Lookup square distance instead of calculate on the fly

[stockfish] / src / pawns.cpp

diff --git a/src/pawns.cpp b/src/pawns.cpp
index 3ad88fb206aa011ece4fb6dca4c75acf17edb758..b3c65a0f166268200fb918d4a751f2563f7de378 100644 (file)
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -79,8 +79,6 @@ namespace {
 
 PawnInfo* PawnInfoTable::get_pawn_info(const Position& pos) const {
 
-  assert(pos.is_ok());
-
   Key key = pos.get_pawn_key();
   PawnInfo* pi = probe(key);
 
@@ -127,10 +125,10 @@ Score PawnInfoTable::evaluate_pawns(const Position& pos, Bitboard ourPawns,
   Rank r;
   bool passed, isolated, doubled, opposed, chain, backward, candidate;
   Score value = SCORE_ZERO;
-  const Square* ptr = pos.piece_list_begin(Us, PAWN);
+  const Square* pl = pos.piece_list(Us, PAWN);
 
   // Loop through all pawns of the current color and score each pawn
-  while ((s = *ptr++) != SQ_NONE)
+  while ((s = *pl++) != SQ_NONE)
   {
       assert(pos.piece_on(s) == make_piece(Us, PAWN));
 
@@ -230,7 +228,7 @@ Score PawnInfo::updateShelter(const Position& pos, Square ksq) {
       for (int i = 0; i < 3; i++)
       {
           r += Shift;
-          shelter += BitCount8Bit[(pawns >> r) & 0xFF] * (64 >> i);
+          shelter += BitCount8Bit[(pawns >> r) & 0xFF] << (6 - i);
       }
   }
   kingSquares[Us] = ksq;