Explorer: add trace for `InstantiateType` (#3041)

Adds trace output for `Interpreter::InstantiateType` method.

explorer/interpreter/interpreter.cpp

@@ -502,6 +502,11 @@ auto Interpreter::EvalAssociatedConstant(
 auto Interpreter::InstantiateType(Nonnull<const Value*> type,
                                   SourceLocation source_loc)
     -> ErrorOr<Nonnull<const Value*>> {
+  if (trace_stream_->is_enabled()) {
+    trace_stream_->Start() << "instantiating type `" << *type << "` ("
+                           << source_loc << ")\n";
+  }
+
   switch (type->kind()) {
     case Value::Kind::VariableType: {
       CARBON_ASSIGN_OR_RETURN(

explorer/testdata/trace/phase_execution.carbon

@@ -4,9 +4,10 @@
 
 package ExplorerTest api;
 
-interface TestInterface {}
+class T {}
 
 fn Main() -> i32 {
+  var x: T = {};
   return 0;
 }
 
@@ -19,26 +20,27 @@ fn Main() -> i32 {
 // CHECK:STDOUT: ------------------------------------------------------------
 // CHECK:STDOUT: - - - - -  initializing globals  - - - - -
 // CHECK:STDOUT: ------------------------------------------
-// CHECK:STDOUT: >[] stack-push: DeclarationAction pos: 0 `interface TestInterface` (phase_execution.carbon:7)
-// CHECK:STDOUT: ->> step DeclarationAction pos: 0 `interface TestInterface` (phase_execution.carbon:7) --->
+// CHECK:STDOUT: >[] stack-push: DeclarationAction pos: 0 `class T` (phase_execution.carbon:7)
+// CHECK:STDOUT: ->> step DeclarationAction pos: 0 `class T` (phase_execution.carbon:7) --->
 // CHECK:STDOUT: *** declaration at (phase_execution.carbon:7)
 // CHECK:STDOUT: ```
-// CHECK:STDOUT: interface TestInterface {
+// CHECK:STDOUT: class T {
 // CHECK:STDOUT: }
 // CHECK:STDOUT: ```
-// CHECK:STDOUT: <[] stack-pop:  DeclarationAction pos: 0 `interface TestInterface` (phase_execution.carbon:7)
-// CHECK:STDOUT: >[] stack-push: DeclarationAction pos: 0 `fn Main` (phase_execution.carbon:11)
-// CHECK:STDOUT: ->> step DeclarationAction pos: 0 `fn Main` (phase_execution.carbon:11) --->
-// CHECK:STDOUT: *** declaration at (phase_execution.carbon:11)
+// CHECK:STDOUT: <[] stack-pop:  DeclarationAction pos: 0 `class T` (phase_execution.carbon:7)
+// CHECK:STDOUT: >[] stack-push: DeclarationAction pos: 0 `fn Main` (phase_execution.carbon:12)
+// CHECK:STDOUT: ->> step DeclarationAction pos: 0 `fn Main` (phase_execution.carbon:12) --->
+// CHECK:STDOUT: *** declaration at (phase_execution.carbon:12)
 // CHECK:STDOUT: ```
 // CHECK:STDOUT: fn Main ()-> i32 {
 // CHECK:STDOUT: {
+// CHECK:STDOUT: var x: T = {}.(interface ImplicitAs(T = class T).Convert)();
 // CHECK:STDOUT: return 0;
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: }
 // CHECK:STDOUT: ```
-// CHECK:STDOUT: <[] stack-pop:  DeclarationAction pos: 0 `fn Main` (phase_execution.carbon:11)
+// CHECK:STDOUT: <[] stack-pop:  DeclarationAction pos: 0 `fn Main` (phase_execution.carbon:12)
 // CHECK:STDOUT: - - - - -  calling main function  - - - - -
 // CHECK:STDOUT: -------------------------------------------
 // CHECK:STDOUT: >[] stack-push: ValueExpressionAction pos: 0 `Main()` (<Main()>:0)
@@ -57,40 +59,166 @@ fn Main() -> i32 {
 // CHECK:STDOUT: match pattern ()
 // CHECK:STDOUT: from value expression with value ()
 // CHECK:STDOUT: >[] stack-push: ScopeAction pos: 0  scope: [] (None)
-// CHECK:STDOUT: >[] stack-push: StatementAction pos: 0 `{return 0;}` (phase_execution.carbon:11)
-// CHECK:STDOUT: ->> step StatementAction pos: 0 `{return 0;}` (phase_execution.carbon:11) --->
-// CHECK:STDOUT: *** statement at (phase_execution.carbon:11)
+// CHECK:STDOUT: >[] stack-push: StatementAction pos: 0 `{var x: T = {}.(interface ImplicitAs(T = class T).Convert)();return 0;}` (phase_execution.carbon:12)
