enable re-using termwise bitvectors in second phase

detach match data from rank program and refactor match loop
re-use bitvector in termwise search if range is the same

70 files changed, 208 insertions, 126 deletions

diff --git a/searchlib/src/tests/features/item_raw_score/item_raw_score_test.cpp b/searchlib/src/tests/features/item_raw_score/item_raw_score_test.cpp
index f407aea811b..a954710f153 100644
--- a/searchlib/src/tests/features/item_raw_score/item_raw_score_test.cpp
+++ b/searchlib/src/tests/features/item_raw_score/item_raw_score_test.cpp
@@ -67,13 +67,14 @@ struct SingleLabel : public Labels {
 struct RankFixture : BlueprintFactoryFixture, IndexFixture {
     QueryEnvironment         queryEnv;
     RankSetup                rankSetup;
-    RankProgram::UP          rankProgram;
     MatchDataLayout          mdl;
+    MatchData::UP            match_data;
+    RankProgram::UP          rankProgram;
     std::vector<TermFieldHandle> fooHandles;
     std::vector<TermFieldHandle> barHandles;
     RankFixture(size_t fooCnt, size_t barCnt, const Labels &labels)
         : queryEnv(&indexEnv), rankSetup(factory, indexEnv),
-          rankProgram(), mdl(), fooHandles(), barHandles()
+          mdl(), match_data(), rankProgram(), fooHandles(), barHandles()
     {
         for (size_t i = 0; i < fooCnt; ++i) {
             uint32_t fieldId = indexEnv.getFieldByName("foo")->id();
@@ -95,14 +96,15 @@ struct RankFixture : BlueprintFactoryFixture, IndexFixture {
         rankSetup.setFirstPhaseRank(featureName);
         rankSetup.setIgnoreDefaultRankFeatures(true);
         ASSERT_TRUE(rankSetup.compile());
+        match_data = mdl.createMatchData();
         rankProgram = rankSetup.create_first_phase_program();
-        rankProgram->setup(mdl, queryEnv);
+        rankProgram->setup(*match_data, queryEnv);
     }
     feature_t getScore(uint32_t docId) {
         return Utils::getScoreFeature(*rankProgram, docId);
     }
     void setScore(TermFieldHandle handle, uint32_t docId, feature_t score) {
-        rankProgram->match_data().resolveTermField(handle)->setRawScore(docId, score);
+        match_data->resolveTermField(handle)->setRawScore(docId, score);
     }
     void setFooScore(uint32_t i, uint32_t docId, feature_t score) {
         ASSERT_LESS(i, fooHandles.size());
diff --git a/searchlib/src/tests/features/native_dot_product/native_dot_product_test.cpp b/searchlib/src/tests/features/native_dot_product/native_dot_product_test.cpp
index 5ba7504f7d2..1da912ccb3a 100644
--- a/searchlib/src/tests/features/native_dot_product/native_dot_product_test.cpp
+++ b/searchlib/src/tests/features/native_dot_product/native_dot_product_test.cpp
@@ -72,14 +72,15 @@ std::vector<uint32_t> vec(uint32_t w1, uint32_t w2, uint32_t w3) {
 struct RankFixture : BlueprintFactoryFixture, IndexFixture {
     QueryEnvironment         queryEnv;
     RankSetup                rankSetup;
-    RankProgram::UP          rankProgram;
     MatchDataLayout          mdl;
+    MatchData::UP            match_data;
+    RankProgram::UP          rankProgram;
     std::vector<TermFieldHandle> fooHandles;
     std::vector<TermFieldHandle> barHandles;
     RankFixture(const std::vector<uint32_t> &fooWeights,
                 const std::vector<uint32_t> &barWeights)
         : queryEnv(&indexEnv), rankSetup(factory, indexEnv),
-          rankProgram(), mdl(), fooHandles(), barHandles()
+          mdl(), match_data(), rankProgram(), fooHandles(), barHandles()
     {
         for (size_t i = 0; i < fooWeights.size(); ++i) {
             uint32_t fieldId = indexEnv.getFieldByName("foo")->id();
@@ -100,8 +101,9 @@ struct RankFixture : BlueprintFactoryFixture, IndexFixture {
         rankSetup.setFirstPhaseRank(featureName);
         rankSetup.setIgnoreDefaultRankFeatures(true);
         ASSERT_TRUE(rankSetup.compile());
+        match_data = mdl.createMatchData();
         rankProgram = rankSetup.create_first_phase_program();
-        rankProgram->setup(mdl, queryEnv);
+        rankProgram->setup(*match_data, queryEnv);
     }
     feature_t getScore(uint32_t docId) {
         return Utils::getScoreFeature(*rankProgram, docId);
@@ -110,15 +112,15 @@ struct RankFixture : BlueprintFactoryFixture, IndexFixture {
         ASSERT_LESS(i, fooHandles.size());
         TermFieldMatchDataPosition pos;
         pos.setElementWeight(index_weight);
-        rankProgram->match_data().resolveTermField(fooHandles[i])->reset(docId);
-        rankProgram->match_data().resolveTermField(fooHandles[i])->appendPosition(pos);
+        match_data->resolveTermField(fooHandles[i])->reset(docId);
+        match_data->resolveTermField(fooHandles[i])->appendPosition(pos);
     }
     void setBarWeight(uint32_t i, uint32_t docId, int32_t index_weight) {
         ASSERT_LESS(i, barHandles.size());
         TermFieldMatchDataPosition pos;
         pos.setElementWeight(index_weight);
-        rankProgram->match_data().resolveTermField(barHandles[i])->reset(docId);
-        rankProgram->match_data().resolveTermField(barHandles[i])->appendPosition(pos);
+        match_data->resolveTermField(barHandles[i])->reset(docId);
+        match_data->resolveTermField(barHandles[i])->appendPosition(pos);
     }
 };
 
diff --git a/searchlib/src/tests/features/raw_score/raw_score_test.cpp b/searchlib/src/tests/features/raw_score/raw_score_test.cpp
index 52587c0d8f9..4aad6c6896e 100644
--- a/searchlib/src/tests/features/raw_score/raw_score_test.cpp
+++ b/searchlib/src/tests/features/raw_score/raw_score_test.cpp
@@ -45,13 +45,14 @@ struct FeatureDumpFixture : public IDumpFeatureVisitor {
 struct RankFixture : BlueprintFactoryFixture, IndexFixture {
     QueryEnvironment         queryEnv;
     RankSetup                rankSetup;
-    RankProgram::UP          rankProgram;
     MatchDataLayout          mdl;
+    MatchData::UP            match_data;
+    RankProgram::UP          rankProgram;
     std::vector<TermFieldHandle> fooHandles;
     std::vector<TermFieldHandle> barHandles;
     RankFixture(size_t fooCnt, size_t barCnt)
         : queryEnv(&indexEnv), rankSetup(factory, indexEnv),
-          rankProgram(), mdl(), fooHandles(), barHandles()
+          mdl(), match_data(), rankProgram(), fooHandles(), barHandles()
     {
         for (size_t i = 0; i < fooCnt; ++i) {
             uint32_t fieldId = indexEnv.getFieldByName("foo")->id();
@@ -70,14 +71,15 @@ struct RankFixture : BlueprintFactoryFixture, IndexFixture {
         rankSetup.setFirstPhaseRank(featureName);
         rankSetup.setIgnoreDefaultRankFeatures(true);
         ASSERT_TRUE(rankSetup.compile());
+        match_data = mdl.createMatchData();
         rankProgram = rankSetup.create_first_phase_program();
-        rankProgram->setup(mdl, queryEnv);
+        rankProgram->setup(*match_data, queryEnv);
     }
     feature_t getScore(uint32_t docId) {
         return Utils::getScoreFeature(*rankProgram, docId);
     }
     void setScore(TermFieldHandle handle, uint32_t docId, feature_t score) {
-        rankProgram->match_data().resolveTermField(handle)->setRawScore(docId, score);
+        match_data->resolveTermField(handle)->setRawScore(docId, score);
     }
     void setFooScore(uint32_t i, uint32_t docId, feature_t score) {
         ASSERT_LESS(i, fooHandles.size());
diff --git a/searchlib/src/tests/features/subqueries/subqueries_test.cpp b/searchlib/src/tests/features/subqueries/subqueries_test.cpp
index 37e43b4d2b0..d275cf134c6 100644
--- a/searchlib/src/tests/features/subqueries/subqueries_test.cpp
+++ b/searchlib/src/tests/features/subqueries/subqueries_test.cpp
@@ -43,22 +43,24 @@ struct FeatureDumpFixture : public IDumpFeatureVisitor {
 struct RankFixture : BlueprintFactoryFixture, IndexFixture {
     QueryEnvironment         queryEnv;
     RankSetup                rankSetup;
-    RankProgram::UP          rankProgram;
     MatchDataLayout          mdl;
+    MatchData::UP            match_data;
+    RankProgram::UP          rankProgram;
     std::vector<TermFieldHandle> fooHandles;
     std::vector<TermFieldHandle> barHandles;
     RankFixture(size_t fooCnt, size_t barCnt,
                 std::string featureName = "subqueries(foo)")
         : queryEnv(&indexEnv), rankSetup(factory, indexEnv),
-          rankProgram(), mdl(), fooHandles(), barHandles()
+          mdl(), match_data(), rankProgram(), fooHandles(), barHandles()
     {
         fooHandles = addFields(fooCnt, indexEnv.getFieldByName("foo")->id());
         barHandles = addFields(barCnt, indexEnv.getFieldByName("bar")->id());
         rankSetup.setFirstPhaseRank(featureName);
         rankSetup.setIgnoreDefaultRankFeatures(true);
         ASSERT_TRUE(rankSetup.compile());
+        match_data = mdl.createMatchData();
         rankProgram = rankSetup.create_first_phase_program();
-        rankProgram->setup(mdl, queryEnv);
+        rankProgram->setup(*match_data, queryEnv);
     }
     std::vector<TermFieldHandle> addFields(size_t count, uint32_t fieldId) {
         std::vector<TermFieldHandle> handles;
@@ -75,7 +77,7 @@ struct RankFixture : BlueprintFactoryFixture, IndexFixture {
     }
     void setSubqueries(TermFieldHandle handle, uint32_t docId,
                        uint64_t subqueries) {
-        rankProgram->match_data().resolveTermField(handle)->setSubqueries(docId, subqueries);
+        match_data->resolveTermField(handle)->setSubqueries(docId, subqueries);
     }
     void setFooSubqueries(uint32_t i, uint32_t docId, uint64_t subqueries) {
         ASSERT_LESS(i, fooHandles.size());
diff --git a/searchlib/src/tests/fef/featureoverride/featureoverride.cpp b/searchlib/src/tests/fef/featureoverride/featureoverride.cpp
index 0ff7e0899e9..e55bd7081a1 100644
--- a/searchlib/src/tests/fef/featureoverride/featureoverride.cpp
+++ b/searchlib/src/tests/fef/featureoverride/featureoverride.cpp
@@ -141,7 +141,8 @@ TEST("test overrides")
     overrides.add("value(1,2,3).2",  "6.0");
     overrides.add("bogus(feature)", "10.0");
 
