Merge pull request #15678 from vespa-engine/havardpe/remove-engine-or-factory

remove EngineOrFactory

27 files changed, 73 insertions, 356 deletions

diff --git a/document/src/vespa/document/fieldvalue/tensorfieldvalue.cpp b/document/src/vespa/document/fieldvalue/tensorfieldvalue.cpp
index 183caa7e3e0..cc3aed67387 100644
--- a/document/src/vespa/document/fieldvalue/tensorfieldvalue.cpp
+++ b/document/src/vespa/document/fieldvalue/tensorfieldvalue.cpp
@@ -4,14 +4,14 @@
 #include <vespa/document/base/exceptions.h>
 #include <vespa/document/datatype/tensor_data_type.h>
 #include <vespa/vespalib/util/xmlstream.h>
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
 #include <vespa/eval/eval/tensor_spec.h>
 #include <vespa/eval/eval/value_codec.h>
 #include <vespa/eval/eval/value.h>
 #include <ostream>
 #include <cassert>
 
-using vespalib::eval::EngineOrFactory;
+using vespalib::eval::FastValueBuilderFactory;
 using vespalib::eval::TensorSpec;
 using vespalib::eval::ValueType;
 using namespace vespalib::xml;
@@ -51,7 +51,7 @@ TensorFieldValue::TensorFieldValue(const TensorFieldValue &rhs)
       _altered(true)
 {
     if (rhs._tensor) {
-        _tensor = EngineOrFactory::get().copy(*rhs._tensor);
+        _tensor = FastValueBuilderFactory::get().copy(*rhs._tensor);
     }
 }
 
@@ -78,7 +78,7 @@ TensorFieldValue::operator=(const TensorFieldValue &rhs)
         if (&_dataType == &rhs._dataType || !rhs._tensor ||
             _dataType.isAssignableType(rhs._tensor->type())) {
             if (rhs._tensor) {
-                _tensor = EngineOrFactory::get().copy(*rhs._tensor);
+                _tensor = FastValueBuilderFactory::get().copy(*rhs._tensor);
             } else {
                 _tensor.reset();
             }
@@ -109,7 +109,7 @@ TensorFieldValue::make_empty_if_not_existing()
 {
     if (!_tensor) {
         TensorSpec empty_spec(_dataType.getTensorType().to_spec());
-        _tensor = EngineOrFactory::get().from_spec(empty_spec);
+        _tensor = value_from_spec(empty_spec, FastValueBuilderFactory::get());
     }
 }
 
diff --git a/document/src/vespa/document/serialization/vespadocumentdeserializer.cpp b/document/src/vespa/document/serialization/vespadocumentdeserializer.cpp
index eaa5a484ad1..6567b8cb6b5 100644
--- a/document/src/vespa/document/serialization/vespadocumentdeserializer.cpp
+++ b/document/src/vespa/document/serialization/vespadocumentdeserializer.cpp
@@ -22,7 +22,8 @@
 #include <vespa/vespalib/data/slime/slime.h>
 #include <vespa/vespalib/stllike/asciistream.h>
 #include <vespa/vespalib/util/backtrace.h>
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
+#include <vespa/eval/eval/value_codec.h>
 #include <vespa/eval/eval/value.h>
 #include <vespa/document/util/serializableexceptions.h>
 #include <vespa/document/base/exceptions.h>
@@ -41,7 +42,7 @@ using vespalib::nbostream;
 using vespalib::Memory;
 using vespalib::stringref;
 using vespalib::compression::CompressionConfig;
-using vespalib::eval::EngineOrFactory;
+using vespalib::eval::FastValueBuilderFactory;
 
 namespace document {
 
@@ -372,7 +373,7 @@ VespaDocumentDeserializer::readTensor()
     std::unique_ptr<vespalib::eval::Value> tensor;
     if (length != 0) {
         nbostream wrapStream(_stream.peek(), length);
-        tensor = EngineOrFactory::get().decode(wrapStream);
+        tensor = vespalib::eval::decode_value(wrapStream, FastValueBuilderFactory::get());
         if (wrapStream.size() != 0) {
             throw DeserializeException("Leftover bytes deserializing tensor field value.", VESPA_STRLOC);
         }
diff --git a/document/src/vespa/document/update/tensor_add_update.cpp b/document/src/vespa/document/update/tensor_add_update.cpp
index d71ab7d922c..c9ffad2a789 100644
--- a/document/src/vespa/document/update/tensor_add_update.cpp
+++ b/document/src/vespa/document/update/tensor_add_update.cpp
@@ -9,7 +9,7 @@
 #include <vespa/document/serialization/vespadocumentdeserializer.h>
 #include <vespa/document/util/serializableexceptions.h>
 #include <vespa/eval/eval/value.h>
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
 #include <vespa/eval/tensor/partial_update.h>
 #include <vespa/vespalib/objects/nbostream.h>
 #include <vespa/vespalib/stllike/asciistream.h>
@@ -20,7 +20,7 @@
 using vespalib::IllegalArgumentException;
 using vespalib::IllegalStateException;
 using vespalib::make_string;
-using vespalib::eval::EngineOrFactory;
+using vespalib::eval::FastValueBuilderFactory;
 using vespalib::tensor::TensorPartialUpdate;
 
