-namespace Eval::NNUE {
+namespace Stockfish::Eval::NNUE {
 
   // Input feature converter
-  LargePagePtr<FeatureTransformer> feature_transformer;
+  LargePagePtr<FeatureTransformer> featureTransformer;
 
   // Evaluation function
-  AlignedPtr<Network> network;
+  AlignedPtr<Network> network[LayerStacks];
 
   // Evaluation function file name
   std::string fileName;
+  std::string netDescription;
 
   namespace Detail {
 
   // Initialize the evaluation function parameters
   template <typename T>
-  void Initialize(AlignedPtr<T>& pointer) {
+  void initialize(AlignedPtr<T>& pointer) {
 
     pointer.reset(reinterpret_cast<T*>(std_aligned_alloc(alignof(T), sizeof(T))));
     std::memset(pointer.get(), 0, sizeof(T));
   }
 
   template <typename T>
-  void Initialize(LargePagePtr<T>& pointer) {
+  void initialize(LargePagePtr<T>& pointer) {
 
     static_assert(alignof(T) <= 4096, "aligned_large_pages_alloc() may fail for such a big alignment requirement of T");
     pointer.reset(reinterpret_cast<T*>(aligned_large_pages_alloc(sizeof(T))));
@@ -60,85 +64,340 @@ namespace Eval::NNUE {
 
   // Read evaluation function parameters
   template <typename T>
-  bool ReadParameters(std::istream& stream, T& reference) {
+  bool read_parameters(std::istream& stream, T& reference) {
 
     std::uint32_t header;
     header = read_little_endian<std::uint32_t>(stream);
-    if (!stream || header != T::GetHashValue()) return false;
+    if (!stream || header != T::get_hash_value()) return false;
-    return reference.ReadParameters(stream);
+    return reference.read_parameters(stream);
+  }
+
+  // Write evaluation function parameters
+  template <typename T>
+  bool write_parameters(std::ostream& stream, const T& reference) {
+
+    write_little_endian<std::uint32_t>(stream, T::get_hash_value());
+    return reference.write_parameters(stream);
   }
 
   }  // namespace Detail
 
   // Initialize the evaluation function parameters
-  void Initialize() {
+  void initialize() {
 
-    Detail::Initialize(feature_transformer);
+    Detail::initialize(featureTransformer);
-    Detail::Initialize(network);
+    for (std::size_t i = 0; i < LayerStacks; ++i)
+      Detail::initialize(network[i]);
   }
 
   // Read network header
-  bool ReadHeader(std::istream& stream, std::uint32_t* hash_value, std::string* architecture)
+  bool read_header(std::istream& stream, std::uint32_t* hashValue, std::string* desc)
   {
     std::uint32_t version, size;
 
     version     = read_little_endian<std::uint32_t>(stream);
-    *hash_value = read_little_endian<std::uint32_t>(stream);
+    *hashValue  = read_little_endian<std::uint32_t>(stream);
     size        = read_little_endian<std::uint32_t>(stream);
-    if (!stream || version != kVersion) return false;
+    if (!stream || version != Version) return false;
-    architecture->resize(size);
+    desc->resize(size);
-    stream.read(&(*architecture)[0], size);
+    stream.read(&(*desc)[0], size);
+    return !stream.fail();
+  }
+
+  // Write network header
+  bool write_header(std::ostream& stream, std::uint32_t hashValue, const std::string& desc)
+  {
+    write_little_endian<std::uint32_t>(stream, Version);
+    write_little_endian<std::uint32_t>(stream, hashValue);
+    write_little_endian<std::uint32_t>(stream, desc.size());
+    stream.write(&desc[0], desc.size());
     return !stream.fail();
   }
 
   // Read network parameters
-  bool ReadParameters(std::istream& stream) {
+  bool read_parameters(std::istream& stream) {
 
-    std::uint32_t hash_value;
+    std::uint32_t hashValue;
-    std::string architecture;
+    if (!read_header(stream, &hashValue, &netDescription)) return false;
-    if (!ReadHeader(stream, &hash_value, &architecture)) return false;
+    if (hashValue != HashValue) return false;
-    if (hash_value != kHashValue) return false;
+    if (!Detail::read_parameters(stream, *featureTransformer)) return false;
-    if (!Detail::ReadParameters(stream, *feature_transformer)) return false;
+    for (std::size_t i = 0; i < LayerStacks; ++i)
-    if (!Detail::ReadParameters(stream, *network)) return false;
+      if (!Detail::read_parameters(stream, *(network[i]))) return false;
     return stream && stream.peek() == std::ios::traits_type::eof();
   }
 
+  // Write network parameters
+  bool write_parameters(std::ostream& stream) {
+
+    if (!write_header(stream, HashValue, netDescription)) return false;
+    if (!Detail::write_parameters(stream, *featureTransformer)) return false;
+    for (std::size_t i = 0; i < LayerStacks; ++i)
+      if (!Detail::write_parameters(stream, *(network[i]))) return false;
+    return (bool)stream;
+  }
+
   // Evaluation function. Perform differential calculation.
-  Value evaluate(const Position& pos) {
+  Value evaluate(const Position& pos, bool adjusted) {
 
     // We manually align the arrays on the stack because with gcc < 9.3
     // overaligning stack variables with alignas() doesn't work correctly.
 
-    constexpr uint64_t alignment = kCacheLineSize;
+    constexpr uint64_t alignment = CacheLineSize;
+    int delta = 7;
 
 #if defined(ALIGNAS_ON_STACK_VARIABLES_BROKEN)
-    TransformedFeatureType transformed_features_unaligned[
+    TransformedFeatureType transformedFeaturesUnaligned[
-      FeatureTransformer::kBufferSize + alignment / sizeof(TransformedFeatureType)];
+      FeatureTransformer::BufferSize + alignment / sizeof(TransformedFeatureType)];
-    char buffer_unaligned[Network::kBufferSize + alignment];
 
-    auto* transformed_features = align_ptr_up<alignment>(&transformed_features_unaligned[0]);
+    auto* transformedFeatures = align_ptr_up<alignment>(&transformedFeaturesUnaligned[0]);
-    auto* buffer = align_ptr_up<alignment>(&buffer_unaligned[0]);
 #else
     alignas(alignment)
-      TransformedFeatureType transformed_features[FeatureTransformer::kBufferSize];
+      TransformedFeatureType transformedFeatures[FeatureTransformer::BufferSize];
-    alignas(alignment) char buffer[Network::kBufferSize];
 #endif
 
-    ASSERT_ALIGNED(transformed_features, alignment);
+    ASSERT_ALIGNED(transformedFeatures, alignment);
-    ASSERT_ALIGNED(buffer, alignment);
 
-    feature_transformer->Transform(pos, transformed_features);
+    const std::size_t bucket = (pos.count<ALL_PIECES>() - 1) / 4;
-    const auto output = network->Propagate(transformed_features, buffer);
+    const auto psqt = featureTransformer->transform(pos, transformedFeatures, bucket);
+    const auto positional = network[bucket]->propagate(transformedFeatures);
 
-    return static_cast<Value>(output[0] / FV_SCALE);
+    // Give more value to positional evaluation when adjusted flag is set
+    if (adjusted)
+        return static_cast<Value>(((128 - delta) * psqt + (128 + delta) * positional) / 128 / OutputScale);
+    else
+        return static_cast<Value>((psqt + positional) / OutputScale);
   }
 
+  struct NnueEvalTrace {
+    static_assert(LayerStacks == PSQTBuckets);
+
+    Value psqt[LayerStacks];
+    Value positional[LayerStacks];
+    std::size_t correctBucket;
+  };
+
+  static NnueEvalTrace trace_evaluate(const Position& pos) {
+
+    // We manually align the arrays on the stack because with gcc < 9.3
+    // overaligning stack variables with alignas() doesn't work correctly.
+
+    constexpr uint64_t alignment = CacheLineSize;
+
+#if defined(ALIGNAS_ON_STACK_VARIABLES_BROKEN)
+    TransformedFeatureType transformedFeaturesUnaligned[
+      FeatureTransformer::BufferSize + alignment / sizeof(TransformedFeatureType)];
+
+    auto* transformedFeatures = align_ptr_up<alignment>(&transformedFeaturesUnaligned[0]);
+#else
+    alignas(alignment)
+      TransformedFeatureType transformedFeatures[FeatureTransformer::BufferSize];
+#endif
+
+    ASSERT_ALIGNED(transformedFeatures, alignment);
+
+    NnueEvalTrace t{};
+    t.correctBucket = (pos.count<ALL_PIECES>() - 1) / 4;
+    for (std::size_t bucket = 0; bucket < LayerStacks; ++bucket) {
+      const auto materialist = featureTransformer->transform(pos, transformedFeatures, bucket);
+      const auto positional = network[bucket]->propagate(transformedFeatures);
+
+      t.psqt[bucket] = static_cast<Value>( materialist / OutputScale );
+      t.positional[bucket] = static_cast<Value>( positional / OutputScale );
+    }
+
+    return t;
+  }
+
+  static const std::string PieceToChar(" PNBRQK  pnbrqk");
+
+
+  // format_cp_compact() converts a Value into (centi)pawns and writes it in a buffer.
+  // The buffer must have capacity for at least 5 chars.
+  static void format_cp_compact(Value v, char* buffer) {
+
+    buffer[0] = (v < 0 ? '-' : v > 0 ? '+' : ' ');
+
+    int cp = std::abs(100 * v / PawnValueEg);
+    if (cp >= 10000)
+    {
+        buffer[1] = '0' + cp / 10000; cp %= 10000;
+        buffer[2] = '0' + cp / 1000; cp %= 1000;
+        buffer[3] = '0' + cp / 100;
+        buffer[4] = ' ';
+    }
+    else if (cp >= 1000)
+    {
+        buffer[1] = '0' + cp / 1000; cp %= 1000;
+        buffer[2] = '0' + cp / 100; cp %= 100;
+        buffer[3] = '.';
+        buffer[4] = '0' + cp / 10;
+    }
+    else
+    {
+        buffer[1] = '0' + cp / 100; cp %= 100;
+        buffer[2] = '.';
+        buffer[3] = '0' + cp / 10; cp %= 10;
+        buffer[4] = '0' + cp / 1;
+    }
+  }
+
+
+  // format_cp_aligned_dot() converts a Value into (centi)pawns and writes it in a buffer,
+  // always keeping two decimals. The buffer must have capacity for at least 7 chars.
+  static void format_cp_aligned_dot(Value v, char* buffer) {
+
+    buffer[0] = (v < 0 ? '-' : v > 0 ? '+' : ' ');
+
+    double cp = 1.0 * std::abs(int(v)) / PawnValueEg;
+    sprintf(&buffer[1], "%6.2f", cp);
+  }
+
+
+  // trace() returns a string with the value of each piece on a board,
+  // and a table for (PSQT, Layers) values bucket by bucket.
+
+  std::string trace(Position& pos) {
+
+    std::stringstream ss;
+
+    char board[3*8+1][8*8+2];
+    std::memset(board, ' ', sizeof(board));
+    for (int row = 0; row < 3*8+1; ++row)
+      board[row][8*8+1] = '\0';
+
+    // A lambda to output one box of the board
+    auto writeSquare = [&board](File file, Rank rank, Piece pc, Value value) {
+
+      const int x = ((int)file) * 8;
+      const int y = (7 - (int)rank) * 3;
+      for (int i = 1; i < 8; ++i)
+         board[y][x+i] = board[y+3][x+i] = '-';
+      for (int i = 1; i < 3; ++i)
+         board[y+i][x] = board[y+i][x+8] = '|';
+      board[y][x] = board[y][x+8] = board[y+3][x+8] = board[y+3][x] = '+';
+      if (pc != NO_PIECE)
+        board[y+1][x+4] = PieceToChar[pc];
+      if (value != VALUE_NONE)
+        format_cp_compact(value, &board[y+2][x+2]);
+    };
+
+    // We estimate the value of each piece by doing a differential evaluation from
+    // the current base eval, simulating the removal of the piece from its square.
+    Value base = evaluate(pos);
+    base = pos.side_to_move() == WHITE ? base : -base;
+
+    for (File f = FILE_A; f <= FILE_H; ++f)
+      for (Rank r = RANK_1; r <= RANK_8; ++r)
+      {
+        Square sq = make_square(f, r);
+        Piece pc = pos.piece_on(sq);
+        Value v = VALUE_NONE;
+
+        if (pc != NO_PIECE && type_of(pc) != KING)
+        {
+          auto st = pos.state();
+
+          pos.remove_piece(sq);
+          st->accumulator.computed[WHITE] = false;
+          st->accumulator.computed[BLACK] = false;
+
+          Value eval = evaluate(pos);
+          eval = pos.side_to_move() == WHITE ? eval : -eval;
+          v = base - eval;
+
+          pos.put_piece(pc, sq);
+          st->accumulator.computed[WHITE] = false;
+          st->accumulator.computed[BLACK] = false;
+        }
+
+        writeSquare(f, r, pc, v);
+      }
+
+    ss << " NNUE derived piece values:\n";
+    for (int row = 0; row < 3*8+1; ++row)
+        ss << board[row] << '\n';
+    ss << '\n';
+
+    auto t = trace_evaluate(pos);
+
+    ss << " NNUE network contributions "
+       << (pos.side_to_move() == WHITE ? "(White to move)" : "(Black to move)") << std::endl
+       << "+------------+------------+------------+------------+\n"
+       << "|   Bucket   |  Material  | Positional |   Total    |\n"
+       << "|            |   (PSQT)   |  (Layers)  |            |\n"
+       << "+------------+------------+------------+------------+\n";
+
+    for (std::size_t bucket = 0; bucket < LayerStacks; ++bucket)
+    {
+      char buffer[3][8];
+      std::memset(buffer, '\0', sizeof(buffer));
+
+      format_cp_aligned_dot(t.psqt[bucket], buffer[0]);
+      format_cp_aligned_dot(t.positional[bucket], buffer[1]);
+      format_cp_aligned_dot(t.psqt[bucket] + t.positional[bucket], buffer[2]);
+
+      ss <<  "|  " << bucket    << "        "
+         << " |  " << buffer[0] << "  "
+         << " |  " << buffer[1] << "  "
+         << " |  " << buffer[2] << "  "
+         << " |";
+      if (bucket == t.correctBucket)
+          ss << " <-- this bucket is used";
+      ss << '\n';
+    }
+
+    ss << "+------------+------------+------------+------------+\n";
+
+    return ss.str();
+  }
+
+
   // Load eval, from a file stream or a memory stream
   bool load_eval(std::string name, std::istream& stream) {
 
-    Initialize();
+    initialize();
     fileName = name;
-    return ReadParameters(stream);
+    return read_parameters(stream);
   }
 
-} // namespace Eval::NNUE
+  // Save eval, to a file stream or a memory stream
+  bool save_eval(std::ostream& stream) {
+
+    if (fileName.empty())
+      return false;
+
+    return write_parameters(stream);
+  }
+
+  /// Save eval, to a file given by its name
+  bool save_eval(const std::optional<std::string>& filename) {
+
+    std::string actualFilename;
+    std::string msg;
+
+    if (filename.has_value())
+        actualFilename = filename.value();
+    else
+    {
+        if (currentEvalFileName != EvalFileDefaultName)
+        {
+             msg = "Failed to export a net. A non-embedded net can only be saved if the filename is specified";
+
+             sync_cout << msg << sync_endl;
+             return false;
+        }
+        actualFilename = EvalFileDefaultName;
+    }
+
+    std::ofstream stream(actualFilename, std::ios_base::binary);
+    bool saved = save_eval(stream);
+
+    msg = saved ? "Network saved successfully to " + actualFilename
+                : "Failed to export a net";
+
+    sync_cout << msg << sync_endl;
+    return saved;
+  }
+
+
+} // namespace Stockfish::Eval::NNUE

src/nnue/evaluate_nnue.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -25,11 +25,11 @@
 
 #include <memory>
 
-namespace Eval::NNUE {
+namespace Stockfish::Eval::NNUE {
 
   // Hash value of evaluation function structure
-  constexpr std::uint32_t kHashValue =
+  constexpr std::uint32_t HashValue =
-      FeatureTransformer::GetHashValue() ^ Network::GetHashValue();
+      FeatureTransformer::get_hash_value() ^ Network::get_hash_value();
 
   // Deleter for automating release of memory area
   template <typename T>
@@ -54,6 +54,6 @@ namespace Eval::NNUE {
   template <typename T>
   using LargePagePtr = std::unique_ptr<T, LargePageDeleter<T>>;
 
-}  // namespace Eval::NNUE
+}  // namespace Stockfish::Eval::NNUE
 
 #endif // #ifndef NNUE_EVALUATE_NNUE_H_INCLUDED

src/nnue/features/feature_set.h

@@ -1,69 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-// A class template that represents the input feature set of the NNUE evaluation function
-
-#ifndef NNUE_FEATURE_SET_H_INCLUDED
-#define NNUE_FEATURE_SET_H_INCLUDED
-
-#include "features_common.h"
-#include <array>
-
-namespace Eval::NNUE::Features {
-
-  // Class template that represents a list of values
-  template <typename T, T... Values>
-  struct CompileTimeList;
-
-  template <typename T, T First, T... Remaining>
-  struct CompileTimeList<T, First, Remaining...> {
-    static constexpr bool Contains(T value) {
-      return value == First || CompileTimeList<T, Remaining...>::Contains(value);
-    }
-    static constexpr std::array<T, sizeof...(Remaining) + 1>
-        kValues = {{First, Remaining...}};
-  };
-
-  // Base class of feature set
-  template <typename Derived>
-  class FeatureSetBase {
-
-  };
-
-  // Class template that represents the feature set
-  template <typename FeatureType>
-  class FeatureSet<FeatureType> : public FeatureSetBase<FeatureSet<FeatureType>> {
-
-   public:
-    // Hash value embedded in the evaluation file
-    static constexpr std::uint32_t kHashValue = FeatureType::kHashValue;
-    // Number of feature dimensions
-    static constexpr IndexType kDimensions = FeatureType::kDimensions;
-    // Maximum number of simultaneously active features
-    static constexpr IndexType kMaxActiveDimensions =
-        FeatureType::kMaxActiveDimensions;
-    // Trigger for full calculation instead of difference calculation
-    using SortedTriggerSet =
-        CompileTimeList<TriggerEvent, FeatureType::kRefreshTrigger>;
-    static constexpr auto kRefreshTriggers = SortedTriggerSet::kValues;
-
-  };
-
-}  // namespace Eval::NNUE::Features
-
-#endif // #ifndef NNUE_FEATURE_SET_H_INCLUDED

src/nnue/features/features_common.h

@@ -1,45 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-//Common header of input features of NNUE evaluation function
-
-#ifndef NNUE_FEATURES_COMMON_H_INCLUDED
-#define NNUE_FEATURES_COMMON_H_INCLUDED
-
-#include "../../evaluate.h"
-#include "../nnue_common.h"
-
-namespace Eval::NNUE::Features {
-
-  class IndexList;
-
-  template <typename... FeatureTypes>
-  class FeatureSet;
-
-  // Trigger to perform full calculations instead of difference only
-  enum class TriggerEvent {
-    kFriendKingMoved // calculate full evaluation when own king moves
-  };
-
-  enum class Side {
-    kFriend // side to move
-  };
-
-}  // namespace Eval::NNUE::Features
-
-#endif // #ifndef NNUE_FEATURES_COMMON_H_INCLUDED

src/nnue/features/half_ka_v2_hm.cpp

@@ -0,0 +1,83 @@
+/*
+  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
+
+  Stockfish is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  Stockfish is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+//Definition of input features HalfKAv2_hm of NNUE evaluation function
+
+#include "half_ka_v2_hm.h"
+
+#include "../../position.h"
+
+namespace Stockfish::Eval::NNUE::Features {
+
+  // Orient a square according to perspective (rotates by 180 for black)
+  inline Square HalfKAv2_hm::orient(Color perspective, Square s, Square ksq) {
+    return Square(int(s) ^ (bool(perspective) * SQ_A8) ^ ((file_of(ksq) < FILE_E) * SQ_H1));
+  }
+
+  // Index of a feature for a given king position and another piece on some square
+  inline IndexType HalfKAv2_hm::make_index(Color perspective, Square s, Piece pc, Square ksq) {
+    Square o_ksq = orient(perspective, ksq, ksq);
+    return IndexType(orient(perspective, s, ksq) + PieceSquareIndex[perspective][pc] + PS_NB * KingBuckets[o_ksq]);
+  }
+
+  // Get a list of indices for active features
+  void HalfKAv2_hm::append_active_indices(
+    const Position& pos,
+    Color perspective,
+    IndexList& active
+  ) {
+    Square ksq = pos.square<KING>(perspective);
+    Bitboard bb = pos.pieces();
+    while (bb)
+    {
+      Square s = pop_lsb(bb);
+      active.push_back(make_index(perspective, s, pos.piece_on(s), ksq));
+    }
+  }
+
+
+  // append_changed_indices() : get a list of indices for recently changed features
+
+  void HalfKAv2_hm::append_changed_indices(
+    Square ksq,
+    const DirtyPiece& dp,
+    Color perspective,
+    IndexList& removed,
+    IndexList& added
+  ) {
+    for (int i = 0; i < dp.dirty_num; ++i) {
+      if (dp.from[i] != SQ_NONE)
+        removed.push_back(make_index(perspective, dp.from[i], dp.piece[i], ksq));
+      if (dp.to[i] != SQ_NONE)
+        added.push_back(make_index(perspective, dp.to[i], dp.piece[i], ksq));
+    }
+  }
+
+  int HalfKAv2_hm::update_cost(const StateInfo* st) {
+    return st->dirtyPiece.dirty_num;
+  }
+
+  int HalfKAv2_hm::refresh_cost(const Position& pos) {
+    return pos.count<ALL_PIECES>();
+  }
+
+  bool HalfKAv2_hm::requires_refresh(const StateInfo* st, Color perspective) {
+    return st->dirtyPiece.piece[0] == make_piece(perspective, KING);
+  }
+
+}  // namespace Stockfish::Eval::NNUE::Features

src/nnue/features/half_ka_v2_hm.h

@@ -0,0 +1,124 @@
+/*
+  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
+
+  Stockfish is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  Stockfish is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+//Definition of input features HalfKP of NNUE evaluation function
+
+#ifndef NNUE_FEATURES_HALF_KA_V2_HM_H_INCLUDED
+#define NNUE_FEATURES_HALF_KA_V2_HM_H_INCLUDED
+
+#include "../nnue_common.h"
+
+#include "../../evaluate.h"
+#include "../../misc.h"
+
+namespace Stockfish {
+  struct StateInfo;
+}
+
+namespace Stockfish::Eval::NNUE::Features {
+
+  // Feature HalfKAv2_hm: Combination of the position of own king
+  // and the position of pieces. Position mirrored such that king always on e..h files.
+  class HalfKAv2_hm {
+
+    // unique number for each piece type on each square
+    enum {
+      PS_NONE     =  0,
+      PS_W_PAWN   =  0,
+      PS_B_PAWN   =  1 * SQUARE_NB,
+      PS_W_KNIGHT =  2 * SQUARE_NB,
+      PS_B_KNIGHT =  3 * SQUARE_NB,
+      PS_W_BISHOP =  4 * SQUARE_NB,
+      PS_B_BISHOP =  5 * SQUARE_NB,
+      PS_W_ROOK   =  6 * SQUARE_NB,
+      PS_B_ROOK   =  7 * SQUARE_NB,
+      PS_W_QUEEN  =  8 * SQUARE_NB,
+      PS_B_QUEEN  =  9 * SQUARE_NB,
+      PS_KING     =  10 * SQUARE_NB,
+      PS_NB       =  11 * SQUARE_NB
+    };
+
+    static constexpr IndexType PieceSquareIndex[COLOR_NB][PIECE_NB] = {
+      // convention: W - us, B - them
+      // viewed from other side, W and B are reversed
+      { PS_NONE, PS_W_PAWN, PS_W_KNIGHT, PS_W_BISHOP, PS_W_ROOK, PS_W_QUEEN, PS_KING, PS_NONE,
+        PS_NONE, PS_B_PAWN, PS_B_KNIGHT, PS_B_BISHOP, PS_B_ROOK, PS_B_QUEEN, PS_KING, PS_NONE },
+      { PS_NONE, PS_B_PAWN, PS_B_KNIGHT, PS_B_BISHOP, PS_B_ROOK, PS_B_QUEEN, PS_KING, PS_NONE,
+        PS_NONE, PS_W_PAWN, PS_W_KNIGHT, PS_W_BISHOP, PS_W_ROOK, PS_W_QUEEN, PS_KING, PS_NONE }
+    };
+
+    // Orient a square according to perspective (rotates by 180 for black)
+    static Square orient(Color perspective, Square s, Square ksq);
+
+    // Index of a feature for a given king position and another piece on some square
+    static IndexType make_index(Color perspective, Square s, Piece pc, Square ksq);
+
+   public:
+    // Feature name
+    static constexpr const char* Name = "HalfKAv2_hm(Friend)";
+
+    // Hash value embedded in the evaluation file
+    static constexpr std::uint32_t HashValue = 0x7f234cb8u;
+
+    // Number of feature dimensions
+    static constexpr IndexType Dimensions =
+        static_cast<IndexType>(SQUARE_NB) * static_cast<IndexType>(PS_NB) / 2;
+
+    static constexpr int KingBuckets[64] = {
+      -1, -1, -1, -1, 31, 30, 29, 28,
+      -1, -1, -1, -1, 27, 26, 25, 24,
+      -1, -1, -1, -1, 23, 22, 21, 20,
+      -1, -1, -1, -1, 19, 18, 17, 16,
+      -1, -1, -1, -1, 15, 14, 13, 12,
+      -1, -1, -1, -1, 11, 10,  9,  8,
+      -1, -1, -1, -1,  7,  6,  5,  4,
+      -1, -1, -1, -1,  3,  2,  1,  0
+    };
+
+    // Maximum number of simultaneously active features.
+    static constexpr IndexType MaxActiveDimensions = 32;
+    using IndexList = ValueList<IndexType, MaxActiveDimensions>;
+
+    // Get a list of indices for active features
+    static void append_active_indices(
+      const Position& pos,
+      Color perspective,
+      IndexList& active);
+
+    // Get a list of indices for recently changed features
+    static void append_changed_indices(
+      Square ksq,
+      const DirtyPiece& dp,
+      Color perspective,
+      IndexList& removed,
+      IndexList& added
+    );
+
+    // Returns the cost of updating one perspective, the most costly one.
+    // Assumes no refresh needed.
+    static int update_cost(const StateInfo* st);
+    static int refresh_cost(const Position& pos);
+
+    // Returns whether the change stored in this StateInfo means that
+    // a full accumulator refresh is required.
+    static bool requires_refresh(const StateInfo* st, Color perspective);
+  };
+
+}  // namespace Stockfish::Eval::NNUE::Features
+
+#endif // #ifndef NNUE_FEATURES_HALF_KA_V2_HM_H_INCLUDED