+// CHECK:STDOUT: ->> step StatementAction pos: 0 `{var x: T = {}.(interface ImplicitAs(T = class T).Convert)();return 0;}` (phase_execution.carbon:12) --->
+// CHECK:STDOUT: *** statement at (phase_execution.carbon:12)
 // CHECK:STDOUT: ```
 // CHECK:STDOUT: {
+// CHECK:STDOUT: var x: T = {}.(interface ImplicitAs(T = class T).Convert)();
 // CHECK:STDOUT: return 0;
 // CHECK:STDOUT: }
 // CHECK:STDOUT:
 // CHECK:STDOUT: ```
-// CHECK:STDOUT: >[] stack-push: StatementAction pos: 0 `return 0;` (phase_execution.carbon:10)
-// CHECK:STDOUT: ->> step StatementAction pos: 0 `return 0;` (phase_execution.carbon:10) --->
+// CHECK:STDOUT: >[] stack-push: StatementAction pos: 0 `var x: T = {}.(interface ImplicitAs(T = class T).Convert)();` (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step StatementAction pos: 0 `var x: T = {}.(interface ImplicitAs(T = class T).Convert)();` (phase_execution.carbon:10) --->
 // CHECK:STDOUT: *** statement at (phase_execution.carbon:10)
 // CHECK:STDOUT: ```
-// CHECK:STDOUT: return 0;
+// CHECK:STDOUT: var x: T = {}.(interface ImplicitAs(T = class T).Convert)();
 // CHECK:STDOUT: ```
-// CHECK:STDOUT: >[] stack-push: ValueExpressionAction pos: 0 `0` (phase_execution.carbon:10)
-// CHECK:STDOUT: ->> step ValueExpressionAction pos: 0 `0` (phase_execution.carbon:10) --->
-// CHECK:STDOUT: >[] stack-push: ExpressionAction pos: 0 `0` (phase_execution.carbon:10)
-// CHECK:STDOUT: ->> step ExpressionAction pos: 0 `0` (phase_execution.carbon:10) --->
-// CHECK:STDOUT: <[] stack-pop:  ExpressionAction pos: 0 `0` (phase_execution.carbon:10)
-// CHECK:STDOUT: ->> step ValueExpressionAction pos: 1 `0` results: [`0`]  (phase_execution.carbon:10) --->
-// CHECK:STDOUT: <[] stack-pop:  ValueExpressionAction pos: 1 `0` results: [`0`]  (phase_execution.carbon:10)
-// CHECK:STDOUT: ->> step StatementAction pos: 1 `return 0;` results: [`0`]  (phase_execution.carbon:10) --->
-// CHECK:STDOUT: *** statement at (phase_execution.carbon:10)
+// CHECK:STDOUT: ++# memory-alloc: #1 `Uninit<class T>` uninitialized
+// CHECK:STDOUT: >[] stack-push: ExpressionAction pos: 0 `{}.(interface ImplicitAs(T = class T).Convert)()` (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step ExpressionAction pos: 0 `{}.(interface ImplicitAs(T = class T).Convert)()` (phase_execution.carbon:10) --->
+// CHECK:STDOUT: >[] stack-push: ValueExpressionAction pos: 0 `{}.(interface ImplicitAs(T = class T).Convert)` (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step ValueExpressionAction pos: 0 `{}.(interface ImplicitAs(T = class T).Convert)` (phase_execution.carbon:10) --->
+// CHECK:STDOUT: >[] stack-push: ExpressionAction pos: 0 `{}.(interface ImplicitAs(T = class T).Convert)` (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step ExpressionAction pos: 0 `{}.(interface ImplicitAs(T = class T).Convert)` (phase_execution.carbon:10) --->
+// CHECK:STDOUT: >[] stack-push: ValueExpressionAction pos: 0 `{}` (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step ValueExpressionAction pos: 0 `{}` (phase_execution.carbon:10) --->
+// CHECK:STDOUT: >[] stack-push: ExpressionAction pos: 0 `{}` (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step ExpressionAction pos: 0 `{}` (phase_execution.carbon:10) --->
+// CHECK:STDOUT: <[] stack-pop:  ExpressionAction pos: 0 `{}` (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step ValueExpressionAction pos: 1 `{}` results: [`{}`]  (phase_execution.carbon:10) --->
+// CHECK:STDOUT: <[] stack-pop:  ValueExpressionAction pos: 1 `{}` results: [`{}`]  (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step ExpressionAction pos: 1 `{}.(interface ImplicitAs(T = class T).Convert)` results: [`{}`]  (phase_execution.carbon:10) --->
