Lift out single iterators if they are leafs and tfmd is not needed.

2 files changed, 9 insertions, 3 deletions

diff --git a/searchlib/src/vespa/searchlib/queryeval/blueprint.h b/searchlib/src/vespa/searchlib/queryeval/blueprint.h
index 8d230b6ec01..882db00c059 100644
--- a/searchlib/src/vespa/searchlib/queryeval/blueprint.h
+++ b/searchlib/src/vespa/searchlib/queryeval/blueprint.h
@@ -251,6 +251,7 @@ public:
     virtual bool isEquiv() const { return false; }
     virtual bool isWhiteList() const { return false; }
     virtual bool isIntermediate() const { return false; }
+    virtual bool isLeaf() const { return false; }
     virtual bool isAnd() const { return false; }
     virtual bool isAndNot() const { return false; }
     virtual bool isOr() const { return false; }
@@ -396,6 +397,7 @@ public:
     void fetchPostings(const ExecuteInfo &execInfo) override;
     void freeze() final;
     SearchIteratorUP createSearch(fef::MatchData &md, bool strict) const override;
+    bool isLeaf() const final { return true; }
 
     virtual bool getRange(vespalib::string & from, vespalib::string & to) const;
     virtual SearchIteratorUP createLeafSearch(const fef::TermFieldMatchDataArray &tfmda, bool strict) const = 0;
diff --git a/searchlib/src/vespa/searchlib/queryeval/weighted_set_term_blueprint.cpp b/searchlib/src/vespa/searchlib/queryeval/weighted_set_term_blueprint.cpp
index 55009e714b9..f09ad4103d8 100644
--- a/searchlib/src/vespa/searchlib/queryeval/weighted_set_term_blueprint.cpp
+++ b/searchlib/src/vespa/searchlib/queryeval/weighted_set_term_blueprint.cpp
@@ -96,11 +96,15 @@ SearchIterator::UP
 WeightedSetTermBlueprint::createLeafSearch(const fef::TermFieldMatchDataArray &tfmda, bool) const
 {
     assert(tfmda.size() == 1);
+    if ((_terms.size() == 1) && tfmda[0]->isNotNeeded() && _terms[0]->isLeaf()) {
+        return static_cast<LeafBlueprint &>(*_terms[0]).createLeafSearch(tfmda, true);
+    }
     fef::MatchData::UP md = _layout.createMatchData();
-    std::vector<SearchIterator*> children(_terms.size());
-    for (size_t i = 0; i < _terms.size(); ++i) {
+    std::vector<SearchIterator*> children;
+    children.reserve(_terms.size());
+    for (const auto & _term : _terms) {
         // TODO: pass ownership with unique_ptr
-        children[i] = _terms[i]->createSearch(*md, true).release();
+        children.push_back(_term->createSearch(*md, true).release());
     }
     return WeightedSetTermSearch::create(children, *tfmda[0], _children_field.isFilter(), _weights, std::move(md));
 }