src/nnue/features/half_kp.cpp

@@ -1,68 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-//Definition of input features HalfKP of NNUE evaluation function
-
-#include "half_kp.h"
-#include "index_list.h"
-
-namespace Eval::NNUE::Features {
-
-  // Orient a square according to perspective (rotates by 180 for black)
-  inline Square orient(Color perspective, Square s) {
-    return Square(int(s) ^ (bool(perspective) * 63));
-  }
-
-  // Index of a feature for a given king position and another piece on some square
-  inline IndexType make_index(Color perspective, Square s, Piece pc, Square ksq) {
-    return IndexType(orient(perspective, s) + kpp_board_index[perspective][pc] + PS_END * ksq);
-  }
-
-  // Get a list of indices for active features
-  template <Side AssociatedKing>
-  void HalfKP<AssociatedKing>::AppendActiveIndices(
-      const Position& pos, Color perspective, IndexList* active) {
-
-    Square ksq = orient(perspective, pos.square<KING>(perspective));
-    Bitboard bb = pos.pieces() & ~pos.pieces(KING);
-    while (bb) {
-      Square s = pop_lsb(&bb);
-      active->push_back(make_index(perspective, s, pos.piece_on(s), ksq));
-    }
-  }
-
-  // Get a list of indices for recently changed features
-  template <Side AssociatedKing>
-  void HalfKP<AssociatedKing>::AppendChangedIndices(
-      const Position& pos, const DirtyPiece& dp, Color perspective,
-      IndexList* removed, IndexList* added) {
-
-    Square ksq = orient(perspective, pos.square<KING>(perspective));
-    for (int i = 0; i < dp.dirty_num; ++i) {
-      Piece pc = dp.piece[i];
-      if (type_of(pc) == KING) continue;
-      if (dp.from[i] != SQ_NONE)
-        removed->push_back(make_index(perspective, dp.from[i], pc, ksq));
-      if (dp.to[i] != SQ_NONE)
-        added->push_back(make_index(perspective, dp.to[i], pc, ksq));
-    }
-  }
-
-  template class HalfKP<Side::kFriend>;
-
-}  // namespace Eval::NNUE::Features

src/nnue/features/half_kp.h

@@ -1,59 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-//Definition of input features HalfKP of NNUE evaluation function
-
-#ifndef NNUE_FEATURES_HALF_KP_H_INCLUDED
-#define NNUE_FEATURES_HALF_KP_H_INCLUDED
-
-#include "../../evaluate.h"
-#include "features_common.h"
-
-namespace Eval::NNUE::Features {
-
-  // Feature HalfKP: Combination of the position of own king
-  // and the position of pieces other than kings
-  template <Side AssociatedKing>
-  class HalfKP {
-
-   public:
-    // Feature name
-    static constexpr const char* kName = "HalfKP(Friend)";
-    // Hash value embedded in the evaluation file
-    static constexpr std::uint32_t kHashValue =
-        0x5D69D5B9u ^ (AssociatedKing == Side::kFriend);
-    // Number of feature dimensions
-    static constexpr IndexType kDimensions =
-        static_cast<IndexType>(SQUARE_NB) * static_cast<IndexType>(PS_END);
-    // Maximum number of simultaneously active features
-    static constexpr IndexType kMaxActiveDimensions = 30; // Kings don't count
-    // Trigger for full calculation instead of difference calculation
-    static constexpr TriggerEvent kRefreshTrigger = TriggerEvent::kFriendKingMoved;
-
-    // Get a list of indices for active features
-    static void AppendActiveIndices(const Position& pos, Color perspective,
-                                    IndexList* active);
-
-    // Get a list of indices for recently changed features
-    static void AppendChangedIndices(const Position& pos, const DirtyPiece& dp, Color perspective,
-                                     IndexList* removed, IndexList* added);
-  };
-
-}  // namespace Eval::NNUE::Features
-
-#endif // #ifndef NNUE_FEATURES_HALF_KP_H_INCLUDED

src/nnue/features/index_list.h

@@ -1,64 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-// Definition of index list of input features
-
-#ifndef NNUE_FEATURES_INDEX_LIST_H_INCLUDED
-#define NNUE_FEATURES_INDEX_LIST_H_INCLUDED
-
-#include "../../position.h"
-#include "../nnue_architecture.h"
-
-namespace Eval::NNUE::Features {
-
-  // Class template used for feature index list
-  template <typename T, std::size_t MaxSize>
-  class ValueList {
-
-   public:
-    std::size_t size() const { return size_; }
-    void resize(std::size_t size) { size_ = size; }
-    void push_back(const T& value) { values_[size_++] = value; }
-    T& operator[](std::size_t index) { return values_[index]; }
-    T* begin() { return values_; }
-    T* end() { return values_ + size_; }
-    const T& operator[](std::size_t index) const { return values_[index]; }
-    const T* begin() const { return values_; }
-    const T* end() const { return values_ + size_; }
-
-    void swap(ValueList& other) {
-      const std::size_t max_size = std::max(size_, other.size_);
-      for (std::size_t i = 0; i < max_size; ++i) {
-        std::swap(values_[i], other.values_[i]);
-      }
-      std::swap(size_, other.size_);
-    }
-
-   private:
-    T values_[MaxSize];
-    std::size_t size_ = 0;
-  };
-
-  //Type of feature index list
-  class IndexList
-      : public ValueList<IndexType, RawFeatures::kMaxActiveDimensions> {
-  };
-
-}  // namespace Eval::NNUE::Features
-
-#endif // NNUE_FEATURES_INDEX_LIST_H_INCLUDED

src/nnue/layers/affine_transform.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -22,410 +22,338 @@
 #define NNUE_LAYERS_AFFINE_TRANSFORM_H_INCLUDED
 
 #include <iostream>
+#include <algorithm>
+#include <type_traits>
 #include "../nnue_common.h"
+#include "../../simd.h"
 
-namespace Eval::NNUE::Layers {
+/*
+  This file contains the definition for a fully connected layer (aka affine transform).
+  Two approaches are employed, depending on the sizes of the transform.
 
-  // Affine transformation layer
+  Approach 1:
-  template <typename PreviousLayer, IndexType OutputDimensions>
+    - used when the PaddedInputDimensions >= 128
-  class AffineTransform {
+    - uses AVX512 if possible
-   public:
+    - processes inputs in batches of 2*InputSimdWidth
-    // Input/output type
+      - so in batches of 128 for AVX512
-    using InputType = typename PreviousLayer::OutputType;
+    - the weight blocks of size InputSimdWidth are transposed such that
-    using OutputType = std::int32_t;
+      access is sequential
-    static_assert(std::is_same<InputType, std::uint8_t>::value, "");
+    - N columns of the weight matrix are processed a time, where N
+      depends on the architecture (the amount of registers)
+    - accumulate + hadd is used
 
-    // Number of input/output dimensions
+  Approach 2:
-    static constexpr IndexType kInputDimensions =
+    - used when the PaddedInputDimensions < 128
-        PreviousLayer::kOutputDimensions;
+    - does not use AVX512
-    static constexpr IndexType kOutputDimensions = OutputDimensions;
+    - expected use-case is for when PaddedInputDimensions == 32 and InputDimensions <= 32.
-    static constexpr IndexType kPaddedInputDimensions =
+      - that's why AVX512 is hard to implement
-        CeilToMultiple<IndexType>(kInputDimensions, kMaxSimdWidth);
+    - expected use-case is small layers
-#if defined (USE_AVX512)
+      - not optimized as well as the approach 1
-    static constexpr const IndexType kOutputSimdWidth = kSimdWidth / 2;
+    - inputs are processed in chunks of 4, weights are respectively transposed
-#elif defined (USE_SSSE3)
+    - accumulation happens directly to int32s
-    static constexpr const IndexType kOutputSimdWidth = kSimdWidth / 4;
+*/
-#endif
 
-    // Size of forward propagation buffer used in this layer
+namespace Stockfish::Eval::NNUE::Layers {
-    static constexpr std::size_t kSelfBufferSize =
-        CeilToMultiple(kOutputDimensions * sizeof(OutputType), kCacheLineSize);
 
-    // Size of the forward propagation buffer used from the input layer to this layer
+// Fallback implementation for older/other architectures.
-    static constexpr std::size_t kBufferSize =
+// Identical for both approaches. Requires the input to be padded to at least 16 values.
-        PreviousLayer::kBufferSize + kSelfBufferSize;
+#if !defined(USE_SSSE3)
+  template <IndexType InputDimensions, IndexType PaddedInputDimensions, IndexType OutputDimensions>
+  static void affine_transform_non_ssse3(std::int32_t* output, const std::int8_t* weights, const std::int32_t* biases, const std::uint8_t* input)
+  {
+# if defined(USE_SSE2)
+    // At least a multiple of 16, with SSE2.
+    constexpr IndexType NumChunks = ceil_to_multiple<IndexType>(InputDimensions, 16) / 16;
+    const __m128i Zeros = _mm_setzero_si128();
+    const auto inputVector = reinterpret_cast<const __m128i*>(input);
 
-    // Hash value embedded in the evaluation file
+# elif defined(USE_MMX)
-    static constexpr std::uint32_t GetHashValue() {
+    constexpr IndexType NumChunks = ceil_to_multiple<IndexType>(InputDimensions, 8) / 8;
-      std::uint32_t hash_value = 0xCC03DAE4u;
+    const __m64 Zeros = _mm_setzero_si64();
-      hash_value += kOutputDimensions;
+    const auto inputVector = reinterpret_cast<const __m64*>(input);
-      hash_value ^= PreviousLayer::GetHashValue() >> 1;
+
-      hash_value ^= PreviousLayer::GetHashValue() << 31;
+# elif defined(USE_NEON)
-      return hash_value;
+    constexpr IndexType NumChunks = ceil_to_multiple<IndexType>(InputDimensions, 16) / 16;
+    const auto inputVector = reinterpret_cast<const int8x8_t*>(input);
+# endif
+
+    for (IndexType i = 0; i < OutputDimensions; ++i) {
+      const IndexType offset = i * PaddedInputDimensions;
+
+# if defined(USE_SSE2)
+      __m128i sumLo = _mm_cvtsi32_si128(biases[i]);
+      __m128i sumHi = Zeros;
+      const auto row = reinterpret_cast<const __m128i*>(&weights[offset]);
+      for (IndexType j = 0; j < NumChunks; ++j) {
+        __m128i row_j = _mm_load_si128(&row[j]);
+        __m128i input_j = _mm_load_si128(&inputVector[j]);
+        __m128i extendedRowLo = _mm_srai_epi16(_mm_unpacklo_epi8(row_j, row_j), 8);
+        __m128i extendedRowHi = _mm_srai_epi16(_mm_unpackhi_epi8(row_j, row_j), 8);
+        __m128i extendedInputLo = _mm_unpacklo_epi8(input_j, Zeros);
+        __m128i extendedInputHi = _mm_unpackhi_epi8(input_j, Zeros);
+        __m128i productLo = _mm_madd_epi16(extendedRowLo, extendedInputLo);
+        __m128i productHi = _mm_madd_epi16(extendedRowHi, extendedInputHi);
+        sumLo = _mm_add_epi32(sumLo, productLo);
+        sumHi = _mm_add_epi32(sumHi, productHi);
+      }
+      __m128i sum = _mm_add_epi32(sumLo, sumHi);
+      __m128i sumHigh_64 = _mm_shuffle_epi32(sum, _MM_SHUFFLE(1, 0, 3, 2));
+      sum = _mm_add_epi32(sum, sumHigh_64);
+      __m128i sum_second_32 = _mm_shufflelo_epi16(sum, _MM_SHUFFLE(1, 0, 3, 2));
+      sum = _mm_add_epi32(sum, sum_second_32);
+      output[i] = _mm_cvtsi128_si32(sum);
+
+# elif defined(USE_MMX)
+      __m64 sumLo = _mm_cvtsi32_si64(biases[i]);
+      __m64 sumHi = Zeros;
+      const auto row = reinterpret_cast<const __m64*>(&weights[offset]);
+      for (IndexType j = 0; j < NumChunks; ++j) {
+        __m64 row_j = row[j];
+        __m64 input_j = inputVector[j];
+        __m64 extendedRowLo = _mm_srai_pi16(_mm_unpacklo_pi8(row_j, row_j), 8);
+        __m64 extendedRowHi = _mm_srai_pi16(_mm_unpackhi_pi8(row_j, row_j), 8);
+        __m64 extendedInputLo = _mm_unpacklo_pi8(input_j, Zeros);
+        __m64 extendedInputHi = _mm_unpackhi_pi8(input_j, Zeros);
+        __m64 productLo = _mm_madd_pi16(extendedRowLo, extendedInputLo);
+        __m64 productHi = _mm_madd_pi16(extendedRowHi, extendedInputHi);
+        sumLo = _mm_add_pi32(sumLo, productLo);
+        sumHi = _mm_add_pi32(sumHi, productHi);
+      }
+      __m64 sum = _mm_add_pi32(sumLo, sumHi);
+      sum = _mm_add_pi32(sum, _mm_unpackhi_pi32(sum, sum));
+      output[i] = _mm_cvtsi64_si32(sum);
+
+# elif defined(USE_NEON)
+      int32x4_t sum = {biases[i]};
+      const auto row = reinterpret_cast<const int8x8_t*>(&weights[offset]);
+      for (IndexType j = 0; j < NumChunks; ++j) {
+        int16x8_t product = vmull_s8(inputVector[j * 2], row[j * 2]);
+        product = vmlal_s8(product, inputVector[j * 2 + 1], row[j * 2 + 1]);
+        sum = vpadalq_s16(sum, product);
+      }
+      output[i] = sum[0] + sum[1] + sum[2] + sum[3];
+
+# else
+      std::int32_t sum = biases[i];
+      for (IndexType j = 0; j < InputDimensions; ++j) {
+        sum += weights[offset + j] * input[j];
+      }
+      output[i] = sum;
+# endif
     }
 
-   // Read network parameters
+# if defined(USE_MMX)
-    bool ReadParameters(std::istream& stream) {
+    _mm_empty();
-      if (!previous_layer_.ReadParameters(stream)) return false;
+# endif
-      for (std::size_t i = 0; i < kOutputDimensions; ++i)
+  }
-        biases_[i] = read_little_endian<BiasType>(stream);
+#endif
-      for (std::size_t i = 0; i < kOutputDimensions * kPaddedInputDimensions; ++i)
+
-#if !defined (USE_SSSE3)
+  template <IndexType InDims, IndexType OutDims, typename Enabled = void>
-        weights_[i] = read_little_endian<WeightType>(stream);
+  class AffineTransform;
+
+  // A specialization for large inputs.
+  template <IndexType InDims, IndexType OutDims>
+  class AffineTransform<InDims, OutDims, std::enable_if_t<(ceil_to_multiple<IndexType>(InDims, MaxSimdWidth) >= 2*64)>> {
+   public:
+    // Input/output type
+    using InputType = std::uint8_t;
+    using OutputType = std::int32_t;
+
+    // Number of input/output dimensions
+    static constexpr IndexType InputDimensions = InDims;
+    static constexpr IndexType OutputDimensions = OutDims;
+
+    static constexpr IndexType PaddedInputDimensions =
+      ceil_to_multiple<IndexType>(InputDimensions, MaxSimdWidth);
+    static constexpr IndexType PaddedOutputDimensions =
+      ceil_to_multiple<IndexType>(OutputDimensions, MaxSimdWidth);
+
+    using OutputBuffer = OutputType[PaddedOutputDimensions];
+
+    static_assert(PaddedInputDimensions >= 128, "Something went wrong. This specialization should not have been chosen.");
+
+#if defined (USE_AVX512)
+    static constexpr const IndexType InputSimdWidth = 64;
+    static constexpr const IndexType MaxNumOutputRegs = 16;
+#elif defined (USE_AVX2)
+    static constexpr const IndexType InputSimdWidth = 32;
+    static constexpr const IndexType MaxNumOutputRegs = 8;
+#elif defined (USE_SSSE3)
+    static constexpr const IndexType InputSimdWidth = 16;
+    static constexpr const IndexType MaxNumOutputRegs = 8;
+#elif defined (USE_NEON)
+    static constexpr const IndexType InputSimdWidth = 8;
+    static constexpr const IndexType MaxNumOutputRegs = 8;
 #else
-        weights_[
+    // The fallback implementation will not have permuted weights.
-          (i / 4) % (kPaddedInputDimensions / 4) * kOutputDimensions * 4 +
+    // We define these to avoid a lot of ifdefs later.
-          i / kPaddedInputDimensions * 4 +
+    static constexpr const IndexType InputSimdWidth = 1;
-          i % 4
+    static constexpr const IndexType MaxNumOutputRegs = 1;
-        ] = read_little_endian<WeightType>(stream);
-
-      // Determine if eights of weight and input products can be summed using 16bits
-      // without saturation. We assume worst case combinations of 0 and 127 for all inputs.
-      if (kOutputDimensions > 1 && !stream.fail())
-      {
-          canSaturate16.count = 0;
-#if !defined(USE_VNNI)
-          for (IndexType i = 0; i < kPaddedInputDimensions; i += 16)
-              for (IndexType j = 0; j < kOutputDimensions; ++j)
-                  for (int x = 0; x < 2; ++x)
-                  {
-                      WeightType* w = &weights_[i * kOutputDimensions + j * 4 + x * 2];
-                      int sum[2] = {0, 0};
-                      for (int k = 0; k < 8; ++k)
-                      {
-                          IndexType idx = k / 2 * kOutputDimensions * 4 + k % 2;
-                          sum[w[idx] < 0] += w[idx];
-                      }
-                      for (int sign : {-1, 1})
-                          while (sign * sum[sign == -1] > 258)
-                          {
-                              int maxK = 0, maxW = 0;
-                              for (int k = 0; k < 8; ++k)
-                              {
-                                  IndexType idx = k / 2 * kOutputDimensions * 4 + k % 2;
-                                  if (maxW < sign * w[idx])
-                                      maxK = k, maxW = sign * w[idx];
-                              }
-
-                              IndexType idx = maxK / 2 * kOutputDimensions * 4 + maxK % 2;
-                              sum[sign == -1] -= w[idx];
-                              canSaturate16.add(j, i + maxK / 2 * 4 + maxK % 2 + x * 2, w[idx]);
-                              w[idx] = 0;
-                          }
-                  }
-
-          // Non functional optimization for faster more linear access
-          std::sort(canSaturate16.ids, canSaturate16.ids + canSaturate16.count,
-                    [](const typename CanSaturate::Entry& e1, const typename CanSaturate::Entry& e2)
-                    { return e1.in == e2.in ? e1.out < e2.out : e1.in < e2.in; });
-#endif
-      }
 #endif
 
+    // A big block is a region in the weight matrix of the size [PaddedInputDimensions, NumOutputRegs].
+    // A small block is a region of size [InputSimdWidth, 1]
+
+    static constexpr const IndexType NumOutputRegs = std::min(MaxNumOutputRegs, OutputDimensions);
+    static constexpr const IndexType SmallBlockSize = InputSimdWidth;
+    static constexpr const IndexType BigBlockSize = NumOutputRegs * PaddedInputDimensions;
+    static constexpr const IndexType NumSmallBlocksInBigBlock = BigBlockSize / SmallBlockSize;
+    static constexpr const IndexType NumSmallBlocksPerOutput = PaddedInputDimensions / SmallBlockSize;
+    static constexpr const IndexType NumBigBlocks = OutputDimensions / NumOutputRegs;
+
+    static_assert(OutputDimensions % NumOutputRegs == 0);
+
+    // Hash value embedded in the evaluation file
+    static constexpr std::uint32_t get_hash_value(std::uint32_t prevHash) {
+      std::uint32_t hashValue = 0xCC03DAE4u;
+      hashValue += OutputDimensions;
+      hashValue ^= prevHash >> 1;
+      hashValue ^= prevHash << 31;
+      return hashValue;
+    }
+
+    /*
+      Transposes the small blocks within a block.
+      Effectively means that weights can be traversed sequentially during inference.
+    */
+    static IndexType get_weight_index(IndexType i)
+    {
+      const IndexType smallBlock = (i / SmallBlockSize) % NumSmallBlocksInBigBlock;
+      const IndexType smallBlockCol = smallBlock / NumSmallBlocksPerOutput;
+      const IndexType smallBlockRow = smallBlock % NumSmallBlocksPerOutput;
+      const IndexType bigBlock   = i / BigBlockSize;
+      const IndexType rest       = i % SmallBlockSize;
+
+      const IndexType idx =
+          bigBlock * BigBlockSize
+        + smallBlockRow * SmallBlockSize * NumOutputRegs
+        + smallBlockCol * SmallBlockSize
+        + rest;
+
+      return idx;
+    }
+
+    // Read network parameters
+    bool read_parameters(std::istream& stream) {
+      for (std::size_t i = 0; i < OutputDimensions; ++i)
+        biases[i] = read_little_endian<BiasType>(stream);
+
+      for (std::size_t i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
+        weights[get_weight_index(i)] = read_little_endian<WeightType>(stream);
+
+      return !stream.fail();
+    }
+
+    // Write network parameters
+    bool write_parameters(std::ostream& stream) const {
+      for (std::size_t i = 0; i < OutputDimensions; ++i)
+          write_little_endian<BiasType>(stream, biases[i]);
+
+      for (std::size_t i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
+        write_little_endian<WeightType>(stream, weights[get_weight_index(i)]);
+
       return !stream.fail();
     }
 
     // Forward propagation
-    const OutputType* Propagate(
+    const OutputType* propagate(
-        const TransformedFeatureType* transformed_features, char* buffer) const {
+        const InputType* input, OutputType* output) const {
-      const auto input = previous_layer_.Propagate(
-          transformed_features, buffer + kSelfBufferSize);
 
