kate/BadFish
1
0
Fork 0
mirror of https://github.com/sockspls/badfish synced 2025-06-28 00:19:50 +00:00
Code Issues Releases Wiki Activity

Use NNUE in low piece endgames close to the root.

Browse source 
This patch enforces that NNUE evaluation is used for endgame positions at shallow depth (depth <= 9).
Classic evaluation will still be used for high imbalance positions when the depth is high or there are many pieces.

Passed STC:
https://tests.stockfishchess.org/tests/view/624c193b3a8a6ac93892dc27
LLR: 2.94 (-2.94,2.94) <0.00,2.50>
Total: 255840 W: 68024 L: 67362 D: 120454
Ptnml(0-2): 1074, 27089, 70926, 27763, 1068

Passed LTC:
https://tests.stockfishchess.org/tests/view/624e8675e9e7821808467f77
LLR: 2.94 (-2.94,2.94) <0.50,3.00>
Total: 67088 W: 17784 L: 17454 D: 31850
Ptnml(0-2): 45, 6209, 20715, 6521, 54

closes https://github.com/official-stockfish/Stockfish/pull/3978

bench: 6602222
This commit is contained in:
Topologist 2022-04-09 08:55:40 +02:00 • committed by Joost VandeVondele
parent 9f6bcb38c0
commit 19a90b45bc
3 changed files with 5 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
src/evaluate.cpp
View file

@ -1088,7 +1088,8 @@ Value Eval::evaluate(const Position& pos) {
// Deciding between classical and NNUE eval (~10 Elo): for high PSQ imbalance we use classical,
// but we switch to NNUE during long shuffling or with high material on the board.
if ( !useNNUE
|| abs(eg_value(pos.psq_score())) * 5 > (856 + pos.non_pawn_material() / 64) * (5 + pos.rule50_count()))
|| ((pos.this_thread()->depth > 9 || pos.count<ALL_PIECES>() > 7) &&
abs(eg_value(pos.psq_score())) * 5 > (856 + pos.non_pawn_material() / 64) * (5 + pos.rule50_count())))
{
v = Evaluation<NO_TRACE>(pos).value(); // classical
useClassical = abs(v) >= 297;
@ -1138,6 +1139,7 @@ std::string Eval::trace(Position& pos) {
std::memset(scores, 0, sizeof(scores));
// Reset any global variable used in eval
pos.this_thread()->depth = 0;
pos.this_thread()->trend = SCORE_ZERO;
pos.this_thread()->bestValue = VALUE_ZERO;
pos.this_thread()->optimism[WHITE] = VALUE_ZERO;

1
src/search.cpp
View file

@ -560,6 +560,7 @@ namespace {
// Step 1. Initialize node
Thread* thisThread = pos.this_thread();
thisThread->depth = depth;
ss->inCheck = pos.checkers();
priorCapture = pos.captured_piece();
Color us = pos.side_to_move();

2
src/thread.h
View file

@ -69,7 +69,7 @@ public:
Position rootPos;
StateInfo rootState;
Search::RootMoves rootMoves;
Depth rootDepth, completedDepth;
Depth rootDepth, completedDepth, depth;
Value rootDelta;
CounterMoveHistory counterMoves;
ButterflyHistory mainHistory;