avoid torch.ops.load_library() calls

Summary:
Due to different buck root, code such as
```
torch.ops.load_library("//executorch/kernels/quantized:custom_ops_generated_lib")
```
is very hard to work both internally and in oss. Here I'm trying to leverage the `preload_deps` attribute in python_binary and python_unittest, and remove `torch.ops.load_library` calls. This should unblock these tests/binaries to be running in OSS.

Reviewed By: cccclai

Differential Revision: D48018133

fbshipit-source-id: 06dcf01a611e5b8877a71ebded5f9753db22a55f

Author: larryliu0820

backends/test/TARGETS

@@ -86,6 +86,10 @@ python_unittest(
     srcs = [
         "test_backends.py",
     ],
+    preload_deps = [
+        "//executorch/kernels/portable:custom_ops_generated_lib",
+        "//executorch/kernels/quantized:custom_ops_generated_lib",
+    ],
     deps = [
         ":backend_with_compiler_demo",
         ":hta_partitioner_demo",
@@ -105,8 +109,6 @@ python_unittest(
         "//executorch/exir/dialects:lib",
         "//executorch/extension/pybindings:portable",  # @manual
         "//executorch/extension/pytree:pylib",
-        "//executorch/kernels/portable:custom_ops_generated_lib",
-        "//executorch/kernels/quantized:custom_ops_generated_lib",
         "//executorch/runtime/executor/test:test_backend_compiler_lib",
     ],
 )
@@ -116,6 +118,10 @@ python_unittest(
     srcs = [
         "test_backends_lifted.py",
     ],
+    preload_deps = [
+        "//executorch/kernels/portable:custom_ops_generated_lib",
+        "//executorch/kernels/quantized:custom_ops_generated_lib",
+    ],
     deps = [
         ":backend_with_compiler_demo",
         ":hta_partitioner_demo",
@@ -135,8 +141,6 @@ python_unittest(
         "//executorch/exir/dialects:lib",
         "//executorch/extension/pybindings:portable",  # @manual
         "//executorch/extension/pytree:pylib",
-        "//executorch/kernels/portable:custom_ops_generated_lib",
-        "//executorch/kernels/quantized:custom_ops_generated_lib",
         "//executorch/runtime/executor/test:test_backend_compiler_lib",
     ],
 )
@@ -163,6 +167,10 @@ python_unittest(
     srcs = [
         "test_backends_nested.py",
     ],
+    preload_deps = [
+        "//executorch/kernels/portable:custom_ops_generated_lib",
+        "//executorch/kernels/quantized:custom_ops_generated_lib",
+    ],
     deps = [
         ":op_partitioner_demo",
         "//caffe2:torch",
@@ -176,8 +184,6 @@ python_unittest(
         "//executorch/exir:graph_module",
         "//executorch/exir:lib",
         "//executorch/exir:lowered_backend_module",
-        "//executorch/kernels/portable:custom_ops_generated_lib",
-        "//executorch/kernels/quantized:custom_ops_generated_lib",
         "//executorch/runtime/executor/test:test_backend_compiler_lib",
     ],
 )

backends/test/test_backends.py

@@ -62,9 +62,6 @@
 from torch.testing import FileCheck
 
 
-torch.ops.load_library("//executorch/kernels/portable:custom_ops_generated_lib")
-
-
 def vary_segments(test_method):
     """A decorator that calls the test method with `extract_segments` set to
     True and False.

backends/test/test_backends_lifted.py

@@ -65,9 +65,6 @@
 from torch.testing import FileCheck
 
 
-torch.ops.load_library("//executorch/kernels/portable:custom_ops_generated_lib")
-
-
 def get_testing_capture_config():
     return exir.CaptureConfig(pt2_mode=True, enable_aot=True, _unlift=False)
 

backends/vulkan/test/TARGETS

@@ -8,6 +8,7 @@ python_unittest(
     preload_deps = [
         "fbsource//third-party/swiftshader/lib/linux-x64:libvk_swiftshader_fbcode",
         "//executorch/backends/vulkan:vulkan_backend_lib",
+        "//executorch/kernels/portable:custom_ops_generated_lib",
     ],
     deps = [
         "//caffe2:torch",
@@ -17,7 +18,6 @@ python_unittest(
         "//executorch/exir/serialize:lib",
         "//executorch/extension/pybindings:portable",  # @manual
         "//executorch/extension/pytree:pylib",
-        "//executorch/kernels/portable:custom_ops_generated_lib",
         "//executorch/runtime/executor/test:test_backend_compiler_lib",
     ],
 )

exir/tests/TARGETS

@@ -157,11 +157,13 @@ python_unittest(
     srcs = [
         "test_op_convert.py",
     ],
-    deps = [
+    preload_deps = [
+        "//executorch/kernels/portable:custom_ops_generated_lib",
         ":test_lib",  # @manual
+    ],
+    deps = [
         "//caffe2:torch",
         "//executorch/exir/operator:convert",
-        "//executorch/kernels/portable:custom_ops_generated_lib",
     ],
 )
 
@@ -170,6 +172,9 @@ python_unittest(
     srcs = [
         "test_memory_planning.py",
     ],
+    preload_deps = [
+        "//executorch/kernels/portable:custom_ops_generated_lib",
+    ],
     deps = [
         ":asr_joiner",
         "//caffe2:torch",
@@ -181,7 +186,6 @@ python_unittest(
         "//executorch/exir:print_program",
         "//executorch/exir:schema",
         "//executorch/exir/passes:lib",
-        "//executorch/kernels/portable:custom_ops_generated_lib",
     ],
 )
 
@@ -316,13 +320,15 @@ python_unittest(
     srcs = [
         "test_quant_fusion_pass.py",
     ],
+    preload_deps = [
+        "//executorch/kernels/quantized:custom_ops_generated_lib",
+    ],
     deps = [
         ":lib",
         "//caffe2:torch",
         "//executorch/exir:lib",
         "//executorch/exir:tracer",
         "//executorch/exir/passes:quant_fusion_pass",
-        "//executorch/kernels/quantized:custom_ops_generated_lib",
     ],
 )
 
@@ -331,13 +337,15 @@ python_unittest(
     srcs = [
         "test_quantization.py",
     ],
+    preload_deps = [
+        "//executorch/kernels/quantized:custom_ops_generated_lib",
+    ],
     deps = [
         "//caffe2:torch",
         "//executorch/exir:lib",
         "//executorch/exir:tracer",
         "//executorch/exir/passes:quant_fusion_pass",
         "//executorch/exir/passes:spec_prop_pass",
-        "//executorch/kernels/quantized:custom_ops_generated_lib",
         "//pytorch/vision:torchvision",
     ],
 )

exir/tests/test_op_convert.py

@@ -13,9 +13,6 @@
 from executorch.exir.operator.convert import to_out_variant
 from torch._ops import OpOverload
 
-torch.ops.load_library("//executorch/exir/tests:test_lib")
-torch.ops.load_library("//executorch/kernels/portable:custom_ops_generated_lib")
-
 
 class TestToOutVariant(unittest.TestCase):
     def test_already_out_var(self) -> None:

exir/tests/test_quant_fusion_pass.py

@@ -31,9 +31,6 @@
 
 from torch.testing import FileCheck
 
-# load executorch out variant ops
-torch.ops.load_library("//executorch/kernels/quantized:custom_ops_generated_lib")
-
 
 class TestQuantFusionPass(unittest.TestCase):
     @classmethod