[MetaSchedule] Union and OrderedUnion Database

Following up apache#12520 and apache#12626, this PR introduces two database classes:
`UnionDatabase` and `OrderedUnionDatabase`, both of which allow users to
organically compose multiple databases together, so that the high-level
IR (Relay, Relax) could select the best tuning records according to
running time or a preferred order given by users.

To each query, `UnionDatabase` returns the best record among all the
databases given; Instead, `OrderedUnionDatabase` returns he record from
the first database that responds to the query.

Used together, users may specify complicated dispatching patterns like
below:

```python
def schedule_fn(sch: tir.Schedule) -> bool:
  if "nn_conv2d" in sch.mod.attrs["task_name"]:
    if some_other_tir_conditions(sch.mod):
      handcrafted_scheduling(sch)
      return True
  return False

with ms.database.OrderedUnionDatabase(
  ms.database.ScheduleFn(schedule_fn),  # hand-override some scheduling
  ms.database.Union(                    # existing databases
    db_for_matmul,
    db_for_conv2d,
    db_for_softmax,
  )
  libtorch_database,                    # fallback to libtorch
):
  lib = relay.build(...)
```

include/tvm/meta_schedule/database.h

@@ -357,6 +357,22 @@ class Database : public runtime::ObjectRef {
    */
   TVM_DLL static Database JSONDatabase(String path_workload, String path_tuning_record,
                                        bool allow_missing);
+  /*!
+   * \brief A database composed of multiple databases, allowing users to guide IR rewriting using
+   * combined knowledge of those databases. To each query, it returns the best record among all the
+   * databases given.
+   * \param databases The list of databases to be combined.
+   * \return The combined database.
+   */
+  TVM_DLL static Database UnionDatabase(Array<Database, void> databases);
+  /*!
+   * \brief A database composed of multiple databases, allowing users to guide IR rewriting using
+   * combined knowledge of those databases. To each query, it returns the record from the first
+   * database that responds to the query.
+   * \param databases The database to be subsetted.
+   * \return The subsetted database.
+   */
+  TVM_DLL static Database OrderedUnionDatabase(Array<Database, void> databases);
   /*!
    * \brief Create a database with customized methods on the python-side.
    * \param f_has_workload The packed function of `HasWorkload`.

python/tvm/meta_schedule/database/__init__.py

@@ -21,4 +21,6 @@
 from .database import Database, PyDatabase, TuningRecord, Workload
 from .json_database import JSONDatabase
 from .memory_database import MemoryDatabase
+from .ordered_union_database import OrderedUnionDatabase
 from .schedule_fn_database import ScheduleFnDatabase
+from .union_database import UnionDatabase

python/tvm/meta_schedule/database/ordered_union_database.py

@@ -0,0 +1,60 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+"""A database consists of multiple databases."""
+from tvm._ffi import register_object
+
+from .. import _ffi_api
+from .database import Database
+
+
+@register_object("meta_schedule.OrderedUnionDatabase")
+class OrderedUnionDatabase(Database):
+    """A database composed of multiple databases, allowing users to guide IR rewriting using
+    combined knowledge of those databases. To each query, it returns the record from the first
+    database that responds to the query.
+
+    Examples
+    --------
+    An example of using the union:
+
+    .. code-block:: python
+    def schedule_conv2d(sch: tir.Schedule) -> bool:
+        if "nn_conv2d" in sch.mod.attrs["task_name"]:
+            handcrafted_scheduling(sch)
+            return True
+        return False
+
+    with ms.database.OrderedUnionDatabase(
+        ScheduleFnDatabase(schedule_conv2d),   # override schedule for conv2d
+        existing_database,                     # use existing database
+        mocked_libtorch_database,              # use mocked libtorch database for fallback
+    ):
+        lib = relay.build(...)
+    """
+
+    def __init__(self, *databases: Database) -> None:
+        """Construct a merged database from multiple databases.
+
+        Parameters
+        ----------
+        *databases : Database
+            The list of databases to combine.
+        """
+        self.__init_handle_by_constructor__(
+            _ffi_api.DatabaseOrderedUnionDatabase,  # type: ignore # pylint: disable=no-member
+            databases,
+        )

