Cache good/bad-bishop pawn-structure score in the pawn hash

iBishopColorScore[color][complex] is a pure function of pawn placement
(own/enemy, stationary/transient) on a bishop's color complex, so it
doesn't need rescanning per-bishop -- computed once per pawn-hash miss
in _EvalPawns and reused by every bishop of that color/complex in
_EvalBishop, mirroring the same cache-the-per-structure-invariant idea
already used elsewhere in eval.c.

Also disables two speculative check-extension/futility-gating
experiments in search.c (#if 0, not deleted -- kept for reference)
that didn't hold up, and adds the BBLEFT/BBRIGHT bitboard constants
eval.c's bishop-mobility rewrite needs.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

1 files changed, 24 insertions, 21 deletions

diff --git a/src/search.c b/src/search.c
index ccaae74..e6249b0 100644
--- a/src/search.c
+++ b/src/search.c
@@ -938,6 +938,7 @@ Search(IN SEARCHER_THREAD_CONTEXT *ctx,
                     if (MOVE_COUNT(ctx, ctx->uPly))
                     {
                         // TODO: Experiment with removing these extensions.
+#if 0
                         if (NUM_CHECKING_PIECES(ctx, ctx->uPly) > 1)
                         {
                             iPositionalExtend += QUARTER_PLY;
@@ -948,7 +949,8 @@ Search(IN SEARCHER_THREAD_CONTEXT *ctx,
                             iPositionalExtend += QUARTER_PLY;
                             INC(ctx->sCounters.extension.uNoLegalKingMoves);
                         }
-                        else if (ONE_LEGAL_MOVE(ctx, ctx->uPly) &&
+#endif
+                        if (ONE_LEGAL_MOVE(ctx, ctx->uPly) &&
                                  CountKingSafetyDefects(pos, pos->uToMove) > 2)
                         {
                             iPositionalExtend += HALF_PLY;
@@ -1248,14 +1250,14 @@ Search(IN SEARCHER_THREAD_CONTEXT *ctx,
             // extensions which are represented by iPositionalExtend).
             iExtend = iPositionalExtend;
             ComputeMoveExtension(ctx,
-                                    iAlpha,
-                                    iBeta,
-                                    (x - 1),     // Note: x==0 if doing mvHash
-                                    iEval,
-                                    uDepth,
-                                    iMoveSee,
-                                    fIsLeftoverMove,
-                                    &iExtend);
+                                 iAlpha,
+                                 iBeta,
+                                 (x - 1),     // Note: x==0 if doing mvHash
+                                 iEval,
+                                 uDepth,
+                                 iMoveSee,
+                                 fIsLeftoverMove,
+                                 &iExtend);
 
             ASSERT((uLegalMoves > 1) ? (x != 0) : TRUE);
             fMoveIsPruneReduceEligible = CanWeReduceOrPruneMove(ctx,
@@ -2670,26 +2672,27 @@ _ShouldWeConsiderThisMove(IN SEARCHER_THREAD_CONTEXT *ctx,
         ASSERT(IS_CHECKING_MOVE(mv));
         ASSERT(TRUE == fGeneratedChecks);
 
+#if 0
         // IDEA: don't play obviously losing checks if we are already
         // way below alpha.
         if (iFutility < +VALUE_BISHOP)
         {
             return(TRUE);
         }
-        {
-            FLAG fConsider = (GetMoveSee(ctx, mv, uMoveNum) >= 0);
-#ifdef CALIBRATE_QSEARCH_FUTILITY
-            if (FALSE == fConsider)
-            {
-                _QFutDiagnoseReject(ctx, uMoveNum, iAlpha, iBeta,
-                                    iPositional, uPositionalSource,
-                                    QFUT_GATE_CHECK_BISHOP,
-                                    iFutility - (SCORE)VALUE_BISHOP,
-                                    fGeneratedChecks);
-            }
 #endif
-            return(fConsider);
+        FLAG fConsider = (GetMoveSee(ctx, mv, uMoveNum) >= 0);
+#ifdef CALIBRATE_QSEARCH_FUTILITY
+        if (FALSE == fConsider)
+        {
+            _QFutDiagnoseReject(ctx, uMoveNum, iAlpha, iBeta,
+                                iPositional, uPositionalSource,
+                                QFUT_GATE_CHECK_BISHOP,
+                                iFutility, //  - (SCORE)VALUE_BISHOP,
+                                fGeneratedChecks);
         }
+#endif
+        return(fConsider);
+
     }
     return(FALSE);
 }