 #if defined (USE_AVX512)
-
+      using acc_vec_t = __m512i;
-      [[maybe_unused]] const __m512i kOnes512 = _mm512_set1_epi16(1);
+      using bias_vec_t = __m128i;
-
+      using weight_vec_t = __m512i;
-      [[maybe_unused]] auto m512_hadd = [](__m512i sum, int bias) -> int {
+      using in_vec_t = __m512i;
-        return _mm512_reduce_add_epi32(sum) + bias;
+      #define vec_zero _mm512_setzero_si512()
-      };
+      #define vec_add_dpbusd_32x2 Simd::m512_add_dpbusd_epi32x2
-
+      #define vec_hadd Simd::m512_hadd
-      [[maybe_unused]] auto m512_add_dpbusd_epi32 = [=](__m512i& acc, __m512i a, __m512i b) {
+      #define vec_haddx4 Simd::m512_haddx4
-#if defined (USE_VNNI)
-        acc = _mm512_dpbusd_epi32(acc, a, b);
-#else
-        __m512i product0 = _mm512_maddubs_epi16(a, b);
-        product0 = _mm512_madd_epi16(product0, kOnes512);
-        acc = _mm512_add_epi32(acc, product0);
-#endif
-      };
-
-      [[maybe_unused]] auto m512_add_dpbusd_epi32x4 = [=](__m512i& acc, __m512i a0, __m512i b0, __m512i a1, __m512i b1,
-                                                                        __m512i a2, __m512i b2, __m512i a3, __m512i b3) {
-#if defined (USE_VNNI)
-        acc = _mm512_dpbusd_epi32(acc, a0, b0);
-        acc = _mm512_dpbusd_epi32(acc, a1, b1);
-        acc = _mm512_dpbusd_epi32(acc, a2, b2);
-        acc = _mm512_dpbusd_epi32(acc, a3, b3);
-#else
-        __m512i product0 = _mm512_maddubs_epi16(a0, b0);
-        __m512i product1 = _mm512_maddubs_epi16(a1, b1);
-        __m512i product2 = _mm512_maddubs_epi16(a2, b2);
-        __m512i product3 = _mm512_maddubs_epi16(a3, b3);
-        product0 = _mm512_add_epi16(product0, product1);
-        product2 = _mm512_add_epi16(product2, product3);
-        product0 = _mm512_add_epi16(product0, product2);
-        product0 = _mm512_madd_epi16(product0, kOnes512);
-        acc = _mm512_add_epi32(acc, product0);
-#endif
-      };
-
-#endif
-#if defined (USE_AVX2)
-
-      [[maybe_unused]] const __m256i kOnes256 = _mm256_set1_epi16(1);
-
-      [[maybe_unused]] auto m256_hadd = [](__m256i sum, int bias) -> int {
-        __m128i sum128 = _mm_add_epi32(_mm256_castsi256_si128(sum), _mm256_extracti128_si256(sum, 1));
-        sum128 = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_BADC));
-        sum128 = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_CDAB));
-        return _mm_cvtsi128_si32(sum128) + bias;
-      };
-
-      [[maybe_unused]] auto m256_add_dpbusd_epi32 = [=](__m256i& acc, __m256i a, __m256i b) {
-#if defined (USE_VNNI)
-        acc = _mm256_dpbusd_epi32(acc, a, b);
-#else
-        __m256i product0 = _mm256_maddubs_epi16(a, b);
-        product0 = _mm256_madd_epi16(product0, kOnes256);
-        acc = _mm256_add_epi32(acc, product0);
-#endif
-      };
-
-      [[maybe_unused]] auto m256_add_dpbusd_epi32x4 = [=](__m256i& acc, __m256i a0, __m256i b0, __m256i a1, __m256i b1,
-                                                                        __m256i a2, __m256i b2, __m256i a3, __m256i b3) {
-#if defined (USE_VNNI)
-        acc = _mm256_dpbusd_epi32(acc, a0, b0);
-        acc = _mm256_dpbusd_epi32(acc, a1, b1);
-        acc = _mm256_dpbusd_epi32(acc, a2, b2);
-        acc = _mm256_dpbusd_epi32(acc, a3, b3);
-#else
-        __m256i product0 = _mm256_maddubs_epi16(a0, b0);
-        __m256i product1 = _mm256_maddubs_epi16(a1, b1);
-        __m256i product2 = _mm256_maddubs_epi16(a2, b2);
-        __m256i product3 = _mm256_maddubs_epi16(a3, b3);
-        product0 = _mm256_add_epi16(product0, product1);
-        product2 = _mm256_add_epi16(product2, product3);
-        product0 = _mm256_add_epi16(product0, product2);
-        product0 = _mm256_madd_epi16(product0, kOnes256);
-        acc = _mm256_add_epi32(acc, product0);
-#endif
-      };
-
-#endif
-#if defined (USE_SSSE3)
-
-      [[maybe_unused]] const __m128i kOnes128 = _mm_set1_epi16(1);
-
-      [[maybe_unused]] auto m128_hadd = [](__m128i sum, int bias) -> int {
-        sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0x4E)); //_MM_PERM_BADC
-        sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0xB1)); //_MM_PERM_CDAB
-        return _mm_cvtsi128_si32(sum) + bias;
-      };
-
-      [[maybe_unused]] auto m128_add_dpbusd_epi32 = [=](__m128i& acc, __m128i a, __m128i b) {
-        __m128i product0 = _mm_maddubs_epi16(a, b);
-        product0 = _mm_madd_epi16(product0, kOnes128);
-        acc = _mm_add_epi32(acc, product0);
-      };
-
-      [[maybe_unused]] auto m128_add_dpbusd_epi32x4 = [=](__m128i& acc, __m128i a0, __m128i b0, __m128i a1, __m128i b1,
-                                                                        __m128i a2, __m128i b2, __m128i a3, __m128i b3) {
-        __m128i product0 = _mm_maddubs_epi16(a0, b0);
-        __m128i product1 = _mm_maddubs_epi16(a1, b1);
-        __m128i product2 = _mm_maddubs_epi16(a2, b2);
-        __m128i product3 = _mm_maddubs_epi16(a3, b3);
-        product0 = _mm_adds_epi16(product0, product1);
-        product2 = _mm_adds_epi16(product2, product3);
-        product0 = _mm_adds_epi16(product0, product2);
-        product0 = _mm_madd_epi16(product0, kOnes128);
-        acc = _mm_add_epi32(acc, product0);
-      };
-
-#endif
-
-#if defined (USE_AVX512)
-      using vec_t = __m512i;
-      #define vec_setzero _mm512_setzero_si512
-      #define vec_set_32 _mm512_set1_epi32
-      auto& vec_add_dpbusd_32 = m512_add_dpbusd_epi32;
-      auto& vec_add_dpbusd_32x4 = m512_add_dpbusd_epi32x4;
-      auto& vec_hadd = m512_hadd;
 #elif defined (USE_AVX2)
-      using vec_t = __m256i;
+      using acc_vec_t = __m256i;
-      #define vec_setzero _mm256_setzero_si256
+      using bias_vec_t = __m128i;
-      #define vec_set_32 _mm256_set1_epi32
+      using weight_vec_t = __m256i;
-      auto& vec_add_dpbusd_32 = m256_add_dpbusd_epi32;
+      using in_vec_t = __m256i;
-      auto& vec_add_dpbusd_32x4 = m256_add_dpbusd_epi32x4;
+      #define vec_zero _mm256_setzero_si256()
-      auto& vec_hadd = m256_hadd;
+      #define vec_add_dpbusd_32x2 Simd::m256_add_dpbusd_epi32x2
+      #define vec_hadd Simd::m256_hadd
+      #define vec_haddx4 Simd::m256_haddx4
 #elif defined (USE_SSSE3)
-      using vec_t = __m128i;
+      using acc_vec_t = __m128i;
-      #define vec_setzero _mm_setzero_si128
+      using bias_vec_t = __m128i;
-      #define vec_set_32 _mm_set1_epi32
+      using weight_vec_t = __m128i;
-      auto& vec_add_dpbusd_32 = m128_add_dpbusd_epi32;
+      using in_vec_t = __m128i;
-      auto& vec_add_dpbusd_32x4 = m128_add_dpbusd_epi32x4;
+      #define vec_zero _mm_setzero_si128()
-      auto& vec_hadd = m128_hadd;
+      #define vec_add_dpbusd_32x2 Simd::m128_add_dpbusd_epi32x2
+      #define vec_hadd Simd::m128_hadd
+      #define vec_haddx4 Simd::m128_haddx4
+#elif defined (USE_NEON)
+      using acc_vec_t = int32x4_t;
+      using bias_vec_t = int32x4_t;
+      using weight_vec_t = int8x8_t;
+      using in_vec_t = int8x8_t;
+      #define vec_zero {0}
+      #define vec_add_dpbusd_32x2 Simd::neon_m128_add_dpbusd_epi32x2
+      #define vec_hadd Simd::neon_m128_hadd
+      #define vec_haddx4 Simd::neon_m128_haddx4
 #endif
 
-#if defined (USE_SSSE3)
+#if defined (USE_SSSE3) || defined (USE_NEON)
+      const in_vec_t* invec = reinterpret_cast<const in_vec_t*>(input);
 
-      const auto output = reinterpret_cast<OutputType*>(buffer);
+      // Perform accumulation to registers for each big block
-      const auto input_vector = reinterpret_cast<const vec_t*>(input);
+      for (IndexType bigBlock = 0; bigBlock < NumBigBlocks; ++bigBlock)
-
-      static_assert(kOutputDimensions % kOutputSimdWidth == 0 || kOutputDimensions == 1);
-
-      // kOutputDimensions is either 1 or a multiple of kSimdWidth
-      // because then it is also an input dimension.
-      if constexpr (kOutputDimensions % kOutputSimdWidth == 0)
       {
-          constexpr IndexType kNumChunks = kPaddedInputDimensions / 4;
+        acc_vec_t acc[NumOutputRegs] = { vec_zero };
 
-          const auto input32 = reinterpret_cast<const std::int32_t*>(input);
+        // Each big block has NumOutputRegs small blocks in each "row", one per register.
-          vec_t* outptr = reinterpret_cast<vec_t*>(output);
+        // We process two small blocks at a time to save on one addition without VNNI.
-          std::memcpy(output, biases_, kOutputDimensions * sizeof(OutputType));
+        for (IndexType smallBlock = 0; smallBlock < NumSmallBlocksPerOutput; smallBlock += 2)
+        {
+          const weight_vec_t* weightvec =
+            reinterpret_cast<const weight_vec_t*>(
+                weights
+              + bigBlock * BigBlockSize
+              + smallBlock * SmallBlockSize * NumOutputRegs);
 
-          for (int i = 0; i < (int)kNumChunks - 3; i += 4)
+          const in_vec_t in0 = invec[smallBlock + 0];
+          const in_vec_t in1 = invec[smallBlock + 1];
+
+          for (IndexType k = 0; k < NumOutputRegs; ++k)
+            vec_add_dpbusd_32x2(acc[k], in0, weightvec[k], in1, weightvec[k + NumOutputRegs]);
+        }
+
+        // Horizontally add all accumulators.
+        if constexpr (NumOutputRegs % 4 == 0)
+        {
+          bias_vec_t* outputvec = reinterpret_cast<bias_vec_t*>(output);
+          const bias_vec_t* biasvec = reinterpret_cast<const bias_vec_t*>(biases);
+
+          for (IndexType k = 0; k < NumOutputRegs; k += 4)
           {
-              const vec_t in0 = vec_set_32(input32[i + 0]);
+            const IndexType idx = (bigBlock * NumOutputRegs + k) / 4;
-              const vec_t in1 = vec_set_32(input32[i + 1]);
+            outputvec[idx] = vec_haddx4(acc[k+0], acc[k+1], acc[k+2], acc[k+3], biasvec[idx]);
-              const vec_t in2 = vec_set_32(input32[i + 2]);
-              const vec_t in3 = vec_set_32(input32[i + 3]);
-              const auto col0 = reinterpret_cast<const vec_t*>(&weights_[(i + 0) * kOutputDimensions * 4]);
-              const auto col1 = reinterpret_cast<const vec_t*>(&weights_[(i + 1) * kOutputDimensions * 4]);
-              const auto col2 = reinterpret_cast<const vec_t*>(&weights_[(i + 2) * kOutputDimensions * 4]);
-              const auto col3 = reinterpret_cast<const vec_t*>(&weights_[(i + 3) * kOutputDimensions * 4]);
-              for (int j = 0; j * kOutputSimdWidth < kOutputDimensions; ++j)
-                  vec_add_dpbusd_32x4(outptr[j], in0, col0[j], in1, col1[j], in2, col2[j], in3, col3[j]);
           }
-          for (int i = 0; i < canSaturate16.count; ++i)
+        }
-              output[canSaturate16.ids[i].out] += input[canSaturate16.ids[i].in] * canSaturate16.ids[i].w;
+        else
-      }
+        {
-      else if constexpr (kOutputDimensions == 1)
+          for (IndexType k = 0; k < NumOutputRegs; ++k)
-      {
-#if defined (USE_AVX512)
-          if constexpr (kPaddedInputDimensions % (kSimdWidth * 2) != 0)
           {
-              constexpr IndexType kNumChunks = kPaddedInputDimensions / kSimdWidth;
+            const IndexType idx = (bigBlock * NumOutputRegs + k);
-              const auto input_vector256 = reinterpret_cast<const __m256i*>(input);
+            output[idx] = vec_hadd(acc[k], biases[idx]);
-
-              __m256i sum0 = _mm256_setzero_si256();
-              const auto row0 = reinterpret_cast<const __m256i*>(&weights_[0]);
-
-              for (int j = 0; j < (int)kNumChunks; ++j)
-              {
-                  const __m256i in = input_vector256[j];
-                  m256_add_dpbusd_epi32(sum0, in, row0[j]);
-              }
-              output[0] = m256_hadd(sum0, biases_[0]);
-          }
-          else
-#endif
-          {
-#if defined (USE_AVX512)
-              constexpr IndexType kNumChunks = kPaddedInputDimensions / (kSimdWidth * 2);
-#else
-              constexpr IndexType kNumChunks = kPaddedInputDimensions / kSimdWidth;
-#endif
-              vec_t sum0 = vec_setzero();
-              const auto row0 = reinterpret_cast<const vec_t*>(&weights_[0]);
-
-              for (int j = 0; j < (int)kNumChunks; ++j)
-              {
-                  const vec_t in = input_vector[j];
-                  vec_add_dpbusd_32(sum0, in, row0[j]);
-              }
-              output[0] = vec_hadd(sum0, biases_[0]);
           }
+        }
       }
 
+# undef vec_zero
+# undef vec_add_dpbusd_32x2
+# undef vec_hadd
+# undef vec_haddx4
 #else
-
+      // Use old implementation for the other architectures.
-// Use old implementation for the other architectures.
+      affine_transform_non_ssse3<
-
+        InputDimensions,
-      auto output = reinterpret_cast<OutputType*>(buffer);
+        PaddedInputDimensions,
-
+        OutputDimensions>(output, weights, biases, input);
-#if defined(USE_SSE2)
-      constexpr IndexType kNumChunks = kPaddedInputDimensions / kSimdWidth;
-      const __m128i kZeros = _mm_setzero_si128();
-      const auto input_vector = reinterpret_cast<const __m128i*>(input);
-
-#elif defined(USE_MMX)
-      constexpr IndexType kNumChunks = kPaddedInputDimensions / kSimdWidth;
-      const __m64 kZeros = _mm_setzero_si64();
-      const auto input_vector = reinterpret_cast<const __m64*>(input);
-
-#elif defined(USE_NEON)
-      constexpr IndexType kNumChunks = kPaddedInputDimensions / kSimdWidth;
-      const auto input_vector = reinterpret_cast<const int8x8_t*>(input);
-#endif
-
-      for (IndexType i = 0; i < kOutputDimensions; ++i) {
-        const IndexType offset = i * kPaddedInputDimensions;
-
-#if defined(USE_SSE2)
-        __m128i sum_lo = _mm_cvtsi32_si128(biases_[i]);
-        __m128i sum_hi = kZeros;
-        const auto row = reinterpret_cast<const __m128i*>(&weights_[offset]);
-        for (IndexType j = 0; j < kNumChunks; ++j) {
-          __m128i row_j = _mm_load_si128(&row[j]);
-          __m128i input_j = _mm_load_si128(&input_vector[j]);
-          __m128i extended_row_lo = _mm_srai_epi16(_mm_unpacklo_epi8(row_j, row_j), 8);
-          __m128i extended_row_hi = _mm_srai_epi16(_mm_unpackhi_epi8(row_j, row_j), 8);
-          __m128i extended_input_lo = _mm_unpacklo_epi8(input_j, kZeros);
-          __m128i extended_input_hi = _mm_unpackhi_epi8(input_j, kZeros);
-          __m128i product_lo = _mm_madd_epi16(extended_row_lo, extended_input_lo);
-          __m128i product_hi = _mm_madd_epi16(extended_row_hi, extended_input_hi);
-          sum_lo = _mm_add_epi32(sum_lo, product_lo);
-          sum_hi = _mm_add_epi32(sum_hi, product_hi);
-        }
-        __m128i sum = _mm_add_epi32(sum_lo, sum_hi);
-        __m128i sum_high_64 = _mm_shuffle_epi32(sum, _MM_SHUFFLE(1, 0, 3, 2));
-        sum = _mm_add_epi32(sum, sum_high_64);
-        __m128i sum_second_32 = _mm_shufflelo_epi16(sum, _MM_SHUFFLE(1, 0, 3, 2));
-        sum = _mm_add_epi32(sum, sum_second_32);
-        output[i] = _mm_cvtsi128_si32(sum);
-
-#elif defined(USE_MMX)
-        __m64 sum_lo = _mm_cvtsi32_si64(biases_[i]);
-        __m64 sum_hi = kZeros;
-        const auto row = reinterpret_cast<const __m64*>(&weights_[offset]);
-        for (IndexType j = 0; j < kNumChunks; ++j) {
-          __m64 row_j = row[j];
-          __m64 input_j = input_vector[j];
-          __m64 extended_row_lo = _mm_srai_pi16(_mm_unpacklo_pi8(row_j, row_j), 8);
-          __m64 extended_row_hi = _mm_srai_pi16(_mm_unpackhi_pi8(row_j, row_j), 8);
-          __m64 extended_input_lo = _mm_unpacklo_pi8(input_j, kZeros);
-          __m64 extended_input_hi = _mm_unpackhi_pi8(input_j, kZeros);
-          __m64 product_lo = _mm_madd_pi16(extended_row_lo, extended_input_lo);
-          __m64 product_hi = _mm_madd_pi16(extended_row_hi, extended_input_hi);
-          sum_lo = _mm_add_pi32(sum_lo, product_lo);
-          sum_hi = _mm_add_pi32(sum_hi, product_hi);
-        }
-        __m64 sum = _mm_add_pi32(sum_lo, sum_hi);
-        sum = _mm_add_pi32(sum, _mm_unpackhi_pi32(sum, sum));
-        output[i] = _mm_cvtsi64_si32(sum);
-
-#elif defined(USE_NEON)
-        int32x4_t sum = {biases_[i]};
-        const auto row = reinterpret_cast<const int8x8_t*>(&weights_[offset]);
-        for (IndexType j = 0; j < kNumChunks; ++j) {
-          int16x8_t product = vmull_s8(input_vector[j * 2], row[j * 2]);
-          product = vmlal_s8(product, input_vector[j * 2 + 1], row[j * 2 + 1]);
-          sum = vpadalq_s16(sum, product);
-        }
-        output[i] = sum[0] + sum[1] + sum[2] + sum[3];
-
-#else
-        OutputType sum = biases_[i];
-        for (IndexType j = 0; j < kInputDimensions; ++j) {
-          sum += weights_[offset + j] * input[j];
-        }
-        output[i] = sum;
-#endif
-
-      }
-#if defined(USE_MMX)
-      _mm_empty();
-#endif
 
 #endif
 
@@ -436,29 +364,176 @@ namespace Eval::NNUE::Layers {
     using BiasType = OutputType;
     using WeightType = std::int8_t;
 
-    PreviousLayer previous_layer_;
+    alignas(CacheLineSize) BiasType biases[OutputDimensions];
-
+    alignas(CacheLineSize) WeightType weights[OutputDimensions * PaddedInputDimensions];
-    alignas(kCacheLineSize) BiasType biases_[kOutputDimensions];
-    alignas(kCacheLineSize) WeightType weights_[kOutputDimensions * kPaddedInputDimensions];
-#if defined (USE_SSSE3)
-    struct CanSaturate {
-        int count;
-        struct Entry {
-            uint16_t out;
-            uint16_t in;
-            int8_t w;
-        } ids[kPaddedInputDimensions * kOutputDimensions * 3 / 4];
-
-        void add(int i, int j, int8_t w) {
-            ids[count].out = i;
-            ids[count].in = j;
-            ids[count].w = w;
-            ++count;
-        }
-    } canSaturate16;
-#endif
   };
 
-}  // namespace Eval::NNUE::Layers
+  template <IndexType InDims, IndexType OutDims>
+  class AffineTransform<InDims, OutDims, std::enable_if_t<(ceil_to_multiple<IndexType>(InDims, MaxSimdWidth) < 2*64)>> {
+   public:
+    // Input/output type
+    // Input/output type
+    using InputType = std::uint8_t;
+    using OutputType = std::int32_t;
+
+    // Number of input/output dimensions
+    static constexpr IndexType InputDimensions = InDims;
+    static constexpr IndexType OutputDimensions = OutDims;
+
+    static constexpr IndexType PaddedInputDimensions =
+      ceil_to_multiple<IndexType>(InputDimensions, MaxSimdWidth);
+    static constexpr IndexType PaddedOutputDimensions =
+      ceil_to_multiple<IndexType>(OutputDimensions, MaxSimdWidth);
+
+    using OutputBuffer = OutputType[PaddedOutputDimensions];
+
+    static_assert(PaddedInputDimensions < 128, "Something went wrong. This specialization should not have been chosen.");
+
+#if defined (USE_SSSE3)
+    static constexpr const IndexType OutputSimdWidth = SimdWidth / 4;
+    static constexpr const IndexType InputSimdWidth = SimdWidth;
+#endif
+
+    // Hash value embedded in the evaluation file
+    static constexpr std::uint32_t get_hash_value(std::uint32_t prevHash) {
+      std::uint32_t hashValue = 0xCC03DAE4u;
+      hashValue += OutputDimensions;
+      hashValue ^= prevHash >> 1;
+      hashValue ^= prevHash << 31;
+      return hashValue;
+    }
+
+    static IndexType get_weight_index_scrambled(IndexType i)
+    {
+      return
+        (i / 4) % (PaddedInputDimensions / 4) * OutputDimensions * 4 +
+        i / PaddedInputDimensions * 4 +
+        i % 4;
+    }
+
+    static IndexType get_weight_index(IndexType i)
+    {
+#if defined (USE_SSSE3)
+      return get_weight_index_scrambled(i);
+#else
+      return i;
+#endif
+    }
+
+    // Read network parameters
+    bool read_parameters(std::istream& stream) {
+      for (std::size_t i = 0; i < OutputDimensions; ++i)
+        biases[i] = read_little_endian<BiasType>(stream);
+      for (std::size_t i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
+        weights[get_weight_index(i)] = read_little_endian<WeightType>(stream);
+
+      return !stream.fail();
+    }
+
+    // Write network parameters
+    bool write_parameters(std::ostream& stream) const {
+      for (std::size_t i = 0; i < OutputDimensions; ++i)
+        write_little_endian<BiasType>(stream, biases[i]);
+
+      for (std::size_t i = 0; i < OutputDimensions * PaddedInputDimensions; ++i)
+        write_little_endian<WeightType>(stream, weights[get_weight_index(i)]);
+
+      return !stream.fail();
+    }
+    // Forward propagation
+    const OutputType* propagate(
+        const InputType* input, OutputType* output) const {
+
+#if defined (USE_AVX2)
+      using vec_t = __m256i;
+      #define vec_setzero _mm256_setzero_si256
+      #define vec_set_32 _mm256_set1_epi32
+      #define vec_add_dpbusd_32 Simd::m256_add_dpbusd_epi32
+      #define vec_add_dpbusd_32x2 Simd::m256_add_dpbusd_epi32x2
+      #define vec_add_dpbusd_32x4 Simd::m256_add_dpbusd_epi32x4
+      #define vec_hadd Simd::m256_hadd
+      #define vec_haddx4 Simd::m256_haddx4
+#elif defined (USE_SSSE3)
+      using vec_t = __m128i;
+      #define vec_setzero _mm_setzero_si128
+      #define vec_set_32 _mm_set1_epi32
+      #define vec_add_dpbusd_32 Simd::m128_add_dpbusd_epi32
+      #define vec_add_dpbusd_32x2 Simd::m128_add_dpbusd_epi32x2
+      #define vec_add_dpbusd_32x4 Simd::m128_add_dpbusd_epi32x4
+      #define vec_hadd Simd::m128_hadd
+      #define vec_haddx4 Simd::m128_haddx4
+#endif
+
+#if defined (USE_SSSE3)
+      const auto inputVector = reinterpret_cast<const vec_t*>(input);
+
+      static_assert(OutputDimensions % OutputSimdWidth == 0 || OutputDimensions == 1);
+
+      if constexpr (OutputDimensions % OutputSimdWidth == 0)
+      {
+        constexpr IndexType NumChunks = ceil_to_multiple<IndexType>(InputDimensions, 8) / 4;
+        constexpr IndexType NumRegs = OutputDimensions / OutputSimdWidth;
+
+        const auto input32 = reinterpret_cast<const std::int32_t*>(input);
+        const vec_t* biasvec = reinterpret_cast<const vec_t*>(biases);
+        vec_t acc[NumRegs];
+        for (IndexType k = 0; k < NumRegs; ++k)
+          acc[k] = biasvec[k];
+
+        for (IndexType i = 0; i < NumChunks; i += 2)
+        {
+          const vec_t in0 = vec_set_32(input32[i + 0]);
+          const vec_t in1 = vec_set_32(input32[i + 1]);
+          const auto col0 = reinterpret_cast<const vec_t*>(&weights[(i + 0) * OutputDimensions * 4]);
+          const auto col1 = reinterpret_cast<const vec_t*>(&weights[(i + 1) * OutputDimensions * 4]);
+          for (IndexType k = 0; k < NumRegs; ++k)
+            vec_add_dpbusd_32x2(acc[k], in0, col0[k], in1, col1[k]);
+        }
+
+        vec_t* outptr = reinterpret_cast<vec_t*>(output);
+        for (IndexType k = 0; k < NumRegs; ++k)
+          outptr[k] = acc[k];
+      }
+      else if constexpr (OutputDimensions == 1)
+      {
+        constexpr IndexType NumChunks = PaddedInputDimensions / SimdWidth;
+        vec_t sum0 = vec_setzero();
+        const auto row0 = reinterpret_cast<const vec_t*>(&weights[0]);
+
+        for (int j = 0; j < (int)NumChunks; ++j)
+        {
+          const vec_t in = inputVector[j];
+          vec_add_dpbusd_32(sum0, in, row0[j]);
+        }
+        output[0] = vec_hadd(sum0, biases[0]);
+      }
+
+# undef vec_setzero
+# undef vec_set_32
+# undef vec_add_dpbusd_32
+# undef vec_add_dpbusd_32x2
+# undef vec_add_dpbusd_32x4
+# undef vec_hadd
+# undef vec_haddx4
+#else
+      // Use old implementation for the other architectures.
+      affine_transform_non_ssse3<
+        InputDimensions,
+        PaddedInputDimensions,
+        OutputDimensions>(output, weights, biases, input);
+#endif
+
+      return output;
+    }
+
+   private:
+    using BiasType = OutputType;
+    using WeightType = std::int8_t;
+
+    alignas(CacheLineSize) BiasType biases[OutputDimensions];
+    alignas(CacheLineSize) WeightType weights[OutputDimensions * PaddedInputDimensions];
+  };
+
+}  // namespace Stockfish::Eval::NNUE::Layers
 
 #endif // #ifndef NNUE_LAYERS_AFFINE_TRANSFORM_H_INCLUDED

src/nnue/layers/clipped_relu.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -23,144 +23,166 @@
 
 #include "../nnue_common.h"
 
-namespace Eval::NNUE::Layers {
+namespace Stockfish::Eval::NNUE::Layers {
 
   // Clipped ReLU
-  template <typename PreviousLayer>
+  template <IndexType InDims>
   class ClippedReLU {
    public:
     // Input/output type
-    using InputType = typename PreviousLayer::OutputType;
+    using InputType = std::int32_t;
     using OutputType = std::uint8_t;
-    static_assert(std::is_same<InputType, std::int32_t>::value, "");
 
     // Number of input/output dimensions
-    static constexpr IndexType kInputDimensions =
+    static constexpr IndexType InputDimensions = InDims;
-        PreviousLayer::kOutputDimensions;
+    static constexpr IndexType OutputDimensions = InputDimensions;
-    static constexpr IndexType kOutputDimensions = kInputDimensions;
+    static constexpr IndexType PaddedOutputDimensions =
+        ceil_to_multiple<IndexType>(OutputDimensions, 32);
 
-    // Size of forward propagation buffer used in this layer
+    using OutputBuffer = OutputType[PaddedOutputDimensions];
-    static constexpr std::size_t kSelfBufferSize =
-        CeilToMultiple(kOutputDimensions * sizeof(OutputType), kCacheLineSize);
-
-    // Size of the forward propagation buffer used from the input layer to this layer
-    static constexpr std::size_t kBufferSize =
-        PreviousLayer::kBufferSize + kSelfBufferSize;
 
     // Hash value embedded in the evaluation file
-    static constexpr std::uint32_t GetHashValue() {
+    static constexpr std::uint32_t get_hash_value(std::uint32_t prevHash) {
-      std::uint32_t hash_value = 0x538D24C7u;
+      std::uint32_t hashValue = 0x538D24C7u;
-      hash_value += PreviousLayer::GetHashValue();
+      hashValue += prevHash;
-      return hash_value;
+      return hashValue;
     }
 
     // Read network parameters
-    bool ReadParameters(std::istream& stream) {
+    bool read_parameters(std::istream&) {
-      return previous_layer_.ReadParameters(stream);
+      return true;
+    }
+
+    // Write network parameters
+    bool write_parameters(std::ostream&) const {
+      return true;
     }
 
     // Forward propagation
-    const OutputType* Propagate(
+    const OutputType* propagate(
-        const TransformedFeatureType* transformed_features, char* buffer) const {
+        const InputType* input, OutputType* output) const {
-      const auto input = previous_layer_.Propagate(
-          transformed_features, buffer + kSelfBufferSize);
-      const auto output = reinterpret_cast<OutputType*>(buffer);
 
