From 4630ab574333be3cfabb6fcf3eca6d66ae961fe1 Mon Sep 17 00:00:00 2001 From: Marco Costalba Date: Sat, 7 Dec 2013 12:09:33 +0100 Subject: [PATCH] More work on Bitboards::init() No functional change. --- src/bitboard.cpp | 25 +++++++++++-------------- 1 file changed, 11 insertions(+), 14 deletions(-) diff --git a/src/bitboard.cpp b/src/bitboard.cpp index fd3db671..d0bd7e70 100644 --- a/src/bitboard.cpp +++ b/src/bitboard.cpp @@ -119,7 +119,7 @@ Square msb(Bitboard b) { result += 8; } - return (Square)(result + MS1BTable[b32]); + return Square(result + MS1BTable[b32]); } #endif // ifndef USE_BSFQ @@ -146,8 +146,8 @@ const std::string Bitboards::pretty(Bitboard b) { } -/// Bitboards::init() initializes various bitboard arrays. It is called during -/// program initialization. +/// Bitboards::init() initializes various bitboard tables. It is called at +/// startup and relies on global objects to be already zero-initialized. void Bitboards::init() { @@ -157,14 +157,11 @@ void Bitboards::init() { for (Bitboard b = 1; b < 256; ++b) MS1BTable[b] = more_than_one(b) ? MS1BTable[b - 1] : lsb(b); - FileBB[FILE_A] = FileABB; - RankBB[RANK_1] = Rank1BB; + for (File f = FILE_A; f <= FILE_H; ++f) + FileBB[f] = f > FILE_A ? FileBB[f - 1] << 1 : FileABB; - for (int i = 1; i < 8; ++i) - { - FileBB[i] = FileBB[i - 1] << 1; - RankBB[i] = RankBB[i - 1] << 8; - } + for (Rank r = RANK_1; r <= RANK_8; ++r) + RankBB[r] = r > RANK_1 ? RankBB[r - 1] << 8 : Rank1BB; for (File f = FILE_A; f <= FILE_H; ++f) AdjacentFilesBB[f] = (f > FILE_A ? FileBB[f - 1] : 0) | (f < FILE_H ? FileBB[f + 1] : 0); @@ -182,11 +179,11 @@ void Bitboards::init() { for (Square s1 = SQ_A1; s1 <= SQ_H8; ++s1) for (Square s2 = SQ_A1; s2 <= SQ_H8; ++s2) - { - SquareDistance[s1][s2] = std::max(file_distance(s1, s2), rank_distance(s1, s2)); if (s1 != s2) - DistanceRingsBB[s1][SquareDistance[s1][s2] - 1] |= s2; - } + { + SquareDistance[s1][s2] = std::max(file_distance(s1, s2), rank_distance(s1, s2)); + DistanceRingsBB[s1][SquareDistance[s1][s2] - 1] |= s2; + } int steps[][9] = { {}, { 7, 9 }, { 17, 15, 10, 6, -6, -10, -15, -17 }, {}, {}, {}, { 9, 7, -7, -9, 8, 1, -1, -8 } }; -- 2.39.2