Cortex-M backend: Add CortexMPassManager (#14986)

Signed-off-by: Adrian Lundell <[email protected]>

Author: AdrianLundell

backends/cortex_m/passes/__init__.py

@@ -0,0 +1,9 @@
+# Copyright 2025 Arm Limited and/or its affiliates.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+from .quantized_linear_fusion_pass import QuantizedLinearFusionPass  # noqa
+from .quantized_op_fusion_pass import QuantizedOpFusionPass  # noqa
+from .replace_quant_nodes_pass import ReplaceQuantNodesPass  # noqa
+from .cortex_m_pass_manager import CortexMPassManager  # noqa  # usort: skip

backends/cortex_m/passes/cortex_m_pass_manager.py

@@ -0,0 +1,25 @@
+# Copyright 2025 Arm Limited and/or its affiliates.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+
+from executorch.backends.cortex_m.passes import (
+    QuantizedLinearFusionPass,
+    QuantizedOpFusionPass,
+    ReplaceQuantNodesPass,
+)
+from executorch.backends.xnnpack._passes import XNNPACKPassManager
+from executorch.exir.pass_base import ExportPass
+
+
+class CortexMPassManager(XNNPACKPassManager):
+
+    pass_list: list[ExportPass] = [
+        ReplaceQuantNodesPass,
+        QuantizedOpFusionPass,
+        QuantizedLinearFusionPass,
+    ]
+
+    def __init__(self, exported_program, passes=None):
+        super().__init__(exported_program, passes or self.pass_list)

backends/cortex_m/test/tester.py

@@ -10,16 +10,7 @@
 import torch
 from executorch.backends.arm.test.common import get_u55_compile_spec
 from executorch.backends.arm.test.tester.arm_tester import Serialize
-from executorch.backends.cortex_m.passes.quantized_linear_fusion_pass import (
-    QuantizedLinearFusionPass,
-)
-from executorch.backends.cortex_m.passes.quantized_op_fusion_pass import (
-    QuantizedOpFusionPass,
-)
-
-from executorch.backends.cortex_m.passes.replace_quant_nodes_pass import (
-    ReplaceQuantNodesPass,
-)
+from executorch.backends.cortex_m.passes.cortex_m_pass_manager import CortexMPassManager
 from executorch.backends.test.harness import Tester as TesterBase
 from executorch.backends.test.harness.stages import (
     Export,
@@ -29,7 +20,6 @@
     ToEdgeTransformAndLower,
     ToExecutorch,
 )
-from executorch.backends.xnnpack._passes import XNNPACKPassManager
 
 from executorch.backends.xnnpack.quantizer.xnnpack_quantizer import (
     get_symmetric_quantization_config,
@@ -47,12 +37,8 @@ def __init__(self):
 class CortexMRunPasses(RunPasses):
     def __init__(self):
         super().__init__(
-            XNNPACKPassManager,
-            pass_list=[
-                ReplaceQuantNodesPass,
-                QuantizedLinearFusionPass,
-                QuantizedOpFusionPass,
-            ],
+            CortexMPassManager,
+            CortexMPassManager.pass_list,
         )