- Separate hot/cold path to enable compiler to make an even leaner hot path.

2 files changed, 20 insertions, 14 deletions

diff --git a/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.cpp b/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.cpp
index fdf4ec950dd..331f01d4a82 100644
--- a/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.cpp
+++ b/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.cpp
@@ -63,24 +63,24 @@ MultiBitVector<Update>::MultiBitVector(size_t reserved)
 
 template<typename Update>
 bool
-MultiBitVector<Update>::updateLastValue(uint32_t docId) noexcept
+MultiBitVector<Update>::updateLastValueCold(uint32_t docId) noexcept
 {
-    if (docId >= _lastMaxDocIdLimit) {
-        if (__builtin_expect(isAtEnd(docId), false)) {
-            return true;
-        }
-        const uint32_t index(BitWord::wordNum(docId));
-        if (docId >= _lastMaxDocIdLimitRequireFetch) {
-            uint32_t baseIndex = index & ~(NumWordsInBatch - 1);
-            _update(_accel, baseIndex*sizeof(Word), _bvs, _lastWords);
-            _lastMaxDocIdLimitRequireFetch = (baseIndex + NumWordsInBatch) * BitWord::WordLen;
-        }
-        _lastValue = _lastWords[index % NumWordsInBatch];
-        _lastMaxDocIdLimit = (index + 1) * BitWord::WordLen;
+    if (__builtin_expect(isAtEnd(docId), false)) {
+        return true;
     }
+    const uint32_t index(BitWord::wordNum(docId));
+    if (docId >= _lastMaxDocIdLimitRequireFetch) {
+        uint32_t baseIndex = index & ~(NumWordsInBatch - 1);
+        _update(_accel, baseIndex*sizeof(Word), _bvs, _lastWords);
+        _lastMaxDocIdLimitRequireFetch = (baseIndex + NumWordsInBatch) * BitWord::WordLen;
+    }
+    _lastValue = _lastWords[index % NumWordsInBatch];
+    _lastMaxDocIdLimit = (index + 1) * BitWord::WordLen;
     return false;
 }
 
+
+
 template<typename Update>
 uint32_t
 MultiBitVector<Update>::strictSeek(uint32_t docId) noexcept
diff --git a/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.h b/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.h
index 2b4f90544ac..66598e28e3e 100644
--- a/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.h
+++ b/searchlib/src/vespa/searchlib/queryeval/multibitvectoriterator.h
@@ -37,7 +37,13 @@ public:
     bool seek(uint32_t docId) noexcept;
     bool acceptExtraFilter() const noexcept { return Update::isAnd(); }
 private:
-    bool updateLastValue(uint32_t docId) noexcept;
+    bool updateLastValue(uint32_t docId) noexcept {
+        if (docId >= _lastMaxDocIdLimit) {
+            return updateLastValueCold(docId);
+        }
+        return false;
+    }
+    VESPA_DLL_LOCAL bool updateLastValueCold(uint32_t docId) noexcept __attribute__((noinline));
     using IAccelrated = vespalib::hwaccelrated::IAccelrated;
 
     Update              _update;