 namespace document {
@@ -86,8 +86,8 @@ TensorAddUpdate::applyTo(const vespalib::eval::Value &tensor) const
 {
     auto addTensor = _tensor->getAsTensorPtr();
     if (addTensor) {
-        auto engine = EngineOrFactory::get();
-        return TensorPartialUpdate::add(tensor, *addTensor, engine);
+        const auto &factory = FastValueBuilderFactory::get();
+        return TensorPartialUpdate::add(tensor, *addTensor, factory);
     }
     return {};
 }
diff --git a/document/src/vespa/document/update/tensor_modify_update.cpp b/document/src/vespa/document/update/tensor_modify_update.cpp
index 970550b7c88..4da93d0ae46 100644
--- a/document/src/vespa/document/update/tensor_modify_update.cpp
+++ b/document/src/vespa/document/update/tensor_modify_update.cpp
@@ -10,7 +10,7 @@
 #include <vespa/document/util/serializableexceptions.h>
 #include <vespa/eval/eval/operation.h>
 #include <vespa/eval/eval/value.h>
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
 #include <vespa/eval/tensor/partial_update.h>
 #include <vespa/vespalib/objects/nbostream.h>
 #include <vespa/vespalib/stllike/asciistream.h>
@@ -22,7 +22,7 @@ using vespalib::IllegalArgumentException;
 using vespalib::IllegalStateException;
 using vespalib::make_string;
 using vespalib::eval::ValueType;
-using vespalib::eval::EngineOrFactory;
+using vespalib::eval::FastValueBuilderFactory;
 using vespalib::tensor::TensorPartialUpdate;
 
 using join_fun_t = double (*)(double, double);
@@ -163,8 +163,8 @@ TensorModifyUpdate::applyTo(const vespalib::eval::Value &tensor) const
 {
     auto cellsTensor = _tensor->getAsTensorPtr();
     if (cellsTensor) {
-        auto engine = EngineOrFactory::get();
-        return TensorPartialUpdate::modify(tensor, getJoinFunction(_operation), *cellsTensor, engine);
+        const auto &factory = FastValueBuilderFactory::get();
+        return TensorPartialUpdate::modify(tensor, getJoinFunction(_operation), *cellsTensor, factory);
     }
     return {};
 }
@@ -213,8 +213,7 @@ verifyCellsTensorIsSparse(const vespalib::eval::Value *cellsTensor)
     if (cellsTensor == nullptr) {
         return;
     }
-    auto engine = EngineOrFactory::get();
-    if (TensorPartialUpdate::check_suitably_sparse(*cellsTensor, engine)) {
+    if (cellsTensor->type().is_sparse()) {
         return;
     }
     vespalib::string err = make_string("Expected cells tensor to be sparse, but has type '%s'",
diff --git a/document/src/vespa/document/update/tensor_remove_update.cpp b/document/src/vespa/document/update/tensor_remove_update.cpp
index f04728e95a4..7b81581aeed 100644
--- a/document/src/vespa/document/update/tensor_remove_update.cpp
+++ b/document/src/vespa/document/update/tensor_remove_update.cpp
@@ -6,7 +6,7 @@
 #include <vespa/document/fieldvalue/document.h>
 #include <vespa/document/fieldvalue/tensorfieldvalue.h>
 #include <vespa/document/serialization/vespadocumentdeserializer.h>
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
 #include <vespa/eval/tensor/partial_update.h>
 #include <vespa/eval/eval/value.h>
 #include <vespa/vespalib/objects/nbostream.h>
@@ -19,7 +19,7 @@ using vespalib::IllegalStateException;
 using vespalib::make_string;
 using vespalib::eval::Value;
 using vespalib::eval::ValueType;
-using vespalib::eval::EngineOrFactory;
+using vespalib::eval::FastValueBuilderFactory;
 using vespalib::tensor::TensorPartialUpdate;
 
