Revert "Better handle dynamic pruning when the leading clause has a s…

…ingle impact block. (apache#13904)"

This reverts commit 5fd4525.

lucene/CHANGES.txt

@@ -53,10 +53,6 @@ Optimizations
 * GITHUB#13800: MaxScoreBulkScorer now recomputes scorer partitions when the
   minimum competitive allows for a more favorable partitioning. (Adrien Grand)
 
-* GITHUB#13904: BlockMaxConjunctionBulkScorer can now early exit when the
-  leading clause has a single impact block (e.g. ConstantScoreQuery).
-  (Adrien Grand)
-
 Bug Fixes
 ---------------------
 * GITHUB#13832: Fixed an issue where the DefaultPassageFormatter.format method did not format passages as intended

lucene/core/src/java/org/apache/lucene/search/BlockMaxConjunctionBulkScorer.java

@@ -85,20 +85,9 @@ public int score(LeafCollector collector, Bits acceptDocs, int min, int max) thr
 
     int windowMin = Math.max(lead1.docID(), min);
     while (windowMin < max) {
-      // Use impacts of the least costly scorer to compute windows to keep the per-block overhead
-      // under control.
-      // NOTE: windowMax is inclusive.
-      int windowMax = scorer1.advanceShallow(windowMin);
-      if (windowMax == DocIdSetIterator.NO_MORE_DOCS) {
-        // If the query doesn't have impacts anymore, or has a single block for the whole doc ID
-        // space (e.g. ConstantScoreQuery), then we try to create a block that has ~128 docs of the
-        // leading clause. This gives us higher chances to exit early based on the maximum scores of
-        // other clauses.
-        long windowSize = 128L * maxDoc / Math.max(1, lead1.cost());
-        windowSize = Math.max(windowSize, 128L);
-        windowMax = (int) Math.min(Integer.MAX_VALUE, windowMin + windowSize);
-      }
-      windowMax = Math.min(windowMax, max - 1);
+      // Use impacts of the least costly scorer to compute windows
+      // NOTE: windowMax is inclusive
+      int windowMax = Math.min(scorers[0].advanceShallow(windowMin), max - 1);
 
       float maxWindowScore = Float.POSITIVE_INFINITY;
       if (0 < scorable.minCompetitiveScore) {