   #if defined(USE_AVX2)
-      constexpr IndexType kNumChunks = kInputDimensions / kSimdWidth;
+      if constexpr (InputDimensions % SimdWidth == 0) {
-      const __m256i kZero = _mm256_setzero_si256();
+        constexpr IndexType NumChunks = InputDimensions / SimdWidth;
-      const __m256i kOffsets = _mm256_set_epi32(7, 3, 6, 2, 5, 1, 4, 0);
+        const __m256i Zero = _mm256_setzero_si256();
-      const auto in = reinterpret_cast<const __m256i*>(input);
+        const __m256i Offsets = _mm256_set_epi32(7, 3, 6, 2, 5, 1, 4, 0);
-      const auto out = reinterpret_cast<__m256i*>(output);
+        const auto in = reinterpret_cast<const __m256i*>(input);
-      for (IndexType i = 0; i < kNumChunks; ++i) {
+        const auto out = reinterpret_cast<__m256i*>(output);
-        const __m256i words0 = _mm256_srai_epi16(_mm256_packs_epi32(
+        for (IndexType i = 0; i < NumChunks; ++i) {
-            _mm256_load_si256(&in[i * 4 + 0]),
+          const __m256i words0 = _mm256_srai_epi16(_mm256_packs_epi32(
-            _mm256_load_si256(&in[i * 4 + 1])), kWeightScaleBits);
+              _mm256_load_si256(&in[i * 4 + 0]),
-        const __m256i words1 = _mm256_srai_epi16(_mm256_packs_epi32(
+              _mm256_load_si256(&in[i * 4 + 1])), WeightScaleBits);
-            _mm256_load_si256(&in[i * 4 + 2]),
+          const __m256i words1 = _mm256_srai_epi16(_mm256_packs_epi32(
-            _mm256_load_si256(&in[i * 4 + 3])), kWeightScaleBits);
+              _mm256_load_si256(&in[i * 4 + 2]),
-        _mm256_store_si256(&out[i], _mm256_permutevar8x32_epi32(_mm256_max_epi8(
+              _mm256_load_si256(&in[i * 4 + 3])), WeightScaleBits);
-            _mm256_packs_epi16(words0, words1), kZero), kOffsets));
+          _mm256_store_si256(&out[i], _mm256_permutevar8x32_epi32(_mm256_max_epi8(
+              _mm256_packs_epi16(words0, words1), Zero), Offsets));
+        }
+      } else {
+        constexpr IndexType NumChunks = InputDimensions / (SimdWidth / 2);
+        const __m128i Zero = _mm_setzero_si128();
+        const auto in = reinterpret_cast<const __m128i*>(input);
+        const auto out = reinterpret_cast<__m128i*>(output);
+        for (IndexType i = 0; i < NumChunks; ++i) {
+          const __m128i words0 = _mm_srai_epi16(_mm_packs_epi32(
+              _mm_load_si128(&in[i * 4 + 0]),
+              _mm_load_si128(&in[i * 4 + 1])), WeightScaleBits);
+          const __m128i words1 = _mm_srai_epi16(_mm_packs_epi32(
+              _mm_load_si128(&in[i * 4 + 2]),
+              _mm_load_si128(&in[i * 4 + 3])), WeightScaleBits);
+          const __m128i packedbytes = _mm_packs_epi16(words0, words1);
+          _mm_store_si128(&out[i], _mm_max_epi8(packedbytes, Zero));
+        }
       }
-      constexpr IndexType kStart = kNumChunks * kSimdWidth;
+      constexpr IndexType Start =
+        InputDimensions % SimdWidth == 0
+        ? InputDimensions / SimdWidth * SimdWidth
+        : InputDimensions / (SimdWidth / 2) * (SimdWidth / 2);
 
   #elif defined(USE_SSE2)
-      constexpr IndexType kNumChunks = kInputDimensions / kSimdWidth;
+      constexpr IndexType NumChunks = InputDimensions / SimdWidth;
 
   #ifdef USE_SSE41
-      const __m128i kZero = _mm_setzero_si128();
+      const __m128i Zero = _mm_setzero_si128();
   #else
       const __m128i k0x80s = _mm_set1_epi8(-128);
   #endif
 
       const auto in = reinterpret_cast<const __m128i*>(input);
       const auto out = reinterpret_cast<__m128i*>(output);
-      for (IndexType i = 0; i < kNumChunks; ++i) {
+      for (IndexType i = 0; i < NumChunks; ++i) {
         const __m128i words0 = _mm_srai_epi16(_mm_packs_epi32(
             _mm_load_si128(&in[i * 4 + 0]),
-            _mm_load_si128(&in[i * 4 + 1])), kWeightScaleBits);
+            _mm_load_si128(&in[i * 4 + 1])), WeightScaleBits);
         const __m128i words1 = _mm_srai_epi16(_mm_packs_epi32(
             _mm_load_si128(&in[i * 4 + 2]),
-            _mm_load_si128(&in[i * 4 + 3])), kWeightScaleBits);
+            _mm_load_si128(&in[i * 4 + 3])), WeightScaleBits);
         const __m128i packedbytes = _mm_packs_epi16(words0, words1);
         _mm_store_si128(&out[i],
 
   #ifdef USE_SSE41
-          _mm_max_epi8(packedbytes, kZero)
+          _mm_max_epi8(packedbytes, Zero)
   #else
           _mm_subs_epi8(_mm_adds_epi8(packedbytes, k0x80s), k0x80s)
   #endif
 
         );
       }
-      constexpr IndexType kStart = kNumChunks * kSimdWidth;
+      constexpr IndexType Start = NumChunks * SimdWidth;
 
   #elif defined(USE_MMX)
-      constexpr IndexType kNumChunks = kInputDimensions / kSimdWidth;
+      constexpr IndexType NumChunks = InputDimensions / SimdWidth;
       const __m64 k0x80s = _mm_set1_pi8(-128);
       const auto in = reinterpret_cast<const __m64*>(input);
       const auto out = reinterpret_cast<__m64*>(output);
-      for (IndexType i = 0; i < kNumChunks; ++i) {
+      for (IndexType i = 0; i < NumChunks; ++i) {
         const __m64 words0 = _mm_srai_pi16(
             _mm_packs_pi32(in[i * 4 + 0], in[i * 4 + 1]),
-            kWeightScaleBits);
+            WeightScaleBits);
         const __m64 words1 = _mm_srai_pi16(
             _mm_packs_pi32(in[i * 4 + 2], in[i * 4 + 3]),
-            kWeightScaleBits);
+            WeightScaleBits);
         const __m64 packedbytes = _mm_packs_pi16(words0, words1);
         out[i] = _mm_subs_pi8(_mm_adds_pi8(packedbytes, k0x80s), k0x80s);
       }
       _mm_empty();
-      constexpr IndexType kStart = kNumChunks * kSimdWidth;
+      constexpr IndexType Start = NumChunks * SimdWidth;
 
   #elif defined(USE_NEON)
-      constexpr IndexType kNumChunks = kInputDimensions / (kSimdWidth / 2);
+      constexpr IndexType NumChunks = InputDimensions / (SimdWidth / 2);
-      const int8x8_t kZero = {0};
+      const int8x8_t Zero = {0};
       const auto in = reinterpret_cast<const int32x4_t*>(input);
       const auto out = reinterpret_cast<int8x8_t*>(output);
-      for (IndexType i = 0; i < kNumChunks; ++i) {
+      for (IndexType i = 0; i < NumChunks; ++i) {
         int16x8_t shifted;
         const auto pack = reinterpret_cast<int16x4_t*>(&shifted);
-        pack[0] = vqshrn_n_s32(in[i * 2 + 0], kWeightScaleBits);
+        pack[0] = vqshrn_n_s32(in[i * 2 + 0], WeightScaleBits);
-        pack[1] = vqshrn_n_s32(in[i * 2 + 1], kWeightScaleBits);
+        pack[1] = vqshrn_n_s32(in[i * 2 + 1], WeightScaleBits);
-        out[i] = vmax_s8(vqmovn_s16(shifted), kZero);
+        out[i] = vmax_s8(vqmovn_s16(shifted), Zero);
       }
-      constexpr IndexType kStart = kNumChunks * (kSimdWidth / 2);
+      constexpr IndexType Start = NumChunks * (SimdWidth / 2);
   #else
-      constexpr IndexType kStart = 0;
+      constexpr IndexType Start = 0;
   #endif
 
-      for (IndexType i = kStart; i < kInputDimensions; ++i) {
+      for (IndexType i = Start; i < InputDimensions; ++i) {
         output[i] = static_cast<OutputType>(
-            std::max(0, std::min(127, input[i] >> kWeightScaleBits)));
+            std::max(0, std::min(127, input[i] >> WeightScaleBits)));
       }
+
+      // Affine transform layers expect that there is at least
+      // ceil_to_multiple(OutputDimensions, 32) initialized values.
+      // We cannot do this in the affine transform because it requires
+      // preallocating space here.
+      for (IndexType i = OutputDimensions; i < PaddedOutputDimensions; ++i) {
+        output[i] = 0;
+      }
+
       return output;
     }
-
-   private:
-    PreviousLayer previous_layer_;
   };
 
-}  // namespace Eval::NNUE::Layers
+}  // namespace Stockfish::Eval::NNUE::Layers
 
 #endif // NNUE_LAYERS_CLIPPED_RELU_H_INCLUDED

src/nnue/layers/input_slice.h

@@ -1,68 +0,0 @@
-/*
-  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
-
-  Stockfish is free software: you can redistribute it and/or modify
-  it under the terms of the GNU General Public License as published by
-  the Free Software Foundation, either version 3 of the License, or
-  (at your option) any later version.
-
-  Stockfish is distributed in the hope that it will be useful,
-  but WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-  GNU General Public License for more details.
-
-  You should have received a copy of the GNU General Public License
-  along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-// NNUE evaluation function layer InputSlice definition
-
-#ifndef NNUE_LAYERS_INPUT_SLICE_H_INCLUDED
-#define NNUE_LAYERS_INPUT_SLICE_H_INCLUDED
-
-#include "../nnue_common.h"
-
-namespace Eval::NNUE::Layers {
-
-// Input layer
-template <IndexType OutputDimensions, IndexType Offset = 0>
-class InputSlice {
- public:
-  // Need to maintain alignment
-  static_assert(Offset % kMaxSimdWidth == 0, "");
-
-  // Output type
-  using OutputType = TransformedFeatureType;
-
-  // Output dimensionality
-  static constexpr IndexType kOutputDimensions = OutputDimensions;
-
-  // Size of forward propagation buffer used from the input layer to this layer
-  static constexpr std::size_t kBufferSize = 0;
-
-  // Hash value embedded in the evaluation file
-  static constexpr std::uint32_t GetHashValue() {
-    std::uint32_t hash_value = 0xEC42E90Du;
-    hash_value ^= kOutputDimensions ^ (Offset << 10);
-    return hash_value;
-  }
-
-  // Read network parameters
-  bool ReadParameters(std::istream& /*stream*/) {
-    return true;
-  }
-
-  // Forward propagation
-  const OutputType* Propagate(
-      const TransformedFeatureType* transformed_features,
-      char* /*buffer*/) const {
-    return transformed_features + Offset;
-  }
-
- private:
-};
-
-}  // namespace Layers
-
-#endif // #ifndef NNUE_LAYERS_INPUT_SLICE_H_INCLUDED

src/nnue/nnue_accumulator.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -23,18 +23,15 @@
 
 #include "nnue_architecture.h"
 
-namespace Eval::NNUE {
+namespace Stockfish::Eval::NNUE {
-
-  // The accumulator of a StateInfo without parent is set to the INIT state
-  enum AccumulatorState { EMPTY, COMPUTED, INIT };
 
   // Class that holds the result of affine transformation of input features
-  struct alignas(kCacheLineSize) Accumulator {
+  struct alignas(CacheLineSize) Accumulator {
-    std::int16_t
+    std::int16_t accumulation[2][TransformedFeatureDimensions];
-        accumulation[2][kRefreshTriggers.size()][kTransformedFeatureDimensions];
+    std::int32_t psqtAccumulation[2][PSQTBuckets];
-    AccumulatorState state[2];
+    bool computed[2];
   };
 
-}  // namespace Eval::NNUE
+}  // namespace Stockfish::Eval::NNUE
 
 #endif // NNUE_ACCUMULATOR_H_INCLUDED

src/nnue/nnue_architecture.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -21,18 +21,111 @@
 #ifndef NNUE_ARCHITECTURE_H_INCLUDED
 #define NNUE_ARCHITECTURE_H_INCLUDED
 
-// Defines the network structure
+#include "nnue_common.h"
-#include "architectures/halfkp_256x2-32-32.h"
 
-namespace Eval::NNUE {
+#include "features/half_ka_v2_hm.h"
 
-  static_assert(kTransformedFeatureDimensions % kMaxSimdWidth == 0, "");
+#include "layers/affine_transform.h"
-  static_assert(Network::kOutputDimensions == 1, "");
+#include "layers/clipped_relu.h"
-  static_assert(std::is_same<Network::OutputType, std::int32_t>::value, "");
 
-  // Trigger for full calculation instead of difference calculation
+#include "../misc.h"
-  constexpr auto kRefreshTriggers = RawFeatures::kRefreshTriggers;
 
-}  // namespace Eval::NNUE
+namespace Stockfish::Eval::NNUE {
+
+// Input features used in evaluation function
+using FeatureSet = Features::HalfKAv2_hm;
+
+// Number of input feature dimensions after conversion
+constexpr IndexType TransformedFeatureDimensions = 1024;
+constexpr IndexType PSQTBuckets = 8;
+constexpr IndexType LayerStacks = 8;
+
+struct Network
+{
+  static constexpr int FC_0_OUTPUTS = 15;
+  static constexpr int FC_1_OUTPUTS = 32;
+
+  Layers::AffineTransform<TransformedFeatureDimensions, FC_0_OUTPUTS + 1> fc_0;
+  Layers::ClippedReLU<FC_0_OUTPUTS> ac_0;
+  Layers::AffineTransform<FC_0_OUTPUTS, FC_1_OUTPUTS> fc_1;
+  Layers::ClippedReLU<FC_1_OUTPUTS> ac_1;
+  Layers::AffineTransform<FC_1_OUTPUTS, 1> fc_2;
+
+  // Hash value embedded in the evaluation file
+  static constexpr std::uint32_t get_hash_value() {
+    // input slice hash
+    std::uint32_t hashValue = 0xEC42E90Du;
+    hashValue ^= TransformedFeatureDimensions * 2;
+
+    hashValue = decltype(fc_0)::get_hash_value(hashValue);
+    hashValue = decltype(ac_0)::get_hash_value(hashValue);
+    hashValue = decltype(fc_1)::get_hash_value(hashValue);
+    hashValue = decltype(ac_1)::get_hash_value(hashValue);
+    hashValue = decltype(fc_2)::get_hash_value(hashValue);
+
+    return hashValue;
+  }
+
+  // Read network parameters
+  bool read_parameters(std::istream& stream) {
+    if (!fc_0.read_parameters(stream)) return false;
+    if (!ac_0.read_parameters(stream)) return false;
+    if (!fc_1.read_parameters(stream)) return false;
+    if (!ac_1.read_parameters(stream)) return false;
+    if (!fc_2.read_parameters(stream)) return false;
+    return true;
+  }
+
+  // Read network parameters
+  bool write_parameters(std::ostream& stream) const {
+    if (!fc_0.write_parameters(stream)) return false;
+    if (!ac_0.write_parameters(stream)) return false;
+    if (!fc_1.write_parameters(stream)) return false;
+    if (!ac_1.write_parameters(stream)) return false;
+    if (!fc_2.write_parameters(stream)) return false;
+    return true;
+  }
+
+  std::int32_t propagate(const TransformedFeatureType* transformedFeatures)
+  {
+    constexpr uint64_t alignment = CacheLineSize;
+
+    struct Buffer
+    {
+      alignas(CacheLineSize) decltype(fc_0)::OutputBuffer fc_0_out;
+      alignas(CacheLineSize) decltype(ac_0)::OutputBuffer ac_0_out;
+      alignas(CacheLineSize) decltype(fc_1)::OutputBuffer fc_1_out;
+      alignas(CacheLineSize) decltype(ac_1)::OutputBuffer ac_1_out;
+      alignas(CacheLineSize) decltype(fc_2)::OutputBuffer fc_2_out;
+    };
+
+#if defined(ALIGNAS_ON_STACK_VARIABLES_BROKEN)
+    char bufferRaw[sizeof(Buffer) + alignment];
+    char* bufferRawAligned = align_ptr_up<alignment>(&bufferRaw[0]);
+    Buffer& buffer = *(new (bufferRawAligned) Buffer);
+#else
+    alignas(alignment) Buffer buffer;
+#endif
+
+    fc_0.propagate(transformedFeatures, buffer.fc_0_out);
+    ac_0.propagate(buffer.fc_0_out, buffer.ac_0_out);
+    fc_1.propagate(buffer.ac_0_out, buffer.fc_1_out);
+    ac_1.propagate(buffer.fc_1_out, buffer.ac_1_out);
+    fc_2.propagate(buffer.ac_1_out, buffer.fc_2_out);
+
+    // buffer.fc_0_out[FC_0_OUTPUTS] is such that 1.0 is equal to 127*(1<<WeightScaleBits) in quantized form
+    // but we want 1.0 to be equal to 600*OutputScale
+    std::int32_t fwdOut = int(buffer.fc_0_out[FC_0_OUTPUTS]) * (600*OutputScale) / (127*(1<<WeightScaleBits));
+    std::int32_t outputValue = buffer.fc_2_out[0] + fwdOut;
+
+#if defined(ALIGNAS_ON_STACK_VARIABLES_BROKEN)
+    buffer.~Buffer();
+#endif
+
+    return outputValue;
+  }
+};
+
+}  // namespace Stockfish::Eval::NNUE
 
 #endif // #ifndef NNUE_ARCHITECTURE_H_INCLUDED

src/nnue/nnue_common.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -24,6 +24,8 @@
 #include <cstring>
 #include <iostream>
 
+#include "../misc.h"  // for IsLittleEndian
+
 #if defined(USE_AVX2)
 #include <immintrin.h>
 
@@ -43,61 +45,33 @@
 #include <arm_neon.h>
 #endif
 
-namespace Eval::NNUE {
+namespace Stockfish::Eval::NNUE {
 
   // Version of the evaluation file
-  constexpr std::uint32_t kVersion = 0x7AF32F16u;
+  constexpr std::uint32_t Version = 0x7AF32F20u;
 
   // Constant used in evaluation value calculation
-  constexpr int FV_SCALE = 16;
+  constexpr int OutputScale = 16;
-  constexpr int kWeightScaleBits = 6;
+  constexpr int WeightScaleBits = 6;
 
   // Size of cache line (in bytes)
-  constexpr std::size_t kCacheLineSize = 64;
+  constexpr std::size_t CacheLineSize = 64;
 
   // SIMD width (in bytes)
   #if defined(USE_AVX2)
-  constexpr std::size_t kSimdWidth = 32;
+  constexpr std::size_t SimdWidth = 32;
 
   #elif defined(USE_SSE2)
-  constexpr std::size_t kSimdWidth = 16;
+  constexpr std::size_t SimdWidth = 16;
 
   #elif defined(USE_MMX)
-  constexpr std::size_t kSimdWidth = 8;
+  constexpr std::size_t SimdWidth = 8;
 
   #elif defined(USE_NEON)
-  constexpr std::size_t kSimdWidth = 16;
+  constexpr std::size_t SimdWidth = 16;
   #endif
 
-  constexpr std::size_t kMaxSimdWidth = 32;
+  constexpr std::size_t MaxSimdWidth = 32;
-
-  // unique number for each piece type on each square
-  enum {
-    PS_NONE     =  0,
-    PS_W_PAWN   =  1,
-    PS_B_PAWN   =  1 * SQUARE_NB + 1,
-    PS_W_KNIGHT =  2 * SQUARE_NB + 1,
-    PS_B_KNIGHT =  3 * SQUARE_NB + 1,
-    PS_W_BISHOP =  4 * SQUARE_NB + 1,
-    PS_B_BISHOP =  5 * SQUARE_NB + 1,
-    PS_W_ROOK   =  6 * SQUARE_NB + 1,
-    PS_B_ROOK   =  7 * SQUARE_NB + 1,
-    PS_W_QUEEN  =  8 * SQUARE_NB + 1,
-    PS_B_QUEEN  =  9 * SQUARE_NB + 1,
-    PS_W_KING   = 10 * SQUARE_NB + 1,
-    PS_END      = PS_W_KING, // pieces without kings (pawns included)
-    PS_B_KING   = 11 * SQUARE_NB + 1,
-    PS_END2     = 12 * SQUARE_NB + 1
-  };
-
-  constexpr uint32_t kpp_board_index[COLOR_NB][PIECE_NB] = {
-    // convention: W - us, B - them
-    // viewed from other side, W and B are reversed
-    { PS_NONE, PS_W_PAWN, PS_W_KNIGHT, PS_W_BISHOP, PS_W_ROOK, PS_W_QUEEN, PS_W_KING, PS_NONE,
-      PS_NONE, PS_B_PAWN, PS_B_KNIGHT, PS_B_BISHOP, PS_B_ROOK, PS_B_QUEEN, PS_B_KING, PS_NONE },
-    { PS_NONE, PS_B_PAWN, PS_B_KNIGHT, PS_B_BISHOP, PS_B_ROOK, PS_B_QUEEN, PS_B_KING, PS_NONE,
-      PS_NONE, PS_W_PAWN, PS_W_KNIGHT, PS_W_BISHOP, PS_W_ROOK, PS_W_QUEEN, PS_W_KING, PS_NONE }
-  };
 
   // Type of input feature after conversion
   using TransformedFeatureType = std::uint8_t;
@@ -105,7 +79,7 @@ namespace Eval::NNUE {
 
   // Round n up to be a multiple of base
   template <typename IntType>
-  constexpr IntType CeilToMultiple(IntType n, IntType base) {
+  constexpr IntType ceil_to_multiple(IntType n, IntType base) {
       return (n + base - 1) / base * base;
   }
 
@@ -114,19 +88,77 @@ namespace Eval::NNUE {
   // necessary to return a result with the byte ordering of the compiling machine.
   template <typename IntType>
   inline IntType read_little_endian(std::istream& stream) {
-
       IntType result;
-      std::uint8_t u[sizeof(IntType)];
-      typename std::make_unsigned<IntType>::type v = 0;
 
-      stream.read(reinterpret_cast<char*>(u), sizeof(IntType));
+      if (IsLittleEndian)
-      for (std::size_t i = 0; i < sizeof(IntType); ++i)
+          stream.read(reinterpret_cast<char*>(&result), sizeof(IntType));
-          v = (v << 8) | u[sizeof(IntType) - i - 1];
+      else
+      {
+          std::uint8_t u[sizeof(IntType)];
+          typename std::make_unsigned<IntType>::type v = 0;
+
+          stream.read(reinterpret_cast<char*>(u), sizeof(IntType));
+          for (std::size_t i = 0; i < sizeof(IntType); ++i)
+              v = (v << 8) | u[sizeof(IntType) - i - 1];
+
+          std::memcpy(&result, &v, sizeof(IntType));
+      }
 
-      std::memcpy(&result, &v, sizeof(IntType));
       return result;
   }
 
-}  // namespace Eval::NNUE
+  // write_little_endian() is our utility to write an integer (signed or unsigned, any size)
+  // to a stream in little-endian order. We swap the byte order before the write if
+  // necessary to always write in little endian order, independently of the byte
+  // ordering of the compiling machine.
+  template <typename IntType>
+  inline void write_little_endian(std::ostream& stream, IntType value) {
+
+      if (IsLittleEndian)
+          stream.write(reinterpret_cast<const char*>(&value), sizeof(IntType));
+      else
+      {
+          std::uint8_t u[sizeof(IntType)];
+          typename std::make_unsigned<IntType>::type v = value;
+
+          std::size_t i = 0;
+          // if constexpr to silence the warning about shift by 8
+          if constexpr (sizeof(IntType) > 1)
+          {
+            for (; i + 1 < sizeof(IntType); ++i)
+            {
+                u[i] = v;
+                v >>= 8;
+            }
+          }
+          u[i] = v;
+
+          stream.write(reinterpret_cast<char*>(u), sizeof(IntType));
+      }
+  }
+
+  // read_little_endian(s, out, N) : read integers in bulk from a little indian stream.
+  // This reads N integers from stream s and put them in array out.
+  template <typename IntType>
+  inline void read_little_endian(std::istream& stream, IntType* out, std::size_t count) {
+      if (IsLittleEndian)
+          stream.read(reinterpret_cast<char*>(out), sizeof(IntType) * count);
+      else
+          for (std::size_t i = 0; i < count; ++i)
+              out[i] = read_little_endian<IntType>(stream);
+  }
+
+  // write_little_endian(s, values, N) : write integers in bulk to a little indian stream.
+  // This takes N integers from array values and writes them on stream s.
+  template <typename IntType>
+  inline void write_little_endian(std::ostream& stream, const IntType* values, std::size_t count) {
+      if (IsLittleEndian)
+          stream.write(reinterpret_cast<const char*>(values), sizeof(IntType) * count);
+      else
+          for (std::size_t i = 0; i < count; ++i)
+              write_little_endian<IntType>(stream, values[i]);
+  }
+
+}  // namespace Stockfish::Eval::NNUE
 
 #endif // #ifndef NNUE_COMMON_H_INCLUDED

src/nnue/nnue_feature_transformer.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -23,72 +23,158 @@
 
 #include "nnue_common.h"
 #include "nnue_architecture.h"
-#include "features/index_list.h"
 
 #include <cstring> // std::memset()
 
-namespace Eval::NNUE {
+namespace Stockfish::Eval::NNUE {
+
+  using BiasType       = std::int16_t;
+  using WeightType     = std::int16_t;
+  using PSQTWeightType = std::int32_t;
 
   // If vector instructions are enabled, we update and refresh the
   // accumulator tile by tile such that each tile fits in the CPU's
   // vector registers.
   #define VECTOR
 
+  static_assert(PSQTBuckets % 8 == 0,
+    "Per feature PSQT values cannot be processed at granularity lower than 8 at a time.");
+
   #ifdef USE_AVX512
   typedef __m512i vec_t;
+  typedef __m256i psqt_vec_t;
   #define vec_load(a) _mm512_load_si512(a)
   #define vec_store(a,b) _mm512_store_si512(a,b)
   #define vec_add_16(a,b) _mm512_add_epi16(a,b)
   #define vec_sub_16(a,b) _mm512_sub_epi16(a,b)
-  static constexpr IndexType kNumRegs = 8; // only 8 are needed
+  #define vec_load_psqt(a) _mm256_load_si256(a)
+  #define vec_store_psqt(a,b) _mm256_store_si256(a,b)
+  #define vec_add_psqt_32(a,b) _mm256_add_epi32(a,b)
+  #define vec_sub_psqt_32(a,b) _mm256_sub_epi32(a,b)
+  #define vec_zero_psqt() _mm256_setzero_si256()
+  #define NumRegistersSIMD 32
 
