Prevent eternal loop if bit vectors are shorter than docid limit

3 files changed, 8 insertions, 8 deletions

diff --git a/searchlib/src/tests/queryeval/multibitvectoriterator/multibitvectoriterator_test.cpp b/searchlib/src/tests/queryeval/multibitvectoriterator/multibitvectoriterator_test.cpp
index dd3394db507..23f77a9d9d9 100644
--- a/searchlib/src/tests/queryeval/multibitvectoriterator/multibitvectoriterator_test.cpp
+++ b/searchlib/src/tests/queryeval/multibitvectoriterator/multibitvectoriterator_test.cpp
@@ -578,7 +578,7 @@ createDual(Fixture & f, TermFieldMatchData & tfmd, int32_t docIdLimit) {
     MultiSearch::Children children;
     children.push_back(f.createIter(0, false, tfmd, true));
     children.push_back(f.createIter(1, false, tfmd, true));
-    SearchIterator::UP s = AndSearch::create(std::move(children), false);
+    SearchIterator::UP s = AndSearch::create(std::move(children), true);
     s = MultiBitVectorIteratorBase::optimize(std::move(s));
     EXPECT_TRUE(s);
     if (docIdLimit < 0) {
@@ -612,12 +612,11 @@ TEST_F("test that short vectors don't spin at end", Fixture) {
     countUntilEnd(*createDual(f, tfmd, f._bvs[0]->size()));
     countUntilDocId(*createDual(f, tfmd, f._bvs[0]->size()));
 
-    // Below fails with eternal loop
-    //countUntilDocId(*createDual(f, tfmd, f._bvs[0]->size() + 1));
-    //countUntilEnd(*createDual(f, tfmd, f._bvs[0]->size() + 1));
+    countUntilDocId(*createDual(f, tfmd, f._bvs[0]->size() + 1));
+    countUntilEnd(*createDual(f, tfmd, f._bvs[0]->size() + 1));
 
-    //countUntilDocId(*createDual(f, tfmd, -1));
-    //countUntilEnd(*createDual(f, tfmd, -1));
+    countUntilDocId(*createDual(f, tfmd, -1));
+    countUntilEnd(*createDual(f, tfmd, -1));
 }
 
 class Verifier : public search::test::SearchIteratorVerifier {
diff --git a/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.cpp b/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.cpp
index 6408004ea32..563a88e860f 100644
--- a/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.cpp
+++ b/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.cpp
@@ -66,7 +66,7 @@ bool
 MultiBitVector<Update>::updateLastValue(uint32_t docId) noexcept
 {
     if (docId >= _lastMaxDocIdLimit) {
-        if (__builtin_expect(docId >= _numDocs, false)) {
+        if (__builtin_expect(isAtEnd(docId), false)) {
             return true;
         }
         const uint32_t index(BitWord::wordNum(docId));
@@ -147,7 +147,7 @@ public:
 private:
     void doSeek(uint32_t docId) override {
         docId = this->_mbv.strictSeek(docId);
-        if (__builtin_expect(docId >= this->getEndId(), false)) {
+        if (__builtin_expect(this->_mbv.isAtEnd(docId), false)) {
             this->setAtEnd();
         } else {
             this->setDocId(docId);
diff --git a/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.h b/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.h
index 5c3d17c6786..855ecfae60c 100644
--- a/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.h
+++ b/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.h
@@ -19,6 +19,7 @@ public:
         _lastMaxDocIdLimit = 0;
         _lastMaxDocIdLimitRequireFetch = 0;
     }
+    bool isAtEnd(uint32_t docId) const noexcept { return docId >= _numDocs; }
     void addBitVector(Meta bv, uint32_t docIdLimit);
 protected:
     uint32_t            _numDocs;