Add `ReadOnly` trait to `copy.to_vtensor` (#2179)

Before inlining a global slot, the users of the global slot are
checked to see if they are `ReadOnly` or `MemoryEffectFree` to make
sure that the global slot is not being mutated. Because the op
`copy.to_vtensor` currently does not have the `ReadOnly` trait, if a
global slot is passed to `copy.to_vtensor`, the pass
`InlineGlobalSlots` will fail.

The op `copy.to_vtensor` is `ReadOnly`, since it does not modify the
contents of the input tensor; it simply makes a new copy. This commit
adds the trait as well as an e2e test that generates the case of a
global slot being passed to a `copy.to_vtensor`.

e2e_testing/main.py

@@ -32,6 +32,7 @@ from .xfail_sets import (
     STABLEHLO_PASS_SET,
     TOSA_PASS_SET,
     LTC_XFAIL_SET,
+    LTC_CRASHING_SET,
     TORCHDYNAMO_XFAIL_SET,
     TORCHDYNAMO_CRASHING_SET
 )
@@ -108,7 +109,7 @@ def main():
     elif args.config == "lazy_tensor_core":
         config = LazyTensorCoreTestConfig()
         xfail_set = LTC_XFAIL_SET
-        crashing_set = set()
+        crashing_set = LTC_CRASHING_SET
     elif args.config == "torchdynamo":
         config = TorchDynamoTestConfig(RefBackendLinalgOnTensorsBackend())
         xfail_set = TORCHDYNAMO_XFAIL_SET

e2e_testing/xfail_sets.py

@@ -303,6 +303,9 @@ TORCHDYNAMO_CRASHING_SET = {
     "ToCopyModule_basic",
     "TransposeIntModule_basic",
     "TransposeIntNegDimsModule_basic",
+
+    # See https://github.com/llvm/torch-mlir/issues/2178
+    "Add_Module_basic"
 }
 
 STABLEHLO_PASS_SET = {
@@ -1068,6 +1071,11 @@ TOSA_PASS_SET = {
     "ChunkListUnpackUneven_Module_basic",
 }
 
+LTC_CRASHING_SET = {
+    # https://github.com/llvm/torch-mlir/issues/2186
+    "Add_Module_basic"
+}
+
 LTC_XFAIL_SET = {
     "_Convolution2DAllFalseModule_basic",
     "_Convolution2DBenchmarkModule_basic",

include/torch-mlir/Dialect/Torch/IR/TorchOps.td

@@ -1020,6 +1020,7 @@ def Torch_CopyToNonValueTensorOp : Torch_Op<"copy.to_tensor", [
 }
 
 def Torch_CopyToValueTensorOp : Torch_Op<"copy.to_vtensor", [
+    ReadOnly,
     DeclareOpInterfaceMethods<MemoryEffectsOpInterface>,
     DeclareOpInterfaceMethods<InferTypeOpInterface>,
     TypesMatchWith<"operand is corresponding !torch.tensor",

python/torch_mlir_e2e_test/test_suite/basic.py

@@ -3929,3 +3929,26 @@ class AtenComplexViewModule(torch.nn.Module):
 @register_test_case(module_factory=lambda: AtenComplexViewModule())
 def AtenComplexViewModule_basic(module, tu: TestUtils):
     module.forward(tu.rand(5,2))
+
+
+# ==============================================================================
+
+
+class Add_Module(torch.nn.Module):
+
+    def __init__(self):
+        super().__init__()
+        self.tensor = torch.ones(2, 3)
+
+    @export
+    @annotate_args([
+        None,
+        ([-1, -1], torch.float32, True),
+    ])
+    def forward(self, x):
+        return torch.ops.aten.add_(x, self.tensor)
+
+
+@register_test_case(module_factory=lambda: Add_Module())
+def Add_Module_basic(module, tu: TestUtils):
+    module.forward(tu.rand(2, 3))