Milestone2.1: Partition to_dim_order_copy op in XNN delegate (#11286)

### Summary
Add to_dim_order_copy op to the partitioner in XNN delegate and delegate dim order conversions (to_dim_order_copy op) manually initiated by user using .to(memory_format=<format>). By incorporating this operation into the partitioner, we can optimize the processing of dimension order conversions, leading to faster execution times and enhanced overall performance.

### Test plan
I added a test that manually invoked the .to(memory_format=<format>) method and confirmed that it was partitioned. I did this by checking that the graph after lowering made a delegate call for the to_copy op instead of calling the default op.

Author: leafs1

backends/xnnpack/_passes/channels_last_tagged_reshape_pass.py

@@ -395,6 +395,11 @@ def call(self, graph_module: torch.fx.GraphModule):  # noqa: C901
                 # The node requires nchw inputs
                 for input_node in node.all_input_nodes:
                     self.input_to_nchw(graph_module, input_node, node)
+            elif node.target == exir_ops.edge.aten._to_copy.default:
+                if node.kwargs["memory_format"] == torch.channels_last:
+                    self.mark_as_nhwc_node(node)
+                else:
+                    self.mark_as_nchw_node(node)
             else:
                 # The node can have inputs in any format (but all must be the
                 # same format)

backends/xnnpack/partition/config/__init__.py

@@ -50,6 +50,7 @@
     SquareRootConfig,
     SubConfig,
     TanhConfig,
+    ToDimOrderCopyConfig,
     UpsampleBilinear2dConfig,
 )
 from executorch.backends.xnnpack.partition.config.node_configs import (
@@ -102,6 +103,8 @@
     ReciprocalSquareRootConfig,
     ReLUConfig,
     TanhConfig,
+    ToDimOrderCopyConfig,
+    # SDPAConfig, TODO: D60553559: preserving SDPA for fairseq fails
     SigmoidConfig,
     SliceCopyConfig,
     SoftmaxConfig,

backends/xnnpack/partition/config/generic_node_configs.py

@@ -397,6 +397,35 @@ def supported_precision_types(self) -> List[ConfigPrecisionType]:
         return [ConfigPrecisionType.FP32]
 
 
+class ToDimOrderCopyConfig(GenericNodePartitionerConfig):
+    target_name = "_to_dim_order_copy.default"
+
+    def check_constraints(self, node: torch.fx.Node, ep: ExportedProgram) -> bool:
+        """
+        Only support dim order conversion partitioning, not DType conversions
+        """
+        if not self.check_common_constraints(node, ep):
+            return False
+
+        # Get input node and compare dtypes
+        input_node = get_input_node(node, 0)
+        input_dtype = input_node.meta["val"].dtype
+        output_dtype = node.meta["val"].dtype
+
+        # Return False if doing dtype conversion
+        if input_dtype != output_dtype:
+            why(
+                node,
+                reason=f"dtype conversion from {input_dtype} to {output_dtype} is not supported",
+            )
+            return False
+
+        return True
+
+    def supported_precision_types(self) -> List[ConfigPrecisionType]:
+        return [ConfigPrecisionType.FP32]
+
+
 class MeanDimConfig(GenericNodePartitionerConfig):
     target_name = "mean.dim"
 

backends/xnnpack/test/ops/test_to_copy.py

@@ -0,0 +1,85 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree.
+
+import unittest
+
+import torch
+
+from executorch.backends.xnnpack.test.tester import Tester
+
+
+class TestChannelsLastTaggedReshapePass(unittest.TestCase):
+    def setUp(self):
+        torch._dynamo.reset()
+
+    def run_tester(self, module, inputs):
+        tester = Tester(
+            module.eval(),
+            inputs,
+        )
+        tester.export().to_edge_transform_and_lower().to_executorch().serialize().run_method_and_compare_outputs()
+
+    class ChannelLastBeforeLinear(torch.nn.Module):
+        def __init__(self):
+            super().__init__()
+            self.linear = torch.nn.Linear(3, 3)
+
+        def forward(self, x):
+            y = x.to(memory_format=torch.channels_last)
+            return self.linear(y)
+
+    ChannelLastBeforeLinearModule = ChannelLastBeforeLinear()
+
+    def test_channel_last_before_linear(self):
+        self.run_tester(self.ChannelLastBeforeLinearModule, (torch.randn(1, 3, 3, 3),))
+
+    class ContiguousBeforeConv(torch.nn.Module):
+        def __init__(self):
+            super().__init__()
+            self.conv = torch.nn.Conv2d(3, 3, 3)
+
+        def forward(self, x):
+            y = x.to(memory_format=torch.contiguous_format)
+            return self.conv(y)
+
+    ContiguousBeforeConvModule = ContiguousBeforeConv()
+
+    def test_contiguous_before_conv(self):
+        self.run_tester(self.ContiguousBeforeConvModule, (torch.randn(1, 3, 6, 6),))
+
+    class DtypeAndMemoryFormatConversion(torch.nn.Module):
+        def __init__(self):
+            super().__init__()
+            self.conv = torch.nn.Conv2d(3, 3, 3)
+
+        def forward(self, x):
+            y = x.to(torch.float, memory_format=torch.channels_last)
+            return self.conv(y)
+
+    DtypeAndMemoryFormatConversionModule = DtypeAndMemoryFormatConversion()
+
+    def test_dtype_and_memory_format_conversion(self):
+        self.run_tester(
+            self.DtypeAndMemoryFormatConversionModule,
+            (torch.randint(0, 10, (1, 3, 6, 6), dtype=torch.int32),),
+        )
+
+    class DtypeAndMemoryFormatWithLinear(torch.nn.Module):
+        def __init__(self):
+            super().__init__()
+            self.linear = torch.nn.Linear(3, 3)
+
+        def forward(self, x):
+            y = x.to(torch.float, memory_format=torch.channels_last)
+            return self.linear(y)
+
+    DtypeAndMemoryFormatWithLinearModule = DtypeAndMemoryFormatWithLinear()
+
+    def test_dtype_and_memory_format_with_linear(self):
+        self.run_tester(
+            self.DtypeAndMemoryFormatWithLinearModule,
+            (torch.randint(0, 10, (1, 3, 3, 3), dtype=torch.int16),),
+        )

backends/xnnpack/test/passes/test_channels_last_tagged_reshape.py

@@ -173,6 +173,23 @@ def test_fp32_channels_last_tagged_reshape_pass(self):
                 .run_method_and_compare_outputs()
             )
 
+    class LinearConvDimSwap(torch.nn.Module):
+        def __init__(self):
+            super().__init__()
+            self.conv1 = torch.nn.Conv2d(3, 3, 3)
+            self.linear1 = torch.nn.Linear(4, 3)
+
+        def forward(self, x):
+            y = self.linear1(x)
+            y = y.to(memory_format=torch.channels_last)
+            y = y.to(memory_format=torch.contiguous_format)
+            return self.conv1(y)
+
+    LinearConvDimSwapModule = LinearConvDimSwap()
+
+    def test_conv_linear_dim_order_swap_partitioner(self):
+        self.run_tester(self.LinearConvDimSwapModule, (torch.randn(1, 3, 6, 4),))
+
     def test_qs8_channels_last_tagged_reshape_pass(self):
         for module, num_reshape in self.modules.items():
             (