Arm backend: Create negative operator_support check unsupported u55 ops (#8682)

Since there will be more unsupported ops for u55 it makes more sense
to create a new negative check for ops which are always unsupported
on u55.

bitwise_support.py is removed with this patch as it's redundent with
the new negative check.

Signed-off-by: Sebastian Larsson <[email protected]>

Author: Sebastian-Larsson

backends/arm/operator_support/__init__.py

@@ -6,7 +6,6 @@
 # pyre-unsafe
 
 from . import (  # noqa
-    bitwise_support,
     convolution_support,
     pool_2d_support,
     reduce_sum_support,

backends/arm/operator_support/bitwise_support.py

@@ -11,13 +11,13 @@
 from typing import final, Optional, Sequence, Type
 
 import torch
-
 import torch.fx as fx
+
 from executorch.backends.arm._passes.arm_pass_utils import get_first_fake_tensor
 from executorch.backends.arm._passes.fuse_quantized_activation_pass import (
     FuseQuantizedActivationPass,
 )
-from executorch.backends.arm.tosa_specification import TosaSpecification
+from executorch.backends.arm.tosa_specification import Tosa_0_80, TosaSpecification
 from executorch.exir.dialects._ops import ops as exir_ops
 from torch.fx.passes.operator_support import any_chain, chain, OperatorSupportBase
 from torch.fx.passes.utils.source_matcher_utils import get_source_partitions
@@ -90,6 +90,7 @@ def tosa_support_factory(
     if not tosa_spec.support_float():
         negative_checks.append(NeedsDecompositionCheck())
         negative_checks.append(CheckProperQuantization())
+        negative_checks.append(EthosU55NotSupported(tosa_spec))
     return chain(
         any_chain(
             BaseTOSASupportList(),
@@ -111,6 +112,9 @@ def is_node_supported(
         supported = node.op == "call_function" and node.target in [
             exir_ops.edge.aten.abs.default,
             exir_ops.edge.aten.add.Tensor,
+            exir_ops.edge.aten.bitwise_and.Tensor,
+            exir_ops.edge.aten.bitwise_or.Tensor,
+            exir_ops.edge.aten.bitwise_xor.Tensor,
             exir_ops.edge.aten.expand_copy.default,
             exir_ops.edge.aten.cat.default,
             exir_ops.edge.aten.clamp.default,
@@ -170,6 +174,31 @@ def is_node_supported(
         return supported
 
 
+class EthosU55NotSupported(OperatorSupportBase):
+    """
+    Certain operators are not supported on U55. These are listed in `unsupported` in
+    is_node_supported().
+    """
+
+    def __init__(self, tosa_spec: TosaSpecification):
+        self.tosa_spec = tosa_spec
+
+    def is_node_supported(
+        self, submodules: typing.Mapping[str, torch.nn.Module], node: fx.Node
+    ) -> bool:
+        if isinstance(self.tosa_spec, Tosa_0_80) and self.tosa_spec.is_U55_subset:
+            unsupported_ops = [
+                exir_ops.edge.aten.bitwise_and.Tensor,
+                exir_ops.edge.aten.bitwise_or.Tensor,
+                exir_ops.edge.aten.bitwise_xor.Tensor,
+            ]
+
+            if node.target in unsupported_ops:
+                return False
+
+        return True
+
+
 class NeedsDecompositionCheck(OperatorSupportBase):
     """
     Targeted operators need to be decomposed prior to quantization in order to get a pair of q-dq-nodes surrounding