[MetaSchedule][M4a] Schedule Rule: Multi-Level-Tiling

include/tvm/meta_schedule/schedule_rule.h

@@ -137,19 +137,17 @@ class ScheduleRule : public runtime::ObjectRef {
    * \param tile_binds For each level of tiles, which thread axis it is bound to. Recommended:
    * - NullOpt on CPU
    * - [blockIdx.x, vthread.x, threadIdx.x] on GPU
-   * \param use_tensor_core Whether to apply tensor core wmma intrinsic for the computation
    * \param max_innermost_factor The maximum size of the innermost factor. NullOpt means no limit
-   * \param vector_load_max_len The length of vector lane in vectorized cooperative fetching.
+   * \param vector_load_lens The length of vector lane in vectorized cooperative fetching.
    * NullOpt means disable vectorization
    * \param reuse_read Data reuse configuration for reading. NullOpt means no reuse.
    * \param reuse_write Data reuse configuration for writing. NullOpt means no reuse.
    * \return The schedule rule created
    */
   TVM_DLL static ScheduleRule MultiLevelTiling(String structure,                             //
                                                Optional<Array<String>> tile_binds,           //
-                                               bool use_tensor_core,                         //
                                                Optional<Integer> max_innermost_factor,       //
-                                               Optional<Integer> vector_load_max_len,        //
+                                               Optional<Array<Integer>> vector_load_lens,    //
                                                Optional<Map<String, ObjectRef>> reuse_read,  //
                                                Optional<Map<String, ObjectRef>> reuse_write);
   /*!

include/tvm/tir/stmt.h

@@ -1364,6 +1364,20 @@ constexpr const char* pragma_loop_partition_hint = "pragma_loop_partition_hint";
 /*! \brief Mark the tiling structure of blocks that are applied by rule Multi-Level-Tiling */
 constexpr const char* meta_schedule_tiling_structure = "meta_schedule.tiling_structure";
 
+/*!
+ * \brief Mark that the loop should be further skip and bound to environment threads to enable
+ * cooperative fetching.
+ */
+constexpr const char* meta_schedule_cooperative_fetch = "meta_schedule.cooperative_fetch";
+
+/*! \brief The allowed range of thread extent in thread bindings */
+constexpr const char* meta_schedule_thread_extent_low_inclusive =
+    "meta_schedule.thread_extent_low_inclusive";
+
+/*! \brief The allowed range of thread extent in thread bindings */
+constexpr const char* meta_schedule_thread_extent_high_inclusive =
+    "meta_schedule.thread_extent_high_inclusive";
+
 /*! \brief Mark the block whose producer needs to be applied by rule Random-Compute-Location */
 constexpr const char* meta_schedule_random_compute_producer =
     "meta_schedule.random_compute_producer";

python/tvm/meta_schedule/schedule_rule/__init__.py

@@ -19,6 +19,7 @@
 from .add_rfactor import AddRFactor
 from .auto_inline import AutoInline
 from .cross_thread_reduction import CrossThreadReduction
+from .multi_level_tiling import MultiLevelTiling, ReuseType
 from .parallel_vectorize_unroll import ParallelizeVectorizeUnroll
 from .random_compute_location import RandomComputeLocation
 from .schedule_rule import PyScheduleRule, ScheduleRule

python/tvm/meta_schedule/schedule_rule/multi_level_tiling.py

@@ -0,0 +1,84 @@
+# 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.
+"""Multi-level tiling with reuse."""
+from typing import Any, Dict, List, NamedTuple, Optional
+
+from tvm._ffi import register_object
+
+from .. import _ffi_api
+from .schedule_rule import ScheduleRule
+
+
+class ReuseType(NamedTuple):
+    """Reuse type."""
+
+    req: str
+    levels: List[int]
+    scope: str
+
+    def as_dict(self) -> Dict[str, Any]:
+        """Return the dict representation of the reuse type."""
+        return {
+            "req": self.req,
+            "levels": self.levels,
+            "scope": self.scope,
+        }
+
+
+@register_object("meta_schedule.MultiLevelTiling")
+class MultiLevelTiling(ScheduleRule):
+    """Multi-level tiling with reuse.
+
+    Parameters
+    ----------
+    structure : str
+        The tiling structure. Recommended:
+        - 'SSRSRS' on CPU
+        - 'SSSRRSRS' on GPU
+    tile_bind : Optional[List[str]]
+        For each level of tiles, which thread axis it is bound to. Recommended:
+        - None on CPU
+        - [blockIdx.x, vthread.x, threadIdx.x] on GPU
+    max_innermost_factor : Optional[int]
+        The maximum size of the innermost factor. None means no limit
+    vector_load_lens : Optional[List[int]]
+        The length of vector lane in vectorized cooperative fetching.
+        None means disable vectorization
+    reuse_read : Optional[ReuseType]
+        Data reuse configuration for reading. None means no reuse.
+    reuse_write : Optional[ReuseType]
+        Data reuse configuration for writing. None means no reuse.
+    """
+
+    def __init__(
+        self,
+        structure: str,
+        tile_binds: Optional[List[str]] = None,
+        max_innermost_factor: Optional[int] = None,
+        vector_load_lens: Optional[List[int]] = None,
+        reuse_read: Optional[ReuseType] = None,
+        reuse_write: Optional[ReuseType] = None,
+    ) -> None:
+        self.__init_handle_by_constructor__(
+            _ffi_api.ScheduleRuleMultiLevelTiling,  # type: ignore # pylint: disable=no-member
+            structure,
+            tile_binds,
+            max_innermost_factor,
+            vector_load_lens,
+            reuse_read.as_dict() if reuse_read is not None else None,
+            reuse_write.as_dict() if reuse_write is not None else None,
+        )

python/tvm/meta_schedule/testing/schedule_rule.py

@@ -19,8 +19,10 @@
     AddRFactor,
     AutoInline,
     CrossThreadReduction,
+    MultiLevelTiling,
     ParallelizeVectorizeUnroll,
     RandomComputeLocation,
+    ReuseType,
     ScheduleRule,
 )
 from tvm.target import Target
@@ -65,6 +67,41 @@ def cross_thread_reduction(target: Target) -> ScheduleRule:
     raise NotImplementedError(f"{target.kind.name} is not supported")
 
 
+def multi_level_tiling(target: Target) -> ScheduleRule:
+    """Default schedule rules for with multi-level tiling and reuse"""
+    if target.kind.name == "llvm":
+        return MultiLevelTiling(
+            structure="SSRSRS",
+            tile_binds=None,
+            max_innermost_factor=64,
+            vector_load_lens=None,
+            reuse_read=None,
+            reuse_write=ReuseType(
+                req="may",
+                levels=[1, 2],
+                scope="global",
+            ),
+        )
+    if target.kind.name == "cuda":
+        return MultiLevelTiling(
+            structure="SSSRRSRS",
+            tile_binds=["blockIdx.x", "vthread.x", "threadIdx.x"],
+            max_innermost_factor=64,
+            vector_load_lens=[1, 2, 3, 4],
+            reuse_read=ReuseType(
+                req="must",
+                levels=[4],
+                scope="shared",
+            ),
+            reuse_write=ReuseType(
+                req="must",
+                levels=[3],
+                scope="local",
+            ),
+        )
+    raise NotImplementedError(f"{target.kind.name} is not supported")
+
+
 def random_compute_location(target: Target) -> ScheduleRule:
     """Default schedule rules for with random-compute-location"""
     if target.kind.name == "llvm":