X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fbitboard.cpp;h=fd3db6715b6e15278a5c8d382d37798132adc37b;hp=7687cbb4441cb5cf66c40277c39a5532be4f8178;hb=1ff5ce8863cb71f42dc0f707dd566e566c658eb5;hpb=091aff044516fcd8700a8a194f9e9ffaabed8bb4

diff --git a/src/bitboard.cpp b/src/bitboard.cpp
index 7687cbb4..fd3db671 100644
--- a/src/bitboard.cpp
+++ b/src/bitboard.cpp
@@ -19,11 +19,10 @@
 
 #include <algorithm>
 #include <cstring>
-#include <iostream>
+#include <sstream>
 
 #include "bitboard.h"
 #include "bitcount.h"
-#include "misc.h"
 #include "rkiss.h"
 
 CACHE_LINE_ALIGNMENT
@@ -81,8 +80,8 @@ namespace {
   }
 }
 
-/// lsb()/msb() finds the least/most significant bit in a nonzero bitboard.
-/// pop_lsb() finds and clears the least significant bit in a nonzero bitboard.
+/// lsb()/msb() finds the least/most significant bit in a non-zero bitboard.
+/// pop_lsb() finds and clears the least significant bit in a non-zero bitboard.
 
 #ifndef USE_BSFQ
 
@@ -126,23 +125,24 @@ Square msb(Bitboard b) {
 #endif // ifndef USE_BSFQ
 
 
-/// Bitboards::print() prints a bitboard in an easily readable format to the
-/// standard output. This is sometimes useful for debugging.
+/// Bitboards::pretty() returns an ASCII representation of a bitboard to be
+/// printed to standard output. This is sometimes useful for debugging.
 
-void Bitboards::print(Bitboard b) {
+const std::string Bitboards::pretty(Bitboard b) {
 
-  sync_cout;
+  std::ostringstream ss;
 
   for (Rank rank = RANK_8; rank >= RANK_1; --rank)
   {
-      std::cout << "+---+---+---+---+---+---+---+---+" << '\n';
+      ss << "+---+---+---+---+---+---+---+---+" << '\n';
 
       for (File file = FILE_A; file <= FILE_H; ++file)
-          std::cout << "| " << (b & (file | rank) ? "X " : "  ");
+          ss << "| " << (b & (file | rank) ? "X " : "  ");
 
-      std::cout << "|\n";
+      ss << "|\n";
   }
-  std::cout << "+---+---+---+---+---+---+---+---+" << sync_endl;
+  ss << "+---+---+---+---+---+---+---+---+";
+  return ss.str();
 }
 
 
@@ -151,15 +151,11 @@ void Bitboards::print(Bitboard b) {
 
 void Bitboards::init() {
 
-  for (int k = 0, i = 0; i < 8; ++i)
-      while (k < (2 << i))
-          MS1BTable[k++] = i;
-
-  for (int i = 0; i < 64; ++i)
-      BSFTable[bsf_index(1ULL << i)] = Square(i);
-
   for (Square s = SQ_A1; s <= SQ_H8; ++s)
-      SquareBB[s] = 1ULL << s;
+      BSFTable[bsf_index(SquareBB[s] = 1ULL << s)] = s;
+
+  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;
@@ -198,9 +194,9 @@ void Bitboards::init() {
   for (Color c = WHITE; c <= BLACK; ++c)
       for (PieceType pt = PAWN; pt <= KING; ++pt)
           for (Square s = SQ_A1; s <= SQ_H8; ++s)
-              for (int k = 0; steps[pt][k]; ++k)
+              for (int i = 0; steps[pt][i]; ++i)
               {
-                  Square to = s + Square(c == WHITE ? steps[pt][k] : -steps[pt][k]);
+                  Square to = s + Square(c == WHITE ? steps[pt][i] : -steps[pt][i]);
 
                   if (is_ok(to) && square_distance(s, to) < 3)
                       StepAttacksBB[make_piece(c, pt)][s] |= to;
@@ -212,24 +208,23 @@ void Bitboards::init() {
   init_magics(RTable, RAttacks, RMagics, RMasks, RShifts, RDeltas, magic_index<ROOK>);
   init_magics(BTable, BAttacks, BMagics, BMasks, BShifts, BDeltas, magic_index<BISHOP>);
 
-  for (Square s = SQ_A1; s <= SQ_H8; ++s)
+  for (Square s1 = SQ_A1; s1 <= SQ_H8; ++s1)
   {
-      PseudoAttacks[QUEEN][s]  = PseudoAttacks[BISHOP][s] = attacks_bb<BISHOP>(s, 0);
-      PseudoAttacks[QUEEN][s] |= PseudoAttacks[  ROOK][s] = attacks_bb<  ROOK>(s, 0);
-  }
+      PseudoAttacks[QUEEN][s1]  = PseudoAttacks[BISHOP][s1] = attacks_bb<BISHOP>(s1, 0);
+      PseudoAttacks[QUEEN][s1] |= PseudoAttacks[  ROOK][s1] = attacks_bb<  ROOK>(s1, 0);
 
-  for (Square s1 = SQ_A1; s1 <= SQ_H8; ++s1)
       for (Square s2 = SQ_A1; s2 <= SQ_H8; ++s2)
-          if (PseudoAttacks[QUEEN][s1] & s2)
-          {
-              Square delta = (s2 - s1) / square_distance(s1, s2);
+      {
+          Piece pc = (PseudoAttacks[BISHOP][s1] & s2) ? W_BISHOP :
+                     (PseudoAttacks[ROOK][s1]   & s2) ? W_ROOK   : NO_PIECE;
 
-              for (Square s = s1 + delta; s != s2; s += delta)
-                  BetweenBB[s1][s2] |= s;
+          if (pc == NO_PIECE)
+              continue;
 
-              PieceType pc = (PseudoAttacks[BISHOP][s1] & s2) ? BISHOP : ROOK;
-              LineBB[s1][s2] = (PseudoAttacks[pc][s1] & PseudoAttacks[pc][s2]) | s1 | s2;
-          }
+          LineBB[s1][s2] = (attacks_bb(pc, s1, 0) & attacks_bb(pc, s2, 0)) | s1 | s2;
+          BetweenBB[s1][s2] = attacks_bb(pc, s1, SquareBB[s2]) & attacks_bb(pc, s2, SquareBB[s1]);
+      }
+  }
 }
 
 
@@ -257,7 +252,7 @@ namespace {
   Bitboard pick_random(RKISS& rk, int booster) {
 
     // Values s1 and s2 are used to rotate the candidate magic of a
-    // quantity known to be the optimal to quickly find the magics.
+    // quantity known to be optimal to quickly find the magics.
     int s1 = booster & 63, s2 = (booster >> 6) & 63;
 
     Bitboard m = rk.rand<Bitboard>();