-    rankProgram->setup(mdl, queryEnv, overrides);
+    MatchData::UP match_data = mdl.createMatchData();
+    rankProgram->setup(*match_data, queryEnv, overrides);
 
     std::map<vespalib::string, feature_t> res = Utils::getAllFeatures(*rankProgram, 2);
 
diff --git a/searchlib/src/tests/fef/object_passing/object_passing_test.cpp b/searchlib/src/tests/fef/object_passing/object_passing_test.cpp
index 5c0f09a1203..3ae5932889a 100644
--- a/searchlib/src/tests/fef/object_passing/object_passing_test.cpp
+++ b/searchlib/src/tests/fef/object_passing/object_passing_test.cpp
@@ -7,6 +7,7 @@
 #include <vespa/searchlib/fef/test/indexenvironment.h>
 #include <vespa/searchlib/fef/test/queryenvironment.h>
 #include <vespa/searchlib/fef/test/plugin/unbox.h>
+#include <vespa/searchlib/fef/matchdatalayout.h>
 #include <vespa/searchlib/fef/rank_program.h>
 #include <vespa/searchlib/fef/verify_feature.h>
 #include <vespa/eval/eval/value_type.h>
@@ -87,10 +88,11 @@ struct Fixture {
             return vespalib::eval::error_value;        
         }
         MatchDataLayout mdl;
+        MatchData::UP md = mdl.createMatchData();
         QueryEnvironment queryEnv(&indexEnv);
         Properties overrides;
         RankProgram program(resolver);
-        program.setup(mdl, queryEnv, overrides);        
+        program.setup(*md, queryEnv, overrides);        
         auto result = program.get_seeds();
         EXPECT_EQUAL(1u, result.num_features());
         EXPECT_TRUE(!result.is_object(0)); // verifies auto-unboxing
diff --git a/searchlib/src/tests/fef/rank_program/rank_program_test.cpp b/searchlib/src/tests/fef/rank_program/rank_program_test.cpp
index 8e23731e961..7e28178e5f7 100644
--- a/searchlib/src/tests/fef/rank_program/rank_program_test.cpp
+++ b/searchlib/src/tests/fef/rank_program/rank_program_test.cpp
@@ -6,6 +6,7 @@
 #include <vespa/searchlib/features/rankingexpressionfeature.h>
 #include <vespa/searchlib/fef/blueprintfactory.h>
 #include <vespa/searchlib/fef/indexproperties.h>
+#include <vespa/searchlib/fef/matchdatalayout.h>
 #include <vespa/searchlib/fef/test/indexenvironment.h>
 #include <vespa/searchlib/fef/test/queryenvironment.h>
 #include <vespa/searchlib/fef/test/plugin/sum.h>
@@ -69,10 +70,11 @@ struct Fixture {
     IndexEnvironment indexEnv;
     BlueprintResolver::SP resolver;
     Properties overrides;
+    MatchData::UP match_data;
     RankProgram program;
     size_t track_cnt;
     Fixture() : factory(), indexEnv(), resolver(new BlueprintResolver(factory, indexEnv)),
-                overrides(), program(resolver), track_cnt(0)
+                overrides(), match_data(), program(resolver), track_cnt(0)
     {
         factory.addPrototype(Blueprint::SP(new BoxingBlueprint()));
         factory.addPrototype(Blueprint::SP(new DocidBlueprint()));
@@ -107,7 +109,8 @@ struct Fixture {
         ASSERT_TRUE(resolver->compile());
         MatchDataLayout mdl;
         QueryEnvironment queryEnv(&indexEnv);
-        program.setup(mdl, queryEnv, overrides);
+        match_data = mdl.createMatchData();
+        program.setup(*match_data, queryEnv, overrides);
         return *this;
     }
     double get(uint32_t docid = default_docid) {
diff --git a/searchlib/src/tests/fef/termfieldmodel/termfieldmodel_test.cpp b/searchlib/src/tests/fef/termfieldmodel/termfieldmodel_test.cpp
index 57fb19b7b23..01c72497246 100644
--- a/searchlib/src/tests/fef/termfieldmodel/termfieldmodel_test.cpp
+++ b/searchlib/src/tests/fef/termfieldmodel/termfieldmodel_test.cpp
@@ -207,4 +207,39 @@ TEST("Access subqueries") {
     EXPECT_EQUAL(0ULL, state.f3->getSubqueries());
 }
 
+TEST("require that TermFieldMatchData can be tagged as needed or not") {
+    TermFieldMatchData tfmd;
+    tfmd.setFieldId(123);
+    EXPECT_EQUAL(tfmd.getFieldId(),123u);
+    EXPECT_TRUE(!tfmd.isNotNeeded());
+    tfmd.tagAsNotNeeded();
+    EXPECT_EQUAL(tfmd.getFieldId(),123u);
+    EXPECT_TRUE(tfmd.isNotNeeded());
+    tfmd.tagAsNeeded();
+    EXPECT_EQUAL(tfmd.getFieldId(),123u);
+    EXPECT_TRUE(!tfmd.isNotNeeded());
+}
+
+TEST("require that MatchData soft_reset retains appropriate state") {    
+    auto md = MatchData::makeTestInstance(10, 10);
+    md->set_termwise_limit(0.5);
+    auto *old_term = md->resolveTermField(7); 
+    old_term->tagAsNotNeeded();
+    old_term->populate_fixed()->setElementWeight(21);
+    old_term->resetOnlyDocId(42);
+    EXPECT_EQUAL(md->get_termwise_limit(), 0.5);
+    EXPECT_TRUE(old_term->isNotNeeded());
+    EXPECT_EQUAL(old_term->getFieldId(), 7u);
+    EXPECT_EQUAL(old_term->getWeight(), 21);
+    EXPECT_EQUAL(old_term->getDocId(), 42u);
+    md->soft_reset();
+    auto *new_term = md->resolveTermField(7);
+    EXPECT_EQUAL(new_term, old_term);
+    EXPECT_EQUAL(md->get_termwise_limit(), 1.0);
+    EXPECT_TRUE(!new_term->isNotNeeded());
+    EXPECT_EQUAL(new_term->getFieldId(), 7u);
+    EXPECT_EQUAL(new_term->getWeight(), 21);
+    EXPECT_EQUAL(new_term->getDocId(), TermFieldMatchData::invalidId());
+}
+
 TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/searchlib/src/tests/ranksetup/ranksetup_test.cpp b/searchlib/src/tests/ranksetup/ranksetup_test.cpp
index c2ef8f3a46b..7a26180eed2 100644
--- a/searchlib/src/tests/ranksetup/ranksetup_test.cpp
+++ b/searchlib/src/tests/ranksetup/ranksetup_test.cpp
@@ -87,6 +87,7 @@ private:
     const RankEnvironment & _rankEnv;
     MatchDataLayout _layout;
     std::unique_ptr<RankSetup> _rs;
+    MatchData::UP _match_data;
     RankProgram::UP _firstPhaseProgram;
     RankProgram::UP _secondPhaseProgram;
 
