This simplification allows the almostUnwinnable flag to match endgames where the pawns are all on the same flank but are not symmetrical.
STC:
LLR: 2.94 (-2.94,2.94) {-1.50,0.50}
Total: 23356 W: 4543 L: 4395 D: 14418
Ptnml(0-2): 346, 2651, 5582, 2707, 392
https://tests.stockfishchess.org/tests/view/
5e7b8f57e42a5c3b3ca2eb09
LTC:
LLR: 2.96 (-2.94,2.94) {-1.50,0.50}
Total: 31778 W: 4097 L: 4023 D: 23658
Ptnml(0-2): 199, 2853, 9729, 2891, 217
https://tests.stockfishchess.org/tests/view/
5e7ba5ade42a5c3b3ca2eb16
closes https://github.com/official-stockfish/Stockfish/pull/2596
Bench
4777139
bool pawnsOnBothFlanks = (pos.pieces(PAWN) & QueenSide)
&& (pos.pieces(PAWN) & KingSide);
- bool almostUnwinnable = !pe->passed_count()
- && outflanking < 0
+ bool almostUnwinnable = outflanking < 0
&& !pawnsOnBothFlanks;
bool infiltration = rank_of(pos.square<KING>(WHITE)) > RANK_4