Rename shift_bb() to shift()

[stockfish] / src / pawns.cpp

diff --git a/src/pawns.cpp b/src/pawns.cpp
index c5c42ff14a593bc08caf2d914c0cdda6846ce0b0..245ba0c6a90680403a785a5911f4885417f20704 100644 (file)
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -44,22 +44,22 @@ namespace {
   // Connected pawn bonus by opposed, phalanx, twice supported and rank
   Score Connected[2][2][2][RANK_NB];
 
-  // Doubled pawn penalty by file
-  const Score Doubled[FILE_NB] = {
-    S(11, 34), S(17, 38), S(19, 38), S(19, 38),
-    S(19, 38), S(19, 38), S(17, 38), S(11, 34) };
+  // Doubled pawn penalty
+  const Score Doubled = S(18,38);
 
   // Lever bonus by rank
   const Score Lever[RANK_NB] = {
     S( 0,  0), S( 0,  0), S(0, 0), S(0, 0),
-    S(17, 16), S(33, 32), S(0, 0), S(0, 0) };
+    S(17, 16), S(33, 32), S(0, 0), S(0, 0)
+  };
 
   // Weakness of our pawn shelter in front of the king by [distance from edge][rank]
   const Value ShelterWeakness[][RANK_NB] = {
     { V( 97), V(21), V(26), V(51), V(87), V( 89), V( 99) },
     { V(120), V( 0), V(28), V(76), V(88), V(103), V(104) },
     { V(101), V( 7), V(54), V(78), V(77), V( 92), V(101) },
-    { V( 80), V(11), V(44), V(68), V(87), V( 90), V(119) } };
+    { V( 80), V(11), V(44), V(68), V(87), V( 90), V(119) }
+  };
 
   // Danger of enemy pawns moving toward our king by [type][distance from edge][rank]
   const Value StormDanger[][4][RANK_NB] = {
@@ -78,7 +78,8 @@ namespace {
     { { V( 0),  V(-283), V(-281), V(57), V(31) },
       { V( 0),  V(  58), V( 141), V(39), V(18) },
       { V( 0),  V(  65), V( 142), V(48), V(32) },
-      { V( 0),  V(  60), V( 126), V(51), V(19) } } };
+      { V( 0),  V(  60), V( 126), V(51), V(19) } }
+  };
 
   // Max bonus for king safety. Corresponds to start position with all the pawns
   // in front of the king and no enemy pawn on the horizon.
@@ -90,10 +91,10 @@ namespace {
   template<Color Us>
   Score evaluate(const Position& pos, Pawns::Entry* e) {
 
-    const Color  Them  = (Us == WHITE ? BLACK    : WHITE);
-    const Square Up    = (Us == WHITE ? DELTA_N  : DELTA_S);
-    const Square Right = (Us == WHITE ? DELTA_NE : DELTA_SW);
-    const Square Left  = (Us == WHITE ? DELTA_NW : DELTA_SE);
+    const Color  Them  = (Us == WHITE ? BLACK      : WHITE);
+    const Square Up    = (Us == WHITE ? NORTH      : SOUTH);
+    const Square Right = (Us == WHITE ? NORTH_EAST : SOUTH_WEST);
+    const Square Left  = (Us == WHITE ? NORTH_WEST : SOUTH_EAST);
 
     Bitboard b, neighbours, stoppers, doubled, supported, phalanx;
     Square s;
@@ -105,10 +106,10 @@ namespace {
     Bitboard ourPawns   = pos.pieces(Us  , PAWN);
     Bitboard theirPawns = pos.pieces(Them, PAWN);
 
-    e->passedPawns[Us] = e->pawnAttacksSpan[Us] = 0;
-    e->kingSquares[Us] = SQ_NONE;
+    e->passedPawns[Us]   = e->pawnAttacksSpan[Us] = 0;
     e->semiopenFiles[Us] = 0xFF;
-    e->pawnAttacks[Us] = shift_bb<Right>(ourPawns) | shift_bb<Left>(ourPawns);
+    e->kingSquares[Us]   = SQ_NONE;
+    e->pawnAttacks[Us]   = shift<Right>(ourPawns) | shift<Left>(ourPawns);
     e->pawnsOnSquares[Us][BLACK] = popcount(ourPawns & DarkSquares);
     e->pawnsOnSquares[Us][WHITE] = pos.count<PAWN>(Us) - e->pawnsOnSquares[Us][BLACK];
 
@@ -119,14 +120,14 @@ namespace {
 
         File f = file_of(s);
 
-        e->semiopenFiles[Us] &= ~(1 << f);
+        e->semiopenFiles[Us]   &= ~(1 << f);
         e->pawnAttacksSpan[Us] |= pawn_attack_span(Us, s);
 
         // Flag the pawn
         opposed    = theirPawns & forward_bb(Us, s);
         stoppers   = theirPawns & passed_pawn_mask(Us, s);
         lever      = theirPawns & pawnAttacksBB[s];
-        doubled    = ourPawns   & forward_bb(Us, s);
+        doubled    = ourPawns   & (s + Up);
         neighbours = ourPawns   & adjacent_files_bb(f);
         phalanx    = neighbours & rank_bb(s);
         supported  = neighbours & rank_bb(s - Up);
@@ -144,15 +145,14 @@ namespace {
             // The pawn is backward when it cannot safely progress to that rank:
             // either there is a stopper in the way on this rank, or there is a
             // stopper on adjacent file which controls the way to that rank.
-            backward = (b | shift_bb<Up>(b & adjacent_files_bb(f))) & stoppers;
-            
+            backward = (b | shift<Up>(b & adjacent_files_bb(f))) & stoppers;
+
             assert(!backward || !(pawn_attack_span(Them, s + Up) & neighbours));
         }
 
         // Passed pawns will be properly scored in evaluation because we need
-        // full attack info to evaluate them. Only the frontmost passed
-        // pawn on each file is considered a true passed pawn.
-        if (!(stoppers | doubled))
+        // full attack info to evaluate them.
+        if (!stoppers && !(ourPawns & forward_bb(Us, s)))
             e->passedPawns[Us] |= s;
 
         // Score this pawn
@@ -169,15 +169,12 @@ namespace {
             score += Connected[opposed][!!phalanx][more_than_one(supported)][relative_rank(Us, s)];
 
         if (doubled)
-            score -= Doubled[f] / distance<Rank>(s, frontmost_sq(Us, doubled));
+            score -= Doubled;
 
         if (lever)
             score += Lever[relative_rank(Us, s)];
     }
 
-    b = e->semiopenFiles[Us] ^ 0xFF;
-    e->pawnSpan[Us] = b ? int(msb(b) - lsb(b)) : 0;
-
     return score;
   }
 
@@ -189,8 +186,8 @@ namespace Pawns {
 /// hard-coded tables, when makes sense, we prefer to calculate them with a formula
 /// to reduce independent parameters and to allow easier tuning and better insight.
 
-void init()
-{
+void init() {
+
   static const int Seed[RANK_NB] = { 0, 8, 19, 13, 71, 94, 169, 324 };
 
   for (int opposed = 0; opposed <= 1; ++opposed)
@@ -221,6 +218,7 @@ Entry* probe(const Position& pos) {
   e->key = key;
   e->score = evaluate<WHITE>(pos, e) - evaluate<BLACK>(pos, e);
   e->asymmetry = popcount(e->semiopenFiles[WHITE] ^ e->semiopenFiles[BLACK]);
+  e->openFiles = popcount(e->semiopenFiles[WHITE] & e->semiopenFiles[BLACK]);
   return e;
 }