+// CHECK:STDOUT: >[] stack-push: WitnessAction pos: 0 `witness for impl T as ImplicitAs(U)` (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step WitnessAction pos: 0 `witness for impl T as ImplicitAs(U)` (phase_execution.carbon:10) --->
+// CHECK:STDOUT: <[] stack-pop:  WitnessAction pos: 0 `witness for impl T as ImplicitAs(U)` (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step ExpressionAction pos: 2 `{}.(interface ImplicitAs(T = class T).Convert)` results: [`{}`, `witness for impl T as ImplicitAs(U)`]  (phase_execution.carbon:10) --->
+// CHECK:STDOUT: >[] stack-push: TypeInstantiationAction pos: 0 `interface As(T = class T)` (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step TypeInstantiationAction pos: 0 `interface As(T = class T)` (phase_execution.carbon:10) --->
+// CHECK:STDOUT: ->> instantiating type `interface As(T = class T)` (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> instantiating type `class T` (phase_execution.carbon:10)
+// CHECK:STDOUT: <[] stack-pop:  TypeInstantiationAction pos: 0 `interface As(T = class T)` (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step ExpressionAction pos: 3 `{}.(interface ImplicitAs(T = class T).Convert)` results: [`{}`, `witness for impl T as ImplicitAs(U)`, `interface As(T = class T)`]  (phase_execution.carbon:10) --->
+// CHECK:STDOUT: ->> step ExpressionAction pos: 4 `{}.(interface ImplicitAs(T = class T).Convert)` results: [`{}`, `witness for impl T as ImplicitAs(U)`, `interface As(T = class T)`]  (phase_execution.carbon:10) --->
+// CHECK:STDOUT: <[] stack-pop:  ExpressionAction pos: 4 `{}.(interface ImplicitAs(T = class T).Convert)` results: [`{}`, `witness for impl T as ImplicitAs(U)`, `interface As(T = class T)`]  (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step ValueExpressionAction pos: 1 `{}.(interface ImplicitAs(T = class T).Convert)` results: [`bound_method<Convert>`]  (phase_execution.carbon:10) --->
+// CHECK:STDOUT: <[] stack-pop:  ValueExpressionAction pos: 1 `{}.(interface ImplicitAs(T = class T).Convert)` results: [`bound_method<Convert>`]  (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step ExpressionAction pos: 1 `{}.(interface ImplicitAs(T = class T).Convert)()` results: [`bound_method<Convert>`]  scope: [] (phase_execution.carbon:10) --->
+// CHECK:STDOUT: -() calling function: bound_method<Convert>
+// CHECK:STDOUT: match pattern ()
+// CHECK:STDOUT: from value expression with value ()
+// CHECK:STDOUT: >[] stack-push: ScopeAction pos: 0  scope: [`self: Self`: `{}`] (None)
+// CHECK:STDOUT: >[] stack-push: StatementAction pos: 0 `{return __intrinsic_implicit_as_convert(self, U);}` (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ->> step StatementAction pos: 0 `{return __intrinsic_implicit_as_convert(self, U);}` (prelude.carbon:{{\d+}}) --->
+// CHECK:STDOUT: *** statement at (prelude.carbon:{{\d+}})
 // CHECK:STDOUT: ```
-// CHECK:STDOUT: return 0;
+// CHECK:STDOUT: {
+// CHECK:STDOUT: return __intrinsic_implicit_as_convert(self, U);
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
 // CHECK:STDOUT: ```
-// CHECK:STDOUT: <[] stack-pop:  StatementAction pos: 1 `return 0;` results: [`0`]  (phase_execution.carbon:10)
-// CHECK:STDOUT: <[] stack-pop:  StatementAction pos: 1 `{return 0;}` scope: [] (phase_execution.carbon:11)
-// CHECK:STDOUT: <[] stack-pop:  ScopeAction pos: 0  scope: [] (None)