 namespace document {
@@ -110,8 +110,8 @@ TensorRemoveUpdate::applyTo(const vespalib::eval::Value &tensor) const
 {
     auto addressTensor = _tensor->getAsTensorPtr();
     if (addressTensor) {
-        auto engine = EngineOrFactory::get();
-        return TensorPartialUpdate::remove(tensor, *addressTensor, engine);
+        const auto &factory = FastValueBuilderFactory::get();
+        return TensorPartialUpdate::remove(tensor, *addressTensor, factory);
     }
     return {};
 }
@@ -160,8 +160,7 @@ verifyAddressTensorIsSparse(const Value *addressTensor)
     if (addressTensor == nullptr) {
         throw IllegalStateException("Address tensor is not set", VESPA_STRLOC);
     }
-    auto engine = EngineOrFactory::get();
-    if (TensorPartialUpdate::check_suitably_sparse(*addressTensor, engine)) {
+    if (addressTensor->type().is_sparse()) {
         return;
     }
     auto err = make_string("Expected address tensor to be sparse, but has type '%s'",
diff --git a/eval/CMakeLists.txt b/eval/CMakeLists.txt
index c4fd211897b..d9dc7e587b0 100644
--- a/eval/CMakeLists.txt
+++ b/eval/CMakeLists.txt
@@ -15,7 +15,6 @@ vespa_define_module(
     src/tests/eval/array_array_map
     src/tests/eval/compile_cache
     src/tests/eval/compiled_function
-    src/tests/eval/engine_or_factory
     src/tests/eval/fast_sparse_map
     src/tests/eval/fast_value
     src/tests/eval/function
diff --git a/eval/src/tests/eval/engine_or_factory/CMakeLists.txt b/eval/src/tests/eval/engine_or_factory/CMakeLists.txt
deleted file mode 100644
index f0bd0f63251..00000000000
--- a/eval/src/tests/eval/engine_or_factory/CMakeLists.txt
+++ /dev/null
@@ -1,17 +0,0 @@
-# Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-vespa_add_executable(eval_engine_or_factory_test_app TEST
-    SOURCES
-    engine_or_factory_test.cpp
-    DEPENDS
-    vespaeval
-    GTest::GTest
-)
-vespa_add_test(NAME eval_engine_or_factory_test_app COMMAND eval_engine_or_factory_test_app)
-vespa_add_executable(eval_engine_or_factory_override_test_app TEST
-    SOURCES
-    engine_or_factory_override_test.cpp
-    DEPENDS
-    vespaeval
-    GTest::GTest
-)
-vespa_add_test(NAME eval_engine_or_factory_override_test_app COMMAND eval_engine_or_factory_override_test_app)
diff --git a/eval/src/tests/eval/engine_or_factory/engine_or_factory_override_test.cpp b/eval/src/tests/eval/engine_or_factory/engine_or_factory_override_test.cpp
deleted file mode 100644
index b06e2723d74..00000000000
--- a/eval/src/tests/eval/engine_or_factory/engine_or_factory_override_test.cpp
+++ /dev/null
@@ -1,24 +0,0 @@
-// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-
-#include <vespa/eval/eval/engine_or_factory.h>
-#include <vespa/eval/eval/fast_value.h>
-#include <vespa/eval/eval/simple_value.h>
-#include <vespa/vespalib/util/exceptions.h>
-#include <vespa/vespalib/gtest/gtest.h>
-
-using namespace vespalib::eval;
-
-TEST(EngineOrFactoryOverrideTest, set_can_override_get_result) {
-    EngineOrFactory::set(SimpleValueBuilderFactory::get());
-    EXPECT_EQ(EngineOrFactory::get().to_string(), "SimpleValueBuilderFactory");
-}
-
-TEST(EngineOrFactoryOverrideTest, set_with_same_value_is_allowed) {
-    EngineOrFactory::set(SimpleValueBuilderFactory::get());
-}
-
-TEST(EngineOrFactoryOverrideTest, set_with_another_value_is_not_allowed) {
-    EXPECT_THROW(EngineOrFactory::set(FastValueBuilderFactory::get()), vespalib::IllegalStateException);
-}
-
-GTEST_MAIN_RUN_ALL_TESTS()
diff --git a/eval/src/tests/eval/engine_or_factory/engine_or_factory_test.cpp b/eval/src/tests/eval/engine_or_factory/engine_or_factory_test.cpp
deleted file mode 100644
index 26e8e8e75ec..00000000000
--- a/eval/src/tests/eval/engine_or_factory/engine_or_factory_test.cpp
+++ /dev/null
@@ -1,23 +0,0 @@
-// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-
-#include <vespa/eval/eval/engine_or_factory.h>
-#include <vespa/eval/eval/fast_value.h>
-#include <vespa/eval/eval/simple_value.h>
-#include <vespa/vespalib/util/exceptions.h>
-#include <vespa/vespalib/gtest/gtest.h>
-
-using namespace vespalib::eval;
-
-TEST(EngineOrFactoryTest, default_is_fast_value_builder_factory) {
-    EXPECT_EQ(EngineOrFactory::get().to_string(), "FastValueBuilderFactory");
-}
-
-TEST(EngineOrFactoryTest, set_with_same_value_is_allowed) {
-    EngineOrFactory::set(FastValueBuilderFactory::get());
-}
-
-TEST(EngineOrFactoryTest, set_with_another_value_is_not_allowed) {
-    EXPECT_THROW(EngineOrFactory::set(SimpleValueBuilderFactory::get()), vespalib::IllegalStateException);
-}
-
-GTEST_MAIN_RUN_ALL_TESTS()
diff --git a/eval/src/vespa/eval/eval/CMakeLists.txt b/eval/src/vespa/eval/eval/CMakeLists.txt
index 66c807565cc..d32841520a6 100644
--- a/eval/src/vespa/eval/eval/CMakeLists.txt
+++ b/eval/src/vespa/eval/eval/CMakeLists.txt
@@ -9,7 +9,6 @@ vespa_add_library(eval_eval OBJECT
     compile_tensor_function.cpp
     delete_node.cpp
     double_value_builder.cpp
-    engine_or_factory.cpp
     fast_forest.cpp
     fast_sparse_map.cpp
     fast_value.cpp
diff --git a/eval/src/vespa/eval/eval/engine_or_factory.cpp b/eval/src/vespa/eval/eval/engine_or_factory.cpp
deleted file mode 100644
index 5b46fd61951..00000000000
--- a/eval/src/vespa/eval/eval/engine_or_factory.cpp
+++ /dev/null
@@ -1,116 +0,0 @@
-// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-
-#include "engine_or_factory.h"
-#include "fast_value.h"
-#include "simple_value.h"
-#include "value_codec.h"
-#include <vespa/eval/instruction/generic_concat.h>
-#include <vespa/eval/instruction/generic_join.h>
