1 files changed, 7 insertions, 28 deletions

diff --git a/src/mongo/db/matcher/rewrite_expr.h b/src/mongo/db/matcher/rewrite_expr.h
index 08e7d82d23d..1752c9726b8 100644
--- a/src/mongo/db/matcher/rewrite_expr.h
+++ b/src/mongo/db/matcher/rewrite_expr.h
@@ -42,20 +42,14 @@ namespace mongo {
 class RewriteExpr final {
 public:
     /**
-     * Holds the result of an Expression rewrite operation. $expr expressions can't take advantage
-     * of indexes. When we rewrite the expressions as a conjunction of internal match expressions,
-     * the query planner can now use the internal match expressions to potentially generate an index
-     * scan. We use internal match expressions that are non-type bracketed to match non-type
-     * bracketed comparison operators inside $expr.
+     * Holds the result of an Expression rewrite operation.
      */
     class RewriteResult final {
     public:
         RewriteResult(std::unique_ptr<MatchExpression> matchExpression,
-                      std::vector<BSONObj> matchExprElemStorage,
-                      bool allSubExpressionsRewritten)
+                      std::vector<BSONObj> matchExprElemStorage)
             : _matchExpression(std::move(matchExpression)),
-              _matchExprElemStorage(std::move(matchExprElemStorage)),
-              _allSubExpressionsRewritten(allSubExpressionsRewritten) {}
+              _matchExprElemStorage(std::move(matchExprElemStorage)) {}
 
         MatchExpression* matchExpression() const {
             return _matchExpression.get();
@@ -67,11 +61,7 @@ public:
 
         RewriteResult clone() const {
             auto clonedMatch = _matchExpression ? _matchExpression->shallowClone() : nullptr;
-            return {std::move(clonedMatch), _matchExprElemStorage, _allSubExpressionsRewritten};
-        }
-
-        bool allSubExpressionsRewritten() {
-            return _allSubExpressionsRewritten;
+            return {std::move(clonedMatch), _matchExprElemStorage};
         }
 
     private:
@@ -81,22 +71,12 @@ public:
         // owned and expected to outlive the MatchExpression. '_matchExprElemStorage' holds the
         // underlying BSONObj storage for these arguments.
         std::vector<BSONObj> _matchExprElemStorage;
-
-        // Defaults to true, is false if there is a child in an $or/$and expression that
-        // contains children that cannot be rewritten to a MatchExpression.
-        bool _allSubExpressionsRewritten = true;
     };
 
     /**
-     * Attempts to construct a MatchExpression that will match against either an identical set
-     * or a superset of the documents matched by 'expr'. Due to semantic differences the
-     * rewritten MatchExpression might match more documents than the ExprMatchExpression. For
-     * example,
-     * $_internalExprEq in MatchExpression reaches into arrays, and $eq in ExprMatchExpression
-     * does not. However, $_internalExprLt/$_internalExprGt are non-type bracketed for
-     * MatchExpression, just like ExprMatchExpressions. Returns the MatchExpression as a
-     * RewriteResult. If a rewrite is not possible, RewriteResult::matchExpression() will return
-     * a nullptr.
+     * Attempts to construct a MatchExpression that will match against either an identical set or a
+     * superset of the documents matched by 'expr'. Returns the MatchExpression as a RewriteResult.
+     * If a rewrite is not possible, RewriteResult::matchExpression() will return a nullptr.
      */
     static RewriteResult rewrite(const boost::intrusive_ptr<Expression>& expr,
                                  const CollatorInterface* collator);
@@ -127,7 +107,6 @@ private:
 
     std::vector<BSONObj> _matchExprElemStorage;
     const CollatorInterface* _collator;
-    bool _allSubExpressionsRewritten = true;
 };
 
 }  // namespace mongo