@@ -100,7 +101,7 @@ public:
 RankExecutor::RankExecutor(const vespalib::string &initRank, const vespalib::string &finalRank,
                            const RankEnvironment &rankEnv)
     : _initRank(initRank), _finalRank(finalRank), _rankEnv(rankEnv), _layout(),
-      _rs(), _firstPhaseProgram(), _secondPhaseProgram()
+      _rs(), _match_data(), _firstPhaseProgram(), _secondPhaseProgram()
 {}
 
 RankExecutor::~RankExecutor() {}
@@ -121,12 +122,13 @@ RankExecutor::setup()
     if (!_rs->compile()) {
         return false;
     }
+    _match_data = _layout.createMatchData();
 
     _firstPhaseProgram = _rs->create_first_phase_program();
-    _firstPhaseProgram->setup(_layout, _rankEnv.queryEnvironment());
+    _firstPhaseProgram->setup(*_match_data, _rankEnv.queryEnvironment());
     if (!_finalRank.empty()) {
         _secondPhaseProgram = _rs->create_second_phase_program();
-        _secondPhaseProgram->setup(_layout, _rankEnv.queryEnvironment());
+        _secondPhaseProgram->setup(*_match_data, _rankEnv.queryEnvironment());
     }
     return true;
 }
@@ -154,6 +156,7 @@ private:
     const RankEnvironment & _rankEnv;
     RankSetup _setup;
     MatchDataLayout _layout;
+    MatchData::UP _match_data;
     RankProgram::UP _rankProgram;
 
 public:
@@ -169,6 +172,7 @@ FeatureDumper::FeatureDumper(const RankEnvironment & rankEnv)
     : _rankEnv(rankEnv),
       _setup(_rankEnv.factory(), _rankEnv.indexEnvironment()),
       _layout(),
+      _match_data(),
       _rankProgram()
 {}
 FeatureDumper::~FeatureDumper() {}
@@ -191,8 +195,9 @@ FeatureDumper::setup()
         return false;
     }
 
+    _match_data = _layout.createMatchData();
     _rankProgram = _setup.create_dump_program();
-    _rankProgram->setup(_layout, _rankEnv.queryEnvironment());
+    _rankProgram->setup(*_match_data, _rankEnv.queryEnvironment());
     return true;
 }
 
@@ -780,12 +785,13 @@ RankSetupTest::testFeatureNormalization()
     { // RANK context
         MatchDataLayout layout;
         QueryEnvironment queryEnv;
+        MatchData::UP match_data = layout.createMatchData();
         RankProgram::UP firstPhaseProgram = rankSetup.create_first_phase_program();
         RankProgram::UP secondPhaseProgram = rankSetup.create_second_phase_program();
         RankProgram::UP summaryProgram = rankSetup.create_summary_program();
-        firstPhaseProgram->setup(layout, queryEnv);
-        secondPhaseProgram->setup(layout, queryEnv);
-        summaryProgram->setup(layout, queryEnv);
+        firstPhaseProgram->setup(*match_data, queryEnv);
+        secondPhaseProgram->setup(*match_data, queryEnv);
+        summaryProgram->setup(*match_data, queryEnv);
 
         EXPECT_APPROX(2.0, Utils::getScoreFeature(*firstPhaseProgram, 1), 0.001);
         EXPECT_APPROX(4.0, Utils::getScoreFeature(*secondPhaseProgram, 1), 0.001);
@@ -831,8 +837,9 @@ RankSetupTest::testFeatureNormalization()
     { // DUMP context
         MatchDataLayout layout;
         QueryEnvironment queryEnv;
+        MatchData::UP match_data = layout.createMatchData();
         RankProgram::UP rankProgram = rankSetup.create_dump_program();
-        rankProgram->setup(layout, queryEnv);
+        rankProgram->setup(*match_data, queryEnv);
 
         { // dump seed features
             std::map<vespalib::string, feature_t> actual = Utils::getSeedFeatures(*rankProgram, 1);
diff --git a/searchlib/src/vespa/searchlib/features/attributematchfeature.cpp b/searchlib/src/vespa/searchlib/features/attributematchfeature.cpp
index bf3297f3e14..2ff53951d8b 100644
--- a/searchlib/src/vespa/searchlib/features/attributematchfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/attributematchfeature.cpp
@@ -253,7 +253,7 @@ AttributeMatchExecutor<T>::execute(uint32_t docId)
 
 template <typename T>
 void
-AttributeMatchExecutor<T>::handle_bind_match_data(MatchData &md)
+AttributeMatchExecutor<T>::handle_bind_match_data(const MatchData &md)
 {
     _cmp.bind_match_data(md);
 }
diff --git a/searchlib/src/vespa/searchlib/features/attributematchfeature.h b/searchlib/src/vespa/searchlib/features/attributematchfeature.h
index 8396493b81d..707572abf9e 100644
--- a/searchlib/src/vespa/searchlib/features/attributematchfeature.h
+++ b/searchlib/src/vespa/searchlib/features/attributematchfeature.h
@@ -69,12 +69,12 @@ private:
         feature_t getWeight() const;
         feature_t getSignificance() const;
         feature_t getImportance() const { return (getWeight() + getSignificance()) * 0.5; }
-        void bind_match_data(fef::MatchData &md) { _md = &md; }
+        void bind_match_data(const fef::MatchData &md) { _md = &md; }
     };
 
     Computer _cmp;
 
-    virtual void handle_bind_match_data(fef::MatchData &md) override;
+    virtual void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     /**
diff --git a/searchlib/src/vespa/searchlib/features/element_completeness_feature.cpp b/searchlib/src/vespa/searchlib/features/element_completeness_feature.cpp
index c3bb87379ad..18988281cbd 100644
--- a/searchlib/src/vespa/searchlib/features/element_completeness_feature.cpp
+++ b/searchlib/src/vespa/searchlib/features/element_completeness_feature.cpp
@@ -73,7 +73,7 @@ ElementCompletenessExecutor::execute(uint32_t docId)
 }
 
 void
-ElementCompletenessExecutor::handle_bind_match_data(fef::MatchData &md)
+ElementCompletenessExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/element_completeness_feature.h b/searchlib/src/vespa/searchlib/features/element_completeness_feature.h
index 013efaedc22..1b835da45d2 100644
--- a/searchlib/src/vespa/searchlib/features/element_completeness_feature.h
+++ b/searchlib/src/vespa/searchlib/features/element_completeness_feature.h
@@ -82,7 +82,7 @@ private:
 
     static bool nextElement(Item &item);
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     ElementCompletenessExecutor(const fef::IQueryEnvironment &env,
diff --git a/searchlib/src/vespa/searchlib/features/element_similarity_feature.cpp b/searchlib/src/vespa/searchlib/features/element_similarity_feature.cpp
index e3c0217be15..c9eab238f82 100644
--- a/searchlib/src/vespa/searchlib/features/element_similarity_feature.cpp
+++ b/searchlib/src/vespa/searchlib/features/element_similarity_feature.cpp
@@ -230,7 +230,7 @@ public:
 
     bool isPure() override { return _terms.handles.empty(); }
 
-    void handle_bind_match_data(fef::MatchData &md) override {
+    void handle_bind_match_data(const fef::MatchData &md) override {
         _md = &md;
     }
 
diff --git a/searchlib/src/vespa/searchlib/features/fieldinfofeature.cpp b/searchlib/src/vespa/searchlib/features/fieldinfofeature.cpp
index 85f3fc9b652..960dcc7dfd1 100644
--- a/searchlib/src/vespa/searchlib/features/fieldinfofeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/fieldinfofeature.cpp
@@ -59,7 +59,7 @@ IndexFieldInfoExecutor::execute(uint32_t docId)
 }
 
 void
-IndexFieldInfoExecutor::handle_bind_match_data(fef::MatchData &md)
+IndexFieldInfoExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
@@ -98,7 +98,7 @@ AttrFieldInfoExecutor::execute(uint32_t docId)
 }
 