-#include <vespa/eval/instruction/generic_map.h>
-#include <vespa/eval/instruction/generic_merge.h>
-#include <vespa/eval/instruction/generic_reduce.h>
-#include <vespa/eval/instruction/generic_rename.h>
-#include "tensor_engine.h"
-#include <vespa/vespalib/data/memory.h>
-#include <vespa/vespalib/objects/nbostream.h>
-#include <vespa/vespalib/util/exceptions.h>
-#include <vespa/vespalib/util/stash.h>
-#include <vespa/vespalib/util/stringfmt.h>
-
-using vespalib::make_string_short::fmt;
-
-using namespace vespalib::eval::instruction;
-
-namespace vespalib::eval {
-
-EngineOrFactory EngineOrFactory::_default{FastValueBuilderFactory::get()};
-
-
-EngineOrFactory
-EngineOrFactory::get_shared(EngineOrFactory hint)
-{
-    static EngineOrFactory shared{hint};
-    return shared;
-}
-
-TensorSpec
-EngineOrFactory::to_spec(const Value &value) const
-{
-    if (is_engine()) {
-        return engine().to_spec(value);
-    } else {
-        return factory(), spec_from_value(value);
-    }
-}
-
-std::unique_ptr<Value>
-EngineOrFactory::from_spec(const TensorSpec &spec) const
-{
-    if (is_engine()) {
-        return engine().from_spec(spec);
-    } else {
-        return value_from_spec(spec, factory());
-    }
-}
-
-void
-EngineOrFactory::encode(const Value &value, nbostream &output) const
-{
-    if (is_engine()) {
-        return engine().encode(value, output);
-    } else {
-        return factory(), encode_value(value, output);
-    }
-}
-
-std::unique_ptr<Value>
-EngineOrFactory::decode(nbostream &input) const
-{
-    if (is_engine()) {
-        return engine().decode(input);
-    } else {
-        return decode_value(input, factory());
-    }
-}
-
-std::unique_ptr<Value>
-EngineOrFactory::copy(const Value &value)
-{
-    nbostream stream;
-    encode(value, stream);
-    return decode(stream);
-}
-
-void
-EngineOrFactory::set(EngineOrFactory wanted)
-{
-    assert(wanted.is_factory());
-    auto engine = get_shared(wanted);
-    if (engine._value != wanted._value) {
-        auto msg = fmt("EngineOrFactory: trying to set implementation to [%s] when [%s] is already in use",
-                       wanted.to_string().c_str(), engine.to_string().c_str());
-        throw IllegalStateException(msg);
-    }
-}
-
-EngineOrFactory
-EngineOrFactory::get()
-{
-    return get_shared(_default);
-}
-
-vespalib::string
-EngineOrFactory::to_string() const
-{
-    if (is_factory()) {
-        if (&factory() == &FastValueBuilderFactory::get()) {
-            return "FastValueBuilderFactory";
-        }
-        if (&factory() == &SimpleValueBuilderFactory::get()) {
-            return "SimpleValueBuilderFactory";
-        }
-    }
-    return "???";
-}
-
-}
diff --git a/eval/src/vespa/eval/eval/engine_or_factory.h b/eval/src/vespa/eval/eval/engine_or_factory.h
deleted file mode 100644
index 7269f22159d..00000000000
--- a/eval/src/vespa/eval/eval/engine_or_factory.h
+++ /dev/null
@@ -1,56 +0,0 @@
-// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-
-#pragma once
-
-#include "aggr.h"
-#include "tensor_spec.h"
-#include "operation.h"
-#include <variant>
-
-namespace vespalib {
-class Stash;
-class nbostream;
-}
-
-namespace vespalib::eval {
-
-struct TensorEngine;
-struct ValueBuilderFactory;
-struct TensorFunction;
-
-/**
- * This utility class contains a reference to either a TensorEngine or
- * a ValueBuilderFactory. This is needed during a transition period to
- * support both evaluation models. We want to get rid of the
- * TensorEngine concept since using the Value API directly removes the
- * need to constrain operations to only calculate on tensors belonging
- * to the same tensor engine. The factory is a hint to the preferred
- * Value implementation.
- **/
-class EngineOrFactory {
-private:
-    using engine_t = const TensorEngine *;
-    using factory_t = const ValueBuilderFactory *;
-    std::variant<engine_t,factory_t> _value;
-    static EngineOrFactory _default;
-    static EngineOrFactory get_shared(EngineOrFactory hint);
-public:
-    EngineOrFactory(const ValueBuilderFactory &factory_in) : _value(&factory_in) {}
-    bool is_engine() const { return std::holds_alternative<engine_t>(_value); }
-    bool is_factory() const { return std::holds_alternative<factory_t>(_value); }
-    const TensorEngine &engine() const { return *std::get<engine_t>(_value); }
-    const ValueBuilderFactory &factory() const { return *std::get<factory_t>(_value); }
-    // functions that can be called with either engine or factory
-    TensorSpec to_spec(const Value &value) const;
-    std::unique_ptr<Value> from_spec(const TensorSpec &spec) const;
-    void encode(const Value &value, nbostream &output) const;
-    std::unique_ptr<Value> decode(nbostream &input) const;
-    std::unique_ptr<Value> copy(const Value &value);
-    // global switch with default; call set before get to override the default
-    static void set(EngineOrFactory wanted);
-    static EngineOrFactory get();
-    // try to describe the value held by this object as a human-readable string
-    vespalib::string to_string() const;
-};
-
-}
diff --git a/eval/src/vespa/eval/eval/value.cpp b/eval/src/vespa/eval/eval/value.cpp
index 267d2443112..7abc8d568cb 100644
--- a/eval/src/vespa/eval/eval/value.cpp
+++ b/eval/src/vespa/eval/eval/value.cpp
@@ -1,7 +1,9 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 
 #include "value.h"
+#include "value_codec.h"
 #include <vespa/vespalib/util/typify.h>
+#include <vespa/vespalib/objects/nbostream.h>
 