   #elif USE_AVX2
   typedef __m256i vec_t;
+  typedef __m256i psqt_vec_t;
   #define vec_load(a) _mm256_load_si256(a)
   #define vec_store(a,b) _mm256_store_si256(a,b)
   #define vec_add_16(a,b) _mm256_add_epi16(a,b)
   #define vec_sub_16(a,b) _mm256_sub_epi16(a,b)
-  static constexpr IndexType kNumRegs = 16;
+  #define vec_load_psqt(a) _mm256_load_si256(a)
+  #define vec_store_psqt(a,b) _mm256_store_si256(a,b)
+  #define vec_add_psqt_32(a,b) _mm256_add_epi32(a,b)
+  #define vec_sub_psqt_32(a,b) _mm256_sub_epi32(a,b)
+  #define vec_zero_psqt() _mm256_setzero_si256()
+  #define NumRegistersSIMD 16
 
   #elif USE_SSE2
   typedef __m128i vec_t;
+  typedef __m128i psqt_vec_t;
   #define vec_load(a) (*(a))
   #define vec_store(a,b) *(a)=(b)
   #define vec_add_16(a,b) _mm_add_epi16(a,b)
   #define vec_sub_16(a,b) _mm_sub_epi16(a,b)
-  static constexpr IndexType kNumRegs = Is64Bit ? 16 : 8;
+  #define vec_load_psqt(a) (*(a))
+  #define vec_store_psqt(a,b) *(a)=(b)
+  #define vec_add_psqt_32(a,b) _mm_add_epi32(a,b)
+  #define vec_sub_psqt_32(a,b) _mm_sub_epi32(a,b)
+  #define vec_zero_psqt() _mm_setzero_si128()
+  #define NumRegistersSIMD (Is64Bit ? 16 : 8)
 
   #elif USE_MMX
   typedef __m64 vec_t;
+  typedef __m64 psqt_vec_t;
   #define vec_load(a) (*(a))
   #define vec_store(a,b) *(a)=(b)
   #define vec_add_16(a,b) _mm_add_pi16(a,b)
   #define vec_sub_16(a,b) _mm_sub_pi16(a,b)
-  static constexpr IndexType kNumRegs = 8;
+  #define vec_load_psqt(a) (*(a))
+  #define vec_store_psqt(a,b) *(a)=(b)
+  #define vec_add_psqt_32(a,b) _mm_add_pi32(a,b)
+  #define vec_sub_psqt_32(a,b) _mm_sub_pi32(a,b)
+  #define vec_zero_psqt() _mm_setzero_si64()
+  #define NumRegistersSIMD 8
 
   #elif USE_NEON
   typedef int16x8_t vec_t;
+  typedef int32x4_t psqt_vec_t;
   #define vec_load(a) (*(a))
   #define vec_store(a,b) *(a)=(b)
   #define vec_add_16(a,b) vaddq_s16(a,b)
   #define vec_sub_16(a,b) vsubq_s16(a,b)
-  static constexpr IndexType kNumRegs = 16;
+  #define vec_load_psqt(a) (*(a))
+  #define vec_store_psqt(a,b) *(a)=(b)
+  #define vec_add_psqt_32(a,b) vaddq_s32(a,b)
+  #define vec_sub_psqt_32(a,b) vsubq_s32(a,b)
+  #define vec_zero_psqt() psqt_vec_t{0}
+  #define NumRegistersSIMD 16
 
   #else
   #undef VECTOR
 
   #endif
 
+
+  #ifdef VECTOR
+
+      // Compute optimal SIMD register count for feature transformer accumulation.
+
+      // We use __m* types as template arguments, which causes GCC to emit warnings
+      // about losing some attribute information. This is irrelevant to us as we
+      // only take their size, so the following pragma are harmless.
+      #pragma GCC diagnostic push
+      #pragma GCC diagnostic ignored "-Wignored-attributes"
+
+      template <typename SIMDRegisterType,
+                typename LaneType,
+                int      NumLanes,
+                int      MaxRegisters>
+      static constexpr int BestRegisterCount()
+      {
+          #define RegisterSize  sizeof(SIMDRegisterType)
+          #define LaneSize      sizeof(LaneType)
+
+          static_assert(RegisterSize >= LaneSize);
+          static_assert(MaxRegisters <= NumRegistersSIMD);
+          static_assert(MaxRegisters > 0);
+          static_assert(NumRegistersSIMD > 0);
+          static_assert(RegisterSize % LaneSize == 0);
+          static_assert((NumLanes * LaneSize) % RegisterSize == 0);
+
+          const int ideal = (NumLanes * LaneSize) / RegisterSize;
+          if (ideal <= MaxRegisters)
+            return ideal;
+
+          // Look for the largest divisor of the ideal register count that is smaller than MaxRegisters
+          for (int divisor = MaxRegisters; divisor > 1; --divisor)
+            if (ideal % divisor == 0)
+              return divisor;
+
+          return 1;
+      }
+
+      static constexpr int NumRegs     = BestRegisterCount<vec_t, WeightType, TransformedFeatureDimensions, NumRegistersSIMD>();
+      static constexpr int NumPsqtRegs = BestRegisterCount<psqt_vec_t, PSQTWeightType, PSQTBuckets, NumRegistersSIMD>();
+
+      #pragma GCC diagnostic pop
+
+  #endif
+
+
+
   // Input feature converter
   class FeatureTransformer {
 
    private:
     // Number of output dimensions for one side
-    static constexpr IndexType kHalfDimensions = kTransformedFeatureDimensions;
+    static constexpr IndexType HalfDimensions = TransformedFeatureDimensions;
 
     #ifdef VECTOR
-    static constexpr IndexType kTileHeight = kNumRegs * sizeof(vec_t) / 2;
+    static constexpr IndexType TileHeight = NumRegs * sizeof(vec_t) / 2;
-    static_assert(kHalfDimensions % kTileHeight == 0, "kTileHeight must divide kHalfDimensions");
+    static constexpr IndexType PsqtTileHeight = NumPsqtRegs * sizeof(psqt_vec_t) / 4;
+    static_assert(HalfDimensions % TileHeight == 0, "TileHeight must divide HalfDimensions");
+    static_assert(PSQTBuckets % PsqtTileHeight == 0, "PsqtTileHeight must divide PSQTBuckets");
     #endif
 
    public:
@@ -96,174 +182,213 @@ namespace Eval::NNUE {
     using OutputType = TransformedFeatureType;
 
     // Number of input/output dimensions
-    static constexpr IndexType kInputDimensions = RawFeatures::kDimensions;
+    static constexpr IndexType InputDimensions = FeatureSet::Dimensions;
-    static constexpr IndexType kOutputDimensions = kHalfDimensions * 2;
+    static constexpr IndexType OutputDimensions = HalfDimensions;
 
     // Size of forward propagation buffer
-    static constexpr std::size_t kBufferSize =
+    static constexpr std::size_t BufferSize =
-        kOutputDimensions * sizeof(OutputType);
+        OutputDimensions * sizeof(OutputType);
 
     // Hash value embedded in the evaluation file
-    static constexpr std::uint32_t GetHashValue() {
+    static constexpr std::uint32_t get_hash_value() {
-
+      return FeatureSet::HashValue ^ (OutputDimensions * 2);
-      return RawFeatures::kHashValue ^ kOutputDimensions;
     }
 
     // Read network parameters
-    bool ReadParameters(std::istream& stream) {
+    bool read_parameters(std::istream& stream) {
+
+      read_little_endian<BiasType      >(stream, biases     , HalfDimensions                  );
+      read_little_endian<WeightType    >(stream, weights    , HalfDimensions * InputDimensions);
+      read_little_endian<PSQTWeightType>(stream, psqtWeights, PSQTBuckets    * InputDimensions);
+
+      return !stream.fail();
+    }
+
+    // Write network parameters
+    bool write_parameters(std::ostream& stream) const {
+
+      write_little_endian<BiasType      >(stream, biases     , HalfDimensions                  );
+      write_little_endian<WeightType    >(stream, weights    , HalfDimensions * InputDimensions);
+      write_little_endian<PSQTWeightType>(stream, psqtWeights, PSQTBuckets    * InputDimensions);
 
-      for (std::size_t i = 0; i < kHalfDimensions; ++i)
-        biases_[i] = read_little_endian<BiasType>(stream);
-      for (std::size_t i = 0; i < kHalfDimensions * kInputDimensions; ++i)
-        weights_[i] = read_little_endian<WeightType>(stream);
       return !stream.fail();
     }
 
     // Convert input features
-    void Transform(const Position& pos, OutputType* output) const {
+    std::int32_t transform(const Position& pos, OutputType* output, int bucket) const {
-
+      update_accumulator(pos, WHITE);
-      UpdateAccumulator(pos, WHITE);
+      update_accumulator(pos, BLACK);
-      UpdateAccumulator(pos, BLACK);
-
-      const auto& accumulation = pos.state()->accumulator.accumulation;
-
-  #if defined(USE_AVX512)
-      constexpr IndexType kNumChunks = kHalfDimensions / (kSimdWidth * 2);
-      static_assert(kHalfDimensions % (kSimdWidth * 2) == 0);
-      const __m512i kControl = _mm512_setr_epi64(0, 2, 4, 6, 1, 3, 5, 7);
-      const __m512i kZero = _mm512_setzero_si512();
-
-  #elif defined(USE_AVX2)
-      constexpr IndexType kNumChunks = kHalfDimensions / kSimdWidth;
-      constexpr int kControl = 0b11011000;
-      const __m256i kZero = _mm256_setzero_si256();
-
-  #elif defined(USE_SSE2)
-      constexpr IndexType kNumChunks = kHalfDimensions / kSimdWidth;
-
-  #ifdef USE_SSE41
-      const __m128i kZero = _mm_setzero_si128();
-  #else
-      const __m128i k0x80s = _mm_set1_epi8(-128);
-  #endif
-
-  #elif defined(USE_MMX)
-      constexpr IndexType kNumChunks = kHalfDimensions / kSimdWidth;
-      const __m64 k0x80s = _mm_set1_pi8(-128);
-
-  #elif defined(USE_NEON)
-      constexpr IndexType kNumChunks = kHalfDimensions / (kSimdWidth / 2);
-      const int8x8_t kZero = {0};
-  #endif
 
       const Color perspectives[2] = {pos.side_to_move(), ~pos.side_to_move()};
-      for (IndexType p = 0; p < 2; ++p) {
+      const auto& accumulation = pos.state()->accumulator.accumulation;
-        const IndexType offset = kHalfDimensions * p;
+      const auto& psqtAccumulation = pos.state()->accumulator.psqtAccumulation;
 
-  #if defined(USE_AVX512)
+      const auto psqt = (
-        auto out = reinterpret_cast<__m512i*>(&output[offset]);
+            psqtAccumulation[perspectives[0]][bucket]
-        for (IndexType j = 0; j < kNumChunks; ++j) {
+          - psqtAccumulation[perspectives[1]][bucket]
-          __m512i sum0 = _mm512_load_si512(
+        ) / 2;
-              &reinterpret_cast<const __m512i*>(accumulation[perspectives[p]][0])[j * 2 + 0]);
-          __m512i sum1 = _mm512_load_si512(
-              &reinterpret_cast<const __m512i*>(accumulation[perspectives[p]][0])[j * 2 + 1]);
-          _mm512_store_si512(&out[j], _mm512_permutexvar_epi64(kControl,
-              _mm512_max_epi8(_mm512_packs_epi16(sum0, sum1), kZero)));
-        }
 
-  #elif defined(USE_AVX2)
-        auto out = reinterpret_cast<__m256i*>(&output[offset]);
-        for (IndexType j = 0; j < kNumChunks; ++j) {
-          __m256i sum0 = _mm256_load_si256(
-              &reinterpret_cast<const __m256i*>(accumulation[perspectives[p]][0])[j * 2 + 0]);
-          __m256i sum1 = _mm256_load_si256(
-              &reinterpret_cast<const __m256i*>(accumulation[perspectives[p]][0])[j * 2 + 1]);
-          _mm256_store_si256(&out[j], _mm256_permute4x64_epi64(_mm256_max_epi8(
-              _mm256_packs_epi16(sum0, sum1), kZero), kControl));
-        }
 
-  #elif defined(USE_SSE2)
+      for (IndexType p = 0; p < 2; ++p)
-        auto out = reinterpret_cast<__m128i*>(&output[offset]);
+      {
-        for (IndexType j = 0; j < kNumChunks; ++j) {
+          const IndexType offset = (HalfDimensions / 2) * p;
-          __m128i sum0 = _mm_load_si128(&reinterpret_cast<const __m128i*>(
-              accumulation[perspectives[p]][0])[j * 2 + 0]);
-          __m128i sum1 = _mm_load_si128(&reinterpret_cast<const __m128i*>(
-              accumulation[perspectives[p]][0])[j * 2 + 1]);
-      const __m128i packedbytes = _mm_packs_epi16(sum0, sum1);
 
-          _mm_store_si128(&out[j],
+#if defined(USE_AVX512)
 
-  #ifdef USE_SSE41
+          constexpr IndexType OutputChunkSize = 512 / 8;
-              _mm_max_epi8(packedbytes, kZero)
+          static_assert((HalfDimensions / 2) % OutputChunkSize == 0);
-  #else
+          constexpr IndexType NumOutputChunks = HalfDimensions / 2 / OutputChunkSize;
-              _mm_subs_epi8(_mm_adds_epi8(packedbytes, k0x80s), k0x80s)
-  #endif
 
-          );
+          const __m512i Zero = _mm512_setzero_si512();
-        }
+          const __m512i One = _mm512_set1_epi16(127);
+          const __m512i Control = _mm512_setr_epi64(0, 2, 4, 6, 1, 3, 5, 7);
 
-  #elif defined(USE_MMX)
+          const __m512i* in0 = reinterpret_cast<const __m512i*>(&(accumulation[perspectives[p]][0]));
-        auto out = reinterpret_cast<__m64*>(&output[offset]);
+          const __m512i* in1 = reinterpret_cast<const __m512i*>(&(accumulation[perspectives[p]][HalfDimensions / 2]));
-        for (IndexType j = 0; j < kNumChunks; ++j) {
+                __m512i* out = reinterpret_cast<      __m512i*>(output + offset);
-          __m64 sum0 = *(&reinterpret_cast<const __m64*>(
-              accumulation[perspectives[p]][0])[j * 2 + 0]);
-          __m64 sum1 = *(&reinterpret_cast<const __m64*>(
-              accumulation[perspectives[p]][0])[j * 2 + 1]);
-          const __m64 packedbytes = _mm_packs_pi16(sum0, sum1);
-          out[j] = _mm_subs_pi8(_mm_adds_pi8(packedbytes, k0x80s), k0x80s);
-        }
 
-  #elif defined(USE_NEON)
+          for (IndexType j = 0; j < NumOutputChunks; j += 1)
-        const auto out = reinterpret_cast<int8x8_t*>(&output[offset]);
+          {
-        for (IndexType j = 0; j < kNumChunks; ++j) {
+              const __m512i sum0a = _mm512_max_epi16(_mm512_min_epi16(in0[j * 2 + 0], One), Zero);
-          int16x8_t sum = reinterpret_cast<const int16x8_t*>(
+              const __m512i sum0b = _mm512_max_epi16(_mm512_min_epi16(in0[j * 2 + 1], One), Zero);
-              accumulation[perspectives[p]][0])[j];
+              const __m512i sum1a = _mm512_max_epi16(_mm512_min_epi16(in1[j * 2 + 0], One), Zero);
-          out[j] = vmax_s8(vqmovn_s16(sum), kZero);
+              const __m512i sum1b = _mm512_max_epi16(_mm512_min_epi16(in1[j * 2 + 1], One), Zero);
-        }
 
-  #else
+              const __m512i pa = _mm512_srli_epi16(_mm512_mullo_epi16(sum0a, sum1a), 7);
-        for (IndexType j = 0; j < kHalfDimensions; ++j) {
+              const __m512i pb = _mm512_srli_epi16(_mm512_mullo_epi16(sum0b, sum1b), 7);
-          BiasType sum = accumulation[static_cast<int>(perspectives[p])][0][j];
-          output[offset + j] = static_cast<OutputType>(
-              std::max<int>(0, std::min<int>(127, sum)));
-        }
-  #endif
 
+              out[j] = _mm512_permutexvar_epi64(Control, _mm512_packs_epi16(pa, pb));
+          }
+
+#elif defined(USE_AVX2)
+
+          constexpr IndexType OutputChunkSize = 256 / 8;
+          static_assert((HalfDimensions / 2) % OutputChunkSize == 0);
+          constexpr IndexType NumOutputChunks = HalfDimensions / 2 / OutputChunkSize;
+
+          const __m256i Zero = _mm256_setzero_si256();
+          const __m256i One = _mm256_set1_epi16(127);
+          constexpr int Control = 0b11011000;
+
+          const __m256i* in0 = reinterpret_cast<const __m256i*>(&(accumulation[perspectives[p]][0]));
+          const __m256i* in1 = reinterpret_cast<const __m256i*>(&(accumulation[perspectives[p]][HalfDimensions / 2]));
+                __m256i* out = reinterpret_cast<      __m256i*>(output + offset);
+
+          for (IndexType j = 0; j < NumOutputChunks; j += 1)
+          {
+              const __m256i sum0a = _mm256_max_epi16(_mm256_min_epi16(in0[j * 2 + 0], One), Zero);
+              const __m256i sum0b = _mm256_max_epi16(_mm256_min_epi16(in0[j * 2 + 1], One), Zero);
+              const __m256i sum1a = _mm256_max_epi16(_mm256_min_epi16(in1[j * 2 + 0], One), Zero);
+              const __m256i sum1b = _mm256_max_epi16(_mm256_min_epi16(in1[j * 2 + 1], One), Zero);
+
+              const __m256i pa = _mm256_srli_epi16(_mm256_mullo_epi16(sum0a, sum1a), 7);
+              const __m256i pb = _mm256_srli_epi16(_mm256_mullo_epi16(sum0b, sum1b), 7);
+
+              out[j] = _mm256_permute4x64_epi64(_mm256_packs_epi16(pa, pb), Control);
+          }
+
+#elif defined(USE_SSE2)
+
+          constexpr IndexType OutputChunkSize = 128 / 8;
+          static_assert((HalfDimensions / 2) % OutputChunkSize == 0);
+          constexpr IndexType NumOutputChunks = HalfDimensions / 2 / OutputChunkSize;
+
+          const __m128i Zero = _mm_setzero_si128();
+          const __m128i One = _mm_set1_epi16(127);
+
+          const __m128i* in0 = reinterpret_cast<const __m128i*>(&(accumulation[perspectives[p]][0]));
+          const __m128i* in1 = reinterpret_cast<const __m128i*>(&(accumulation[perspectives[p]][HalfDimensions / 2]));
+                __m128i* out = reinterpret_cast<      __m128i*>(output + offset);
+
+          for (IndexType j = 0; j < NumOutputChunks; j += 1)
+          {
+              const __m128i sum0a = _mm_max_epi16(_mm_min_epi16(in0[j * 2 + 0], One), Zero);
+              const __m128i sum0b = _mm_max_epi16(_mm_min_epi16(in0[j * 2 + 1], One), Zero);
+              const __m128i sum1a = _mm_max_epi16(_mm_min_epi16(in1[j * 2 + 0], One), Zero);
+              const __m128i sum1b = _mm_max_epi16(_mm_min_epi16(in1[j * 2 + 1], One), Zero);
+
+              const __m128i pa = _mm_srli_epi16(_mm_mullo_epi16(sum0a, sum1a), 7);
+              const __m128i pb = _mm_srli_epi16(_mm_mullo_epi16(sum0b, sum1b), 7);
+
+              out[j] = _mm_packs_epi16(pa, pb);
+          }
+
+#elif defined(USE_NEON)
+
+          constexpr IndexType OutputChunkSize = 128 / 8;
+          static_assert((HalfDimensions / 2) % OutputChunkSize == 0);
+          constexpr IndexType NumOutputChunks = HalfDimensions / 2 / OutputChunkSize;
+
+          const int16x8_t Zero = vdupq_n_s16(0);
+          const int16x8_t One  = vdupq_n_s16(127);
+
+          const int16x8_t* in0 = reinterpret_cast<const int16x8_t*>(&(accumulation[perspectives[p]][0]));
+          const int16x8_t* in1 = reinterpret_cast<const int16x8_t*>(&(accumulation[perspectives[p]][HalfDimensions / 2]));
+                int8x16_t* out = reinterpret_cast<      int8x16_t*>(output + offset);
+
+          for (IndexType j = 0; j < NumOutputChunks; j += 1)
+          {
+              const int16x8_t sum0a = vmaxq_s16(vminq_s16(in0[j * 2 + 0], One), Zero);
+              const int16x8_t sum0b = vmaxq_s16(vminq_s16(in0[j * 2 + 1], One), Zero);
+              const int16x8_t sum1a = vmaxq_s16(vminq_s16(in1[j * 2 + 0], One), Zero);
+              const int16x8_t sum1b = vmaxq_s16(vminq_s16(in1[j * 2 + 1], One), Zero);
+
+              const int8x8_t pa = vshrn_n_s16(vmulq_s16(sum0a, sum1a), 7);
+              const int8x8_t pb = vshrn_n_s16(vmulq_s16(sum0b, sum1b), 7);
+
+              out[j] = vcombine_s8(pa, pb);
+          }
+
+#else
+
+          for (IndexType j = 0; j < HalfDimensions / 2; ++j) {
+              BiasType sum0 = accumulation[static_cast<int>(perspectives[p])][j + 0];
+              BiasType sum1 = accumulation[static_cast<int>(perspectives[p])][j + HalfDimensions / 2];
+              sum0 = std::max<int>(0, std::min<int>(127, sum0));
+              sum1 = std::max<int>(0, std::min<int>(127, sum1));
+              output[offset + j] = static_cast<OutputType>(sum0 * sum1 / 128);
+          }
+
+#endif
       }
-  #if defined(USE_MMX)
+
-      _mm_empty();
+      return psqt;
-  #endif
+
-    }
+   } // end of function transform()
+
+
 
    private:
-    void UpdateAccumulator(const Position& pos, const Color c) const {
+    void update_accumulator(const Position& pos, const Color perspective) const {
+
+      // The size must be enough to contain the largest possible update.
+      // That might depend on the feature set and generally relies on the
+      // feature set's update cost calculation to be correct and never
+      // allow updates with more added/removed features than MaxActiveDimensions.
 
   #ifdef VECTOR
       // Gcc-10.2 unnecessarily spills AVX2 registers if this array
       // is defined in the VECTOR code below, once in each branch
-      vec_t acc[kNumRegs];
+      vec_t acc[NumRegs];
+      psqt_vec_t psqt[NumPsqtRegs];
   #endif
 
       // Look for a usable accumulator of an earlier position. We keep track
       // of the estimated gain in terms of features to be added/subtracted.
       StateInfo *st = pos.state(), *next = nullptr;
-      int gain = pos.count<ALL_PIECES>() - 2;
+      int gain = FeatureSet::refresh_cost(pos);
-      while (st->accumulator.state[c] == EMPTY)
+      while (st->previous && !st->accumulator.computed[perspective])
       {
-        auto& dp = st->dirtyPiece;
+        // This governs when a full feature refresh is needed and how many
-        // The first condition tests whether an incremental update is
+        // updates are better than just one full refresh.
-        // possible at all: if this side's king has moved, it is not possible.
+        if (   FeatureSet::requires_refresh(st, perspective)
-        static_assert(std::is_same_v<RawFeatures::SortedTriggerSet,
+            || (gain -= FeatureSet::update_cost(st) + 1) < 0)
-              Features::CompileTimeList<Features::TriggerEvent, Features::TriggerEvent::kFriendKingMoved>>,
-              "Current code assumes that only kFriendlyKingMoved refresh trigger is being used.");
-        if (   dp.piece[0] == make_piece(c, KING)
-            || (gain -= dp.dirty_num + 1) < 0)
           break;
         next = st;
         st = st->previous;
       }
 
-      if (st->accumulator.state[c] == COMPUTED)
+      if (st->accumulator.computed[perspective])
       {
         if (next == nullptr)
           return;
@@ -271,85 +396,129 @@ namespace Eval::NNUE {
         // Update incrementally in two steps. First, we update the "next"
         // accumulator. Then, we update the current accumulator (pos.state()).
 