 void
-AttrFieldInfoExecutor::handle_bind_match_data(fef::MatchData &md)
+AttrFieldInfoExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/fieldinfofeature.h b/searchlib/src/vespa/searchlib/features/fieldinfofeature.h
index 08cf99ed32a..7ced5d5cb9f 100644
--- a/searchlib/src/vespa/searchlib/features/fieldinfofeature.h
+++ b/searchlib/src/vespa/searchlib/features/fieldinfofeature.h
@@ -18,7 +18,7 @@ private:
     uint32_t  _fieldHandle;
     const fef::MatchData *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     IndexFieldInfoExecutor(feature_t type, feature_t isFilter,
@@ -35,7 +35,7 @@ private:
     uint32_t  _fieldHandle;
     const fef::MatchData *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     AttrFieldInfoExecutor(feature_t type, uint32_t fieldHandle);
diff --git a/searchlib/src/vespa/searchlib/features/fieldlengthfeature.cpp b/searchlib/src/vespa/searchlib/features/fieldlengthfeature.cpp
index 0ec1f8bd038..d0680e8fc19 100644
--- a/searchlib/src/vespa/searchlib/features/fieldlengthfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/fieldlengthfeature.cpp
@@ -56,7 +56,7 @@ FieldLengthExecutor::execute(uint32_t docId)
 }
 
 void
-FieldLengthExecutor::handle_bind_match_data(MatchData &md)
+FieldLengthExecutor::handle_bind_match_data(const MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/fieldlengthfeature.h b/searchlib/src/vespa/searchlib/features/fieldlengthfeature.h
index a818a65d26e..4988bb97546 100644
--- a/searchlib/src/vespa/searchlib/features/fieldlengthfeature.h
+++ b/searchlib/src/vespa/searchlib/features/fieldlengthfeature.h
@@ -15,7 +15,7 @@ private:
     std::vector<fef::TermFieldHandle> _fieldHandles;
     const fef::MatchData             *_md;
 
-    virtual void handle_bind_match_data(fef::MatchData &md) override;
+    virtual void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     /**
diff --git a/searchlib/src/vespa/searchlib/features/fieldmatchfeature.cpp b/searchlib/src/vespa/searchlib/features/fieldmatchfeature.cpp
index bea6e032e81..f5f8652461e 100644
--- a/searchlib/src/vespa/searchlib/features/fieldmatchfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/fieldmatchfeature.cpp
@@ -86,7 +86,7 @@ FieldMatchExecutor::execute(uint32_t docId)
 }
 
 void
-FieldMatchExecutor::handle_bind_match_data(fef::MatchData &md)
+FieldMatchExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _splitter.bind_match_data(md);
 }
diff --git a/searchlib/src/vespa/searchlib/features/fieldmatchfeature.h b/searchlib/src/vespa/searchlib/features/fieldmatchfeature.h
index 287af60b021..71ac1023df6 100644
--- a/searchlib/src/vespa/searchlib/features/fieldmatchfeature.h
+++ b/searchlib/src/vespa/searchlib/features/fieldmatchfeature.h
@@ -19,7 +19,7 @@ private:
     const fieldmatch::Params              & _params;
     fieldmatch::Computer                    _cmp;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     /**
diff --git a/searchlib/src/vespa/searchlib/features/fieldtermmatchfeature.cpp b/searchlib/src/vespa/searchlib/features/fieldtermmatchfeature.cpp
index 0f71d5dcbec..a7a00bee956 100644
--- a/searchlib/src/vespa/searchlib/features/fieldtermmatchfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/fieldtermmatchfeature.cpp
@@ -63,7 +63,7 @@ FieldTermMatchExecutor::execute(uint32_t docId)
 }
 
 void
-FieldTermMatchExecutor::handle_bind_match_data(fef::MatchData &md)
+FieldTermMatchExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/fieldtermmatchfeature.h b/searchlib/src/vespa/searchlib/features/fieldtermmatchfeature.h
index 02dfa17ba33..0f89f7eeb75 100644
--- a/searchlib/src/vespa/searchlib/features/fieldtermmatchfeature.h
+++ b/searchlib/src/vespa/searchlib/features/fieldtermmatchfeature.h
@@ -27,7 +27,7 @@ private:
     fef::TermFieldHandle _fieldHandle;
     const fef::MatchData        *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 };
 
 /**
diff --git a/searchlib/src/vespa/searchlib/features/flow_completeness_feature.cpp b/searchlib/src/vespa/searchlib/features/flow_completeness_feature.cpp
index 5c93566698e..c46d602983d 100644
--- a/searchlib/src/vespa/searchlib/features/flow_completeness_feature.cpp
+++ b/searchlib/src/vespa/searchlib/features/flow_completeness_feature.cpp
@@ -234,7 +234,7 @@ FlowCompletenessExecutor::execute(uint32_t)
 }
 
 void
-FlowCompletenessExecutor::handle_bind_match_data(fef::MatchData &md)
+FlowCompletenessExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/flow_completeness_feature.h b/searchlib/src/vespa/searchlib/features/flow_completeness_feature.h
index cdfa0356307..db5c53beac8 100644
--- a/searchlib/src/vespa/searchlib/features/flow_completeness_feature.h
+++ b/searchlib/src/vespa/searchlib/features/flow_completeness_feature.h
@@ -62,7 +62,7 @@ private:
 
     static bool nextElement(Item &item);
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     FlowCompletenessExecutor(const fef::IQueryEnvironment &env,
diff --git a/searchlib/src/vespa/searchlib/features/item_raw_score_feature.cpp b/searchlib/src/vespa/searchlib/features/item_raw_score_feature.cpp
index a7476185000..45baf646656 100644
--- a/searchlib/src/vespa/searchlib/features/item_raw_score_feature.cpp
+++ b/searchlib/src/vespa/searchlib/features/item_raw_score_feature.cpp
@@ -23,7 +23,7 @@ ItemRawScoreExecutor::execute(uint32_t docId)
 }
 
 void
-ItemRawScoreExecutor::handle_bind_match_data(MatchData &md)
+ItemRawScoreExecutor::handle_bind_match_data(const MatchData &md)
 {
     _md = &md;
 }
@@ -42,7 +42,7 @@ SimpleItemRawScoreExecutor::execute(uint32_t docId)
 }
 
 void
-SimpleItemRawScoreExecutor::handle_bind_match_data(MatchData &md)
+SimpleItemRawScoreExecutor::handle_bind_match_data(const MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/item_raw_score_feature.h b/searchlib/src/vespa/searchlib/features/item_raw_score_feature.h
index 3aa1672b05d..d6a55f29632 100644
--- a/searchlib/src/vespa/searchlib/features/item_raw_score_feature.h
+++ b/searchlib/src/vespa/searchlib/features/item_raw_score_feature.h
@@ -16,7 +16,7 @@ private:
     HandleVector _handles;
     const fef::MatchData *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     ItemRawScoreExecutor(HandleVector handles)
@@ -30,7 +30,7 @@ private:
     fef::TermFieldHandle _handle;
     const fef::MatchData *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     SimpleItemRawScoreExecutor(fef::TermFieldHandle handle)
diff --git a/searchlib/src/vespa/searchlib/features/jarowinklerdistancefeature.cpp b/searchlib/src/vespa/searchlib/features/jarowinklerdistancefeature.cpp
index 3f4817d61d2..a5e3e2da5ba 100644
--- a/searchlib/src/vespa/searchlib/features/jarowinklerdistancefeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/jarowinklerdistancefeature.cpp
@@ -59,7 +59,7 @@ JaroWinklerDistanceExecutor::execute(uint32_t docId)
 }
 
 void
-JaroWinklerDistanceExecutor::handle_bind_match_data(fef::MatchData &md)
+JaroWinklerDistanceExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/jarowinklerdistancefeature.h b/searchlib/src/vespa/searchlib/features/jarowinklerdistancefeature.h
index 0497d2a2f73..a8d6eacf0eb 100644
--- a/searchlib/src/vespa/searchlib/features/jarowinklerdistancefeature.h
+++ b/searchlib/src/vespa/searchlib/features/jarowinklerdistancefeature.h
@@ -43,7 +43,7 @@ private:
     std::vector<fef::TermFieldHandle> _termFieldHandles; // The handles of all query terms.
     const fef::MatchData             *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 };
 
 /**
diff --git a/searchlib/src/vespa/searchlib/features/matchcountfeature.cpp b/searchlib/src/vespa/searchlib/features/matchcountfeature.cpp
index 51a7a952781..fd453e17eb1 100644
--- a/searchlib/src/vespa/searchlib/features/matchcountfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/matchcountfeature.cpp
@@ -36,7 +36,7 @@ MatchCountExecutor::execute(uint32_t docId)
 }
 
 void
-MatchCountExecutor::handle_bind_match_data(MatchData &md)
+MatchCountExecutor::handle_bind_match_data(const MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/matchcountfeature.h b/searchlib/src/vespa/searchlib/features/matchcountfeature.h
index c4123016e16..eadb5064c57 100644
--- a/searchlib/src/vespa/searchlib/features/matchcountfeature.h
+++ b/searchlib/src/vespa/searchlib/features/matchcountfeature.h
@@ -18,7 +18,7 @@ private:
     std::vector<fef::TermFieldHandle> _handles;
     const fef::MatchData             *_md;
 