 namespace vespalib {
 namespace eval {
@@ -62,5 +64,13 @@ ValueType ScalarValue<T>::_type = ValueType::make_type(get_cell_type<T>(), {});
 template class ScalarValue<double>;
 template class ScalarValue<float>;
 
+std::unique_ptr<Value>
+ValueBuilderFactory::copy(const Value &value) const
+{
+    nbostream stream;
+    encode_value(value, stream);
+    return decode_value(stream, *this);
+}
+
 } // namespace vespalib::eval
 } // namespace vespalib
diff --git a/eval/src/vespa/eval/eval/value.h b/eval/src/vespa/eval/eval/value.h
index e876ba7b472..cf4e21029fc 100644
--- a/eval/src/vespa/eval/eval/value.h
+++ b/eval/src/vespa/eval/eval/value.h
@@ -198,6 +198,7 @@ struct ValueBuilderFactory {
     {
         return create_value_builder<T>(type, type.count_mapped_dimensions(), type.dense_subspace_size(), 1);
     }
+    std::unique_ptr<Value> copy(const Value &value) const;
     virtual ~ValueBuilderFactory() {}
 protected:
     virtual std::unique_ptr<ValueBuilderBase> create_value_builder_base(const ValueType &type,
diff --git a/eval/src/vespa/eval/tensor/partial_update.cpp b/eval/src/vespa/eval/tensor/partial_update.cpp
index 82cd5553741..0f3ebe9537b 100644
--- a/eval/src/vespa/eval/tensor/partial_update.cpp
+++ b/eval/src/vespa/eval/tensor/partial_update.cpp
@@ -417,42 +417,4 @@ TensorPartialUpdate::remove(const Value &input, const Value &remove_spec, const
             input, remove_spec, factory);
 }
 
-Value::UP
-TensorPartialUpdate::modify(const Value &input, join_fun_t function,
-                            const Value &modifier, EngineOrFactory engine)
-{
-    if (engine.is_engine()) {
-        abort();
-    }
-    return modify(input, function, modifier, engine.factory());
-
-}
-
-Value::UP
-TensorPartialUpdate::add(const Value &input, const Value &add_cells, EngineOrFactory engine)
-{
-    if (engine.is_engine()) {
-        abort();
-    }
-    return add(input, add_cells, engine.factory());
-}
-
-Value::UP
-TensorPartialUpdate::remove(const Value &input, const Value &remove_spec, EngineOrFactory engine)
-{
-    if (engine.is_engine()) {
-        abort();
-    }
-    return remove(input, remove_spec, engine.factory());
-}
-
-bool
-TensorPartialUpdate::check_suitably_sparse(const Value &modifier, const EngineOrFactory engine)
-{
-    if (engine.is_engine()) {
-        abort();
-    }
-    return modifier.type().is_sparse();
-}
-
 } // namespace
diff --git a/eval/src/vespa/eval/tensor/partial_update.h b/eval/src/vespa/eval/tensor/partial_update.h
index 6bbef6a8189..b3e9d32fca8 100644
--- a/eval/src/vespa/eval/tensor/partial_update.h
+++ b/eval/src/vespa/eval/tensor/partial_update.h
@@ -2,7 +2,7 @@
 
 #pragma once
 
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
 #include <vespa/eval/eval/value.h>
 #include <vespa/eval/eval/operation.h>
 
@@ -39,15 +39,6 @@ struct TensorPartialUpdate {
      *  Returns null pointer if these constraints are violated.
      **/
     static Value::UP remove(const Value &input, const Value &remove_spec, const ValueBuilderFactory &factory);
-
-    /* Backwards compatibility adapters. TODO: remove */
-    using EngineOrFactory = vespalib::eval::EngineOrFactory;
-    static Value::UP modify(const Value &input, join_fun_t function,
-                            const Value &modifier, EngineOrFactory factory);
-    static Value::UP add(const Value &input, const Value &add_cells, EngineOrFactory factory);
-    static Value::UP remove(const Value &input, const Value &remove_spec, EngineOrFactory factory);
-    /** Check if the given value can be used as a modifier or remove_spec */
-    static bool check_suitably_sparse(const Value &modifier,  EngineOrFactory factory);
 };
 
 } // namespace
diff --git a/searchcore/src/apps/verify_ranksetup/verify_ranksetup.cpp b/searchcore/src/apps/verify_ranksetup/verify_ranksetup.cpp
index 3c1fc8a4622..559e8fd14cd 100644
--- a/searchcore/src/apps/verify_ranksetup/verify_ranksetup.cpp
+++ b/searchcore/src/apps/verify_ranksetup/verify_ranksetup.cpp
@@ -11,7 +11,8 @@
 #include <vespa/config/common/exceptions.h>
 #include <vespa/eval/eval/tensor_spec.h>
 #include <vespa/eval/eval/value_cache/constant_value.h>
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
+#include <vespa/eval/eval/value_codec.h>
 #include <vespa/searchcommon/common/schemaconfigurer.h>
 #include <vespa/searchcore/config/config-ranking-constants.h>
 #include <vespa/searchcore/config/config-onnx-models.h>
@@ -41,7 +42,7 @@ using vespa::config::search::core::OnnxModelsConfig;
 using vespa::config::search::core::VerifyRanksetupConfig;
 using vespalib::eval::BadConstantValue;
 using vespalib::eval::ConstantValue;
-using vespalib::eval::EngineOrFactory;
+using vespalib::eval::FastValueBuilderFactory;
 using vespalib::eval::SimpleConstantValue;
 using vespalib::eval::TensorSpec;
 using vespalib::eval::Value;
@@ -96,7 +97,7 @@ struct DummyConstantValueRepo : IConstantValueRepo {
         for (const auto &entry: cfg.constant) {
             if (entry.name == name) {
                 try {
-                    auto tensor = EngineOrFactory::get().from_spec(TensorSpec(entry.type));
+                    auto tensor = vespalib::eval::value_from_spec(TensorSpec(entry.type), FastValueBuilderFactory::get());
                     return std::make_unique<SimpleConstantValue>(std::move(tensor));
                 } catch (std::exception &) {
                     return std::make_unique<BadConstantValue>();
diff --git a/searchcore/src/vespa/searchcore/proton/matching/requestcontext.cpp b/searchcore/src/vespa/searchcore/proton/matching/requestcontext.cpp
index 2f6625aaa11..6ad2f69ae7a 100644
--- a/searchcore/src/vespa/searchcore/proton/matching/requestcontext.cpp
+++ b/searchcore/src/vespa/searchcore/proton/matching/requestcontext.cpp
@@ -1,7 +1,8 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 
 #include "requestcontext.h"
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
+#include <vespa/eval/eval/value_codec.h>
 #include <vespa/searchlib/attribute/attributevector.h>
 #include <vespa/searchlib/fef/properties.h>
 #include <vespa/vespalib/objects/nbostream.h>
@@ -10,7 +11,7 @@
 #include <vespa/log/log.h>
 LOG_SETUP(".proton.matching.requestcontext");
 
