X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.cpp;h=138d8c72b0c51dbe324397c98c1a13d65b5736f1;hp=b36f8a291d77647b5af8d1888bc83efabf0542d3;hb=3ec94abcdb5f4ad81cc8829aece2d7fa64bb21db;hpb=22b9307aba0f78aa92abcf85e807af8b64011c7a
diff --git a/src/bitboard.cpp b/src/bitboard.cpp
index b36f8a29..138d8c72 100644
--- a/src/bitboard.cpp
+++ b/src/bitboard.cpp
@@ -1,7 +1,7 @@
/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, 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
@@ -17,16 +17,14 @@
along with this program. If not, see .
*/
+#include
#include
#include
-#include
#include "bitboard.h"
#include "bitcount.h"
#include "rkiss.h"
-// Global bitboards definitions with static storage duration are
-// automatically set to zero before enter main().
Bitboard RMasks[64];
Bitboard RMagics[64];
Bitboard* RAttacks[64];
@@ -40,11 +38,10 @@ int BShifts[64];
Bitboard SetMaskBB[65];
Bitboard ClearMaskBB[65];
-Bitboard SquaresByColorBB[2];
Bitboard FileBB[8];
Bitboard RankBB[8];
-Bitboard NeighboringFilesBB[8];
-Bitboard ThisAndNeighboringFilesBB[8];
+Bitboard AdjacentFilesBB[8];
+Bitboard ThisAndAdjacentFilesBB[8];
Bitboard InFrontBB[2][8];
Bitboard StepAttacksBB[16][64];
Bitboard BetweenBB[64][64];
@@ -52,9 +49,7 @@ Bitboard SquaresInFrontMask[2][64];
Bitboard PassedPawnMask[2][64];
Bitboard AttackSpanMask[2][64];
-Bitboard BishopPseudoAttacks[64];
-Bitboard RookPseudoAttacks[64];
-Bitboard QueenPseudoAttacks[64];
+Bitboard PseudoAttacks[6][64];
uint8_t BitCount8Bit[256];
int SquareDistance[64][64];
@@ -151,20 +146,13 @@ Square pop_1st_bit(Bitboard* bb) {
#endif // !defined(USE_BSFQ)
-/// init_bitboards() initializes various bitboard arrays. It is called during
+/// bitboards_init() initializes various bitboard arrays. It is called during
/// program initialization.
-void init_bitboards() {
+void bitboards_init() {
for (Bitboard b = 0; b < 256; b++)
- BitCount8Bit[b] = (uint8_t)count_1s(b);
-
- 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));
-
- SquaresByColorBB[DARK] = 0xAA55AA55AA55AA55ULL;
- SquaresByColorBB[LIGHT] = ~SquaresByColorBB[DARK];
+ BitCount8Bit[b] = (uint8_t)popcount(b);
for (Square s = SQ_A1; s <= SQ_H8; s++)
{
@@ -172,7 +160,7 @@ void init_bitboards() {
ClearMaskBB[s] = ~SetMaskBB[s];
}
- ClearMaskBB[SQ_NONE] = ~EmptyBoardBB;
+ ClearMaskBB[SQ_NONE] = ~0ULL;
FileBB[FILE_A] = FileABB;
RankBB[RANK_1] = Rank1BB;
@@ -185,8 +173,8 @@ void init_bitboards() {
for (int f = FILE_A; f <= FILE_H; f++)
{
- NeighboringFilesBB[f] = (f > FILE_A ? FileBB[f - 1] : 0) | (f < FILE_H ? FileBB[f + 1] : 0);
- ThisAndNeighboringFilesBB[f] = FileBB[f] | NeighboringFilesBB[f];
+ AdjacentFilesBB[f] = (f > FILE_A ? FileBB[f - 1] : 0) | (f < FILE_H ? FileBB[f + 1] : 0);
+ ThisAndAdjacentFilesBB[f] = FileBB[f] | AdjacentFilesBB[f];
}
for (int rw = RANK_7, rb = RANK_2; rw >= RANK_1; rw--, rb++)
@@ -199,17 +187,21 @@ void init_bitboards() {
for (Square s = SQ_A1; s <= SQ_H8; s++)
{
SquaresInFrontMask[c][s] = in_front_bb(c, s) & file_bb(s);
- PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_neighboring_files_bb(s);
- AttackSpanMask[c][s] = in_front_bb(c, s) & neighboring_files_bb(s);
+ PassedPawnMask[c][s] = in_front_bb(c, s) & this_and_adjacent_files_bb(file_of(s));
+ AttackSpanMask[c][s] = in_front_bb(c, s) & adjacent_files_bb(file_of(s));
}
+ 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));
+
for (int i = 0; i < 64; i++)
- if (!CpuIs64Bit) // Matt Taylor's folding trick for 32 bit systems
+ if (!Is64Bit) // Matt Taylor's folding trick for 32 bit systems
{
Bitboard b = 1ULL << i;
b ^= b - 1;
b ^= b >> 32;
- BSFTable[uint32_t(b * 0x783A9B23) >> 26] = i;
+ BSFTable[(uint32_t)(b * 0x783A9B23) >> 26] = i;
}
else
BSFTable[((1ULL << i) * 0x218A392CD3D5DBFULL) >> 58] = i;
@@ -233,14 +225,14 @@ void init_bitboards() {
for (Square s = SQ_A1; s <= SQ_H8; s++)
{
- BishopPseudoAttacks[s] = bishop_attacks_bb(s, EmptyBoardBB);
- RookPseudoAttacks[s] = rook_attacks_bb(s, EmptyBoardBB);
- QueenPseudoAttacks[s] = queen_attacks_bb(s, EmptyBoardBB);
+ PseudoAttacks[BISHOP][s] = bishop_attacks_bb(s, 0);
+ PseudoAttacks[ROOK][s] = rook_attacks_bb(s, 0);
+ PseudoAttacks[QUEEN][s] = queen_attacks_bb(s, 0);
}
for (Square s1 = SQ_A1; s1 <= SQ_H8; s1++)
for (Square s2 = SQ_A1; s2 <= SQ_H8; s2++)
- if (bit_is_set(QueenPseudoAttacks[s1], s2))
+ if (bit_is_set(PseudoAttacks[QUEEN][s1], s2))
{
Square delta = (s2 - s1) / square_distance(s1, s2);
@@ -276,6 +268,7 @@ namespace {
return attacks;
}
+
Bitboard pick_random(Bitboard mask, RKISS& rk, int booster) {
Bitboard magic;
@@ -325,8 +318,8 @@ namespace {
// all the attacks for each possible subset of the mask and so is 2 power
// the number of 1s of the mask. Hence we deduce the size of the shift to
// apply to the 64 or 32 bits word to get the index.
- masks[s] = sliding_attacks(pt, s, EmptyBoardBB) & ~edges;
- shifts[s] = (CpuIs64Bit ? 64 : 32) - count_1s(masks[s]);
+ masks[s] = sliding_attacks(pt, s, 0) & ~edges;
+ shifts[s] = (Is64Bit ? 64 : 32) - popcount(masks[s]);
// Use Carry-Rippler trick to enumerate all subsets of masks[s] and
// store the corresponding sliding attacks bitboard in reference[].
@@ -342,7 +335,7 @@ namespace {
if (s < SQ_H8)
attacks[s + 1] = attacks[s] + size;
- booster = MagicBoosters[CpuIs64Bit][rank_of(s)];
+ booster = MagicBoosters[Is64Bit][rank_of(s)];
// Find a magic for square 's' picking up an (almost) random number
// until we find the one that passes the verification test.