-        // Gather all features to be updated. This code assumes HalfKP features
+        // Gather all features to be updated.
-        // only and doesn't support refresh triggers.
+        const Square ksq = pos.square<KING>(perspective);
-        static_assert(std::is_same_v<Features::FeatureSet<Features::HalfKP<Features::Side::kFriend>>,
+        FeatureSet::IndexList removed[2], added[2];
-                                     RawFeatures>);
+        FeatureSet::append_changed_indices(
-        Features::IndexList removed[2], added[2];
+          ksq, next->dirtyPiece, perspective, removed[0], added[0]);
-        Features::HalfKP<Features::Side::kFriend>::AppendChangedIndices(pos,
-            next->dirtyPiece, c, &removed[0], &added[0]);
         for (StateInfo *st2 = pos.state(); st2 != next; st2 = st2->previous)
-          Features::HalfKP<Features::Side::kFriend>::AppendChangedIndices(pos,
+          FeatureSet::append_changed_indices(
-              st2->dirtyPiece, c, &removed[1], &added[1]);
+            ksq, st2->dirtyPiece, perspective, removed[1], added[1]);
 
         // Mark the accumulators as computed.
-        next->accumulator.state[c] = COMPUTED;
+        next->accumulator.computed[perspective] = true;
-        pos.state()->accumulator.state[c] = COMPUTED;
+        pos.state()->accumulator.computed[perspective] = true;
 
-        // Now update the accumulators listed in info[], where the last element is a sentinel.
+        // Now update the accumulators listed in states_to_update[], where the last element is a sentinel.
-        StateInfo *info[3] =
+        StateInfo *states_to_update[3] =
           { next, next == pos.state() ? nullptr : pos.state(), nullptr };
   #ifdef VECTOR
-        for (IndexType j = 0; j < kHalfDimensions / kTileHeight; ++j)
+        for (IndexType j = 0; j < HalfDimensions / TileHeight; ++j)
         {
           // Load accumulator
           auto accTile = reinterpret_cast<vec_t*>(
-            &st->accumulator.accumulation[c][0][j * kTileHeight]);
+            &st->accumulator.accumulation[perspective][j * TileHeight]);
-          for (IndexType k = 0; k < kNumRegs; ++k)
+          for (IndexType k = 0; k < NumRegs; ++k)
             acc[k] = vec_load(&accTile[k]);
 
-          for (IndexType i = 0; info[i]; ++i)
+          for (IndexType i = 0; states_to_update[i]; ++i)
           {
             // Difference calculation for the deactivated features
             for (const auto index : removed[i])
             {
-              const IndexType offset = kHalfDimensions * index + j * kTileHeight;
+              const IndexType offset = HalfDimensions * index + j * TileHeight;
-              auto column = reinterpret_cast<const vec_t*>(&weights_[offset]);
+              auto column = reinterpret_cast<const vec_t*>(&weights[offset]);
-              for (IndexType k = 0; k < kNumRegs; ++k)
+              for (IndexType k = 0; k < NumRegs; ++k)
                 acc[k] = vec_sub_16(acc[k], column[k]);
             }
 
             // Difference calculation for the activated features
             for (const auto index : added[i])
             {
-              const IndexType offset = kHalfDimensions * index + j * kTileHeight;
+              const IndexType offset = HalfDimensions * index + j * TileHeight;
-              auto column = reinterpret_cast<const vec_t*>(&weights_[offset]);
+              auto column = reinterpret_cast<const vec_t*>(&weights[offset]);
-              for (IndexType k = 0; k < kNumRegs; ++k)
+              for (IndexType k = 0; k < NumRegs; ++k)
                 acc[k] = vec_add_16(acc[k], column[k]);
             }
 
             // Store accumulator
             accTile = reinterpret_cast<vec_t*>(
-              &info[i]->accumulator.accumulation[c][0][j * kTileHeight]);
+              &states_to_update[i]->accumulator.accumulation[perspective][j * TileHeight]);
-            for (IndexType k = 0; k < kNumRegs; ++k)
+            for (IndexType k = 0; k < NumRegs; ++k)
               vec_store(&accTile[k], acc[k]);
           }
         }
 
-  #else
+        for (IndexType j = 0; j < PSQTBuckets / PsqtTileHeight; ++j)
-        for (IndexType i = 0; info[i]; ++i)
         {
-          std::memcpy(info[i]->accumulator.accumulation[c][0],
+          // Load accumulator
-              st->accumulator.accumulation[c][0],
+          auto accTilePsqt = reinterpret_cast<psqt_vec_t*>(
-              kHalfDimensions * sizeof(BiasType));
+            &st->accumulator.psqtAccumulation[perspective][j * PsqtTileHeight]);
-          st = info[i];
+          for (std::size_t k = 0; k < NumPsqtRegs; ++k)
+            psqt[k] = vec_load_psqt(&accTilePsqt[k]);
+
+          for (IndexType i = 0; states_to_update[i]; ++i)
+          {
+            // Difference calculation for the deactivated features
+            for (const auto index : removed[i])
+            {
+              const IndexType offset = PSQTBuckets * index + j * PsqtTileHeight;
+              auto columnPsqt = reinterpret_cast<const psqt_vec_t*>(&psqtWeights[offset]);
+              for (std::size_t k = 0; k < NumPsqtRegs; ++k)
+                psqt[k] = vec_sub_psqt_32(psqt[k], columnPsqt[k]);
+            }
+
+            // Difference calculation for the activated features
+            for (const auto index : added[i])
+            {
+              const IndexType offset = PSQTBuckets * index + j * PsqtTileHeight;
+              auto columnPsqt = reinterpret_cast<const psqt_vec_t*>(&psqtWeights[offset]);
+              for (std::size_t k = 0; k < NumPsqtRegs; ++k)
+                psqt[k] = vec_add_psqt_32(psqt[k], columnPsqt[k]);
+            }
+
+            // Store accumulator
+            accTilePsqt = reinterpret_cast<psqt_vec_t*>(
+              &states_to_update[i]->accumulator.psqtAccumulation[perspective][j * PsqtTileHeight]);
+            for (std::size_t k = 0; k < NumPsqtRegs; ++k)
+              vec_store_psqt(&accTilePsqt[k], psqt[k]);
+          }
+        }
+
+  #else
+        for (IndexType i = 0; states_to_update[i]; ++i)
+        {
+          std::memcpy(states_to_update[i]->accumulator.accumulation[perspective],
+              st->accumulator.accumulation[perspective],
+              HalfDimensions * sizeof(BiasType));
+
+          for (std::size_t k = 0; k < PSQTBuckets; ++k)
+            states_to_update[i]->accumulator.psqtAccumulation[perspective][k] = st->accumulator.psqtAccumulation[perspective][k];
+
+          st = states_to_update[i];
 
           // Difference calculation for the deactivated features
           for (const auto index : removed[i])
           {
-            const IndexType offset = kHalfDimensions * index;
+            const IndexType offset = HalfDimensions * index;
 
-            for (IndexType j = 0; j < kHalfDimensions; ++j)
+            for (IndexType j = 0; j < HalfDimensions; ++j)
-              st->accumulator.accumulation[c][0][j] -= weights_[offset + j];
+              st->accumulator.accumulation[perspective][j] -= weights[offset + j];
+
+            for (std::size_t k = 0; k < PSQTBuckets; ++k)
+              st->accumulator.psqtAccumulation[perspective][k] -= psqtWeights[index * PSQTBuckets + k];
           }
 
           // Difference calculation for the activated features
           for (const auto index : added[i])
           {
-            const IndexType offset = kHalfDimensions * index;
+            const IndexType offset = HalfDimensions * index;
 
-            for (IndexType j = 0; j < kHalfDimensions; ++j)
+            for (IndexType j = 0; j < HalfDimensions; ++j)
-              st->accumulator.accumulation[c][0][j] += weights_[offset + j];
+              st->accumulator.accumulation[perspective][j] += weights[offset + j];
+
+            for (std::size_t k = 0; k < PSQTBuckets; ++k)
+              st->accumulator.psqtAccumulation[perspective][k] += psqtWeights[index * PSQTBuckets + k];
           }
         }
   #endif
@@ -358,43 +527,69 @@ namespace Eval::NNUE {
       {
         // Refresh the accumulator
         auto& accumulator = pos.state()->accumulator;
-        accumulator.state[c] = COMPUTED;
+        accumulator.computed[perspective] = true;
-        Features::IndexList active;
+        FeatureSet::IndexList active;
-        Features::HalfKP<Features::Side::kFriend>::AppendActiveIndices(pos, c, &active);
+        FeatureSet::append_active_indices(pos, perspective, active);
 
   #ifdef VECTOR
-        for (IndexType j = 0; j < kHalfDimensions / kTileHeight; ++j)
+        for (IndexType j = 0; j < HalfDimensions / TileHeight; ++j)
         {
           auto biasesTile = reinterpret_cast<const vec_t*>(
-              &biases_[j * kTileHeight]);
+              &biases[j * TileHeight]);
-          for (IndexType k = 0; k < kNumRegs; ++k)
+          for (IndexType k = 0; k < NumRegs; ++k)
             acc[k] = biasesTile[k];
 
           for (const auto index : active)
           {
-            const IndexType offset = kHalfDimensions * index + j * kTileHeight;
+            const IndexType offset = HalfDimensions * index + j * TileHeight;
-            auto column = reinterpret_cast<const vec_t*>(&weights_[offset]);
+            auto column = reinterpret_cast<const vec_t*>(&weights[offset]);
 
-            for (unsigned k = 0; k < kNumRegs; ++k)
+            for (unsigned k = 0; k < NumRegs; ++k)
               acc[k] = vec_add_16(acc[k], column[k]);
           }
 
           auto accTile = reinterpret_cast<vec_t*>(
-              &accumulator.accumulation[c][0][j * kTileHeight]);
+              &accumulator.accumulation[perspective][j * TileHeight]);
-          for (unsigned k = 0; k < kNumRegs; k++)
+          for (unsigned k = 0; k < NumRegs; k++)
             vec_store(&accTile[k], acc[k]);
         }
 
+        for (IndexType j = 0; j < PSQTBuckets / PsqtTileHeight; ++j)
+        {
+          for (std::size_t k = 0; k < NumPsqtRegs; ++k)
+            psqt[k] = vec_zero_psqt();
+
+          for (const auto index : active)
+          {
+            const IndexType offset = PSQTBuckets * index + j * PsqtTileHeight;
+            auto columnPsqt = reinterpret_cast<const psqt_vec_t*>(&psqtWeights[offset]);
+
+            for (std::size_t k = 0; k < NumPsqtRegs; ++k)
+              psqt[k] = vec_add_psqt_32(psqt[k], columnPsqt[k]);
+          }
+
+          auto accTilePsqt = reinterpret_cast<psqt_vec_t*>(
+            &accumulator.psqtAccumulation[perspective][j * PsqtTileHeight]);
+          for (std::size_t k = 0; k < NumPsqtRegs; ++k)
+            vec_store_psqt(&accTilePsqt[k], psqt[k]);
+        }
+
   #else
-        std::memcpy(accumulator.accumulation[c][0], biases_,
+        std::memcpy(accumulator.accumulation[perspective], biases,
-            kHalfDimensions * sizeof(BiasType));
+            HalfDimensions * sizeof(BiasType));
+
+        for (std::size_t k = 0; k < PSQTBuckets; ++k)
+          accumulator.psqtAccumulation[perspective][k] = 0;
 
         for (const auto index : active)
         {
-          const IndexType offset = kHalfDimensions * index;
+          const IndexType offset = HalfDimensions * index;
 
-          for (IndexType j = 0; j < kHalfDimensions; ++j)
+          for (IndexType j = 0; j < HalfDimensions; ++j)
-            accumulator.accumulation[c][0][j] += weights_[offset + j];
+            accumulator.accumulation[perspective][j] += weights[offset + j];
+
+          for (std::size_t k = 0; k < PSQTBuckets; ++k)
+            accumulator.psqtAccumulation[perspective][k] += psqtWeights[index * PSQTBuckets + k];
         }
   #endif
       }
@@ -404,14 +599,11 @@ namespace Eval::NNUE {
   #endif
     }
 
-    using BiasType = std::int16_t;
+    alignas(CacheLineSize) BiasType biases[HalfDimensions];
-    using WeightType = std::int16_t;
+    alignas(CacheLineSize) WeightType weights[HalfDimensions * InputDimensions];
-
+    alignas(CacheLineSize) PSQTWeightType psqtWeights[InputDimensions * PSQTBuckets];
-    alignas(kCacheLineSize) BiasType biases_[kHalfDimensions];
-    alignas(kCacheLineSize)
-        WeightType weights_[kHalfDimensions * kInputDimensions];
   };
 
-}  // namespace Eval::NNUE
+}  // namespace Stockfish::Eval::NNUE
 
 #endif // #ifndef NNUE_FEATURE_TRANSFORMER_H_INCLUDED

src/pawns.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -24,6 +24,8 @@
 #include "position.h"
 #include "thread.h"
 
+namespace Stockfish {
+
 namespace {
 
   #define V Value
@@ -107,8 +109,9 @@ namespace {
     e->blockedCount += popcount(shift<Up>(ourPawns) & (theirPawns | doubleAttackThem));
 
     // Loop through all pawns of the current color and score each pawn
-    while (b) {
+    while (b)
-        s = pop_lsb(&b);
+    {
+        s = pop_lsb(b);
 
         assert(pos.piece_on(s) == make_piece(Us, PAWN));
 
@@ -288,7 +291,7 @@ Score Entry::do_king_safety(const Position& pos) {
   if (pawns & attacks_bb<KING>(ksq))
       minPawnDist = 1;
   else while (pawns)
-      minPawnDist = std::min(minPawnDist, distance(ksq, pop_lsb(&pawns)));
+      minPawnDist = std::min(minPawnDist, distance(ksq, pop_lsb(pawns)));
 
   return shelter - make_score(0, 16 * minPawnDist);
 }
@@ -298,3 +301,5 @@ template Score Entry::do_king_safety<WHITE>(const Position& pos);
 template Score Entry::do_king_safety<BLACK>(const Position& pos);
 
 } // namespace Pawns
+
+} // namespace Stockfish

src/pawns.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -23,7 +23,7 @@
 #include "position.h"
 #include "types.h"
 
-namespace Pawns {
+namespace Stockfish::Pawns {
 
 /// Pawns::Entry contains various information about a pawn structure. A lookup
 /// to the pawn hash table (performed by calling the probe function) returns a
@@ -65,6 +65,6 @@ typedef HashTable<Entry, 131072> Table;
 
 Entry* probe(const Position& pos);
 
-} // namespace Pawns
+} // namespace Stockfish::Pawns
 
 #endif // #ifndef PAWNS_H_INCLUDED

src/position.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -34,6 +34,8 @@
 
 using std::string;
 
+namespace Stockfish {
+
 namespace Zobrist {
 
   Key psq[PIECE_NB][SQUARE_NB];
@@ -71,13 +73,13 @@ std::ostream& operator<<(std::ostream& os, const Position& pos) {
      << std::setfill(' ') << std::dec << "\nCheckers: ";
 
   for (Bitboard b = pos.checkers(); b; )
-      os << UCI::square(pop_lsb(&b)) << " ";
+      os << UCI::square(pop_lsb(b)) << " ";
 
   if (    int(Tablebases::MaxCardinality) >= popcount(pos.pieces())
       && !pos.can_castle(ANY_CASTLING))
   {
       StateInfo st;
-      ASSERT_ALIGNED(&st, Eval::NNUE::kCacheLineSize);
+      ASSERT_ALIGNED(&st, Eval::NNUE::CacheLineSize);
 
       Position p;
       p.set(pos.fen(), pos.is_chess960(), &st, pos.this_thread());
@@ -249,8 +251,6 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th
       set_castling_right(c, rsq);
   }
 
-  set_state(st);
-
   // 4. En passant square.
   // Ignore if square is invalid or not on side to move relative rank 6.
   bool enpassant = false;
@@ -264,24 +264,12 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th
       // a) side to move have a pawn threatening epSquare
       // b) there is an enemy pawn in front of epSquare
       // c) there is no piece on epSquare or behind epSquare
-      // d) enemy pawn didn't block a check of its own color by moving forward
       enpassant = pawn_attacks_bb(~sideToMove, st->epSquare) & pieces(sideToMove, PAWN)
                && (pieces(~sideToMove, PAWN) & (st->epSquare + pawn_push(~sideToMove)))
-               && !(pieces() & (st->epSquare | (st->epSquare + pawn_push(sideToMove))))
+               && !(pieces() & (st->epSquare | (st->epSquare + pawn_push(sideToMove))));
-               && (   file_of(square<KING>(sideToMove)) == file_of(st->epSquare)
-                   || !(blockers_for_king(sideToMove) & (st->epSquare + pawn_push(~sideToMove))));
   }
 
-  // It's necessary for st->previous to be intialized in this way because legality check relies on its existence
+  if (!enpassant)
-  if (enpassant) {
-      st->previous = new StateInfo();
-      remove_piece(st->epSquare - pawn_push(sideToMove));
-      st->previous->checkersBB = attackers_to(square<KING>(~sideToMove)) & pieces(sideToMove);
-      st->previous->blockersForKing[WHITE] = slider_blockers(pieces(BLACK), square<KING>(WHITE), st->previous->pinners[BLACK]);
-      st->previous->blockersForKing[BLACK] = slider_blockers(pieces(WHITE), square<KING>(BLACK), st->previous->pinners[WHITE]);
-      put_piece(make_piece(~sideToMove, PAWN), st->epSquare - pawn_push(sideToMove));
-  }
-  else
       st->epSquare = SQ_NONE;
 
   // 5-6. Halfmove clock and fullmove number
@@ -293,8 +281,7 @@ Position& Position::set(const string& fenStr, bool isChess960, StateInfo* si, Th
 
   chess960 = isChess960;
   thisThread = th;
-  st->accumulator.state[WHITE] = Eval::NNUE::INIT;
+  set_state(st);
-  st->accumulator.state[BLACK] = Eval::NNUE::INIT;
 
   assert(pos_is_ok());
 
@@ -318,7 +305,7 @@ void Position::set_castling_right(Color c, Square rfrom) {
   Square kto = relative_square(c, cr & KING_SIDE ? SQ_G1 : SQ_C1);
   Square rto = relative_square(c, cr & KING_SIDE ? SQ_F1 : SQ_D1);
 
-  castlingPath[cr] =   (between_bb(rfrom, rto) | between_bb(kfrom, kto) | rto | kto)
+  castlingPath[cr] =   (between_bb(rfrom, rto) | between_bb(kfrom, kto))
                     & ~(kfrom | rfrom);
 }
 
@@ -357,7 +344,7 @@ void Position::set_state(StateInfo* si) const {
 
   for (Bitboard b = pieces(); b; )
   {
-      Square s = pop_lsb(&b);
+      Square s = pop_lsb(b);
       Piece pc = piece_on(s);
       si->key ^= Zobrist::psq[pc][s];
 
@@ -408,7 +395,7 @@ Position& Position::set(const string& code, Color c, StateInfo* si) {
 /// Position::fen() returns a FEN representation of the position. In case of
 /// Chess960 the Shredder-FEN notation is used. This is mainly a debugging function.
 
-const string Position::fen() const {
+string Position::fen() const {
 
   int emptyCnt;
   std::ostringstream ss;
@@ -474,7 +461,7 @@ Bitboard Position::slider_blockers(Bitboard sliders, Square s, Bitboard& pinners
 
   while (snipers)
   {
-    Square sniperSq = pop_lsb(&snipers);
+    Square sniperSq = pop_lsb(snipers);
     Bitboard b = between_bb(s, sniperSq) & occupancy;
 
     if (b && !more_than_one(b))
@@ -515,11 +502,23 @@ bool Position::legal(Move m) const {
   assert(color_of(moved_piece(m)) == us);
   assert(piece_on(square<KING>(us)) == make_piece(us, KING));
 
-  // st->previous->blockersForKing consider capsq as empty.
+  // En passant captures are a tricky special case. Because they are rather
-  // If pinned, it has to move along the king ray.
+  // uncommon, we do it simply by testing whether the king is attacked after
+  // the move is made.
   if (type_of(m) == EN_PASSANT)
-      return   !(st->previous->blockersForKing[sideToMove] & from)
+  {
-            || aligned(from, to, square<KING>(us));
+      Square ksq = square<KING>(us);
+      Square capsq = to - pawn_push(us);
+      Bitboard occupied = (pieces() ^ from ^ capsq) | to;
+
+      assert(to == ep_square());
+      assert(moved_piece(m) == make_piece(us, PAWN));
+      assert(piece_on(capsq) == make_piece(~us, PAWN));
+      assert(piece_on(to) == NO_PIECE);
+
+      return   !(attacks_bb<  ROOK>(ksq, occupied) & pieces(~us, QUEEN, ROOK))
+            && !(attacks_bb<BISHOP>(ksq, occupied) & pieces(~us, QUEEN, BISHOP));
+  }
 
   // Castling moves generation does not check if the castling path is clear of
   // enemy attacks, it is delayed at a later time: now!
@@ -542,7 +541,7 @@ bool Position::legal(Move m) const {
   // If the moving piece is a king, check whether the destination square is
   // attacked by the opponent.
   if (type_of(piece_on(from)) == KING)
-      return !(attackers_to(to) & pieces(~us));
+      return !(attackers_to(to, pieces() ^ from) & pieces(~us));
 
   // A non-king move is legal if and only if it is not pinned or it
   // is moving along the ray towards or away from the king.
@@ -611,8 +610,8 @@ bool Position::pseudo_legal(const Move m) const {
           if (more_than_one(checkers()))
               return false;
 
-          // Our move must be a blocking evasion or a capture of the checking piece
+          // Our move must be a blocking interposition or a capture of the checking piece
-          if (!((between_bb(lsb(checkers()), square<KING>(us)) | checkers()) & to))
+          if (!(between_bb(square<KING>(us), lsb(checkers())) & to))
               return false;
       }
       // In case of king moves under check we have to remove king so as to catch
@@ -652,15 +651,18 @@ bool Position::gives_check(Move m) const {
   case PROMOTION:
       return attacks_bb(promotion_type(m), to, pieces() ^ from) & square<KING>(~sideToMove);
 
-  // The double-pushed pawn blocked a check? En Passant will remove the blocker.
+  // En passant capture with check? We have already handled the case
-  // The only discovery check that wasn't handle is through capsq and fromsq
+  // of direct checks and ordinary discovered check, so the only case we
-  // So the King must be in the same rank as fromsq to consider this possibility.
+  // need to handle is the unusual case of a discovered check through
-  // st->previous->blockersForKing consider capsq as empty.
+  // the captured pawn.
   case EN_PASSANT:
-      return st->previous->checkersBB
+  {
-          || (   rank_of(square<KING>(~sideToMove)) == rank_of(from)
+      Square capsq = make_square(file_of(to), rank_of(from));
-              && st->previous->blockersForKing[~sideToMove] & from);
+      Bitboard b = (pieces() ^ from ^ capsq) | to;
 
+      return  (attacks_bb<  ROOK>(square<KING>(~sideToMove), b) & pieces(sideToMove, QUEEN, ROOK))
+            | (attacks_bb<BISHOP>(square<KING>(~sideToMove), b) & pieces(sideToMove, QUEEN, BISHOP));
+  }
   default: //CASTLING
   {
       // Castling is encoded as 'king captures the rook'
@@ -700,8 +702,8 @@ void Position::do_move(Move m, StateInfo& newSt, bool givesCheck) {
   ++st->pliesFromNull;
 
   // Used by NNUE
-  st->accumulator.state[WHITE] = Eval::NNUE::EMPTY;
+  st->accumulator.computed[WHITE] = false;
-  st->accumulator.state[BLACK] = Eval::NNUE::EMPTY;
+  st->accumulator.computed[BLACK] = false;
   auto& dp = st->dirtyPiece;
   dp.dirty_num = 1;
 
@@ -986,7 +988,7 @@ void Position::do_castling(Color us, Square from, Square& to, Square& rfrom, Squ
 }
 
 
-/// Position::do(undo)_null_move() is used to do(undo) a "null move": it flips
+/// Position::do_null_move() is used to do a "null move": it flips
 /// the side to move without executing any move on the board.
 
 void Position::do_null_move(StateInfo& newSt) {
@@ -1001,8 +1003,8 @@ void Position::do_null_move(StateInfo& newSt) {
 
   st->dirtyPiece.dirty_num = 0;
   st->dirtyPiece.piece[0] = NO_PIECE; // Avoid checks in UpdateAccumulator()
-  st->accumulator.state[WHITE] = Eval::NNUE::EMPTY;
+  st->accumulator.computed[WHITE] = false;
-  st->accumulator.state[BLACK] = Eval::NNUE::EMPTY;
+  st->accumulator.computed[BLACK] = false;
 
   if (st->epSquare != SQ_NONE)
   {
@@ -1011,9 +1013,9 @@ void Position::do_null_move(StateInfo& newSt) {
   }
 
   st->key ^= Zobrist::side;
+  ++st->rule50;
   prefetch(TT.first_entry(key()));
 
-  ++st->rule50;
   st->pliesFromNull = 0;
 
   sideToMove = ~sideToMove;
@@ -1025,6 +1027,9 @@ void Position::do_null_move(StateInfo& newSt) {
   assert(pos_is_ok());
 }
 
+
+/// Position::undo_null_move() must be used to undo a "null move"
+
 void Position::undo_null_move() {
 
   assert(!checkers());
@@ -1075,8 +1080,9 @@ bool Position::see_ge(Move m, Value threshold) const {
   if (swap <= 0)
       return true;
 
+  assert(color_of(piece_on(from)) == sideToMove);
   Bitboard occupied = pieces() ^ from ^ to;
-  Color stm = color_of(piece_on(from));
+  Color stm = sideToMove;
   Bitboard attackers = attackers_to(to, occupied);
   Bitboard stmAttackers, bb;
   int res = 1;
@@ -1090,8 +1096,8 @@ bool Position::see_ge(Move m, Value threshold) const {
       if (!(stmAttackers = attackers & pieces(stm)))
           break;
 
-      // Don't allow pinned pieces to attack (except the king) as long as
+      // Don't allow pinned pieces to attack as long as there are
-      // there are pinners on their original square.
+      // pinners on their original square.
       if (pinners(~stm) & occupied)
           stmAttackers &= ~blockers_for_king(stm);
 
@@ -1107,7 +1113,7 @@ bool Position::see_ge(Move m, Value threshold) const {
           if ((swap = PawnValueMg - swap) < res)
               break;
 
-          occupied ^= lsb(bb);
+          occupied ^= least_significant_square_bb(bb);
           attackers |= attacks_bb<BISHOP>(to, occupied) & pieces(BISHOP, QUEEN);
       }
 
@@ -1116,7 +1122,7 @@ bool Position::see_ge(Move m, Value threshold) const {
           if ((swap = KnightValueMg - swap) < res)
               break;
 
-          occupied ^= lsb(bb);
+          occupied ^= least_significant_square_bb(bb);
       }
 
       else if ((bb = stmAttackers & pieces(BISHOP)))
@@ -1124,7 +1130,7 @@ bool Position::see_ge(Move m, Value threshold) const {
           if ((swap = BishopValueMg - swap) < res)
               break;
 
-          occupied ^= lsb(bb);
+          occupied ^= least_significant_square_bb(bb);
           attackers |= attacks_bb<BISHOP>(to, occupied) & pieces(BISHOP, QUEEN);
       }
 
@@ -1133,7 +1139,7 @@ bool Position::see_ge(Move m, Value threshold) const {
           if ((swap = RookValueMg - swap) < res)
               break;
 
-          occupied ^= lsb(bb);
+          occupied ^= least_significant_square_bb(bb);
           attackers |= attacks_bb<ROOK>(to, occupied) & pieces(ROOK, QUEEN);
       }
 
@@ -1142,7 +1148,7 @@ bool Position::see_ge(Move m, Value threshold) const {
           if ((swap = QueenValueMg - swap) < res)
               break;
 
-          occupied ^= lsb(bb);
+          occupied ^= least_significant_square_bb(bb);
           attackers |=  (attacks_bb<BISHOP>(to, occupied) & pieces(BISHOP, QUEEN))
                       | (attacks_bb<ROOK  >(to, occupied) & pieces(ROOK  , QUEEN));
       }
@@ -1216,7 +1222,7 @@ bool Position::has_game_cycle(int ply) const {
           Square s1 = from_sq(move);
           Square s2 = to_sq(move);
 