-using vespalib::eval::EngineOrFactory;
+using vespalib::eval::FastValueBuilderFactory;
 
 namespace proton {
 
@@ -52,7 +53,7 @@ RequestContext::get_query_tensor(const vespalib::string& tensor_name) const
         const vespalib::string& value = property.get();
         vespalib::nbostream stream(value.data(), value.size());
         try {
-            return EngineOrFactory::get().decode(stream);
+            return decode_value(stream, FastValueBuilderFactory::get());
         } catch (vespalib::Exception& ex) {
             LOG(warning, "Query tensor '%s' could not be deserialized: %s",
                 tensor_name.c_str(), ex.getMessage().c_str());
diff --git a/searchcore/src/vespa/searchcore/proton/server/proton.cpp b/searchcore/src/vespa/searchcore/proton/server/proton.cpp
index c2b57734903..dddca6a9ddd 100644
--- a/searchcore/src/vespa/searchcore/proton/server/proton.cpp
+++ b/searchcore/src/vespa/searchcore/proton/server/proton.cpp
@@ -17,8 +17,6 @@
 #include <vespa/document/base/exceptions.h>
 #include <vespa/document/datatype/documenttype.h>
 #include <vespa/document/repo/documenttyperepo.h>
-#include <vespa/eval/eval/engine_or_factory.h>
-#include <vespa/eval/eval/fast_value.h>
 #include <vespa/searchcore/proton/flushengine/flush_engine_explorer.h>
 #include <vespa/searchcore/proton/flushengine/flushengine.h>
 #include <vespa/searchcore/proton/flushengine/tls_stats_factory.h>
@@ -56,7 +54,6 @@ using search::transactionlog::DomainStats;
 using vespa::config::search::core::ProtonConfig;
 using vespa::config::search::core::internal::InternalProtonType;
 using vespalib::compression::CompressionConfig;
-using vespalib::eval::EngineOrFactory;
 
 namespace proton {
 
@@ -74,17 +71,6 @@ convert(InternalProtonType::Packetcompresstype type)
 }
 
 void
-set_tensor_implementation(const ProtonConfig& cfg)
-{
-    if (cfg.tensorImplementation == ProtonConfig::TensorImplementation::TENSOR_ENGINE) {
-        LOG(error, "Old tensor engine implementation no longer available");
-    } else if (cfg.tensorImplementation == ProtonConfig::TensorImplementation::FAST_VALUE) {
-        EngineOrFactory::set(vespalib::eval::FastValueBuilderFactory::get());
-    }
-    LOG(info, "Tensor implementation used: %s", EngineOrFactory::get().to_string().c_str());
-}
-
-void
 setBucketCheckSumType(const ProtonConfig & proton)
 {
     switch (proton.bucketdb.checksumtype) {
@@ -268,7 +254,6 @@ Proton::init(const BootstrapConfig::SP & configSnapshot)
     const ProtonConfig &protonConfig = configSnapshot->getProtonConfig();
     const HwInfo & hwInfo = configSnapshot->getHwInfo();
 
-    set_tensor_implementation(protonConfig);
     setBucketCheckSumType(protonConfig);
     setFS4Compression(protonConfig);
     _diskMemUsageSampler = std::make_unique<DiskMemUsageSampler>(protonConfig.basedir,
diff --git a/searchlib/src/vespa/searchlib/attribute/createsinglestd.cpp b/searchlib/src/vespa/searchlib/attribute/createsinglestd.cpp
index 29033944d4b..ffaec9d0779 100644
--- a/searchlib/src/vespa/searchlib/attribute/createsinglestd.cpp
+++ b/searchlib/src/vespa/searchlib/attribute/createsinglestd.cpp
@@ -7,7 +7,7 @@
 #include "singlenumericattribute.hpp"
 #include "singlestringattribute.h"
 #include "singleboolattribute.h"
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
 #include <vespa/searchlib/tensor/dense_tensor_attribute.h>
 #include <vespa/searchlib/tensor/serialized_tensor_attribute.h>
 #include <vespa/searchlib/tensor/serialized_fast_value_attribute.h>
@@ -47,10 +47,8 @@ AttributeFactory::createSingleStd(stringref name, const Config & info)
     case BasicType::TENSOR:
         if (info.tensorType().is_dense()) {
             return std::make_shared<tensor::DenseTensorAttribute>(name, info);
-        } else if (vespalib::eval::EngineOrFactory::get().is_factory()) {
-            return std::make_shared<tensor::SerializedFastValueAttribute>(name, info);
         } else {
-            return std::make_shared<tensor::SerializedTensorAttribute>(name, info);
+            return std::make_shared<tensor::SerializedFastValueAttribute>(name, info);
         }
     case BasicType::REFERENCE:
         return std::make_shared<attribute::ReferenceAttribute>(name, info);
diff --git a/searchlib/src/vespa/searchlib/features/constant_tensor_executor.h b/searchlib/src/vespa/searchlib/features/constant_tensor_executor.h
index 835cd1a8e36..f95cbfa4726 100644
--- a/searchlib/src/vespa/searchlib/features/constant_tensor_executor.h
+++ b/searchlib/src/vespa/searchlib/features/constant_tensor_executor.h
@@ -6,7 +6,8 @@
 #include <vespa/eval/eval/tensor_spec.h>
 #include <vespa/eval/eval/value.h>
 #include <vespa/eval/eval/value_type.h>
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
+#include <vespa/eval/eval/value_codec.h>
 #include <vespa/vespalib/util/stash.h>
 
