kate/BadFish
1
0
Fork 0
mirror of https://github.com/sockspls/badfish synced 2025-04-30 08:43:09 +00:00
Code Issues Releases Wiki Activity

Introduce movecount pruning for qsearch()

Browse source 
If in quiescence search, we assume that me can prune late moves when:

a) the move ordering count of the move is : moveCount > abs(depth) + 2
b) we are not in check
c) the late move does not give check
d) the late move is not an advanced pawn push

Modification of an original idea by @VoyagerOne.

STC
https://tests.stockfishchess.org/tests/view/5f40581787a5c3c63d8f535f
LLR: 2.96 (-2.94,2.94) {-0.25,1.25}
Total: 132848 W: 14999 L: 14661 D: 103188
Ptnml(0-2): 684, 11242, 42309, 11430, 759

LTC
https://tests.stockfishchess.org/tests/view/5f4226da87a5c3c63d8f5412
LLR: 2.98 (-2.94,2.94) {0.25,1.25}
Total: 12008 W: 678 L: 551 D: 10779
Ptnml(0-2): 8, 485, 4899, 596, 16

closes https://github.com/official-stockfish/Stockfish/pull/3053

Bench: 3749974
This commit is contained in:
Vizvezdenec 2020-08-23 14:22:32 +03:00 • committed by Stéphane Nicolet
parent cc9d503dde
commit d5f86b6359
2 changed files with 6 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
src/search.cpp
View file

@ -1531,6 +1531,10 @@ moves_loop: // When in check, search starts from here
{ {
assert(type_of(move) != ENPASSANT); // Due to !pos.advanced_pawn_push assert(type_of(move) != ENPASSANT); // Due to !pos.advanced_pawn_push
// moveCount pruning
if (moveCount > abs(depth) + 2)
continue;
futilityValue = futilityBase + PieceValue[EG][pos.piece_on(to_sq(move))]; futilityValue = futilityBase + PieceValue[EG][pos.piece_on(to_sq(move))];
if (futilityValue <= alpha) if (futilityValue <= alpha)
@ -1547,7 +1551,7 @@ moves_loop: // When in check, search starts from here
} }
// Do not search moves with negative SEE values // Do not search moves with negative SEE values
if ( !ss->inCheck && !pos.see_ge(move)) if (!ss->inCheck && !pos.see_ge(move))
continue; continue;
// Speculative prefetch as early as possible // Speculative prefetch as early as possible