[Inductor] Kill has_aliasing (pytorch#112875)

Pull Request resolved: pytorch#112875
Approved by: https://github.com/Chillee

torch/_inductor/ir.py

@@ -3855,9 +3855,6 @@ def create(cls, *, kernel_idx, grid, kernel_args):
             if isinstance(arg, TensorBox):
                 MutationOutput(arg.layout, arg, packed)
 
-    def has_aliasing(self):
-        return True
-
     def get_alias_names(self):
         return [i.get_name() for i in self.inputs]
 
@@ -3879,9 +3876,6 @@ def is_no_op(self):
     def has_side_effects(self):
         return True
 
-    def has_aliasing(self):
-        return True
-
     def get_alias_names(self):
         return [self.inputs[0].get_name()]
 
@@ -4315,11 +4309,15 @@ def has_side_effects(self):
             return False
         return get_schema_info(self.op_overload).is_mutable()
 
-    def has_aliasing(self):
+    def get_alias_names(self):
         # TODO - some fallbacks are still OpOverloadPackets
         if not isinstance(self.op_overload, torch._ops.OpOverload):
-            return False
-        return torch._inductor.utils.is_view(self.op_overload)
+            return []
+        if torch._inductor.utils.is_view(self.op_overload):
+            # TODO - use op._schema.arguments alias_info to figure out
+            # precise list
+            return [inp.get_name() for inp in self.inputs]
+        return []
 
     # ProxyExecutor Design Note
     # We export the ExternFallbackNodes (for custom ops) into a serialized file
@@ -4494,9 +4492,6 @@ class ComplexView(ExternKernelAlloc):
     def should_allocate(self):
         return False
 
-    def has_aliasing(self):
-        return True
-
     def get_alias_names(self):
         # Signal to codegen that our output buffer isn't safe to reuse
         return [self.inputs[0].get_name()]
@@ -4595,11 +4590,13 @@ def get_unbacked_symbol_uses(self):
     def should_allocate(self):
         return False
 
-    def has_aliasing(self):
-        return any(
-            isinstance(inp, (FallbackKernel, ComplexView)) and inp.has_aliasing()
+    def get_alias_names(self):
+        return [
+            inp.get_name()
             for inp in self.inputs
-        )
+            if isinstance(inp, (FallbackKernel, ComplexView))
+            and len(inp.get_alias_names()) > 0
+        ]
 
 
 def _prepare_convolution_fusion_create(

torch/_inductor/scheduler.py

@@ -332,10 +332,8 @@ def decide_inplace_update(self):
                             ),
                         )
                         and not (
-                            isinstance(
-                                input_node.node, (ir.FallbackKernel, ir.MultiOutput)
-                            )
-                            and input_node.node.has_aliasing()
+                            isinstance(input_node.node, ir.FallbackKernel)
+                            and len(input_node.node.get_alias_names()) > 0
                         )
                         and buffer_reuse_key(input_node.node)
                         == buffer_reuse_key(self.node)