X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitbase.cpp;h=9301dcfad13ea51797b10d44e3011c9b7fa36f90;hp=1a6e807603a88a6143f403c8314215a0fd4ad527;hb=9f312c80d918c6f669dcf83df3d4332e02bfa1d9;hpb=d8f683760c9eb6d2c4714ec83e717dd2143de55c diff --git a/src/bitbase.cpp b/src/bitbase.cpp index 1a6e8076..9301dcfa 100644 --- a/src/bitbase.cpp +++ b/src/bitbase.cpp @@ -2,7 +2,7 @@ Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad - Copyright (C) 2015-2017 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad + Copyright (C) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -18,7 +18,6 @@ along with this program. If not, see . */ -#include #include #include #include @@ -28,8 +27,9 @@ namespace { - // There are 24 possible pawn squares: the first 4 files and ranks from 2 to 7 - const unsigned MAX_INDEX = 2*24*64*64; // stm * psq * wksq * bksq = 196608 + // There are 24 possible pawn squares: files A to D and ranks from 2 to 7. + // Positions with the pawn on files E to H will be mirrored before probing. + constexpr unsigned MAX_INDEX = 2*24*64*64; // stm * psq * wksq * bksq = 196608 // Each uint32_t stores results of 32 positions, one per bit uint32_t KPKBitbase[MAX_INDEX / 32]; @@ -44,7 +44,7 @@ namespace { // bit 13-14: white pawn file (from FILE_A to FILE_D) // bit 15-17: white pawn RANK_7 - rank (from RANK_7 - RANK_7 to RANK_7 - RANK_2) unsigned index(Color us, Square bksq, Square wksq, Square psq) { - return wksq | (bksq << 6) | (us << 12) | (file_of(psq) << 13) | ((RANK_7 - rank_of(psq)) << 15); + return int(wksq) | (bksq << 6) | (us << 12) | (file_of(psq) << 13) | ((RANK_7 - rank_of(psq)) << 15); } enum Result { @@ -111,13 +111,13 @@ namespace { ksq[WHITE] = Square((idx >> 0) & 0x3F); ksq[BLACK] = Square((idx >> 6) & 0x3F); us = Color ((idx >> 12) & 0x01); - psq = make_square(File((idx >> 13) & 0x3), RANK_7 - Rank((idx >> 15) & 0x7)); + psq = make_square(File((idx >> 13) & 0x3), Rank(RANK_7 - ((idx >> 15) & 0x7))); // Check if two pieces are on the same square or if a king can be captured if ( distance(ksq[WHITE], ksq[BLACK]) <= 1 || ksq[WHITE] == psq || ksq[BLACK] == psq - || (us == WHITE && (StepAttacksBB[PAWN][psq] & ksq[BLACK]))) + || (us == WHITE && (PawnAttacks[WHITE][psq] & ksq[BLACK]))) result = INVALID; // Immediate win if a pawn can be promoted without getting captured @@ -125,13 +125,13 @@ namespace { && rank_of(psq) == RANK_7 && ksq[us] != psq + NORTH && ( distance(ksq[~us], psq + NORTH) > 1 - || (StepAttacksBB[KING][ksq[us]] & (psq + NORTH)))) + || (PseudoAttacks[KING][ksq[us]] & (psq + NORTH)))) result = WIN; // Immediate draw if it is a stalemate or a king captures undefended pawn else if ( us == BLACK - && ( !(StepAttacksBB[KING][ksq[us]] & ~(StepAttacksBB[KING][ksq[~us]] | StepAttacksBB[PAWN][psq])) - || (StepAttacksBB[KING][ksq[us]] & psq & ~StepAttacksBB[KING][ksq[~us]]))) + && ( !(PseudoAttacks[KING][ksq[us]] & ~(PseudoAttacks[KING][ksq[~us]] | PawnAttacks[~us][psq])) + || (PseudoAttacks[KING][ksq[us]] & psq & ~PseudoAttacks[KING][ksq[~us]]))) result = DRAW; // Position will be classified later @@ -152,12 +152,12 @@ namespace { // as WIN, the position is classified as WIN, otherwise the current position is // classified as UNKNOWN. - const Color Them = (Us == WHITE ? BLACK : WHITE); - const Result Good = (Us == WHITE ? WIN : DRAW); - const Result Bad = (Us == WHITE ? DRAW : WIN); + constexpr Color Them = (Us == WHITE ? BLACK : WHITE); + constexpr Result Good = (Us == WHITE ? WIN : DRAW); + constexpr Result Bad = (Us == WHITE ? DRAW : WIN); Result r = INVALID; - Bitboard b = StepAttacksBB[KING][ksq[Us]]; + Bitboard b = PseudoAttacks[KING][ksq[Us]]; while (b) r |= Us == WHITE ? db[index(Them, ksq[Them] , pop_lsb(&b), psq)]