Minor changes and file permissions.HEADmaster

1 files changed, 33 insertions, 53 deletions

diff --git a/src/eval.c b/src/eval.c
index 5522d2d..26b7ace 100755..100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -1261,10 +1261,12 @@ Return value:
 {
     COOR c1, cSquare;
     PIECE pSentry, pHelper;
-    ULONG uPawnFile = FILE(c) + 1;
+    ULONG ucFile = FILE(c);
+    ULONG uPawnFile = ucFile + 1;
     BITBOARD bb;
     ULONG uSentries, uHelpers;
     ULONG uColor;
+    ULONG xColor;
     int d1;
 #ifdef DEBUG
     COOR cVerifySquare;
@@ -1278,54 +1280,49 @@ Return value:
     ASSERT(IS_PAWN(pHelper));
     uColor = GET_COLOR(pHelper);
     ASSERT(IS_VALID_COLOR(uColor));
+    xColor = FLIP(uColor);
 
-    if (pHash->uCountPerFile[FLIP(uColor)][uPawnFile] != 0)
+    // The only way a pawn can be a passer/candidate if the other
+    // side has a pawn on its same file is if that enemy pawn is
+    // behind it.  This is a corner case but it is important to
+    // detect all passers.
+    if (pHash->uCountPerFile[xColor][uPawnFile] != 0)
     {
-        ASSERT((pos->bbPawns[FLIP(uColor)] & BBFILE[FILE(c)]) != 0);
-
-        //
-        // The only way a pawn can be a passer/candidate if the other
-        // side has a pawn on its same file is if that enemy pawn is
-        // behind it.  This is a corner case but it is important to
-        // detect all passers.
-        //
+        ASSERT((pos->bbPawns[xColor] & BBFILE[ucFile]) != 0);
         switch(uColor)
         {
             case WHITE:
-                bb = pos->bbPawns[BLACK] & BBFILE[FILE(c)];
+                bb = pos->bbPawns[BLACK] & BBFILE[ucFile];
                 ASSERT(bb);
                 while(IS_ON_BOARD(c1 = CoorFromBitBoardRank8ToRank1(&bb)))
                 {
-                    ASSERT(FILE(c1) == FILE(c));
+                    ASSERT(FILE(c1) == ucFile);
                     if (c1 < c) return;
                 }
                 break;
             case BLACK:
-                bb = pos->bbPawns[WHITE] & BBFILE[FILE(c)];
+                bb = pos->bbPawns[WHITE] & BBFILE[ucFile];
                 ASSERT(bb);
                 while(IS_ON_BOARD(c1 = CoorFromBitBoardRank1ToRank8(&bb)))
                 {
-                    ASSERT(FILE(c1) == FILE(c));
+                    ASSERT(FILE(c1) == ucFile);
                     if (c1 > c) return;
                 }
                 break;
         }
     }
 
-    //
-    // Count FLIP(uColor)'s sentries and determine the location of the
-    // critical square.  Note if there are no sentries then this
-    // pawn (on square c) is a passer already, not a candidate.
-    //
-    bb = pos->bbPawns[FLIP(uColor)] & BBADJACENT_FILES[FILE(c)];
+    // Count xColor's sentry pawns and determine the location of the
+    // critical square for the pawn at c to become a passer.  Note if
+    // there are no sentries then this pawn (on square c) is a passer
+    // already, not a candidate.
+    bb = pos->bbPawns[xColor] & BBADJACENT_FILES[ucFile];
     bb &= BBPRECEEDING_RANKS[(c & 0x70) >> 4][uColor];
     if (!bb)
     {
         ASSERT(CountBits(bb) == 0);
 
-        //
-        // There are no sentries so this pawn is a passer.
-        //
+        // There are no enemy sentries so this pawn is a passer.
         pHash->bbPasserLocations[uColor] |= COOR_TO_BB(c);
         ASSERT(CountBits(pHash->bbPasserLocations[uColor]) > 0);
         ASSERT(CountBits(pHash->bbPasserLocations[uColor]) <= 8);
@@ -1336,9 +1333,7 @@ Return value:
                   PASSER_BY_RANK[uColor][RANK(c)],
                   "passed pawn");
 
-        //
         // However, don't give doubled passers such a big bonus.
-        //
         if (IS_PAWN(pos->rgSquare[c - 16 * g_iAhead[uColor]].pPiece))
         {
             EVAL_TERM(uColor,
@@ -1352,10 +1347,10 @@ Return value:
     }
     uSentries = CountBits(bb);
 