python/tvm/meta_schedule/database/union_database.py

@@ -0,0 +1,54 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+"""A database consists of multiple databases."""
+from tvm._ffi import register_object
+
+from .. import _ffi_api
+from .database import Database
+
+
+@register_object("meta_schedule.UnionDatabase")
+class UnionDatabase(Database):
+    """A database composed of multiple databases, allowing users to guide IR rewriting using
+    combined knowledge of those databases. To each query, it returns the best record among all the
+    databases given.
+
+    Examples
+    --------
+    An example of using the union:
+
+    .. code-block:: python
+    with ms.database.UnionDatabase(
+        db_for_matmul,
+        db_for_conv2d,
+        db_for_softmax,
+    ):
+        lib = relay.build(...)
+    """
+
+    def __init__(self, *databases: Database) -> None:
+        """Construct a merged database from multiple databases.
+
+        Parameters
+        ----------
+        *databases : Database
+            The list of databases to combine.
+        """
+        self.__init_handle_by_constructor__(
+            _ffi_api.DatabaseUnionDatabase,  # type: ignore # pylint: disable=no-member
+            databases,
+        )

src/meta_schedule/database/json_database.cc

@@ -25,28 +25,6 @@
 namespace tvm {
 namespace meta_schedule {
 
-/*! \brief The struct defining comparison function of sorting by mean run seconds. */
-struct SortTuningRecordByMeanRunSecs {
-  static const constexpr double kMaxMeanTime = 1e10;
-
-  static double Mean(const Array<FloatImm>& a) {
-    if (a.empty()) {
-      return kMaxMeanTime;
-    }
-    double sum = 0.0;
-    for (const FloatImm& i : a) {
-      sum += i->value;
-    }
-    return sum / a.size();
-  }
-
-  bool operator()(const TuningRecord& a, const TuningRecord& b) const {
-    double a_time = Mean(a->run_secs.value_or({}));
-    double b_time = Mean(b->run_secs.value_or({}));
-    return a_time < b_time;
-  }
-};
-
 /*!
  * \brief Read lines from a json file.
  * \param path The path to the json file.

src/meta_schedule/database/ordered_union_database.cc

@@ -0,0 +1,86 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+#include "../utils.h"
+
+namespace tvm {
+namespace meta_schedule {
+
+class OrderedUnionDatabaseNode : public DatabaseNode {
+ public:
+  Array<Database> databases;
+
+  void VisitAttrs(AttrVisitor* v) { v->Visit("databases", &databases); }
+
+  static constexpr const char* _type_key = "meta_schedule.OrderedUnionDatabase";
+  TVM_DECLARE_FINAL_OBJECT_INFO(OrderedUnionDatabaseNode, DatabaseNode);
+
+ public:
+  Optional<TuningRecord> QueryTuningRecord(const IRModule& mod, const Target& target,
+                                           const String& task_name) final {
+    for (const Database& db : databases) {
+      if (Optional<TuningRecord> record = db->QueryTuningRecord(mod, target, task_name)) {
+        return record;
+      }
+    }
+    return NullOpt;
+  }
+
+  bool HasWorkload(const IRModule& mod) final {
+    LOG(FATAL) << "NotImplementedError: OrderedUnionDatabase.HasWorkload";
+    throw;
+  }
+
+  Workload CommitWorkload(const IRModule& mod) final {
+    LOG(FATAL) << "NotImplementedError: OrderedUnionDatabase.CommitWorkload";
+    throw;
+  }
+
+  void CommitTuningRecord(const TuningRecord& record) final {
+    LOG(FATAL) << "NotImplementedError: OrderedUnionDatabase.CommitTuningRecord";
+    throw;
+  }
+
+  Array<TuningRecord> GetTopK(const Workload& workload, int top_k) final {
+    LOG(FATAL) << "NotImplementedError: OrderedUnionDatabase.GetTopK";
+    throw;
+  }
+
+  Array<TuningRecord> GetAllTuningRecords() final {
+    LOG(FATAL) << "NotImplementedError: OrderedUnionDatabase.GetAllTuningRecords";
+    throw;
+  }
+
+  int64_t Size() final {
+    LOG(FATAL) << "NotImplementedError: OrderedUnionDatabase.size";
+    throw;
+  }
+};
+
+Database Database::OrderedUnionDatabase(Array<Database> databases) {
+  ObjectPtr<OrderedUnionDatabaseNode> n = make_object<OrderedUnionDatabaseNode>();
+  n->databases = std::move(databases);
+  return Database(n);
+}
+
+TVM_REGISTER_NODE_TYPE(OrderedUnionDatabaseNode);
+TVM_REGISTER_GLOBAL("meta_schedule.DatabaseOrderedUnionDatabase")
+    .set_body_typed(Database::OrderedUnionDatabase);
+
+}  // namespace meta_schedule
+}  // namespace tvm