-    virtual void handle_bind_match_data(fef::MatchData &md) override;
+    virtual void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     MatchCountExecutor(uint32_t fieldId, const fef::IQueryEnvironment &env);
diff --git a/searchlib/src/vespa/searchlib/features/matchesfeature.cpp b/searchlib/src/vespa/searchlib/features/matchesfeature.cpp
index c2e36551648..f4788ee74c8 100644
--- a/searchlib/src/vespa/searchlib/features/matchesfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/matchesfeature.cpp
@@ -40,7 +40,7 @@ MatchesExecutor::execute(uint32_t docId)
 }
 
 void
-MatchesExecutor::handle_bind_match_data(MatchData &md)
+MatchesExecutor::handle_bind_match_data(const MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/matchesfeature.h b/searchlib/src/vespa/searchlib/features/matchesfeature.h
index fe82929d2a7..c6366349dd9 100644
--- a/searchlib/src/vespa/searchlib/features/matchesfeature.h
+++ b/searchlib/src/vespa/searchlib/features/matchesfeature.h
@@ -18,7 +18,7 @@ private:
     std::vector<fef::TermFieldHandle> _handles;
     const fef::MatchData             *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     MatchesExecutor(uint32_t fieldId,
diff --git a/searchlib/src/vespa/searchlib/features/native_dot_product_feature.cpp b/searchlib/src/vespa/searchlib/features/native_dot_product_feature.cpp
index 6986703eaf6..cb8136e8b7f 100644
--- a/searchlib/src/vespa/searchlib/features/native_dot_product_feature.cpp
+++ b/searchlib/src/vespa/searchlib/features/native_dot_product_feature.cpp
@@ -35,7 +35,7 @@ NativeDotProductExecutor::execute(uint32_t docId)
 }
 
 void
-NativeDotProductExecutor::handle_bind_match_data(fef::MatchData &md)
+NativeDotProductExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/native_dot_product_feature.h b/searchlib/src/vespa/searchlib/features/native_dot_product_feature.h
index cc29ecd5e6b..a71d23f3158 100644
--- a/searchlib/src/vespa/searchlib/features/native_dot_product_feature.h
+++ b/searchlib/src/vespa/searchlib/features/native_dot_product_feature.h
@@ -17,7 +17,7 @@ private:
     std::vector<Pair>     _pairs;
     const fef::MatchData *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     NativeDotProductExecutor(const fef::IQueryEnvironment &env, uint32_t fieldId);
diff --git a/searchlib/src/vespa/searchlib/features/nativeattributematchfeature.cpp b/searchlib/src/vespa/searchlib/features/nativeattributematchfeature.cpp
index 4243bb83e03..1e6423f9de8 100644
--- a/searchlib/src/vespa/searchlib/features/nativeattributematchfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/nativeattributematchfeature.cpp
@@ -73,7 +73,7 @@ NativeAttributeMatchExecutorMulti::execute(uint32_t docId)
 }
 
 void
-NativeAttributeMatchExecutorMulti::handle_bind_match_data(MatchData &md)
+NativeAttributeMatchExecutorMulti::handle_bind_match_data(const MatchData &md)
 {
     _md = &md;
 }
@@ -88,7 +88,7 @@ NativeAttributeMatchExecutorSingle::execute(uint32_t docId)
 }
 
 void
-NativeAttributeMatchExecutorSingle::handle_bind_match_data(MatchData &md)
+NativeAttributeMatchExecutorSingle::handle_bind_match_data(const MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/nativeattributematchfeature.h b/searchlib/src/vespa/searchlib/features/nativeattributematchfeature.h
index 4ebdc871bb5..e47cbed0344 100644
--- a/searchlib/src/vespa/searchlib/features/nativeattributematchfeature.h
+++ b/searchlib/src/vespa/searchlib/features/nativeattributematchfeature.h
@@ -57,7 +57,7 @@ private:
     std::vector<CachedTermData>        _queryTermData;
     const fef::MatchData              *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 public:
     NativeAttributeMatchExecutorMulti(const Precomputed & setup) : _divisor(setup.second), _queryTermData(setup.first), _md(nullptr) { }
     void execute(uint32_t docId) override;
@@ -69,7 +69,7 @@ private:
     CachedTermData _queryTermData;
     const fef::MatchData *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     NativeAttributeMatchExecutorSingle(const Precomputed & setup) :
diff --git a/searchlib/src/vespa/searchlib/features/nativefieldmatchfeature.cpp b/searchlib/src/vespa/searchlib/features/nativefieldmatchfeature.cpp
index e4b633d54dd..84ad17e1cb0 100644
--- a/searchlib/src/vespa/searchlib/features/nativefieldmatchfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/nativefieldmatchfeature.cpp
@@ -83,7 +83,7 @@ NativeFieldMatchExecutor::execute(uint32_t docId)
 }
 
 void
-NativeFieldMatchExecutor::handle_bind_match_data(fef::MatchData &md)
+NativeFieldMatchExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/nativefieldmatchfeature.h b/searchlib/src/vespa/searchlib/features/nativefieldmatchfeature.h
index d47dece1654..cb676e5b775 100644
--- a/searchlib/src/vespa/searchlib/features/nativefieldmatchfeature.h
+++ b/searchlib/src/vespa/searchlib/features/nativefieldmatchfeature.h
@@ -73,7 +73,7 @@ private:
         return table->get(index);
     }
 
-    virtual void handle_bind_match_data(fef::MatchData &md) override;
+    virtual void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     NativeFieldMatchExecutor(const fef::IQueryEnvironment & env,
diff --git a/searchlib/src/vespa/searchlib/features/nativeproximityfeature.cpp b/searchlib/src/vespa/searchlib/features/nativeproximityfeature.cpp
index 3c92db6b937..a31d9207e05 100644
--- a/searchlib/src/vespa/searchlib/features/nativeproximityfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/nativeproximityfeature.cpp
@@ -97,7 +97,7 @@ NativeProximityExecutor::execute(uint32_t docId)
 }
 
 void
-NativeProximityExecutor::handle_bind_match_data(fef::MatchData &md)
+NativeProximityExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/nativeproximityfeature.h b/searchlib/src/vespa/searchlib/features/nativeproximityfeature.h
index cda6776d42e..f98fe2bfd22 100644
--- a/searchlib/src/vespa/searchlib/features/nativeproximityfeature.h
+++ b/searchlib/src/vespa/searchlib/features/nativeproximityfeature.h
@@ -62,7 +62,7 @@ private:
     feature_t calculateScoreForField(const FieldSetup & fs, uint32_t docId);
     feature_t calculateScoreForPair(const TermPair & pair, uint32_t fieldId, uint32_t docId);
 
-    virtual void handle_bind_match_data(fef::MatchData &md) override;
+    virtual void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     NativeProximityExecutor(const fef::IQueryEnvironment & env, const NativeProximityParams & params);
diff --git a/searchlib/src/vespa/searchlib/features/proximityfeature.cpp b/searchlib/src/vespa/searchlib/features/proximityfeature.cpp
index e6303ace100..f625e30f378 100644
--- a/searchlib/src/vespa/searchlib/features/proximityfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/proximityfeature.cpp
@@ -51,7 +51,7 @@ ProximityExecutor::execute(uint32_t docId)
 }
 
 void
-ProximityExecutor::handle_bind_match_data(fef::MatchData &md)
+ProximityExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/proximityfeature.h b/searchlib/src/vespa/searchlib/features/proximityfeature.h
index 5a46bafe869..14a80628004 100644
--- a/searchlib/src/vespa/searchlib/features/proximityfeature.h
+++ b/searchlib/src/vespa/searchlib/features/proximityfeature.h
@@ -41,7 +41,7 @@ private:
 
     bool findBest(const fef::TermFieldMatchData &matchA,
                   const fef::TermFieldMatchData &matchB);
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 };
 
 /**
diff --git a/searchlib/src/vespa/searchlib/features/querycompletenessfeature.cpp b/searchlib/src/vespa/searchlib/features/querycompletenessfeature.cpp
index af44f75e33f..b4b6a1b0eb4 100644
--- a/searchlib/src/vespa/searchlib/features/querycompletenessfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/querycompletenessfeature.cpp
@@ -62,7 +62,7 @@ QueryCompletenessExecutor::execute(uint32_t docId)
 }
 
 void
-QueryCompletenessExecutor::handle_bind_match_data(fef::MatchData &md)
+QueryCompletenessExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/querycompletenessfeature.h b/searchlib/src/vespa/searchlib/features/querycompletenessfeature.h
index 5e30563f6ec..a5e6bbdc2bb 100644
--- a/searchlib/src/vespa/searchlib/features/querycompletenessfeature.h
+++ b/searchlib/src/vespa/searchlib/features/querycompletenessfeature.h
@@ -38,7 +38,7 @@ private:
     std::vector<fef::TermFieldHandle> _fieldHandles;
     const fef::MatchData                     *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 };
 
