X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fpawns.cpp;h=4c2ff3913d50faecad5cbc081e5e6b27428cb45a;hp=7eb584d2e8f37c5c8e49b507515bc7ba2c0657d5;hb=76777b663a5f5a2dcfaafa19c15d02d11c401bdf;hpb=ea5505821dabb70eb01cc25f7b4489b0fdc17d2b

diff --git a/src/pawns.cpp b/src/pawns.cpp
index 7eb584d2..4c2ff391 100644
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -18,7 +18,6 @@
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#include <algorithm>
 #include <cassert>
 
 #include "bitboard.h"
@@ -36,8 +35,8 @@ namespace {
   constexpr Score Doubled  = S(11, 56);
   constexpr Score Isolated = S( 5, 15);
 
-  // Connected pawn bonus by opposed, phalanx, #support and rank
-  Score Connected[2][2][3][RANK_NB];
+  // Connected pawn bonus
+  constexpr int Connected[RANK_NB] = { 0, 13, 17, 24, 59, 96, 171 };
 
   // Strength of pawn shelter for our king by [distance from edge][rank].
   // RANK_1 = 0 is used for files where we have no pawn, or pawn is behind our king.
@@ -78,7 +77,6 @@ namespace {
     Bitboard theirPawns = pos.pieces(Them, PAWN);
 
     e->passedPawns[Us] = e->pawnAttacksSpan[Us] = e->weakUnopposed[Us] = 0;
-    e->semiopenFiles[Us] = 0xFF;
     e->kingSquares[Us]   = SQ_NONE;
     e->pawnAttacks[Us]   = pawn_attacks_bb<Us>(ourPawns);
     e->pawnsOnSquares[Us][BLACK] = popcount(ourPawns & DarkSquares);
@@ -90,8 +88,8 @@ namespace {
         assert(pos.piece_on(s) == make_piece(Us, PAWN));
 
         File f = file_of(s);
+        Rank r = relative_rank(Us, s);
 
-        e->semiopenFiles[Us]   &= ~(1 << f);
         e->pawnAttacksSpan[Us] |= pawn_attack_span(Us, s);
 
         // Flag the pawn
@@ -118,8 +116,7 @@ namespace {
             && popcount(phalanx) >= popcount(leverPush))
             e->passedPawns[Us] |= s;
 
-        else if (   stoppers == SquareBB[s + Up]
-                 && relative_rank(Us, s) >= RANK_5)
+        else if (stoppers == square_bb(s + Up) && r >= RANK_5)
         {
             b = shift<Up>(support) & ~theirPawns;
             while (b)
@@ -129,8 +126,11 @@ namespace {
 
         // Score this pawn
         if (support | phalanx)
-            score += Connected[opposed][bool(phalanx)][popcount(support)][relative_rank(Us, s)];
-
+        {
+            int v = (phalanx ? 3 : 2) * Connected[r];
+            v = 17 * popcount(support) + (v >> (opposed + 1));
+            score += make_score(v, v * (r - 2) / 4);
+        }
         else if (!neighbours)
             score -= Isolated, e->weakUnopposed[Us] += !opposed;
 
@@ -148,27 +148,6 @@ namespace {
 
 namespace Pawns {
 
-/// Pawns::init() initializes some tables needed by evaluation. Instead of using
-/// 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() {
-
-  static constexpr int Seed[RANK_NB] = { 0, 13, 24, 18, 65, 100, 175, 330 };
-
-  for (int opposed = 0; opposed <= 1; ++opposed)
-      for (int phalanx = 0; phalanx <= 1; ++phalanx)
-          for (int support = 0; support <= 2; ++support)
-              for (Rank r = RANK_2; r < RANK_8; ++r)
-  {
-      int v = 17 * support;
-      v += (Seed[r] + (phalanx ? (Seed[r + 1] - Seed[r]) / 2 : 0)) >> opposed;
-
-      Connected[opposed][phalanx][support][r] = make_score(v, v * (r - 2) / 4);
-  }
-}
-
-
 /// Pawns::probe() looks up the current position's pawns configuration in
 /// the pawns hash table. It returns a pointer to the Entry if the position
 /// is found. Otherwise a new Entry is computed and stored there, so we don't
@@ -185,8 +164,6 @@ Entry* probe(const Position& pos) {
   e->key = key;
   e->scores[WHITE] = evaluate<WHITE>(pos, e);
   e->scores[BLACK] = evaluate<BLACK>(pos, e);
-  e->asymmetry = popcount(  (e->passedPawns[WHITE]   | e->passedPawns[BLACK])
-                          | (e->semiopenFiles[WHITE] ^ e->semiopenFiles[BLACK]));
 
   return e;
 }
@@ -209,7 +186,7 @@ Value Entry::evaluate_shelter(const Position& pos, Square ksq) {
   Value safety = (shift<Down>(theirPawns) & (FileABB | FileHBB) & BlockRanks & ksq) ?
                  Value(374) : Value(5);
 
-  File center = std::max(FILE_B, std::min(FILE_G, file_of(ksq)));
+  File center = clamp(file_of(ksq), FILE_B, FILE_G);
   for (File f = File(center - 1); f <= File(center + 1); ++f)
   {
       b = ourPawns & file_bb(f);