 namespace search::features {
@@ -31,9 +32,9 @@ public:
         return stash.create<ConstantTensorExecutor>(std::move(tensor));
     }
     static fef::FeatureExecutor &createEmpty(const vespalib::eval::ValueType &valueType, vespalib::Stash &stash) {
-        const auto engine = vespalib::eval::EngineOrFactory::get();
+        const auto &factory = vespalib::eval::FastValueBuilderFactory::get();
         auto spec = vespalib::eval::TensorSpec(valueType.to_spec());
-        return stash.create<ConstantTensorExecutor>(engine.from_spec(spec));
+        return stash.create<ConstantTensorExecutor>(vespalib::eval::value_from_spec(spec, factory));
     }
     static fef::FeatureExecutor &createEmpty(vespalib::Stash &stash) {
         return createEmpty(vespalib::eval::ValueType::double_type(), stash);
diff --git a/searchlib/src/vespa/searchlib/features/dotproductfeature.cpp b/searchlib/src/vespa/searchlib/features/dotproductfeature.cpp
index 83beee98634..06f0de631be 100644
--- a/searchlib/src/vespa/searchlib/features/dotproductfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/dotproductfeature.cpp
@@ -10,7 +10,8 @@
 #include <vespa/searchlib/attribute/floatbase.h>
 #include <vespa/searchlib/attribute/multinumericattribute.h>
 #include <vespa/searchlib/attribute/multienumattribute.h>
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
+#include <vespa/eval/eval/value_codec.h>
 #include <vespa/vespalib/objects/nbostream.h>
 #include <vespa/vespalib/util/stash.h>
 
@@ -19,7 +20,7 @@ LOG_SETUP(".features.dotproduct");
 
 using namespace search::attribute;
 using namespace search::fef;
-using vespalib::eval::EngineOrFactory;
+using vespalib::eval::FastValueBuilderFactory;
 using vespalib::eval::TypedCells;
 using vespalib::hwaccelrated::IAccelrated;
 
@@ -500,7 +501,7 @@ template <typename T>
 ArrayParam<T>::ArrayParam(vespalib::nbostream & stream) {
     using vespalib::typify_invoke;
     using vespalib::eval::TypifyCellType;
-    auto tensor = EngineOrFactory::get().decode(stream);
+    auto tensor = vespalib::eval::decode_value(stream, FastValueBuilderFactory::get());
     if (tensor->type().is_dense()) {
         TypedCells cells = tensor->cells();
         typify_invoke<1,TypifyCellType,CopyCellsToVector<T>>(cells.type, cells, values);
diff --git a/searchlib/src/vespa/searchlib/features/queryfeature.cpp b/searchlib/src/vespa/searchlib/features/queryfeature.cpp
index 9cded69d5de..c6196fcbc7f 100644
--- a/searchlib/src/vespa/searchlib/features/queryfeature.cpp
+++ b/searchlib/src/vespa/searchlib/features/queryfeature.cpp
@@ -12,6 +12,8 @@
 #include <vespa/searchlib/fef/feature_type.h>
 #include <vespa/vespalib/objects/nbostream.h>
 #include <vespa/eval/eval/value_type.h>
+#include <vespa/eval/eval/value_codec.h>
+#include <vespa/eval/eval/fast_value.h>
 #include <vespa/vespalib/locale/c.h>
 #include <cerrno>
 
@@ -119,7 +121,7 @@ createTensorExecutor(const IQueryEnvironment &env,
     if (prop.found() && !prop.get().empty()) {
         const vespalib::string &value = prop.get();
         vespalib::nbostream stream(value.data(), value.size());
-        auto tensor = vespalib::eval::EngineOrFactory::get().decode(stream);
+        auto tensor = vespalib::eval::decode_value(stream, vespalib::eval::FastValueBuilderFactory::get());
         if (!TensorDataType::isAssignableType(valueType, tensor->type())) {
             LOG(warning, "Query feature type is '%s' but other tensor type is '%s'",
                 valueType.to_spec().c_str(), tensor->type().to_spec().c_str());
diff --git a/searchlib/src/vespa/searchlib/queryeval/fake_requestcontext.h b/searchlib/src/vespa/searchlib/queryeval/fake_requestcontext.h
index b0cb076f65b..72520830d06 100644
--- a/searchlib/src/vespa/searchlib/queryeval/fake_requestcontext.h
+++ b/searchlib/src/vespa/searchlib/queryeval/fake_requestcontext.h
@@ -4,7 +4,8 @@
 