src/meta_schedule/database/union_database.cc

@@ -0,0 +1,88 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+#include "../utils.h"
+
+namespace tvm {
+namespace meta_schedule {
+
+class UnionDatabaseNode : public DatabaseNode {
+ public:
+  Array<Database> databases;
+
+  void VisitAttrs(AttrVisitor* v) { v->Visit("databases", &databases); }
+
+  static constexpr const char* _type_key = "meta_schedule.UnionDatabase";
+  TVM_DECLARE_FINAL_OBJECT_INFO(UnionDatabaseNode, DatabaseNode);
+
+ public:
+  Optional<TuningRecord> QueryTuningRecord(const IRModule& mod, const Target& target,
+                                           const String& task_name) final {
+    std::vector<TuningRecord> results;
+    results.reserve(databases.size());
+    for (const Database& db : databases) {
+      if (Optional<TuningRecord> record = db->QueryTuningRecord(mod, target, task_name)) {
+        results.push_back(record.value());
+      }
+    }
+    std::stable_sort(results.begin(), results.end(), SortTuningRecordByMeanRunSecs());
+    return results.empty() ? Optional<TuningRecord>(NullOpt) : results[0];
+  }
+
+  bool HasWorkload(const IRModule& mod) final {
+    LOG(FATAL) << "NotImplementedError: UnionDatabase.HasWorkload";
+    throw;
+  }
+
+  Workload CommitWorkload(const IRModule& mod) final {
+    LOG(FATAL) << "NotImplementedError: UnionDatabase.CommitWorkload";
+    throw;
+  }
+
+  void CommitTuningRecord(const TuningRecord& record) final {
+    LOG(FATAL) << "NotImplementedError: UnionDatabase.CommitTuningRecord";
+    throw;
+  }
+
+  Array<TuningRecord> GetTopK(const Workload& workload, int top_k) final {
+    LOG(FATAL) << "NotImplementedError: UnionDatabase.GetTopK";
+    throw;
+  }
+
+  Array<TuningRecord> GetAllTuningRecords() final {
+    LOG(FATAL) << "NotImplementedError: UnionDatabase.GetAllTuningRecords";
+    throw;
+  }
+
+  int64_t Size() final {
+    LOG(FATAL) << "NotImplementedError: UnionDatabase.size";
+    throw;
+  }
+};
+
+Database Database::UnionDatabase(Array<Database> databases) {
+  ObjectPtr<UnionDatabaseNode> n = make_object<UnionDatabaseNode>();
+  n->databases = std::move(databases);
+  return Database(n);
+}
+
+TVM_REGISTER_NODE_TYPE(UnionDatabaseNode);
+TVM_REGISTER_GLOBAL("meta_schedule.DatabaseUnionDatabase").set_body_typed(Database::UnionDatabase);
+
+}  // namespace meta_schedule
+}  // namespace tvm

src/meta_schedule/utils.h

@@ -404,6 +404,28 @@ inline Array<Integer> AsIntArray(const ObjectRef& obj) {
   return results;
 }
 
+/*! \brief The struct defining comparison function of sorting by mean run seconds. */
+struct SortTuningRecordByMeanRunSecs {
+  static const constexpr double kMaxMeanTime = 1e10;
+
+  static double Mean(const Array<FloatImm>& a) {
+    if (a.empty()) {
+      return kMaxMeanTime;
+    }
+    double sum = 0.0;
+    for (const FloatImm& i : a) {
+      sum += i->value;
+    }
+    return sum / a.size();
+  }
+
+  bool operator()(const TuningRecord& a, const TuningRecord& b) const {
+    double a_time = Mean(a->run_secs.value_or({}));
+    double b_time = Mean(b->run_secs.value_or({}));
+    return a_time < b_time;
+  }
+};
+
 }  // namespace meta_schedule
 }  // namespace tvm
 

tests/python/unittest/test_link_params.py

@@ -412,15 +412,10 @@ def schedule_fn(sch):
             return True
         return False
 
-    link_params = True
-
     with StringIO() as stderr_buf, redirect_stderr(stderr_buf):
         with ms.database.ScheduleFnDatabase(schedule_fn), tvm.transform.PassContext(
             opt_level=3,
-            config={
-                "relay.backend.use_meta_schedule": True,
-                "relay.FuseOps.link_params": link_params,
-            },
+            config={"relay.backend.use_meta_schedule": True},
         ):
             executor = Executor("graph", {"link-params": link_params})
             lib = relay.build(relay_mod, target=target, executor=executor)