 /**
diff --git a/searchlib/src/vespa/searchlib/features/raw_score_feature.cpp b/searchlib/src/vespa/searchlib/features/raw_score_feature.cpp
index 2fa59111d00..02e44e781d4 100644
--- a/searchlib/src/vespa/searchlib/features/raw_score_feature.cpp
+++ b/searchlib/src/vespa/searchlib/features/raw_score_feature.cpp
@@ -35,7 +35,7 @@ RawScoreExecutor::execute(uint32_t docId)
 }
 
 void
-RawScoreExecutor::handle_bind_match_data(fef::MatchData &md)
+RawScoreExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/raw_score_feature.h b/searchlib/src/vespa/searchlib/features/raw_score_feature.h
index 8bb310fa18e..0eceba16ffe 100644
--- a/searchlib/src/vespa/searchlib/features/raw_score_feature.h
+++ b/searchlib/src/vespa/searchlib/features/raw_score_feature.h
@@ -14,7 +14,7 @@ private:
     std::vector<fef::TermFieldHandle> _handles;
     const fef::MatchData                     *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 public:
     RawScoreExecutor(const fef::IQueryEnvironment &env, uint32_t fieldId);
     void execute(uint32_t docId) override;
diff --git a/searchlib/src/vespa/searchlib/features/reverseproximityfeature.cpp b/searchlib/src/vespa/searchlib/features/reverseproximityfeature.cpp
index 0f35e1becf8..c27936332d2 100644
--- a/searchlib/src/vespa/searchlib/features/reverseproximityfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/reverseproximityfeature.cpp
@@ -90,7 +90,7 @@ ReverseProximityExecutor::execute(uint32_t docId)
 }
 
 void
-ReverseProximityExecutor::handle_bind_match_data(fef::MatchData &md)
+ReverseProximityExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/reverseproximityfeature.h b/searchlib/src/vespa/searchlib/features/reverseproximityfeature.h
index c16448435f2..776dde39f77 100644
--- a/searchlib/src/vespa/searchlib/features/reverseproximityfeature.h
+++ b/searchlib/src/vespa/searchlib/features/reverseproximityfeature.h
@@ -39,7 +39,7 @@ private:
     fef::TermFieldHandle          _termB;  // Handle to the second query term.
     const fef::MatchData         *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 };
 
 /**
diff --git a/searchlib/src/vespa/searchlib/features/subqueries_feature.cpp b/searchlib/src/vespa/searchlib/features/subqueries_feature.cpp
index 4bbb7af9dfb..6c52b6edb76 100644
--- a/searchlib/src/vespa/searchlib/features/subqueries_feature.cpp
+++ b/searchlib/src/vespa/searchlib/features/subqueries_feature.cpp
@@ -37,7 +37,7 @@ void SubqueriesExecutor::execute(uint32_t docId) {
 }
 
 void
-SubqueriesExecutor::handle_bind_match_data(fef::MatchData &md)
+SubqueriesExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/subqueries_feature.h b/searchlib/src/vespa/searchlib/features/subqueries_feature.h
index 60bec51cb79..136d8d90f94 100644
--- a/searchlib/src/vespa/searchlib/features/subqueries_feature.h
+++ b/searchlib/src/vespa/searchlib/features/subqueries_feature.h
@@ -12,7 +12,7 @@ class SubqueriesExecutor : public fef::FeatureExecutor {
     std::vector<fef::TermFieldHandle> _handles;
     const fef::MatchData             *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 public:
     SubqueriesExecutor(const fef::IQueryEnvironment &env, uint32_t fieldId);
     void execute(uint32_t docId) override;
diff --git a/searchlib/src/vespa/searchlib/features/term_field_md_feature.cpp b/searchlib/src/vespa/searchlib/features/term_field_md_feature.cpp
index 97d267071cf..8b0eecd9cff 100644
--- a/searchlib/src/vespa/searchlib/features/term_field_md_feature.cpp
+++ b/searchlib/src/vespa/searchlib/features/term_field_md_feature.cpp
@@ -65,7 +65,7 @@ TermFieldMdExecutor::execute(uint32_t docId)
 }
 
 void
-TermFieldMdExecutor::handle_bind_match_data(MatchData &md)
+TermFieldMdExecutor::handle_bind_match_data(const MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/term_field_md_feature.h b/searchlib/src/vespa/searchlib/features/term_field_md_feature.h
index f819989fc08..df9ab982dcb 100644
--- a/searchlib/src/vespa/searchlib/features/term_field_md_feature.h
+++ b/searchlib/src/vespa/searchlib/features/term_field_md_feature.h
@@ -21,7 +21,7 @@ class TermFieldMdExecutor : public fef::FeatureExecutor {
     const fef::MatchData *_md;
 
     void execute(uint32_t docId) override;
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 public:
     TermFieldMdExecutor(const fef::IQueryEnvironment &env, uint32_t fieldId);
 };
diff --git a/searchlib/src/vespa/searchlib/features/termdistancefeature.cpp b/searchlib/src/vespa/searchlib/features/termdistancefeature.cpp
index a67c6a0be7c..0408f6d4b75 100644
--- a/searchlib/src/vespa/searchlib/features/termdistancefeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/termdistancefeature.cpp
@@ -42,7 +42,7 @@ TermDistanceExecutor::execute(uint32_t docId)
 }
 
 void
-TermDistanceExecutor::handle_bind_match_data(fef::MatchData &md)
+TermDistanceExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/termdistancefeature.h b/searchlib/src/vespa/searchlib/features/termdistancefeature.h
index 5c4542a1f0d..8e153072bc2 100644
--- a/searchlib/src/vespa/searchlib/features/termdistancefeature.h
+++ b/searchlib/src/vespa/searchlib/features/termdistancefeature.h
@@ -31,7 +31,7 @@ private:
     QueryTerm                  _termB;
     const fef::MatchData      *_md;
 
-    virtual void handle_bind_match_data(fef::MatchData &md) override;
+    virtual void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     TermDistanceExecutor(const fef::IQueryEnvironment & env,
diff --git a/searchlib/src/vespa/searchlib/features/termeditdistancefeature.cpp b/searchlib/src/vespa/searchlib/features/termeditdistancefeature.cpp
index 05bdbb4475b..5990d62cb25 100644
--- a/searchlib/src/vespa/searchlib/features/termeditdistancefeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/termeditdistancefeature.cpp
@@ -156,7 +156,7 @@ TermEditDistanceExecutor::execute(uint32_t docId)
 }
 
 void
-TermEditDistanceExecutor::handle_bind_match_data(fef::MatchData &md)
+TermEditDistanceExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/termeditdistancefeature.h b/searchlib/src/vespa/searchlib/features/termeditdistancefeature.h
index 07d625726e0..ea5974495ea 100644
--- a/searchlib/src/vespa/searchlib/features/termeditdistancefeature.h
+++ b/searchlib/src/vespa/searchlib/features/termeditdistancefeature.h
@@ -88,7 +88,7 @@ private:
      */
     void logRow(const std::vector<TedCell> &row, size_t numCols);
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 
 private:
     const TermEditDistanceConfig             &_config;       // The config for this executor.
diff --git a/searchlib/src/vespa/searchlib/features/text_similarity_feature.cpp b/searchlib/src/vespa/searchlib/features/text_similarity_feature.cpp
index 31876e4f1c9..a50f042b552 100644
--- a/searchlib/src/vespa/searchlib/features/text_similarity_feature.cpp
+++ b/searchlib/src/vespa/searchlib/features/text_similarity_feature.cpp
@@ -158,7 +158,7 @@ TextSimilarityExecutor::execute(uint32_t docId)
 }
 
 void
-TextSimilarityExecutor::handle_bind_match_data(fef::MatchData &md)
+TextSimilarityExecutor::handle_bind_match_data(const fef::MatchData &md)
 {
     _md = &md;
 }
diff --git a/searchlib/src/vespa/searchlib/features/text_similarity_feature.h b/searchlib/src/vespa/searchlib/features/text_similarity_feature.h
index e948589fc97..a660f3e3e30 100644
--- a/searchlib/src/vespa/searchlib/features/text_similarity_feature.h
+++ b/searchlib/src/vespa/searchlib/features/text_similarity_feature.h
@@ -35,7 +35,7 @@ private:
     vespalib::PriorityQueue<Item> _queue;
     const fef::MatchData         *_md;
 