+// CHECK:STDOUT: >[] stack-push: StatementAction pos: 0 `return __intrinsic_implicit_as_convert(self, U);` (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ->> step StatementAction pos: 0 `return __intrinsic_implicit_as_convert(self, U);` (prelude.carbon:{{\d+}}) --->
+// CHECK:STDOUT: *** statement at (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ```
+// CHECK:STDOUT: return __intrinsic_implicit_as_convert(self, U);
+// CHECK:STDOUT: ```
+// CHECK:STDOUT: >[] stack-push: ValueExpressionAction pos: 0 `__intrinsic_implicit_as_convert(self, U)` (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ->> step ValueExpressionAction pos: 0 `__intrinsic_implicit_as_convert(self, U)` (prelude.carbon:{{\d+}}) --->
+// CHECK:STDOUT: >[] stack-push: ExpressionAction pos: 0 `__intrinsic_implicit_as_convert(self, U)` (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ->> step ExpressionAction pos: 0 `__intrinsic_implicit_as_convert(self, U)` (prelude.carbon:{{\d+}}) --->
+// CHECK:STDOUT: <[] stack-pop:  ExpressionAction pos: 0 `__intrinsic_implicit_as_convert(self, U)` (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: >[] stack-push: ExpressionAction pos: 0 `self` (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ->> step ExpressionAction pos: 0 `self` (prelude.carbon:{{\d+}}) --->
+// CHECK:STDOUT: >[] stack-push: ValueExpressionAction pos: 0 `self` (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ->> step ValueExpressionAction pos: 0 `self` (prelude.carbon:{{\d+}}) --->
+// CHECK:STDOUT: >[] stack-push: ExpressionAction pos: 0 `self` (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ->> step ExpressionAction pos: 0 `self` (prelude.carbon:{{\d+}}) --->
+// CHECK:STDOUT: <[] stack-pop:  ExpressionAction pos: 0 `self` (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ->> step ValueExpressionAction pos: 1 `self` results: [`{}`]  (prelude.carbon:{{\d+}}) --->
+// CHECK:STDOUT: <[] stack-pop:  ValueExpressionAction pos: 1 `self` results: [`{}`]  (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ->> step ExpressionAction pos: 1 `self` results: [`{}`]  (prelude.carbon:{{\d+}}) --->
+// CHECK:STDOUT: >[] stack-push: TypeInstantiationAction pos: 0 `class T` (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ->> step TypeInstantiationAction pos: 0 `class T` (prelude.carbon:{{\d+}}) --->
+// CHECK:STDOUT: <[] stack-pop:  TypeInstantiationAction pos: 0 `class T` (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ->> step ExpressionAction pos: 2 `self` results: [`{}`, `class T`]  (prelude.carbon:{{\d+}}) --->
+// CHECK:STDOUT: ->> instantiating type `class T` (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: <[] stack-pop:  ExpressionAction pos: 2 `self` results: [`{}`, `class T`]  (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ->> step ValueExpressionAction pos: 1 `__intrinsic_implicit_as_convert(self, U)` results: [`T{}`]  (prelude.carbon:{{\d+}}) --->
+// CHECK:STDOUT: <[] stack-pop:  ValueExpressionAction pos: 1 `__intrinsic_implicit_as_convert(self, U)` results: [`T{}`]  (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ->> step StatementAction pos: 1 `return __intrinsic_implicit_as_convert(self, U);` results: [`T{}`]  (prelude.carbon:{{\d+}}) --->
+// CHECK:STDOUT: *** statement at (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: ```
+// CHECK:STDOUT: return __intrinsic_implicit_as_convert(self, U);
+// CHECK:STDOUT: ```
+// CHECK:STDOUT: --> memory-write: #1 `T{}`
+// CHECK:STDOUT: <[] stack-pop:  StatementAction pos: 1 `return __intrinsic_implicit_as_convert(self, U);` results: [`T{}`]  (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: <[] stack-pop:  StatementAction pos: 1 `{return __intrinsic_implicit_as_convert(self, U);}` scope: [] (prelude.carbon:{{\d+}})
