X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.cpp;h=474e321c09fff8184330be1f27c79dae7c904d6f;hp=5dd0137da39d225d34b4a41bb48279851fa29644;hb=9c428afb6dd0dcba2aa4e2a367a6b35c6f335be0;hpb=9ae2b6923504064da184d08b888fffb328818543

diff --git a/src/bitboard.cpp b/src/bitboard.cpp
index 5dd0137d..474e321c 100644
--- a/src/bitboard.cpp
+++ b/src/bitboard.cpp
@@ -1,13 +1,14 @@
 /*
-  Glaurung, a UCI chess playing engine.
-  Copyright (C) 2004-2008 Tord Romstad
+  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+  Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
+  Copyright (C) 2008-2009 Marco Costalba
 
-  Glaurung is free software: you can redistribute it and/or modify
+  Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.
 
-  Glaurung is distributed in the hope that it will be useful,
+  Stockfish is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
@@ -21,70 +22,22 @@
 //// Includes
 ////
 
+#ifdef _MSC_VER
+    #include <intrin.h>
+    #ifdef _WIN64
+        #pragma intrinsic(_BitScanForward64)
+    #else
+        #pragma intrinsic(_BitScanForward)
+    #endif
+    #define USING_INTRINSICS
+#endif
+
 #include <iostream>
 
 #include "bitboard.h"
 #include "direction.h"
 
 
-////
-//// Constants and variables
-////
-
-const Bitboard SquaresByColorBB[2] = {BlackSquaresBB, WhiteSquaresBB};
-
-const Bitboard FileBB[8] = {
-  FileABB, FileBBB, FileCBB, FileDBB, FileEBB, FileFBB, FileGBB, FileHBB
-};
-
-const Bitboard NeighboringFilesBB[8] = {
-  FileBBB, FileABB|FileCBB, FileBBB|FileDBB, FileCBB|FileEBB,
-  FileDBB|FileFBB, FileEBB|FileGBB, FileFBB|FileHBB, FileGBB
-};
-
-const Bitboard ThisAndNeighboringFilesBB[8] = {
-  FileABB|FileBBB, FileABB|FileBBB|FileCBB,
-  FileBBB|FileCBB|FileDBB, FileCBB|FileDBB|FileEBB,
-  FileDBB|FileEBB|FileFBB, FileEBB|FileFBB|FileGBB,
-  FileFBB|FileGBB|FileHBB, FileGBB|FileHBB
-};
-
-const Bitboard RankBB[8] = {
-  Rank1BB, Rank2BB, Rank3BB, Rank4BB, Rank5BB, Rank6BB, Rank7BB, Rank8BB
-};
-
-const Bitboard RelativeRankBB[2][8] = {
-  {
-    Rank1BB, Rank2BB, Rank3BB, Rank4BB, Rank5BB, Rank6BB, Rank7BB, Rank8BB
-  },
-  {
-    Rank8BB, Rank7BB, Rank6BB, Rank5BB, Rank4BB, Rank3BB, Rank2BB, Rank1BB
-  }
-};
-
-const Bitboard InFrontBB[2][8] = {
-  {
-    Rank2BB | Rank3BB | Rank4BB | Rank5BB | Rank6BB | Rank7BB | Rank8BB,
-    Rank3BB | Rank4BB | Rank5BB | Rank6BB | Rank7BB | Rank8BB,
-    Rank4BB | Rank5BB | Rank6BB | Rank7BB | Rank8BB,
-    Rank5BB | Rank6BB | Rank7BB | Rank8BB,
-    Rank6BB | Rank7BB | Rank8BB,
-    Rank7BB | Rank8BB,
-    Rank8BB,
-    EmptyBoardBB
-  },
-  {
-    EmptyBoardBB,
-    Rank1BB,
-    Rank2BB | Rank1BB,
-    Rank3BB | Rank2BB | Rank1BB,
-    Rank4BB | Rank3BB | Rank2BB | Rank1BB,
-    Rank5BB | Rank4BB | Rank3BB | Rank2BB | Rank1BB,
-    Rank6BB | Rank5BB | Rank4BB | Rank3BB | Rank2BB | Rank1BB,
-    Rank7BB | Rank6BB | Rank5BB | Rank4BB | Rank3BB | Rank2BB | Rank1BB
-  }
-};
-
 #if defined(USE_COMPACT_ROOK_ATTACKS)
 
