Eval mobility/pseudo-mobility tweaks; drop unproductive move-ordering experiments.

eval.c: add bishop/rook x-ray pseudo-mobility terms (squares seen past a
directly-attacked higher-value piece), trim pawn-centrality edge penalty
and bishop-pair bonus.

chess.h/dynamic.c/generate.c/search.c/searchsup.c: revert three move-ordering
experiments (recapture bonus, flee-to-safety GOOD_MOVE promotion, ply-2
move-pair bonus) that calibrated with real fail-high signal but never
converted into a measurable node-count or solve-rate win on the curated
suites -- see MOVE_ORDERING_IDEAS.md for the evidence and reasoning behind
each drop. Add MOVE_ORDERING_EVIDENCE_COLLECTION as its own GNUmakefile
flag, independent of PERF_COUNTERS, for any future such harness.

command.c: remove the KING_DEFECT_DUMP-gated evalkingdump command, dead
since the king-safety remine work moved to eval_tune/king_safety_data/.

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

1 files changed, 32 insertions, 6 deletions

diff --git a/src/generate.c b/src/generate.c
index fdfdc79..d202384 100644
--- a/src/generate.c
+++ b/src/generate.c
@@ -908,7 +908,7 @@ GenerateWhiteKnight(IN MOVE_STACK *pStack,
 // ASSERT(pStack->bbOccupied == _BuildFullOccupiedBB(pos)) calls
 // below) and for testgenerate.c's benchmark harness. Non-static so
 // both of those can call it directly.
-BITBOARD
+BITBOARD FORCEINLINE
 _BuildFullOccupiedBB(IN POSITION *pos)
 /**
 
@@ -1004,7 +1004,7 @@ _ComputeCheckTargetMaskBB(IN COOR cKing, IN COOR cAttacker,
 // Non-static so testgenerate.c's harness can call it directly to set
 // up MOVE_STACK.bbFriendlyOccupied when calling a _Generate*BB
 // function outside of _GenerateAllMoves.
-BITBOARD INLINE
+BITBOARD FORCEINLINE
 _BuildFriendlySideBB(IN POSITION *pos, IN ULONG uSide)
 /**
 
@@ -4833,10 +4833,18 @@ Return value:
                     s -= PIECE_VALUE_OVER_100(mv.pMoved);
                     s += SORT_THESE_FIRST;
 
-                    //
-                    // IDEA: bonus for capturing opponent's last moved
-                    // piece to encourage quicker fail highs?
-                    //
+                    // DROPPED: recapture bonus (MOVE_ORDERING_IDEAS.md
+                    // item 4) -- a real, well-calibrated FH% signal
+                    // (64-65% vs. a 49-52% all-captures-at-the-same-
+                    // SEE-sign baseline) that never converted into a
+                    // tree-size win at two magnitudes tried (50: a
+                    // dominant override of MVV/LVA's own ~16-unit
+                    // spread, confirmed real tactical loss on
+                    // ecm_hard_quick; 4: fixed the regression but
+                    // still no node-count improvement on any suite).
+                    // See chess.h's DROPPED comment near
+                    // COUNTERMOVE_EVIDENCE_THRESHOLD for the full
+                    // backlog history.
                     ASSERT(s >= SORT_THESE_FIRST);
                     ASSERT(s > 0);
                     ASSERT((s & STRIP_OFF_FLAGS) < VALUE_KING);
@@ -4899,6 +4907,24 @@ Return value:
                         s |= COUNTERMOVE_TIER_BONUS;
                     }
                 }
+
+                // DROPPED: flee-to-safety tier (MOVE_ORDERING_IDEAS.md
+                // item 6) -- a real, well-calibrated FH% signal
+                // (56-68% vs. ~1.35-1.54% baseline at evidence >=
+                // 10000) that turned out to fire too rarely (2,444-
+                // 9,209 qualifying tries across an entire suite run)
+                // to register any measurable node-count or solve-count
+                // effect either way. See chess.h's DROPPED comment
+                // near COUNTERMOVE_EVIDENCE_THRESHOLD for the full
+                // backlog history.
+
+                // DROPPED: ply-2 move-pair match (MOVE_ORDERING_IDEAS.md
+                // item 3) -- a real, well-calibrated signal (53-66% FH
+                // vs. ~1.2-1.4% baseline) that never converted into a
+                // tree-size win across three mechanisms tried (tier
+                // escape, dominant nudge, proportionate nudge). See
+                // chess.h's DROPPED comment near COUNTERMOVE_EVIDENCE_
+                // THRESHOLD for the full history.
                 ASSERT(s >= 0);
             }
             pStack->mvf[u].iValue = s;