-    void handle_bind_match_data(fef::MatchData &md) override;
+    void handle_bind_match_data(const fef::MatchData &md) override;
 
 public:
     TextSimilarityExecutor(const fef::IQueryEnvironment &env, uint32_t field_id);
diff --git a/searchlib/src/vespa/searchlib/fef/featureexecutor.cpp b/searchlib/src/vespa/searchlib/fef/featureexecutor.cpp
index f8268d66e47..02d69fbc5ca 100644
--- a/searchlib/src/vespa/searchlib/fef/featureexecutor.cpp
+++ b/searchlib/src/vespa/searchlib/fef/featureexecutor.cpp
@@ -28,7 +28,7 @@ FeatureExecutor::handle_bind_outputs(vespalib::ArrayRef<NumberOrObject>)
 }
 
 void
-FeatureExecutor::handle_bind_match_data(MatchData &)
+FeatureExecutor::handle_bind_match_data(const MatchData &)
 {
 }
 
@@ -47,7 +47,7 @@ FeatureExecutor::bind_outputs(vespalib::ArrayRef<NumberOrObject> outputs)
 }
 
 void
-FeatureExecutor::bind_match_data(MatchData &md)
+FeatureExecutor::bind_match_data(const MatchData &md)
 {
     handle_bind_match_data(md);
 }
diff --git a/searchlib/src/vespa/searchlib/fef/featureexecutor.h b/searchlib/src/vespa/searchlib/fef/featureexecutor.h
index 1d8e4bff0c4..c8219fada3b 100644
--- a/searchlib/src/vespa/searchlib/fef/featureexecutor.h
+++ b/searchlib/src/vespa/searchlib/fef/featureexecutor.h
@@ -98,7 +98,7 @@ private:
 protected:
     virtual void handle_bind_inputs(vespalib::ConstArrayRef<LazyValue> inputs);
     virtual void handle_bind_outputs(vespalib::ArrayRef<NumberOrObject> outputs);
-    virtual void handle_bind_match_data(MatchData &md);
+    virtual void handle_bind_match_data(const MatchData &md);
 
     /**
      * Execute this feature executor for the given document.
@@ -117,7 +117,7 @@ public:
     // bind order per executor: inputs, outputs, match_data
     void bind_inputs(vespalib::ConstArrayRef<LazyValue> inputs);
     void bind_outputs(vespalib::ArrayRef<NumberOrObject> outputs);
-    void bind_match_data(MatchData &md);
+    void bind_match_data(const MatchData &md);
 
     const Inputs &inputs() const { return _inputs; }
     const Outputs &outputs() const { return _outputs; }
diff --git a/searchlib/src/vespa/searchlib/fef/featureoverrider.cpp b/searchlib/src/vespa/searchlib/fef/featureoverrider.cpp
index ad623c65c07..5209065fd62 100644
--- a/searchlib/src/vespa/searchlib/fef/featureoverrider.cpp
+++ b/searchlib/src/vespa/searchlib/fef/featureoverrider.cpp
@@ -40,7 +40,7 @@ FeatureOverrider::execute(uint32_t docId)
 }
 
 void
-FeatureOverrider::handle_bind_match_data(MatchData &md)
+FeatureOverrider::handle_bind_match_data(const MatchData &md)
 {
     _executor.bind_match_data(md);
 }
diff --git a/searchlib/src/vespa/searchlib/fef/featureoverrider.h b/searchlib/src/vespa/searchlib/fef/featureoverrider.h
index 3f2075ffbcb..89c397abfdb 100644
--- a/searchlib/src/vespa/searchlib/fef/featureoverrider.h
+++ b/searchlib/src/vespa/searchlib/fef/featureoverrider.h
@@ -24,7 +24,7 @@ private:
     uint32_t            _outputIdx;
     feature_t           _value;
 
-    virtual void handle_bind_match_data(MatchData &md) override;
+    virtual void handle_bind_match_data(const MatchData &md) override;
     virtual void handle_bind_inputs(vespalib::ConstArrayRef<LazyValue> inputs) override;
     virtual void handle_bind_outputs(vespalib::ArrayRef<NumberOrObject> outputs) override;
 
diff --git a/searchlib/src/vespa/searchlib/fef/matchdata.cpp b/searchlib/src/vespa/searchlib/fef/matchdata.cpp
index 4ce2a7c9299..0c589749112 100644
--- a/searchlib/src/vespa/searchlib/fef/matchdata.cpp
+++ b/searchlib/src/vespa/searchlib/fef/matchdata.cpp
@@ -11,6 +11,15 @@ MatchData::MatchData(const Params &cparams)
 {
 }
 
+void
+MatchData::soft_reset()
+{
+    for (auto &tfmd: _termFields) {
+        tfmd.resetOnlyDocId(TermFieldMatchData::invalidId()).tagAsNeeded();
+    }
+    _termwise_limit = 1.0;
+}
+
 MatchData::UP
 MatchData::makeTestInstance(uint32_t numTermFields, uint32_t fieldIdLimit)
 {
diff --git a/searchlib/src/vespa/searchlib/fef/matchdata.h b/searchlib/src/vespa/searchlib/fef/matchdata.h
index 472b34a823f..5b06f4d37e0 100644
--- a/searchlib/src/vespa/searchlib/fef/matchdata.h
+++ b/searchlib/src/vespa/searchlib/fef/matchdata.h
@@ -58,6 +58,15 @@ public:
      **/
     explicit MatchData(const Params &cparams);
 
+    /**
+     * Reset this match data in such a way that it can be re-used with
+     * either the same search iterator tree or with a new search
+     * iterator tree where the only difference in interaction with the
+     * match data is which terms are unpacked. Note that this will
+     * reset some properties, but not all. Use with caution.
+     **/
+    void soft_reset();
+
     MatchData(const MatchData &rhs) = delete;
     MatchData & operator=(const MatchData &rhs) = delete;
 
diff --git a/searchlib/src/vespa/searchlib/fef/rank_program.cpp b/searchlib/src/vespa/searchlib/fef/rank_program.cpp
index fa4582d46b7..33a65b48a1c 100644
--- a/searchlib/src/vespa/searchlib/fef/rank_program.cpp
+++ b/searchlib/src/vespa/searchlib/fef/rank_program.cpp
@@ -109,7 +109,7 @@ RankProgram::run_const(FeatureExecutor *executor)
 }
 
 void
-RankProgram::unbox(BlueprintResolver::FeatureRef seed)
+RankProgram::unbox(BlueprintResolver::FeatureRef seed, const MatchData &md)
 {
     FeatureExecutor *input_executor = _executors[seed.executor];
     const NumberOrObject *input_value = input_executor->outputs().get_raw(seed.output);
@@ -122,7 +122,7 @@ RankProgram::unbox(BlueprintResolver::FeatureRef seed)
         FeatureExecutor &unboxer = _hot_stash.create<UnboxingExecutor>();        
         unboxer.bind_inputs(inputs);
         unboxer.bind_outputs(outputs);
-        unboxer.bind_match_data(*_match_data);
+        unboxer.bind_match_data(md);
         _unboxed_seeds.emplace(input_value, LazyValue(&outputs[0], &unboxer));
     }
 }
@@ -153,7 +153,6 @@ RankProgram::resolve(const BlueprintResolver::FeatureMap &features, bool unbox_s
 
 RankProgram::RankProgram(BlueprintResolver::SP resolver)
     : _resolver(resolver),
-      _match_data(),
       _hot_stash(32768),
       _cold_stash(),
       _executors(),
@@ -165,12 +164,11 @@ RankProgram::RankProgram(BlueprintResolver::SP resolver)
 RankProgram::~RankProgram() {}
 