 Bitboard RankAttacks[8][64], FileAttacks[8][64];
@@ -239,8 +192,8 @@ Bitboard BMask[64];
 int BAttackIndex[64];
 Bitboard BAttacks[0x1480];
 
-Bitboard SetMaskBB[64];
-Bitboard ClearMaskBB[64];
+Bitboard SetMaskBB[65];
+Bitboard ClearMaskBB[65];
 
 Bitboard StepAttackBB[16][64];
 Bitboard RayBB[64][8];
@@ -259,6 +212,7 @@ Bitboard QueenPseudoAttacks[64];
 ////
 
 namespace {
+
   void init_masks();
   void init_ray_bitboards();
   void init_attacks();
@@ -274,7 +228,7 @@ namespace {
 #if defined(USE_COMPACT_ROOK_ATTACKS)
   void init_file_and_rank_attacks();
 #endif
-};
+}
 
 
 ////
@@ -341,19 +295,36 @@ Square first_1(Bitboard b) {
 
 #if defined(USE_32BIT_ATTACKS)
 
+// Use type-punning
+union b_union {
+
+    Bitboard b;
+    struct {
+        uint32_t l;
+        uint32_t h;
+    } dw;
+};
+
+// WARNING: Needs -fno-strict-aliasing compiler option
 Square pop_1st_bit(Bitboard *bb) {
 
-  uint32_t  t = uint32_t(*bb);
-  uint32_t* p = t ? (uint32_t*)bb : (uint32_t*)bb + 1; // Little endian only?
-  uint32_t  b = t ? t : *p;
+  b_union u;
+  uint32_t b;
 
-  *p = b & (b -1);
+  u.b = *bb;
 
-  if (t)
-     b ^= (b - 1);
+  if (u.dw.l)
+  {
+      b = u.dw.l;
+      *((uint32_t*)bb) = b & (b - 1);
+      b ^= (b - 1);
+  }
   else
-     b = ~(b ^ (b - 1));
-
+  {
+      b = u.dw.h;
+      *((uint32_t*)bb+1) = b & (b - 1); // Little endian only?
+      b = ~(b ^ (b - 1));
+  }
   return Square(BitTable[(b * 0x783a9b23) >> 26]);
 }
 
@@ -405,6 +376,8 @@ namespace {
   // be necessary to touch any of them.
 
   void init_masks() {
+    SetMaskBB[SQ_NONE] = 0ULL;
+    ClearMaskBB[SQ_NONE] = ~SetMaskBB[SQ_NONE];
     for(Square s = SQ_A1; s <= SQ_H8; s++) {
       SetMaskBB[s] = (1ULL << s);
       ClearMaskBB[s] = ~SetMaskBB[s];
@@ -420,7 +393,7 @@ namespace {
 
   void init_ray_bitboards() {
     int d[8] = {1, -1, 16, -16, 17, -17, 15, -15};
-    for(int i = 0; i < 128; i = i + 9 & ~8) {
+    for(int i = 0; i < 128; i = (i + 9) & ~8) {
       for(int j = 0; j < 8; j++) {
         RayBB[(i&7)|((i>>4)<<3)][j] = EmptyBoardBB;
         for(int k = i + d[j]; (k & 0x88) == 0; k += d[j])
@@ -506,8 +479,15 @@ namespace {
     for(i = 0; i < 64; i++) {
       attackIndex[i] = index;
       mask[i] = sliding_attacks(i, 0ULL, 4, deltas, 1, 6, 1, 6);
+
+#if defined(USE_32BIT_ATTACKS)
+      j = (1 << (32 - shift[i]));
+#else
       j = (1 << (64 - shift[i]));
+#endif
+
       for(k = 0; k < j; k++) {
+
 #if defined(USE_32BIT_ATTACKS)
         b = index_to_bitboard(k, mask[i]);
         attacks[index +