-          if (!(between_bb(s1, s2) & pieces()))
+          if (!((between_bb(s1, s2) ^ s2) & pieces()))
           {
               if (ply > i)
                   return true;
@@ -1313,7 +1319,7 @@ bool Position::pos_is_ok() const {
               assert(0 && "pos_is_ok: Bitboards");
 
   StateInfo si = *st;
-  ASSERT_ALIGNED(&si, Eval::NNUE::kCacheLineSize);
+  ASSERT_ALIGNED(&si, Eval::NNUE::CacheLineSize);
 
   set_state(&si);
   if (std::memcmp(&si, st, sizeof(StateInfo)))
@@ -1338,3 +1344,5 @@ bool Position::pos_is_ok() const {
 
   return true;
 }
+
+} // namespace Stockfish

src/position.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -31,6 +31,7 @@
 
 #include "nnue/nnue_accumulator.h"
 
+namespace Stockfish {
 
 /// StateInfo struct stores information needed to restore a Position object to
 /// its previous state when we retract a move. Whenever a move is made on the
@@ -50,11 +51,11 @@ struct StateInfo {
   // Not copied when making a move (will be recomputed anyhow)
   Key        key;
   Bitboard   checkersBB;
-  Piece      capturedPiece;
   StateInfo* previous;
   Bitboard   blockersForKing[COLOR_NB];
   Bitboard   pinners[COLOR_NB];
   Bitboard   checkSquares[PIECE_TYPE_NB];
+  Piece      capturedPiece;
   int        repetition;
 
   // Used by NNUE
@@ -87,7 +88,7 @@ public:
   // FEN string input/output
   Position& set(const std::string& fenStr, bool isChess960, StateInfo* si, Thread* th);
   Position& set(const std::string& code, Color c, StateInfo* si);
-  const std::string fen() const;
+  std::string fen() const;
 
   // Position representation
   Bitboard pieces(PieceType pt) const;
@@ -114,7 +115,6 @@ public:
   Bitboard blockers_for_king(Color c) const;
   Bitboard check_squares(PieceType pt) const;
   Bitboard pinners(Color c) const;
-  bool is_discovered_check_on_king(Color c, Move m) const;
 
   // Attacks to/from a given square
   Bitboard attackers_to(Square s) const;
@@ -127,7 +127,6 @@ public:
   bool capture(Move m) const;
   bool capture_or_promotion(Move m) const;
   bool gives_check(Move m) const;
-  bool advanced_pawn_push(Move m) const;
   Piece moved_piece(Move m) const;
   Piece captured_piece() const;
 
@@ -172,6 +171,9 @@ public:
   // Used by NNUE
   StateInfo* state() const;
 
+  void put_piece(Piece pc, Square s);
+  void remove_piece(Square s);
+
 private:
   // Initialization helpers (used while setting up a position)
   void set_castling_right(Color c, Square rfrom);
@@ -179,8 +181,6 @@ private:
   void set_check_info(StateInfo* si) const;
 
   // Other helpers
-  void put_piece(Piece pc, Square s);
-  void remove_piece(Square s);
   void move_piece(Square from, Square to);
   template<bool Do>
   void do_castling(Color us, Square from, Square& to, Square& rfrom, Square& rto);
@@ -193,11 +193,11 @@ private:
   int castlingRightsMask[SQUARE_NB];
   Square castlingRookSquare[CASTLING_RIGHT_NB];
   Bitboard castlingPath[CASTLING_RIGHT_NB];
+  Thread* thisThread;
+  StateInfo* st;
   int gamePly;
   Color sideToMove;
   Score psq;
-  Thread* thisThread;
-  StateInfo* st;
   bool chess960;
 };
 
@@ -301,19 +301,10 @@ inline Bitboard Position::check_squares(PieceType pt) const {
   return st->checkSquares[pt];
 }
 
-inline bool Position::is_discovered_check_on_king(Color c, Move m) const {
-  return st->blockersForKing[c] & from_sq(m);
-}
-
 inline bool Position::pawn_passed(Color c, Square s) const {
   return !(pieces(~c, PAWN) & passed_pawn_span(c, s));
 }
 
-inline bool Position::advanced_pawn_push(Move m) const {
-  return   type_of(moved_piece(m)) == PAWN
-        && relative_rank(sideToMove, to_sq(m)) > RANK_5;
-}
-
 inline int Position::pawns_on_same_color_squares(Color c, Square s) const {
   return popcount(pieces(c, PAWN) & ((DarkSquares & s) ? DarkSquares : ~DarkSquares));
 }
@@ -396,7 +387,7 @@ inline void Position::remove_piece(Square s) {
   byTypeBB[ALL_PIECES] ^= s;
   byTypeBB[type_of(pc)] ^= s;
   byColorBB[color_of(pc)] ^= s;
-  /* board[s] = NO_PIECE;  Not needed, overwritten by the capturing one */
+  board[s] = NO_PIECE;
   pieceCount[pc]--;
   pieceCount[make_piece(color_of(pc), ALL_PIECES)]--;
   psq -= PSQT::psq[pc][s];
@@ -423,4 +414,6 @@ inline StateInfo* Position::state() const {
   return st;
 }
 
+} // namespace Stockfish
+
 #endif // #ifndef POSITION_H_INCLUDED

src/psqt.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -24,6 +24,7 @@
 #include "bitboard.h"
 #include "types.h"
 
+namespace Stockfish {
 
 namespace
 {
@@ -126,3 +127,5 @@ void init() {
 }
 
 } // namespace PSQT
+
+} // namespace Stockfish

src/psqt.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -24,7 +24,7 @@
 #include "types.h"
 
 
-namespace PSQT
+namespace Stockfish::PSQT
 {
 
 extern Score psq[PIECE_NB][SQUARE_NB];
@@ -32,7 +32,7 @@ extern Score psq[PIECE_NB][SQUARE_NB];
 // Fill psqt array from a set of internally linked parameters
 extern void init();
 
-} // namespace PSQT
+} // namespace Stockfish::PSQT
 
 
 #endif // PSQT_H_INCLUDED

src/search.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -25,6 +25,8 @@
 #include "movepick.h"
 #include "types.h"
 
+namespace Stockfish {
+
 class Position;
 
 namespace Search {
@@ -45,11 +47,13 @@ struct Stack {
   Move excludedMove;
   Move killers[2];
   Value staticEval;
+  Depth depth;
   int statScore;
   int moveCount;
   bool inCheck;
   bool ttPv;
   bool ttHit;
+  int doubleExtensions;
 };
 
 
@@ -69,6 +73,7 @@ struct RootMove {
 
   Value score = -VALUE_INFINITE;
   Value previousScore = -VALUE_INFINITE;
+  Value averageScore = -VALUE_INFINITE;
   int selDepth = 0;
   int tbRank = 0;
   Value tbScore;
@@ -106,4 +111,6 @@ void clear();
 
 } // namespace Search
 
+} // namespace Stockfish
+
 #endif // #ifndef SEARCH_H_INCLUDED

src/simd.h

@@ -0,0 +1,387 @@
+/*
+  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
+
+  Stockfish is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  Stockfish is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef STOCKFISH_SIMD_H_INCLUDED
+#define STOCKFISH_SIMD_H_INCLUDED
+
+#if defined(USE_AVX2)
+# include <immintrin.h>
+
+#elif defined(USE_SSE41)
+# include <smmintrin.h>
+
+#elif defined(USE_SSSE3)
+# include <tmmintrin.h>
+
+#elif defined(USE_SSE2)
+# include <emmintrin.h>
+
+#elif defined(USE_MMX)
+# include <mmintrin.h>
+
+#elif defined(USE_NEON)
+# include <arm_neon.h>
+#endif
+
+// The inline asm is only safe for GCC, where it is necessary to get good codegen.
+// See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101693
+// Clang does fine without it.
+// Play around here: https://godbolt.org/z/7EWqrYq51
+#if (defined(__GNUC__) && !defined(__clang__) && !defined(__INTEL_COMPILER))
+#define USE_INLINE_ASM
+#endif
+
+// Use either the AVX512 or AVX-VNNI version of the VNNI instructions.
+#if defined(USE_AVXVNNI)
+#define VNNI_PREFIX "%{vex%} "
+#else
+#define VNNI_PREFIX ""
+#endif
+
+namespace Stockfish::Simd {
+
+#if defined (USE_AVX512)
+
+    [[maybe_unused]] static int m512_hadd(__m512i sum, int bias) {
+      return _mm512_reduce_add_epi32(sum) + bias;
+    }
+
+    /*
+      Parameters:
+        sum0 = [zmm0.i128[0], zmm0.i128[1], zmm0.i128[2], zmm0.i128[3]]
+        sum1 = [zmm1.i128[0], zmm1.i128[1], zmm1.i128[2], zmm1.i128[3]]
+        sum2 = [zmm2.i128[0], zmm2.i128[1], zmm2.i128[2], zmm2.i128[3]]
+        sum3 = [zmm3.i128[0], zmm3.i128[1], zmm3.i128[2], zmm3.i128[3]]
+
+      Returns:
+        ret = [
+          reduce_add_epi32(zmm0.i128[0]), reduce_add_epi32(zmm1.i128[0]), reduce_add_epi32(zmm2.i128[0]), reduce_add_epi32(zmm3.i128[0]),
+          reduce_add_epi32(zmm0.i128[1]), reduce_add_epi32(zmm1.i128[1]), reduce_add_epi32(zmm2.i128[1]), reduce_add_epi32(zmm3.i128[1]),
+          reduce_add_epi32(zmm0.i128[2]), reduce_add_epi32(zmm1.i128[2]), reduce_add_epi32(zmm2.i128[2]), reduce_add_epi32(zmm3.i128[2]),
+          reduce_add_epi32(zmm0.i128[3]), reduce_add_epi32(zmm1.i128[3]), reduce_add_epi32(zmm2.i128[3]), reduce_add_epi32(zmm3.i128[3])
+        ]
+    */
+    [[maybe_unused]] static __m512i m512_hadd128x16_interleave(
+        __m512i sum0, __m512i sum1, __m512i sum2, __m512i sum3) {
+
+      __m512i sum01a = _mm512_unpacklo_epi32(sum0, sum1);
+      __m512i sum01b = _mm512_unpackhi_epi32(sum0, sum1);
+
+      __m512i sum23a = _mm512_unpacklo_epi32(sum2, sum3);
+      __m512i sum23b = _mm512_unpackhi_epi32(sum2, sum3);
+
+      __m512i sum01 = _mm512_add_epi32(sum01a, sum01b);
+      __m512i sum23 = _mm512_add_epi32(sum23a, sum23b);
+
+      __m512i sum0123a = _mm512_unpacklo_epi64(sum01, sum23);
+      __m512i sum0123b = _mm512_unpackhi_epi64(sum01, sum23);
+
+      return _mm512_add_epi32(sum0123a, sum0123b);
+    }
+
+    [[maybe_unused]] static __m128i m512_haddx4(
+        __m512i sum0, __m512i sum1, __m512i sum2, __m512i sum3,
+        __m128i bias) {
+
+      __m512i sum = m512_hadd128x16_interleave(sum0, sum1, sum2, sum3);
+
+      __m256i sum256lo = _mm512_castsi512_si256(sum);
+      __m256i sum256hi = _mm512_extracti64x4_epi64(sum, 1);
+
+      sum256lo = _mm256_add_epi32(sum256lo, sum256hi);
+
+      __m128i sum128lo = _mm256_castsi256_si128(sum256lo);
+      __m128i sum128hi = _mm256_extracti128_si256(sum256lo, 1);
+
+      return _mm_add_epi32(_mm_add_epi32(sum128lo, sum128hi), bias);
+    }
+
+    [[maybe_unused]] static void m512_add_dpbusd_epi32(
+        __m512i& acc,
+        __m512i a,
+        __m512i b) {
+
+# if defined (USE_VNNI)
+#   if defined (USE_INLINE_ASM)
+      asm(
+        "vpdpbusd %[b], %[a], %[acc]\n\t"
+        : [acc]"+v"(acc)
+        : [a]"v"(a), [b]"vm"(b)
+      );
+#   else
+      acc = _mm512_dpbusd_epi32(acc, a, b);
+#   endif
+# else
+#   if defined (USE_INLINE_ASM)
+      __m512i tmp = _mm512_maddubs_epi16(a, b);
+      asm(
+          "vpmaddwd    %[tmp], %[ones], %[tmp]\n\t"
+          "vpaddd      %[acc], %[tmp], %[acc]\n\t"
+          : [acc]"+v"(acc), [tmp]"+&v"(tmp)
+          : [ones]"v"(_mm512_set1_epi16(1))
+      );
+#   else
+      __m512i product0 = _mm512_maddubs_epi16(a, b);
+      product0 = _mm512_madd_epi16(product0, _mm512_set1_epi16(1));
+      acc = _mm512_add_epi32(acc, product0);
+#   endif
+# endif
+    }
+
+    [[maybe_unused]] static void m512_add_dpbusd_epi32x2(
+        __m512i& acc,
+        __m512i a0, __m512i b0,
+        __m512i a1, __m512i b1) {
+
+# if defined (USE_VNNI)
+#   if defined (USE_INLINE_ASM)
+      asm(
+        "vpdpbusd %[b0], %[a0], %[acc]\n\t"
+        "vpdpbusd %[b1], %[a1], %[acc]\n\t"
+        : [acc]"+v"(acc)
+        : [a0]"v"(a0), [b0]"vm"(b0), [a1]"v"(a1), [b1]"vm"(b1)
+      );
+#   else
+      acc = _mm512_dpbusd_epi32(acc, a0, b0);
+      acc = _mm512_dpbusd_epi32(acc, a1, b1);
+#   endif
+# else
+#   if defined (USE_INLINE_ASM)
+      __m512i tmp0 = _mm512_maddubs_epi16(a0, b0);
+      __m512i tmp1 = _mm512_maddubs_epi16(a1, b1);
+      asm(
+          "vpaddsw     %[tmp0], %[tmp1], %[tmp0]\n\t"
+          "vpmaddwd    %[tmp0], %[ones], %[tmp0]\n\t"
+          "vpaddd      %[acc], %[tmp0], %[acc]\n\t"
+          : [acc]"+v"(acc), [tmp0]"+&v"(tmp0)
+          : [tmp1]"v"(tmp1), [ones]"v"(_mm512_set1_epi16(1))
+      );
+#   else
+      __m512i product0 = _mm512_maddubs_epi16(a0, b0);
+      __m512i product1 = _mm512_maddubs_epi16(a1, b1);
+      product0 = _mm512_adds_epi16(product0, product1);
+      product0 = _mm512_madd_epi16(product0, _mm512_set1_epi16(1));
+      acc = _mm512_add_epi32(acc, product0);
+#   endif
+# endif
+    }
+
+#endif
+
+#if defined (USE_AVX2)
+
+    [[maybe_unused]] static int m256_hadd(__m256i sum, int bias) {
+      __m128i sum128 = _mm_add_epi32(_mm256_castsi256_si128(sum), _mm256_extracti128_si256(sum, 1));
+      sum128 = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_BADC));
+      sum128 = _mm_add_epi32(sum128, _mm_shuffle_epi32(sum128, _MM_PERM_CDAB));
+      return _mm_cvtsi128_si32(sum128) + bias;
+    }
+
+    [[maybe_unused]] static __m128i m256_haddx4(
+        __m256i sum0, __m256i sum1, __m256i sum2, __m256i sum3,
+        __m128i bias) {
+
+      sum0 = _mm256_hadd_epi32(sum0, sum1);
+      sum2 = _mm256_hadd_epi32(sum2, sum3);
+
+      sum0 = _mm256_hadd_epi32(sum0, sum2);
+
+      __m128i sum128lo = _mm256_castsi256_si128(sum0);
+      __m128i sum128hi = _mm256_extracti128_si256(sum0, 1);
+
+      return _mm_add_epi32(_mm_add_epi32(sum128lo, sum128hi), bias);
+    }
+
+    [[maybe_unused]] static void m256_add_dpbusd_epi32(
+        __m256i& acc,
+        __m256i a,
+        __m256i b) {
+
+# if defined (USE_VNNI)
+#   if defined (USE_INLINE_ASM)
+      asm(
+        VNNI_PREFIX "vpdpbusd %[b], %[a], %[acc]\n\t"
+        : [acc]"+v"(acc)
+        : [a]"v"(a), [b]"vm"(b)
+      );
+#   else
+      acc = _mm256_dpbusd_epi32(acc, a, b);
+#   endif
+# else
+#   if defined (USE_INLINE_ASM)
+      __m256i tmp = _mm256_maddubs_epi16(a, b);
+      asm(
+          "vpmaddwd    %[tmp], %[ones], %[tmp]\n\t"
+          "vpaddd      %[acc], %[tmp], %[acc]\n\t"
+          : [acc]"+v"(acc), [tmp]"+&v"(tmp)
+          : [ones]"v"(_mm256_set1_epi16(1))
+      );
+#   else
+      __m256i product0 = _mm256_maddubs_epi16(a, b);
+      product0 = _mm256_madd_epi16(product0, _mm256_set1_epi16(1));
+      acc = _mm256_add_epi32(acc, product0);
+#   endif
+# endif
+    }
+
+    [[maybe_unused]] static void m256_add_dpbusd_epi32x2(
+        __m256i& acc,
+        __m256i a0, __m256i b0,
+        __m256i a1, __m256i b1) {
+
+# if defined (USE_VNNI)
+#   if defined (USE_INLINE_ASM)
+      asm(
+        VNNI_PREFIX "vpdpbusd %[b0], %[a0], %[acc]\n\t"
+        VNNI_PREFIX "vpdpbusd %[b1], %[a1], %[acc]\n\t"
+        : [acc]"+v"(acc)
+        : [a0]"v"(a0), [b0]"vm"(b0), [a1]"v"(a1), [b1]"vm"(b1)
+      );
+#   else
+      acc = _mm256_dpbusd_epi32(acc, a0, b0);
+      acc = _mm256_dpbusd_epi32(acc, a1, b1);
+#   endif
+# else
+#   if defined (USE_INLINE_ASM)
+      __m256i tmp0 = _mm256_maddubs_epi16(a0, b0);
+      __m256i tmp1 = _mm256_maddubs_epi16(a1, b1);
+      asm(
+          "vpaddsw     %[tmp0], %[tmp1], %[tmp0]\n\t"
+          "vpmaddwd    %[tmp0], %[ones], %[tmp0]\n\t"
+          "vpaddd      %[acc], %[tmp0], %[acc]\n\t"
+          : [acc]"+v"(acc), [tmp0]"+&v"(tmp0)
+          : [tmp1]"v"(tmp1), [ones]"v"(_mm256_set1_epi16(1))
+      );
+#   else
+      __m256i product0 = _mm256_maddubs_epi16(a0, b0);
+      __m256i product1 = _mm256_maddubs_epi16(a1, b1);
+      product0 = _mm256_adds_epi16(product0, product1);
+      product0 = _mm256_madd_epi16(product0, _mm256_set1_epi16(1));
+      acc = _mm256_add_epi32(acc, product0);
+#   endif
+# endif
+    }
+
+#endif
+
+#if defined (USE_SSSE3)
+
+    [[maybe_unused]] static int m128_hadd(__m128i sum, int bias) {
+      sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0x4E)); //_MM_PERM_BADC
+      sum = _mm_add_epi32(sum, _mm_shuffle_epi32(sum, 0xB1)); //_MM_PERM_CDAB
+      return _mm_cvtsi128_si32(sum) + bias;
+    }
+
+    [[maybe_unused]] static __m128i m128_haddx4(
+        __m128i sum0, __m128i sum1, __m128i sum2, __m128i sum3,
+        __m128i bias) {
+
+      sum0 = _mm_hadd_epi32(sum0, sum1);
+      sum2 = _mm_hadd_epi32(sum2, sum3);
+      sum0 = _mm_hadd_epi32(sum0, sum2);
+      return _mm_add_epi32(sum0, bias);
+    }
+
+    [[maybe_unused]] static void m128_add_dpbusd_epi32(
+        __m128i& acc,
+        __m128i a,
+        __m128i b) {
+
+#   if defined (USE_INLINE_ASM)
+      __m128i tmp = _mm_maddubs_epi16(a, b);
+      asm(
+          "pmaddwd    %[ones], %[tmp]\n\t"
+          "paddd      %[tmp], %[acc]\n\t"
+          : [acc]"+v"(acc), [tmp]"+&v"(tmp)
+          : [ones]"v"(_mm_set1_epi16(1))
+      );
+#   else
+      __m128i product0 = _mm_maddubs_epi16(a, b);
+      product0 = _mm_madd_epi16(product0, _mm_set1_epi16(1));
+      acc = _mm_add_epi32(acc, product0);
+#   endif
+    }
+
+    [[maybe_unused]] static void m128_add_dpbusd_epi32x2(
+        __m128i& acc,
+        __m128i a0, __m128i b0,
+        __m128i a1, __m128i b1) {
+
+#   if defined (USE_INLINE_ASM)
+      __m128i tmp0 = _mm_maddubs_epi16(a0, b0);
+      __m128i tmp1 = _mm_maddubs_epi16(a1, b1);
+      asm(
+          "paddsw     %[tmp1], %[tmp0]\n\t"
+          "pmaddwd    %[ones], %[tmp0]\n\t"
+          "paddd      %[tmp0], %[acc]\n\t"
+          : [acc]"+v"(acc), [tmp0]"+&v"(tmp0)
+          : [tmp1]"v"(tmp1), [ones]"v"(_mm_set1_epi16(1))
+      );
+#   else
+      __m128i product0 = _mm_maddubs_epi16(a0, b0);
+      __m128i product1 = _mm_maddubs_epi16(a1, b1);
+      product0 = _mm_adds_epi16(product0, product1);
+      product0 = _mm_madd_epi16(product0, _mm_set1_epi16(1));
+      acc = _mm_add_epi32(acc, product0);
+#   endif
+    }
+
+#endif
+
+#if defined (USE_NEON)
+
+    [[maybe_unused]] static int neon_m128_reduce_add_epi32(int32x4_t s) {
+#   if USE_NEON >= 8
+      return vaddvq_s32(s);
+#   else
+      return s[0] + s[1] + s[2] + s[3];
+#   endif
+    }
+
+    [[maybe_unused]] static int neon_m128_hadd(int32x4_t sum, int bias) {
+      return neon_m128_reduce_add_epi32(sum) + bias;
+    }
+
+    [[maybe_unused]] static int32x4_t neon_m128_haddx4(
+        int32x4_t sum0, int32x4_t sum1, int32x4_t sum2, int32x4_t sum3,
+        int32x4_t bias) {
+
+      int32x4_t hsums {
+        neon_m128_reduce_add_epi32(sum0),
+        neon_m128_reduce_add_epi32(sum1),
+        neon_m128_reduce_add_epi32(sum2),
+        neon_m128_reduce_add_epi32(sum3)
+      };
+      return vaddq_s32(hsums, bias);
+    }
+
+    [[maybe_unused]] static void neon_m128_add_dpbusd_epi32x2(
+        int32x4_t& acc,
+        int8x8_t a0, int8x8_t b0,
+        int8x8_t a1, int8x8_t b1) {
+
+      int16x8_t product = vmull_s8(a0, b0);
+      product = vmlal_s8(product, a1, b1);
+      acc = vpadalq_s16(acc, product);
+    }
+
+#endif
+
+}
+
+#endif // STOCKFISH_SIMD_H_INCLUDED

src/syzygy/tbprobe.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -50,9 +50,11 @@
 #include <windows.h>
 #endif
 
-using namespace Tablebases;
+using namespace Stockfish::Tablebases;
 
-int Tablebases::MaxCardinality;
+int Stockfish::Tablebases::MaxCardinality;
+
+namespace Stockfish {
 
 namespace {
 
@@ -103,9 +105,6 @@ template<> inline void swap_endian<uint8_t>(uint8_t&) {}
 
 template<typename T, int LE> T number(void* addr)
 {
-    static const union { uint32_t i; char c[4]; } Le = { 0x01020304 };
-    static const bool IsLittleEndian = (Le.c[0] == 4);
-
     T v;
 
     if ((uintptr_t)addr & (alignof(T) - 1)) // Unaligned pointer (very rare)
@@ -190,7 +189,8 @@ public:
         std::stringstream ss(Paths);
         std::string path;
 
-        while (std::getline(ss, path, SepChar)) {
+        while (std::getline(ss, path, SepChar))
+        {
             fname = path + "/" + f;
             std::ifstream::open(fname);
             if (is_open())
@@ -565,7 +565,8 @@ int decompress_pairs(PairsData* d, uint64_t idx) {
     int buf64Size = 64;
     Sym sym;
 
-    while (true) {
+    while (true)
+    {
         int len = 0; // This is the symbol length - d->min_sym_len
 
         // Now get the symbol length. For any symbol s64 of length l right-padded
@@ -603,8 +604,8 @@ int decompress_pairs(PairsData* d, uint64_t idx) {
     // We binary-search for our value recursively expanding into the left and
     // right child symbols until we reach a leaf node where symlen[sym] + 1 == 1
     // that will store the value we need.
-    while (d->symlen[sym]) {
+    while (d->symlen[sym])
-
+    {
         Sym left = d->btree[sym].get<LR::Left>();
 
         // If a symbol contains 36 sub-symbols (d->symlen[sym] + 1 = 36) and
@@ -709,7 +710,7 @@ Ret do_probe_table(const Position& pos, T* entry, WDLScore wdl, ProbeState* resu
 
         leadPawns = b = pos.pieces(color_of(pc), PAWN);
         do
-            squares[size++] = pop_lsb(&b) ^ flipSquares;
+            squares[size++] = pop_lsb(b) ^ flipSquares;
         while (b);
 
         leadPawnsCnt = size;
@@ -729,7 +730,7 @@ Ret do_probe_table(const Position& pos, T* entry, WDLScore wdl, ProbeState* resu
     // directly map them to the correct color and square.
     b = pos.pieces() ^ leadPawns;
     do {
-        Square s = pop_lsb(&b);
+        Square s = pop_lsb(b);
         squares[size] = s ^ flipSquares;
         pieces[size++] = Piece(pos.piece_on(s) ^ flipColor);
     } while (b);
@@ -768,7 +769,7 @@ Ret do_probe_table(const Position& pos, T* entry, WDLScore wdl, ProbeState* resu
         goto encode_remaining; // With pawns we have finished special treatments
     }
 