 void
-RankProgram::setup(const MatchDataLayout &mdl_in,
+RankProgram::setup(const MatchData &md,
                    const IQueryEnvironment &queryEnv,
                    const Properties &featureOverrides)
 {
     assert(_executors.empty());
-    _match_data = mdl_in.createMatchData();
     std::vector<Override> overrides = prepare_overrides(_resolver->getFeatureMap(), featureOverrides);
     auto override = overrides.begin();
     auto override_end = overrides.end();
@@ -204,7 +202,7 @@ RankProgram::setup(const MatchDataLayout &mdl_in,
         }
         executor->bind_inputs(inputs);
         executor->bind_outputs(outputs);
-        executor->bind_match_data(*_match_data);
+        executor->bind_match_data(md);
         _executors.push_back(executor);
         if (is_const) {
             run_const(executor);
@@ -213,7 +211,7 @@ RankProgram::setup(const MatchDataLayout &mdl_in,
     for (const auto &seed_entry: _resolver->getSeedMap()) {
         auto seed = seed_entry.second;
         if (specs[seed.executor].output_types[seed.output]) {
-            unbox(seed);
+            unbox(seed, md);
         }
     }
     assert(_executors.size() == specs.size());
diff --git a/searchlib/src/vespa/searchlib/fef/rank_program.h b/searchlib/src/vespa/searchlib/fef/rank_program.h
index 7cf593e4a4e..3a92fc874a4 100644
--- a/searchlib/src/vespa/searchlib/fef/rank_program.h
+++ b/searchlib/src/vespa/searchlib/fef/rank_program.h
@@ -6,7 +6,6 @@
 #include "featureexecutor.h"
 #include "properties.h"
 #include "matchdata.h"
-#include "matchdatalayout.h"
 #include "feature_resolver.h"
 #include <vespa/vespalib/stllike/string.h>
 #include <vespa/vespalib/util/array.h>
@@ -21,11 +20,10 @@ namespace fef {
  * values. In order to access (and thereby calculate) output features
  * you typically use the get_seeds function to resolve the predefined
  * set of output features. Each feature value will be wrapped in a
- * LazyValue object that can be realized for a specific docid. The
- * rank program also owns the MatchData used to store unpacked
- * term-field match information. Note that you need unpack any
- * relevant posting information into the MatchData object before
- * trying to resolve lazy values.
+ * LazyValue object that can be realized for a specific docid. Note
+ * that you need unpack any relevant posting information into the
+ * MatchData object passed to the setup function before trying to
+ * resolve lazy values.
  **/
 class RankProgram
 {
@@ -37,7 +35,6 @@ private:
     using ValueSet = std::set<const NumberOrObject *>;
 
     BlueprintResolver::SP            _resolver;
-    MatchData::UP                    _match_data;
     vespalib::Stash                  _hot_stash;
     vespalib::Stash                  _cold_stash;
     std::vector<FeatureExecutor *>   _executors;
@@ -47,7 +44,7 @@ private:
     bool check_const(const NumberOrObject *value) const { return (_is_const.count(value) == 1); }
     bool check_const(FeatureExecutor *executor, const std::vector<BlueprintResolver::FeatureRef> &inputs) const;
     void run_const(FeatureExecutor *executor);
-    void unbox(BlueprintResolver::FeatureRef seed);
+    void unbox(BlueprintResolver::FeatureRef seed, const MatchData &md);
     FeatureResolver resolve(const BlueprintResolver::FeatureMap &features, bool unbox_seeds) const;
 
 public:
@@ -66,21 +63,13 @@ public:
     /**
      * Set up this rank program by creating the needed feature
      * executors and wiring them together. This function will also
-     * create the MatchData to be used for iterator unpacking as well
-     * as pre-calculating all constant features.
+     * pre-calculate all constant features.
      **/
-    void setup(const MatchDataLayout &mdl,
+    void setup(const MatchData &md,
                const IQueryEnvironment &queryEnv,
                const Properties &featureOverrides = Properties());
 
     /**
-     * Expose the MatchData used when creating search iterators as it
-     * is where all iterators should unpack their match information.
-     **/
-    MatchData &match_data() { return *_match_data; }
-    const MatchData &match_data() const { return *_match_data; }
-
-    /**
      * Obtain the names and storage locations of all seed features for
      * this rank program. Programs for ranking phases will only have a
      * single seed while programs used for summary features or
diff --git a/searchlib/src/vespa/searchlib/fef/termfieldmatchdata.h b/searchlib/src/vespa/searchlib/fef/termfieldmatchdata.h
index 2d91764f7c9..018af889557 100644
--- a/searchlib/src/vespa/searchlib/fef/termfieldmatchdata.h
+++ b/searchlib/src/vespa/searchlib/fef/termfieldmatchdata.h
@@ -258,6 +258,13 @@ public:
     }
 
     /**
+     * Tag that this instance is used for ranking.
+     */
+    void tagAsNeeded() {
+        _fieldId = _fieldId & ~0x2000;
+    }
+
+    /**
      * Special docId value indicating that no data has been saved yet.
      * This should match (or be above) endId() in search::queryeval::SearchIterator.
      *
diff --git a/searchlib/src/vespa/searchlib/fef/test/featuretest.cpp b/searchlib/src/vespa/searchlib/fef/test/featuretest.cpp
index 2652abf97a4..e5a6232ed54 100644
--- a/searchlib/src/vespa/searchlib/fef/test/featuretest.cpp
+++ b/searchlib/src/vespa/searchlib/fef/test/featuretest.cpp
@@ -22,6 +22,7 @@ FeatureTest::FeatureTest(BlueprintFactory &factory,
     _layout(layout),
     _overrides(overrides),
     _resolver(new BlueprintResolver(factory, indexEnv)),
+    _match_data(_layout.createMatchData()),
     _rankProgram(new RankProgram(_resolver)),
     _doneSetup(false)
 {
@@ -42,6 +43,7 @@ FeatureTest::FeatureTest(BlueprintFactory &factory,
     _layout(layout),
     _overrides(overrides),
     _resolver(new BlueprintResolver(factory, indexEnv)),
+    _match_data(_layout.createMatchData()),
     _rankProgram(new RankProgram(_resolver)),
     _doneSetup(false)
 {
@@ -68,7 +70,7 @@ FeatureTest::setup()
         return false;
     }
 
-    _rankProgram->setup(_layout, _queryEnv, _overrides);
+    _rankProgram->setup(*_match_data, _queryEnv, _overrides);
     _doneSetup = true;
     return true;
 }
@@ -77,7 +79,7 @@ MatchDataBuilder::UP
 FeatureTest::createMatchDataBuilder()
 {
     if (_doneSetup) {
-        return MatchDataBuilder::UP(new MatchDataBuilder(_queryEnv, _rankProgram->match_data()));
+        return MatchDataBuilder::UP(new MatchDataBuilder(_queryEnv, *_match_data));
     }
     LOG(warning, "Match data not initialized.");
     return MatchDataBuilder::UP();
@@ -135,6 +137,7 @@ void
 FeatureTest::clear()
 {
     _resolver = BlueprintResolver::SP(new BlueprintResolver(_factory, _indexEnv));
+    _match_data = _layout.createMatchData();
     _rankProgram.reset(new RankProgram(_resolver));
     _doneSetup = false;
 }
diff --git a/searchlib/src/vespa/searchlib/fef/test/featuretest.h b/searchlib/src/vespa/searchlib/fef/test/featuretest.h
index 2bce63d357d..e354884c110 100644
--- a/searchlib/src/vespa/searchlib/fef/test/featuretest.h
+++ b/searchlib/src/vespa/searchlib/fef/test/featuretest.h
@@ -116,6 +116,7 @@ private:
     MatchDataLayout                        &_layout;
     const Properties                       &_overrides;
     BlueprintResolver::SP                   _resolver;
+    MatchData::UP                           _match_data;
     RankProgram::UP                         _rankProgram;
     bool                                    _doneSetup;
 
diff --git a/searchlib/src/vespa/searchlib/queryeval/termwise_search.cpp b/searchlib/src/vespa/searchlib/queryeval/termwise_search.cpp
index 13b1c8f1da6..e7df5aa6bae 100644
--- a/searchlib/src/vespa/searchlib/queryeval/termwise_search.cpp
+++ b/searchlib/src/vespa/searchlib/queryeval/termwise_search.cpp
@@ -11,17 +11,27 @@ template <bool IS_STRICT>
 struct TermwiseSearch : public SearchIterator {
 
     SearchIterator::UP search;
-    BitVector::UP  result;
+    BitVector::UP      result;
+    uint32_t           my_beginid;
+    uint32_t           my_first_hit;
+
+    bool same_range(uint32_t beginid, uint32_t endid) const {
+        return ((beginid == my_beginid) && endid == getEndId());
+    }
 
     TermwiseSearch(SearchIterator::UP search_in)
-        : search(std::move(search_in)), result() {}
+        : search(std::move(search_in)), result(), my_beginid(0), my_first_hit(0) {}
 
     Trinary is_strict() const override { return IS_STRICT ? Trinary::True : Trinary::False; }
     void initRange(uint32_t beginid, uint32_t endid) override {
-        SearchIterator::initRange(beginid, endid);
-        search->initRange(beginid, endid);
-        setDocId(std::max(getDocId(), search->getDocId()));
-        result = search->get_hits(beginid);
+        if (!same_range(beginid, endid)) {
+            my_beginid = beginid;
+            SearchIterator::initRange(beginid, endid);
+            search->initRange(beginid, endid);
+            my_first_hit = std::max(getDocId(), search->getDocId());
+            result = search->get_hits(beginid);
+        }
+        setDocId(my_first_hit);
     }
     void doSeek(uint32_t docid) override {
         if (__builtin_expect(isAtEnd(docid), false)) {