 #include <vespa/eval/eval/tensor_spec.h>
 #include <vespa/eval/eval/value.h>
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
+#include <vespa/eval/eval/value_codec.h>
 #include <vespa/searchcommon/attribute/iattributecontext.h>
 #include <vespa/searchlib/attribute/attributevector.h>
 #include <vespa/searchlib/attribute/attribute_blueprint_params.h>
@@ -34,7 +35,7 @@ public:
     }
     vespalib::eval::Value::UP get_query_tensor(const vespalib::string& tensor_name) const override {
         if (_query_tensor && (tensor_name == _query_tensor_name)) {
-            return vespalib::eval::EngineOrFactory::get().from_spec(*_query_tensor);
+            return vespalib::eval::value_from_spec(*_query_tensor, vespalib::eval::FastValueBuilderFactory::get());
         }
         return {};
     }
diff --git a/searchlib/src/vespa/searchlib/tensor/direct_tensor_attribute.cpp b/searchlib/src/vespa/searchlib/tensor/direct_tensor_attribute.cpp
index 62beb25be22..8cda62682d0 100644
--- a/searchlib/src/vespa/searchlib/tensor/direct_tensor_attribute.cpp
+++ b/searchlib/src/vespa/searchlib/tensor/direct_tensor_attribute.cpp
@@ -3,7 +3,7 @@
 #include "direct_tensor_attribute.h"
 #include "direct_tensor_saver.h"
 
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
 #include <vespa/eval/eval/value.h>
 #include <vespa/fastlib/io/bufferedfile.h>
 #include <vespa/searchlib/attribute/readerbase.h>
@@ -14,7 +14,7 @@
 #include "tensor_deserialize.h"
 #include "tensor_attribute.hpp"
 
-using vespalib::eval::EngineOrFactory;
+using vespalib::eval::FastValueBuilderFactory;
 
 namespace search::tensor {
 
@@ -73,7 +73,7 @@ DirectTensorAttribute::set_tensor(DocId lid, std::unique_ptr<vespalib::eval::Val
 void
 DirectTensorAttribute::setTensor(DocId lid, const vespalib::eval::Value &tensor)
 {
-    set_tensor(lid, EngineOrFactory::get().copy(tensor));
+    set_tensor(lid, FastValueBuilderFactory::get().copy(tensor));
 }
 
 std::unique_ptr<vespalib::eval::Value>
@@ -86,7 +86,7 @@ DirectTensorAttribute::getTensor(DocId docId) const
     if (ref.valid()) {
         auto ptr = _direct_store.get_tensor(ref);
         if (ptr) {
-            return EngineOrFactory::get().copy(*ptr);
+            return FastValueBuilderFactory::get().copy(*ptr);
         }
     }
     std::unique_ptr<vespalib::eval::Value> empty;
diff --git a/searchlib/src/vespa/searchlib/tensor/tensor_attribute.cpp b/searchlib/src/vespa/searchlib/tensor/tensor_attribute.cpp
index 96049375180..e0b21290284 100644
--- a/searchlib/src/vespa/searchlib/tensor/tensor_attribute.cpp
+++ b/searchlib/src/vespa/searchlib/tensor/tensor_attribute.cpp
@@ -7,13 +7,14 @@
 #include <vespa/vespalib/data/slime/cursor.h>
 #include <vespa/vespalib/data/slime/inserter.h>
 #include <vespa/vespalib/util/rcuvector.hpp>
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
+#include <vespa/eval/eval/value_codec.h>
 #include <vespa/eval/eval/tensor_spec.h>
 #include <vespa/eval/eval/value.h>
 
 using document::TensorDataType;
 using document::WrongTensorTypeException;
-using vespalib::eval::EngineOrFactory;
+using vespalib::eval::FastValueBuilderFactory;
 using vespalib::eval::TensorSpec;
 using vespalib::eval::Value;
 using vespalib::eval::ValueType;
@@ -31,9 +32,9 @@ constexpr size_t DEAD_SLACK = 0x10000u;
 Value::UP
 createEmptyTensor(const ValueType &type)
 {
-    auto engine = EngineOrFactory::get();
+    const auto &factory = FastValueBuilderFactory::get();
     TensorSpec empty_spec(type.to_spec());
-    return engine.from_spec(empty_spec);
+    return vespalib::eval::value_from_spec(empty_spec, factory);
 }
 
 vespalib::string makeWrongTensorTypeMsg(const ValueType &fieldTensorType, const ValueType &tensorType)
@@ -183,7 +184,7 @@ TensorAttribute::populate_state(vespalib::slime::Cursor& object) const
 vespalib::eval::Value::UP
 TensorAttribute::getEmptyTensor() const
 {
-    return EngineOrFactory::get().copy(*_emptyTensor);
+    return FastValueBuilderFactory::get().copy(*_emptyTensor);
 }
 
 vespalib::eval::TypedCells
diff --git a/searchlib/src/vespa/searchlib/tensor/tensor_deserialize.cpp b/searchlib/src/vespa/searchlib/tensor/tensor_deserialize.cpp
index 35be27bc03b..4fddd092451 100644
--- a/searchlib/src/vespa/searchlib/tensor/tensor_deserialize.cpp
+++ b/searchlib/src/vespa/searchlib/tensor/tensor_deserialize.cpp
@@ -2,18 +2,19 @@
 
 #include "tensor_deserialize.h"
 #include <vespa/document/util/serializableexceptions.h>
-#include <vespa/eval/eval/engine_or_factory.h>
+#include <vespa/eval/eval/fast_value.h>
+#include <vespa/eval/eval/value_codec.h>
 #include <vespa/eval/eval/value.h>
 
 using document::DeserializeException;
-using vespalib::eval::EngineOrFactory;
+using vespalib::eval::FastValueBuilderFactory;
 using vespalib::eval::Value;
 
 namespace search::tensor {
 
 std::unique_ptr<Value> deserialize_tensor(vespalib::nbostream &buffer)
 {
-    auto tensor = EngineOrFactory::get().decode(buffer);
+    auto tensor = vespalib::eval::decode_value(buffer, FastValueBuilderFactory::get());
     if (buffer.size() != 0) {
         throw DeserializeException("Leftover bytes deserializing tensor attribute value.", VESPA_STRLOC);
     }