-    // In positions withouth pawns, we further flip the squares to ensure leading
+    // In positions without pawns, we further flip the squares to ensure leading
     // piece is below RANK_5.
     if (rank_of(squares[0]) > RANK_4)
         for (int i = 0; i < size; ++i)
@@ -811,7 +812,7 @@ Ret do_probe_table(const Position& pos, T* entry, WDLScore wdl, ProbeState* resu
     // Rs "together" in 62 * 61 / 2 ways (we divide by 2 because rooks can be
     // swapped and still get the same position.)
     //
-    // In case we have at least 3 unique pieces (inlcuded kings) we encode them
+    // In case we have at least 3 unique pieces (included kings) we encode them
     // together.
     if (entry->hasUniquePieces) {
 
@@ -826,7 +827,7 @@ Ret do_probe_table(const Position& pos, T* entry, WDLScore wdl, ProbeState* resu
                    + (squares[1] - adjust1)) * 62
                    +  squares[2] - adjust2;
 
-        // First piece is on a1-h8 diagonal, second below: map this occurence to
+        // First piece is on a1-h8 diagonal, second below: map this occurrence to
         // 6 to differentiate from the above case, rank_of() maps a1-d4 diagonal
         // to 0...3 and finally MapB1H1H7[] maps the b1-h1-h7 triangle to 0..27.
         else if (off_A1H8(squares[1]))
@@ -856,7 +857,7 @@ encode_remaining:
     idx *= d->groupIdx[0];
     Square* groupSq = squares + d->groupLen[0];
 
-    // Encode remainig pawns then pieces according to square, in ascending order
+    // Encode remaining pawns then pieces according to square, in ascending order
     bool remainingPawns = entry->hasPawns && entry->pawnCount[1];
 
     while (d->groupLen[++next])
@@ -884,7 +885,7 @@ encode_remaining:
 
 // Group together pieces that will be encoded together. The general rule is that
 // a group contains pieces of same type and color. The exception is the leading
-// group that, in case of positions withouth pawns, can be formed by 3 different
+// group that, in case of positions without pawns, can be formed by 3 different
 // pieces (default) or by the king pair when there is not a unique piece apart
 // from the kings. When there are pawns, pawns are always first in pieces[].
 //
@@ -916,7 +917,7 @@ void set_groups(T& e, PairsData* d, int order[], File f) {
     //
     // This ensures unique encoding for the whole position. The order of the
     // groups is a per-table parameter and could not follow the canonical leading
-    // pawns/pieces -> remainig pawns -> remaining pieces. In particular the
+    // pawns/pieces -> remaining pawns -> remaining pieces. In particular the
     // first group is at order[0] position and the remaining pawns, when present,
     // are at order[1] position.
     bool pp = e.hasPawns && e.pawnCount[1]; // Pawns on both sides
@@ -936,7 +937,7 @@ void set_groups(T& e, PairsData* d, int order[], File f) {
             d->groupIdx[1] = idx;
             idx *= Binomial[d->groupLen[1]][48 - d->groupLen[0]];
         }
-        else // Remainig pieces
+        else // Remaining pieces
         {
             d->groupIdx[next] = idx;
             idx *= Binomial[d->groupLen[next]][freeSquares];
@@ -946,7 +947,7 @@ void set_groups(T& e, PairsData* d, int order[], File f) {
     d->groupIdx[n] = idx;
 }
 
-// In Recursive Pairing each symbol represents a pair of childern symbols. So
+// In Recursive Pairing each symbol represents a pair of children symbols. So
 // read d->btree[] symbols data and expand each one in his left and right child
 // symbol until reaching the leafs that represent the symbol value.
 uint8_t set_symlen(PairsData* d, Sym s, std::vector<bool>& visited) {
@@ -1316,7 +1317,7 @@ void Tablebases::init(const std::string& paths) {
     for (auto p : bothOnDiagonal)
         MapKK[p.first][p.second] = code++;
 
-    // Binomial[] stores the Binomial Coefficents using Pascal rule. There
+    // Binomial[] stores the Binomial Coefficients using Pascal rule. There
     // are Binomial[k][n] ways to choose k elements from a set of n elements.
     Binomial[0][0] = 1;
 
@@ -1336,7 +1337,7 @@ void Tablebases::init(const std::string& paths) {
     for (int leadPawnsCnt = 1; leadPawnsCnt <= 5; ++leadPawnsCnt)
         for (File f = FILE_A; f <= FILE_D; ++f)
         {
-            // Restart the index at every file because TB table is splitted
+            // Restart the index at every file because TB table is split
             // by file, so we can reuse the same index for different files.
             int idx = 0;
 
@@ -1535,6 +1536,14 @@ bool Tablebases::root_probe(Position& pos, Search::RootMoves& rootMoves) {
             WDLScore wdl = -probe_wdl(pos, &result);
             dtz = dtz_before_zeroing(wdl);
         }
+        else if (pos.is_draw(1))
+        {
+            // In case a root move leads to a draw by repetition or
+            // 50-move rule, we set dtz to zero. Note: since we are
+            // only 1 ply from the root, this must be a true 3-fold
+            // repetition inside the game history.
+            dtz = 0;
+        }
         else
         {
             // Otherwise, take dtz for the new position and correct by 1 ply
@@ -1585,6 +1594,7 @@ bool Tablebases::root_probe_wdl(Position& pos, Search::RootMoves& rootMoves) {
 
     ProbeState result;
     StateInfo st;
+    WDLScore wdl;
 
     bool rule50 = Options["Syzygy50MoveRule"];
 
@@ -1593,7 +1603,10 @@ bool Tablebases::root_probe_wdl(Position& pos, Search::RootMoves& rootMoves) {
     {
         pos.do_move(m.pv[0], st);
 
-        WDLScore wdl = -probe_wdl(pos, &result);
+        if (pos.is_draw(1))
+            wdl = WDLDraw;
+        else
+            wdl = -probe_wdl(pos, &result);
 
         pos.undo_move(m.pv[0]);
 
@@ -1610,3 +1623,5 @@ bool Tablebases::root_probe_wdl(Position& pos, Search::RootMoves& rootMoves) {
 
     return true;
 }
+
+} // namespace Stockfish

src/syzygy/tbprobe.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -23,7 +23,7 @@
 
 #include "../search.h"
 
-namespace Tablebases {
+namespace Stockfish::Tablebases {
 
 enum WDLScore {
     WDLLoss        = -2, // Loss
@@ -38,7 +38,7 @@ enum WDLScore {
 // Possible states after a probing operation
 enum ProbeState {
     FAIL              =  0, // Probe failed (missing file table)
-    OK                =  1, // Probe succesful
+    OK                =  1, // Probe successful
     CHANGE_STM        = -1, // DTZ should check the other side
     ZEROING_BEST_MOVE =  2  // Best move zeroes DTZ (capture or pawn move)
 };
@@ -73,6 +73,6 @@ inline std::ostream& operator<<(std::ostream& os, const ProbeState v) {
     return os;
 }
 
-}
+} // namespace Stockfish::Tablebases
 
 #endif

src/thread.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -26,6 +26,8 @@
 #include "syzygy/tbprobe.h"
 #include "tt.h"
 
+namespace Stockfish {
+
 ThreadPool Threads; // Global object
 
 
@@ -57,7 +59,6 @@ void Thread::clear() {
 
   counterMoves.fill(MOVE_NONE);
   mainHistory.fill(0);
-  lowPlyHistory.fill(0);
   captureHistory.fill(0);
 
   for (bool inCheck : { false, true })
@@ -65,7 +66,7 @@ void Thread::clear() {
       {
           for (auto& to : continuationHistory[inCheck][c])
                 for (auto& h : to)
-                      h->fill(0);
+                      h->fill(-71);
           continuationHistory[inCheck][c][NO_PIECE][0]->fill(Search::CounterMovePruneThreshold - 1);
       }
 }
@@ -126,14 +127,16 @@ void Thread::idle_loop() {
 
 void ThreadPool::set(size_t requested) {
 
-  if (size() > 0) { // destroy any existing thread(s)
+  if (size() > 0)   // destroy any existing thread(s)
+  {
       main()->wait_for_search_finished();
 
       while (size() > 0)
           delete back(), pop_back();
   }
 
-  if (requested > 0) { // create new thread(s)
+  if (requested > 0)   // create new thread(s)
+  {
       push_back(new MainThread(0));
 
       while (size() < requested)
@@ -158,6 +161,7 @@ void ThreadPool::clear() {
 
   main()->callsCnt = 0;
   main()->bestPreviousScore = VALUE_INFINITE;
+  main()->bestPreviousAverageScore = VALUE_INFINITE;
   main()->previousTimeReduction = 1.0;
 }
 
@@ -258,3 +262,5 @@ void ThreadPool::wait_for_search_finished() const {
         if (th != front())
             th->wait_for_search_finished();
 }
+
+} // namespace Stockfish

src/thread.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -32,6 +32,7 @@
 #include "search.h"
 #include "thread_win32_osx.h"
 
+namespace Stockfish {
 
 /// Thread class keeps together all the thread-related stuff. We use
 /// per-thread pawn and material hash tables so that once we get a
@@ -54,26 +55,27 @@ public:
   void idle_loop();
   void start_searching();
   void wait_for_search_finished();
+  size_t id() const { return idx; }
 
   Pawns::Table pawnsTable;
   Material::Table materialTable;
   size_t pvIdx, pvLast;
-  uint64_t ttHitAverage;
+  RunningAverage complexityAverage;
+  std::atomic<uint64_t> nodes, tbHits, bestMoveChanges;
   int selDepth, nmpMinPly;
   Color nmpColor;
-  std::atomic<uint64_t> nodes, tbHits, bestMoveChanges;
+  Value bestValue, optimism[COLOR_NB];
 
   Position rootPos;
   StateInfo rootState;
   Search::RootMoves rootMoves;
   Depth rootDepth, completedDepth;
+  Value rootDelta;
   CounterMoveHistory counterMoves;
   ButterflyHistory mainHistory;
-  LowPlyHistory lowPlyHistory;
   CapturePieceToHistory captureHistory;
   ContinuationHistory continuationHistory[2][2];
-  Score contempt;
+  Score trend;
-  int failedHighCnt;
 };
 
 
@@ -88,6 +90,7 @@ struct MainThread : public Thread {
 
   double previousTimeReduction;
   Value bestPreviousScore;
+  Value bestPreviousAverageScore;
   Value iterValue[4];
   int callsCnt;
   bool stopOnPonderhit;
@@ -128,4 +131,6 @@ private:
 
 extern ThreadPool Threads;
 
+} // namespace Stockfish
+
 #endif // #ifndef THREAD_H_INCLUDED

src/thread_win32_osx.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -31,6 +31,8 @@
 
 #include <pthread.h>
 
+namespace Stockfish {
+
 static const size_t TH_STACK_SIZE = 8 * 1024 * 1024;
 
 template <class T, class P = std::pair<T*, void(T::*)()>>
@@ -57,10 +59,16 @@ public:
   void join() { pthread_join(thread, NULL); }
 };
 
+} // namespace Stockfish
+
 #else // Default case: use STL classes
 
+namespace Stockfish {
+
 typedef std::thread NativeThread;
 
+} // namespace Stockfish
+
 #endif
 
 #endif // #ifndef THREAD_WIN32_OSX_H_INCLUDED

src/timeman.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -24,6 +24,8 @@
 #include "timeman.h"
 #include "uci.h"
 
+namespace Stockfish {
+
 TimeManagement Time; // Our global time management object
 
 
@@ -66,6 +68,9 @@ void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) {
   TimePoint timeLeft =  std::max(TimePoint(1),
       limits.time[us] + limits.inc[us] * (mtg - 1) - moveOverhead * (2 + mtg));
 
+  // Use extra time with larger increments
+  double optExtra = std::clamp(1.0 + 12.0 * limits.inc[us] / limits.time[us], 1.0, 1.12);
+
   // A user may scale time usage by setting UCI option "Slow Mover"
   // Default is 100 and changing this value will probably lose elo.
   timeLeft = slowMover * timeLeft / 100;
@@ -76,15 +81,16 @@ void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) {
   if (limits.movestogo == 0)
   {
       optScale = std::min(0.0084 + std::pow(ply + 3.0, 0.5) * 0.0042,
-                           0.2 * limits.time[us] / double(timeLeft));
+                           0.2 * limits.time[us] / double(timeLeft))
+                 * optExtra;
       maxScale = std::min(7.0, 4.0 + ply / 12.0);
   }
 
   // x moves in y seconds (+ z increment)
   else
   {
-      optScale = std::min((0.8 + ply / 128.0) / mtg,
+      optScale = std::min((0.88 + ply / 116.4) / mtg,
-                            0.8 * limits.time[us] / double(timeLeft));
+                            0.88 * limits.time[us] / double(timeLeft));
       maxScale = std::min(6.3, 1.5 + 0.11 * mtg);
   }
 
@@ -95,3 +101,5 @@ void TimeManagement::init(Search::LimitsType& limits, Color us, int ply) {
   if (Options["Ponder"])
       optimumTime += optimumTime / 4;
 }
+
+} // namespace Stockfish

src/timeman.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -23,6 +23,8 @@
 #include "search.h"
 #include "thread.h"
 
+namespace Stockfish {
+
 /// The TimeManagement class computes the optimal time to think depending on
 /// the maximum available time, the game move number and other parameters.
 
@@ -44,4 +46,6 @@ private:
 
 extern TimeManagement Time;
 
+} // namespace Stockfish
+
 #endif // #ifndef TIMEMAN_H_INCLUDED

src/tt.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -26,6 +26,8 @@
 #include "tt.h"
 #include "uci.h"
 
+namespace Stockfish {
+
 TranspositionTable TT; // Our global transposition table
 
 /// TTEntry::save() populates the TTEntry with a new node's data, possibly
@@ -38,9 +40,9 @@ void TTEntry::save(Key k, Value v, bool pv, Bound b, Depth d, Move m, Value ev)
       move16 = (uint16_t)m;
 
   // Overwrite less valuable entries (cheapest checks first)
-  if (b == BOUND_EXACT
+  if (   b == BOUND_EXACT
       || (uint16_t)k != key16
-      || d - DEPTH_OFFSET > depth8 - 4)
+      || d - DEPTH_OFFSET + 2 * pv > depth8 - 4)
   {
       assert(d > DEPTH_OFFSET);
       assert(d < 256 + DEPTH_OFFSET);
@@ -156,3 +158,5 @@ int TranspositionTable::hashfull() const {
 
   return cnt / ClusterSize;
 }
+
+} // namespace Stockfish

src/tt.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -22,6 +22,8 @@
 #include "misc.h"
 #include "types.h"
 
+namespace Stockfish {
+
 /// TTEntry struct is the 10 bytes transposition table entry, defined as below:
 ///
 /// key        16 bit
@@ -100,4 +102,6 @@ private:
 
 extern TranspositionTable TT;
 
+} // namespace Stockfish
+
 #endif // #ifndef TT_H_INCLUDED

src/tune.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -26,9 +26,10 @@
 
 using std::string;
 
+namespace Stockfish {
+
 bool Tune::update_on_last;
 const UCI::Option* LastOption = nullptr;
-BoolConditions Conditions;
 static std::map<std::string, int> TuneResults;
 
 string Tune::next(string& names, bool pop) {
@@ -108,23 +109,7 @@ template<> void Tune::Entry<Score>::read_option() {
 template<> void Tune::Entry<Tune::PostUpdate>::init_option() {}
 template<> void Tune::Entry<Tune::PostUpdate>::read_option() { value(); }
 
-
+} // namespace Stockfish
-// Set binary conditions according to a probability that depends
-// on the corresponding parameter value.
-
-void BoolConditions::set() {
-
-  static PRNG rng(now());
-  static bool startup = true; // To workaround fishtest bench
-
-  for (size_t i = 0; i < binary.size(); i++)
-      binary[i] = !startup && (values[i] + int(rng.rand<unsigned>() % variance) > threshold);
-
-  startup = false;
-
-  for (size_t i = 0; i < binary.size(); i++)
-      sync_cout << binary[i] << sync_endl;
-}
 
 
 // Init options with tuning session results instead of default values. Useful to
@@ -138,7 +123,11 @@ void BoolConditions::set() {
 
 #include <cmath>
 
+namespace Stockfish {
+
 void Tune::read_results() {
 
   /* ...insert your values here... */
 }
+
+} // namespace Stockfish

src/tune.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -24,6 +24,8 @@
 #include <type_traits>
 #include <vector>
 
+namespace Stockfish {
+
 typedef std::pair<int, int> Range; // Option's min-max values
 typedef Range (RangeFun) (int);
 
@@ -44,27 +46,6 @@ struct SetRange {
 #define SetDefaultRange SetRange(default_range)
 
 
-/// BoolConditions struct is used to tune boolean conditions in the
-/// code by toggling them on/off according to a probability that
-/// depends on the value of a tuned integer parameter: for high
-/// values of the parameter condition is always disabled, for low
-/// values is always enabled, otherwise it is enabled with a given
-/// probability that depnends on the parameter under tuning.
-
-struct BoolConditions {
-  void init(size_t size) { values.resize(size, defaultValue), binary.resize(size, 0); }
-  void set();
-
-  std::vector<int> binary, values;
-  int defaultValue = 465, variance = 40, threshold = 500;
-  SetRange range = SetRange(0, 1000);
-};
-
-extern BoolConditions Conditions;
-
-inline void set_conditions() { Conditions.set(); }
-
-
 /// Tune class implements the 'magic' code that makes the setup of a fishtest
 /// tuning session as easy as it can be. Mainly you have just to remove const
 /// qualifiers from the variables you want to tune and flag them for tuning, so
@@ -103,7 +84,7 @@ class Tune {
 
   static Tune& instance() { static Tune t; return t; } // Singleton
 
-  // Use polymorphism to accomodate Entry of different types in the same vector
+  // Use polymorphism to accommodate Entry of different types in the same vector
   struct EntryBase {
     virtual ~EntryBase() = default;
     virtual void init_option() = 0;
@@ -157,14 +138,6 @@ class Tune {
     return add(value, (next(names), std::move(names)), args...);
   }
 
-  // Template specialization for BoolConditions
-  template<typename... Args>
-  int add(const SetRange& range, std::string&& names, BoolConditions& cond, Args&&... args) {
-    for (size_t size = cond.values.size(), i = 0; i < size; i++)
-        add(cond.range, next(names, i == size - 1) + "_" + std::to_string(i), cond.values[i]);
-    return add(range, std::move(names), args...);
-  }
-
   std::vector<std::unique_ptr<EntryBase>> list;
 
 public:
@@ -185,9 +158,6 @@ public:
 
 #define UPDATE_ON_LAST() bool UNIQUE(p, __LINE__) = Tune::update_on_last = true
 
-// Some macro to tune toggling of boolean conditions
+} // namespace Stockfish
-#define CONDITION(x) (Conditions.binary[__COUNTER__] || (x))
-#define TUNE_CONDITIONS() int UNIQUE(c, __LINE__) = (Conditions.init(__COUNTER__), 0); \
-                          TUNE(Conditions, set_conditions)
 
 #endif // #ifndef TUNE_H_INCLUDED

src/types.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -83,6 +83,8 @@
 #  define pext(b, m) 0
 #endif
 
+namespace Stockfish {
+
 #ifdef USE_POPCNT
 constexpr bool HasPopCnt = true;
 #else
@@ -189,7 +191,6 @@ enum Value : int {
   BishopValueMg = 825,   BishopValueEg = 915,
   RookValueMg   = 1276,  RookValueEg   = 1380,
   QueenValueMg  = 2538,  QueenValueEg  = 2682,
-  Tempo = 28,
 
   MidgameLimit  = 15258, EndgameLimit  = 3915
 };
@@ -466,10 +467,6 @@ constexpr Move make_move(Square from, Square to) {
   return Move((from << 6) + to);
 }
 
-constexpr Move reverse_move(Move m) {
-  return make_move(to_sq(m), from_sq(m));
-}
-
 template<MoveType T>
 constexpr Move make(Square from, Square to, PieceType pt = KNIGHT) {
   return Move(T + ((pt - KNIGHT) << 12) + (from << 6) + to);
@@ -484,6 +481,8 @@ constexpr Key make_key(uint64_t seed) {
   return seed * 6364136223846793005ULL + 1442695040888963407ULL;
 }
 
+} // namespace Stockfish
+
 #endif // #ifndef TYPES_H_INCLUDED
 
 #include "tune.h" // Global visibility to tuning setup

src/uci.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -34,6 +34,8 @@
 
 using namespace std;
 
+namespace Stockfish {
+
 extern vector<string> setup_bench(const Position&, istream&);
 
 namespace {
@@ -205,13 +207,13 @@ namespace {
      // Coefficients of a 3rd order polynomial fit based on fishtest data
      // for two parameters needed to transform eval to the argument of a
      // logistic function.
-     double as[] = {-8.24404295, 64.23892342, -95.73056462, 153.86478679};
+     double as[] = {-3.68389304,  30.07065921, -60.52878723, 149.53378557};
-     double bs[] = {-3.37154371, 28.44489198, -56.67657741,  72.05858751};
+     double bs[] = {-2.0181857,   15.85685038, -29.83452023,  47.59078827};
      double a = (((as[0] * m + as[1]) * m + as[2]) * m) + as[3];
      double b = (((bs[0] * m + bs[1]) * m + bs[2]) * m) + bs[3];
 
      // Transform eval to centipawns with limited range
-     double x = std::clamp(double(100 * v) / PawnValueEg, -1000.0, 1000.0);
+     double x = std::clamp(double(100 * v) / PawnValueEg, -2000.0, 2000.0);
 
      // Return win rate in per mille (rounded to nearest)
      return int(0.5 + 1000 / (1 + std::exp((a - x) / b)));
@@ -275,7 +277,15 @@ void UCI::loop(int argc, char* argv[]) {
       else if (token == "d")        sync_cout << pos << sync_endl;
       else if (token == "eval")     trace_eval(pos);
       else if (token == "compiler") sync_cout << compiler_info() << sync_endl;
-      else
+      else if (token == "export_net")
+      {
+          std::optional<std::string> filename;
+          std::string f;
+          if (is >> skipws >> f)
+              filename = f;
+          Eval::NNUE::save_eval(filename);
+      }
+      else if (!token.empty() && token[0] != '#')
           sync_cout << "Unknown command: " << cmd << sync_endl;
 
   } while (token != "quit" && argc == 1); // Command line args are one-shot
@@ -369,3 +379,5 @@ Move UCI::to_move(const Position& pos, string& str) {
 
   return MOVE_NONE;
 }
+
+} // namespace Stockfish

src/uci.h

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -24,6 +24,8 @@
 
 #include "types.h"
 
+namespace Stockfish {
+
 class Position;
 
 namespace UCI {
@@ -78,4 +80,6 @@ Move to_move(const Position& pos, std::string& str);
 
 extern UCI::OptionsMap Options;
 
+} // namespace Stockfish
+
 #endif // #ifndef UCI_H_INCLUDED

src/ucioption.cpp

@@ -1,6 +1,6 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
-  Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
+  Copyright (C) 2004-2022 The Stockfish developers (see AUTHORS file)
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -31,6 +31,8 @@
 
 using std::string;
 
+namespace Stockfish {
+
 UCI::OptionsMap Options; // Global object
 
 namespace UCI {
@@ -59,8 +61,6 @@ void init(OptionsMap& o) {
   constexpr int MaxHashMB = Is64Bit ? 33554432 : 2048;
 
   o["Debug Log File"]        << Option("", on_logger);
-  o["Contempt"]              << Option(24, -100, 100);
-  o["Analysis Contempt"]     << Option("Both var Off var White var Black var Both", "Both");
   o["Threads"]               << Option(1, 1, 512, on_threads);
   o["Hash"]                  << Option(16, 1, MaxHashMB, on_hash_size);
   o["Clear Hash"]            << Option(on_clear_hash);
@@ -164,7 +164,7 @@ Option& Option::operator=(const string& v) {
 
   assert(!type.empty());
 
-  if (   (type != "button" && v.empty())
+  if (   (type != "button" && type != "string" && v.empty())
       || (type == "check" && v != "true" && v != "false")
       || (type == "spin" && (stof(v) < min || stof(v) > max)))
       return *this;
@@ -190,3 +190,5 @@ Option& Option::operator=(const string& v) {
 }
 
 } // namespace UCI
+
+} // namespace Stockfish

tests/instrumented.sh

@@ -13,7 +13,7 @@ case $1 in
   --valgrind)
     echo "valgrind testing started"
     prefix=''
-    exeprefix='valgrind --error-exitcode=42'
+    exeprefix='valgrind --error-exitcode=42 --errors-for-leak-kinds=all --leak-check=full'
     postfix='1>/dev/null'
     threads="1"
   ;;
@@ -39,16 +39,16 @@ case $1 in
     threads="2"
 
 cat << EOF > tsan.supp
-race:TTEntry::move
+race:Stockfish::TTEntry::move
-race:TTEntry::depth
+race:Stockfish::TTEntry::depth
-race:TTEntry::bound
+race:Stockfish::TTEntry::bound
-race:TTEntry::save
+race:Stockfish::TTEntry::save
-race:TTEntry::value
+race:Stockfish::TTEntry::value
-race:TTEntry::eval
+race:Stockfish::TTEntry::eval
-race:TTEntry::is_pv
+race:Stockfish::TTEntry::is_pv
 
-race:TranspositionTable::probe
+race:Stockfish::TranspositionTable::probe
-race:TranspositionTable::hashfull
+race:Stockfish::TranspositionTable::hashfull
 
 EOF
 
@@ -98,7 +98,7 @@ cat << EOF > game.exp
  expect "bestmove"
 
  send "position fen 5rk1/1K4p1/8/8/3B4/8/8/8 b - - 0 1\n"
- send "go depth 20\n"
+ send "go depth 10\n"
  expect "bestmove"
 
  send "quit\n"

tests/reprosearch.sh

@@ -10,7 +10,7 @@ trap 'error ${LINENO}' ERR
 
 echo "reprosearch testing started"
 
-# repeat two short games, separated by ucinewgame. 
+# repeat two short games, separated by ucinewgame.
 # with go nodes $nodes they should result in exactly
 # the same node count for each iteration.
 cat << EOF > repeat.exp
@@ -43,7 +43,7 @@ cat << EOF > repeat.exp
  expect eof
 EOF
 
-# to increase the likelyhood of finding a non-reproducible case,
+# to increase the likelihood of finding a non-reproducible case,
 # the allowed number of nodes are varied systematically
 for i in `seq 1 20`
 do