Avoid 'double assigments' tricks

[stockfish] / src / bitboard.cpp

diff --git a/src/bitboard.cpp b/src/bitboard.cpp
index 27ba65747d6faf05cf4cdb3e2442aa0f0b7cdbe6..ff10b4ff7026524955953dc0d76806b3e32b2d3f 100644 (file)
--- a/src/bitboard.cpp
+++ b/src/bitboard.cpp
@@ -79,23 +79,6 @@ namespace {
   }
 }
 
-
-/// Intel PEXT (parallel extraction) software implementation
-Bitboard pext(Bitboard b, Bitboard mask) {
-
-  Bitboard res = 0;
-
-  for (Bitboard bb = 1; mask; bb += bb)
-  {
-      if (b & mask & -mask)
-          res |= bb;
-
-      mask &= mask - 1;
-  }
-  return res;
-}
-
-
 /// 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.
 
@@ -166,7 +149,10 @@ const std::string Bitboards::pretty(Bitboard b) {
 void Bitboards::init() {
 
   for (Square s = SQ_A1; s <= SQ_H8; ++s)
-      BSFTable[bsf_index(SquareBB[s] = 1ULL << s)] = s;
+  {
+      SquareBB[s] = 1ULL << s;
+      BSFTable[bsf_index(SquareBB[s])] = s;
+  }
 
   for (Bitboard b = 1; b < 256; ++b)
       MS1BTable[b] = more_than_one(b) ? MS1BTable[b - 1] : lsb(b);
@@ -296,7 +282,12 @@ namespace {
         b = size = 0;
         do {
             occupancy[size] = b;
-            reference[size++] = sliding_attack(deltas, s, b);
+            reference[size] = sliding_attack(deltas, s, b);
+
+            if (HasPext)
+                attacks[s][_pext_u64(b, masks[s])] = reference[size];
+
+            size++;
             b = (b - masks[s]) & masks[s];
         } while (b);
 
@@ -305,12 +296,16 @@ namespace {
         if (s < SQ_H8)
             attacks[s + 1] = attacks[s] + size;
 
+        if (HasPext)
+            continue;
+
         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.
         do {
-            do magics[s] = rk.magic_rand<Bitboard>(booster);
+            do
+                magics[s] = rk.magic_rand<Bitboard>(booster);
             while (popcount<Max15>((magics[s] * masks[s]) >> 56) < 6);
 
             std::memset(attacks[s], 0, size * sizeof(Bitboard));