-    //
-    // There's one or more sentry pawns so we'll look for helpers to
-    // decide if this pawn is a candidate passer.
-    //
+    // There's one or more sentry pawns so we'll look for friendly
+    // helpers to decide if this pawn is a candidate passer.  First
+    // figure out the critical square we need to get the passer
+    // through.
     if (uColor == WHITE)
     {
         pSentry = BLACK_PAWN;
@@ -1369,9 +1364,9 @@ Return value:
         cSquare -= 0x10;
     }
     cSquare &= 0xF0;
-    cSquare |= FILE(c);
+    cSquare |= ucFile;
     ASSERT(IS_ON_BOARD(cSquare));
-    ASSERT(FILE(cSquare) == FILE(c));
+    ASSERT(FILE(cSquare) == ucFile);
 
 #ifdef DEBUG
     uVerifySentries = 0;
@@ -1443,26 +1438,21 @@ Return value:
     if ((IS_ON_BOARD(c1)) && (pHash->uCountPerFile[uColor][FILE(c1) + 1]))
     {
         ASSERT(pos->bbPawns[uColor] & BBFILE[FILE(c1)]);
-        if (!(pos->bbPawnAttacks[FLIP(uColor)] & COOR_TO_BB(c1)) ||
+        if (!(pos->bbPawnAttacks[xColor] & COOR_TO_BB(c1)) ||
             (pos->bbPawnAttacks[uColor] & COOR_TO_BB(c1)))
         {
-            //
-            // The square c1 the place a helper pawn must get to in
-            // order to aide the candidate past a sentry.
-            //
+            // Friend helper pawn there?
             if (pos->rgSquare[c1].pPiece == pHelper)
             {
                 uHelpers = 1;
                 goto do_left;
             }
 
-            //
             // There is no helper pawn in the support position yet.
             // See if one can get there.
-            //
             c1 = c1 - d1;
             while (IS_ON_BOARD(c1) &&
-                   ((!(pos->bbPawnAttacks[FLIP(uColor)] & COOR_TO_BB(c1))) ||
+                   ((!(pos->bbPawnAttacks[xColor] & COOR_TO_BB(c1))) ||
                     (pos->bbPawnAttacks[uColor] & COOR_TO_BB(c1))))
             {
                 if (pos->rgSquare[c1].pPiece == pHelper)
@@ -1485,26 +1475,21 @@ Return value:
     {
         ASSERT(pos->bbPawns[uColor] & BBFILE[FILE(c1)]);
 
-        if (!(pos->bbPawnAttacks[FLIP(uColor)] & COOR_TO_BB(c1)) ||
+        if (!(pos->bbPawnAttacks[xColor] & COOR_TO_BB(c1)) ||
             (pos->bbPawnAttacks[uColor] & COOR_TO_BB(c1)))
         {
-            //
-            // The square c1 is the place a helper pawn must get to in
-            // order to aide the candidate.
-            //
+            // Already a helper there?
             if (pos->rgSquare[c1].pPiece == pHelper)
             {
                 uHelpers++;
                 goto done_helpers;
             }
 
-            //
             // There is no pawn in the left support position yet.  See
             // if one can get there.
-            //
             c1 -= d1;
             while (IS_ON_BOARD(c1) &&
-                   ((!(pos->bbPawnAttacks[FLIP(uColor)] & COOR_TO_BB(c1))) ||
+                   ((!(pos->bbPawnAttacks[xColor] & COOR_TO_BB(c1))) ||
                     (pos->bbPawnAttacks[uColor] & COOR_TO_BB(c1))))
             {
                 if (pos->rgSquare[c1].pPiece == pHelper)
@@ -1536,14 +1521,12 @@ Return value:
                   CANDIDATE_PASSER_BY_RANK[uColor][RANK(c)],
                   "candidate passer");
 
-        //
         // If the other side has no pieces then give this candidate an
         // extra bonus -- used to be a second full copy of the same
         // CANDIDATE_PASSER_BY_RANK value (an exact duplicate of the
         // term just added above, not a different angle on it), now a
         // fractional modifier.
-        //
-        if (pos->uNonPawnCount[FLIP(uColor)][0] == 1)
+        if (pos->uNonPawnCount[xColor][0] == 1)
         {
             EVAL_TERM(uColor,
                       PAWN,
@@ -1588,7 +1571,6 @@ Return value:
     FOREACH_COLOR(uColor)
     {
         ASSERT(IS_VALID_COLOR(uColor));
-
         if (pHash->bbPasserLocations[uColor])
         {
             ASSERT(pos->uPawnCount[uColor] > 0);
@@ -1602,10 +1584,8 @@ Return value:
                     ASSERT(pHash->uCountPerFile[uColor][u+1] != 0);
                     while(IS_ON_BOARD(c = CoorFromBitBoardRank8ToRank1(&bb)))
                     {
-                        //
                         // Keep track of leftmost/rightmost passer for
                         // outside passer code later on.
-                        //
                         ASSERT(FILE(c) == u);
                         ASSERT(RANK(c) > 1);
                         ASSERT(RANK(c) < 8);