- break;
-
- case KILLERS_S1:
- cur = killers;
- endMoves = cur + 2;
-
- killers[0].move = ss->killers[0];
- killers[1].move = ss->killers[1];
- killers[2].move = killers[3].move = MOVE_NONE;
- killers[4].move = killers[5].move = MOVE_NONE;
-
- // In SMP case countermoves[] and followupmoves[] could have duplicated entries
- // in rare cases (less than 1 out of a million). This is harmless.
-
- // Be sure countermoves and followupmoves are different from killers
- for (int i = 0; i < 2; ++i)
- if ( countermoves[i] != killers[0].move
- && countermoves[i] != killers[1].move)
- (endMoves++)->move = countermoves[i];
-
- for (int i = 0; i < 2; ++i)
- if ( followupmoves[i] != killers[0].move
- && followupmoves[i] != killers[1].move
- && followupmoves[i] != killers[2].move
- && followupmoves[i] != killers[3].move)
- (endMoves++)->move = followupmoves[i];
- break;
-
- case QUIETS_1_S1:
- endQuiets = endMoves = generate<QUIETS>(pos, moves);
- score<QUIETS>();
- endMoves = std::partition(cur, endMoves, [](const ExtMove& m) { return m.value > VALUE_ZERO; });
- insertion_sort(cur, endMoves);
- break;
-
- case QUIETS_2_S1:
- cur = endMoves;
- endMoves = endQuiets;
- if (depth >= 3 * ONE_PLY)
- insertion_sort(cur, endMoves);
- break;
-
- case BAD_CAPTURES_S1:
- // Just pick them in reverse order to get MVV/LVA ordering
- cur = moves + MAX_MOVES - 1;
- endMoves = endBadCaptures;
- break;
+ ++stage;
+ goto top;
+
+ case GOOD_CAPTURE:
+ if (select<Best>([&](){
+ return pos.see_ge(*cur, Value(-55 * cur->value / 1024)) ?
+ // Move losing capture to endBadCaptures to be tried later
+ true : (*endBadCaptures++ = *cur, false); }))
+ return *(cur - 1);
+
+ // Prepare the pointers to loop over the refutations array
+ cur = std::begin(refutations);
+ endMoves = std::end(refutations);
+
+ // If the countermove is the same as a killer, skip it
+ if ( refutations[0].move == refutations[2].move
+ || refutations[1].move == refutations[2].move)
+ --endMoves;
+
+ ++stage;
+ /* fallthrough */
+
+ case REFUTATION:
+ if (select<Next>([&](){ return *cur != MOVE_NONE
+ && !pos.capture(*cur)
+ && pos.pseudo_legal(*cur); }))
+ return *(cur - 1);
+ ++stage;
+ /* fallthrough */
+
+ case QUIET_INIT:
+ if (!skipQuiets)
+ {
+ cur = endBadCaptures;
+ endMoves = generate<QUIETS>(pos, cur);
+
+ score<QUIETS>();
+ partial_insertion_sort(cur, endMoves, -4000 * depth / ONE_PLY);
+ }