[Static Runtime] Add schema checks for aten::list (#83753)

Summary:
The previous implementation assumed that there was only one overload and unconditionally tried to convert its input into a string. Some users were running into crashes because of this. Added a new overload for the list overload and schema checks.

Also, I managed to uncover another bug when writing tests for this case (yikes). Returning inputs didn't work because the input cleanup process would destroy the output. Extended `CreateOwnedRefsForSpecialIValues` to fix that.

Test Plan: CI + new unit tests

Differential Revision: D38870803

Pull Request resolved: https://github.com/pytorch/pytorch/pull/83753
Approved by: https://github.com/tenpercent, https://github.com/albanD

benchmarks/static_runtime/test_static_runtime.cc

@@ -2595,23 +2595,28 @@ TEST(StaticRuntime, JIT_Aten_Numel) {
 }
 
 TEST(StaticRuntime, JIT_Aten_List) {
-  const std::string script = R"IR(
+  const auto script_str = R"IR(
     graph(%a: str):
-        %1 : int = prim::Constant[value=0]()
         %ret: str[] = aten::list(%a)
         return (%ret)
   )IR";
-
-  auto graph = std::make_shared<Graph>();
-  std::unordered_map<std::string, Value*> vmap;
-  vmap.reserve(0);
-  parseIR(script, graph.get(), vmap);
-  torch::jit::StaticModule smodule(graph);
-
-  string a = "abcd";
+  std::string a = "abcd";
   std::vector<IValue> args0{a};
+  testStaticRuntime(script_str, args0);
 
-  testStaticRuntime(script, args0);
+  // Update the result of aten::list to ensure that a deep copy
+  // took place
+  const auto script_list = R"IR(
+    graph(%a : int[]):
+        %idx : int = prim::Constant[value=0]()
+        %value : int = prim::Constant[value=42]()
+        %res : int[] = aten::list(%a)
+        %updated : int[] = aten::_set_item(%res, %idx, %value)
+        return (%res, %a)
+  )IR";
+
+  std::vector<IValue> args1{c10::List<int64_t>{1, 2, 3}};
+  testStaticRuntime(script_list, args1);
 }
 
 TEST(StaticRuntime, JIT_Aten_Range_Length) {

torch/csrc/jit/runtime/static/native_ops.cpp

@@ -204,15 +204,27 @@ REGISTER_NATIVE_OPERATOR_FUNCTOR(
     aten::list,
     aten_list,
     [](Node* n) -> SROperator {
-      return [](ProcessedNode* p_node) {
-        const auto str = p_node->Input(0).toStringRef();
-        c10::List<std::string> chars;
-        chars.reserve(str.size());
-        for (auto c : str) {
-          chars.emplace_back(1, c);
-        }
-        p_node->Output(0) = std::move(chars);
-      };
+      if (n->matches(torch::schema("aten::list(str t) -> str[]"))) {
+        return [](ProcessedNode* p_node) {
+          const auto str = p_node->Input(0).toStringRef();
+          c10::List<std::string> chars;
+          chars.reserve(str.size());
+          for (auto c : str) {
+            chars.emplace_back(1, c);
+          }
+          p_node->Output(0) = std::move(chars);
+        };
+      }
+
+      if (n->matches(torch::schema("aten::list.t(t[] l) -> t[]"))) {
+        return [](ProcessedNode* p_node) {
+          const auto input = p_node->Input(0).toList();
+          p_node->Output(0) = input.copy();
+        };
+      }
+
+      LogAndDumpSchema(n);
+      return nullptr;
     });
 
 REGISTER_NATIVE_OPERATOR_FUNCTOR(

torch/csrc/jit/runtime/static/passes.cpp

@@ -1043,6 +1043,10 @@ void CreateOwnedRefsForSpecialValuesHelper(Graph& graph, Block* block) {
   }
 
   auto outputs = block->outputs();
+  // Create owned refs for inputs. Otherwise, the input cleanup process
+  // will destroy our outputs before we return.
+  FastSet<Value*> inputs = {block->inputs().begin(), block->inputs().end()};
+
   for (const auto i : c10::irange(outputs.size())) {
     auto* output = outputs[i];
 
@@ -1052,7 +1056,7 @@ void CreateOwnedRefsForSpecialValuesHelper(Graph& graph, Block* block) {
       continue;
     }
 
-    if (toIValue(output).has_value() ||
+    if ((inputs.find(output) != inputs.end()) || toIValue(output).has_value() ||
         // If the output's owning block is not this one, it's from an outer
         // scope
         output->node()->owningBlock() != block) {