sort evasion ahead of time

official-stockfish · Nov 25, 2024 · b3481ab · b3481ab
1 parent b7f1734
commit b3481ab
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Showing 2 changed files with 11 additions and 21 deletions.
diff --git a/src/movepick.cpp b/src/movepick.cpp
@@ -199,19 +199,13 @@ void MovePicker::score() {
 
 // Returns the next move satisfying a predicate function.
 // This never returns the TT move, as it was emitted before.
-template<MovePicker::PickType T, typename Pred>
+template<typename Pred>
 Move MovePicker::select(Pred filter) {
 
-    while (cur < endMoves)
-    {
-        if constexpr (T == Best)
-            std::swap(*cur, *std::max_element(cur, endMoves));
-
+    for (; cur < endMoves; ++cur)
         if (*cur != ttMove && filter())
             return *cur++;
 
-        cur++;
-    }
     return Move::none();
 }
 
@@ -245,7 +239,7 @@ Move MovePicker::next_move() {
         goto top;
 
     case GOOD_CAPTURE :
-        if (select<Next>([&]() {
+        if (select([&]() {
                 // Move losing capture to endBadCaptures to be tried later
                 return pos.see_ge(*cur, -cur->value / 18) ? true
                                                           : (*endBadCaptures++ = *cur, false);
@@ -269,7 +263,7 @@ Move MovePicker::next_move() {
         [[fallthrough]];
 
     case GOOD_QUIET :
-        if (!skipQuiets && select<Next>([]() { return true; }))
+        if (!skipQuiets && select([]() { return true; }))
         {
             if ((cur - 1)->value > -7998 || (cur - 1)->value <= quiet_threshold(depth))
                 return *(cur - 1);
@@ -286,7 +280,7 @@ Move MovePicker::next_move() {
         [[fallthrough]];
 
     case BAD_CAPTURE :
-        if (select<Next>([]() { return true; }))
+        if (select([]() { return true; }))
             return *(cur - 1);
 
         // Prepare the pointers to loop over the bad quiets
@@ -298,7 +292,7 @@ Move MovePicker::next_move() {
 
     case BAD_QUIET :
         if (!skipQuiets)
-            return select<Next>([]() { return true; });
+            return select([]() { return true; });
 
         return Move::none();
 
@@ -307,17 +301,18 @@ Move MovePicker::next_move() {
         endMoves = generate<EVASIONS>(pos, cur);
 
         score<EVASIONS>();
+        partial_insertion_sort(cur, endMoves, std::numeric_limits<int>::min());
         ++stage;
         [[fallthrough]];
 
     case EVASION :
-        return select<Best>([]() { return true; });
+        return select([]() { return true; });
 
     case PROBCUT :
-        return select<Next>([&]() { return pos.see_ge(*cur, threshold); });
+        return select([&]() { return pos.see_ge(*cur, threshold); });
 
     case QCAPTURE :
-        return select<Next>([]() { return true; });
+        return select([]() { return true; });
     }
 
     assert(false);

diff --git a/src/movepick.h b/src/movepick.h
@@ -35,11 +35,6 @@ class Position;
 // a cut-off first.
 class MovePicker {
 
-    enum PickType {
-        Next,
-        Best
-    };
-
    public:
     MovePicker(const MovePicker&)            = delete;
     MovePicker& operator=(const MovePicker&) = delete;
@@ -57,7 +52,7 @@ class MovePicker {
     void skip_quiet_moves();
 
    private:
-    template<PickType T, typename Pred>
+    template<typename Pred>
     Move select(Pred);
     template<GenType>
     void     score();