[ETHOSN] Connect existing arm_cpu schedule to relay strategy for conc…

…atenate

NPU used generic implementation for concatenate
before cpu schedules were made the default fallback
schedules. This leads to performance degradation
as this blocks fusion with nearby ops. This commit
adds Relay op strategy for arm_cpu implementation
which makes it use arm_cpu schedule before cpu one.
Reference: #13775

Co-authored-by: Luke Hutton <luke.hutton@arm.com>

python/tvm/relay/op/strategy/arm_cpu.py

@@ -46,11 +46,17 @@ def schedule_injective_arm_cpu(_, outs, target):
         return topi.arm_cpu.schedule_injective(outs)
 
 
-@schedule_concatenate.register("arm_cpu")
-def schedule_concatenate_arm_cpu(_, outs, target):
-    """schedule concatenate for arm cpu"""
-    with target:
-        return topi.arm_cpu.schedule_concatenate(outs)
+@concatenate_strategy.register(["arm_cpu"])
+def concatenate_strategy_arm_cpu(attrs, inputs, out_type, target):
+    """concatenate arm_cpu strategy"""
+    strategy = _op.OpStrategy()
+
+    strategy.add_implementation(
+        wrap_compute_concat(topi.concatenate),
+        wrap_topi_schedule(topi.arm_cpu.schedule_concatenate),
+        name="concatenate.arm_cpu",
+    )
+    return strategy
 
 
 @schedule_pool.register(["arm_cpu"])

tests/python/relay/test_select_implementation.py

@@ -0,0 +1,56 @@
+# 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.
+
+""" Tests strategy selection for Relay ops """
+import pytest
+import tvm
+from tvm import relay
+from tvm import te
+from tvm.relay.testing import run_infer_type
+import tvm.testing
+
+
+@pytest.mark.parametrize(
+    "target, expected_implementation",
+    [("llvm", "concatenate.cpu"), ("llvm -device=arm_cpu", "concatenate.arm_cpu")],
+)
+def test_concatenate(target, expected_implementation):
+    target = tvm.target.Target(target)
+
+    shape = (1, 1, 1, 3)
+    dtype = "float32"
+    axis = 1
+    inputs = []
+    inputs.append(relay.var("var0", shape=shape, dtype=dtype))
+    inputs.append(relay.var("var1", shape=shape, dtype=dtype))
+    input_tuple = relay.Tuple(inputs)
+    out = relay.op.concatenate(input_tuple, axis)
+    out = run_infer_type(out)
+
+    impl, xx = relay.backend.te_compiler.select_implementation(
+        relay.op.get("concatenate"),
+        out.attrs,
+        [te.placeholder(shape)],
+        out.checked_type,
+        target,
+        use_autotvm=False,
+    )
+    assert impl.name == expected_implementation
+
+
+if __name__ == "__main__":
+    tvm.testing.main()