+// CHECK:STDOUT: <[] stack-pop:  ScopeAction pos: 0  scope: [`self: Self`: `{}`] (None)
+// CHECK:STDOUT: >[] stack-push: CleanUpAction pos: 0  scope: [`self: Self`: `{}`] (stack cleanup:1)
 // CHECK:STDOUT: >[] stack-push: CleanUpAction pos: 0  scope: [] (stack cleanup:1)
+// CHECK:STDOUT: ->> step CleanUpAction pos: 0  scope: [] (stack cleanup:1) --->
+// CHECK:STDOUT: <[] stack-pop:  CleanUpAction pos: 0  scope: [] (stack cleanup:1)
+// CHECK:STDOUT: ->> step CleanUpAction pos: 0  scope: [`self: Self`: `{}`] (stack cleanup:1) --->
+// CHECK:STDOUT: <[] stack-pop:  CleanUpAction pos: 0  scope: [`self: Self`: `{}`] (stack cleanup:1)
+// CHECK:STDOUT: ->> step ExpressionAction pos: 2 `{}.(interface ImplicitAs(T = class T).Convert)()` results: [`bound_method<Convert>`, `T{}`]  scope: [] (phase_execution.carbon:10) --->
+// CHECK:STDOUT: <[] stack-pop:  ExpressionAction pos: 2 `{}.(interface ImplicitAs(T = class T).Convert)()` results: [`bound_method<Convert>`, `T{}`]  scope: [] (phase_execution.carbon:10)
 // CHECK:STDOUT: >[] stack-push: CleanUpAction pos: 0  scope: [] (stack cleanup:1)
 // CHECK:STDOUT: ->> step CleanUpAction pos: 0  scope: [] (stack cleanup:1) --->
 // CHECK:STDOUT: <[] stack-pop:  CleanUpAction pos: 0  scope: [] (stack cleanup:1)
+// CHECK:STDOUT: ->> step StatementAction pos: 1 `var x: T = {}.(interface ImplicitAs(T = class T).Convert)();` results: [`T{}`]  (phase_execution.carbon:10) --->
+// CHECK:STDOUT: *** statement at (phase_execution.carbon:10)
+// CHECK:STDOUT: ```
+// CHECK:STDOUT: var x: T = {}.(interface ImplicitAs(T = class T).Convert)();
+// CHECK:STDOUT: ```
+// CHECK:STDOUT: <-- memory-read: #1 `T{}`
+// CHECK:STDOUT: match pattern Placeholder<x>
+// CHECK:STDOUT: from initializing expression with value T{}
+// CHECK:STDOUT: <[] stack-pop:  StatementAction pos: 1 `var x: T = {}.(interface ImplicitAs(T = class T).Convert)();` results: [`T{}`]  (phase_execution.carbon:10)
+// CHECK:STDOUT: ->> step StatementAction pos: 1 `{var x: T = {}.(interface ImplicitAs(T = class T).Convert)();return 0;}` scope: [`x: T`: `lval<Allocation(1)>`] (phase_execution.carbon:12) --->
+// CHECK:STDOUT: *** statement at (phase_execution.carbon:12)
+// CHECK:STDOUT: ```
+// CHECK:STDOUT: {
+// CHECK:STDOUT: var x: T = {}.(interface ImplicitAs(T = class T).Convert)();
+// CHECK:STDOUT: return 0;
+// CHECK:STDOUT: }
+// CHECK:STDOUT:
+// CHECK:STDOUT: ```
+// CHECK:STDOUT: >[] stack-push: StatementAction pos: 0 `return 0;` (phase_execution.carbon:11)
+// CHECK:STDOUT: ->> step StatementAction pos: 0 `return 0;` (phase_execution.carbon:11) --->
+// CHECK:STDOUT: *** statement at (phase_execution.carbon:11)
+// CHECK:STDOUT: ```
+// CHECK:STDOUT: return 0;
+// CHECK:STDOUT: ```
+// CHECK:STDOUT: >[] stack-push: ValueExpressionAction pos: 0 `0` (phase_execution.carbon:11)
+// CHECK:STDOUT: ->> step ValueExpressionAction pos: 0 `0` (phase_execution.carbon:11) --->
+// CHECK:STDOUT: >[] stack-push: ExpressionAction pos: 0 `0` (phase_execution.carbon:11)
+// CHECK:STDOUT: ->> step ExpressionAction pos: 0 `0` (phase_execution.carbon:11) --->
+// CHECK:STDOUT: <[] stack-pop:  ExpressionAction pos: 0 `0` (phase_execution.carbon:11)
+// CHECK:STDOUT: ->> step ValueExpressionAction pos: 1 `0` results: [`0`]  (phase_execution.carbon:11) --->
+// CHECK:STDOUT: <[] stack-pop:  ValueExpressionAction pos: 1 `0` results: [`0`]  (phase_execution.carbon:11)
+// CHECK:STDOUT: ->> step StatementAction pos: 1 `return 0;` results: [`0`]  (phase_execution.carbon:11) --->
+// CHECK:STDOUT: *** statement at (phase_execution.carbon:11)
+// CHECK:STDOUT: ```
+// CHECK:STDOUT: return 0;
+// CHECK:STDOUT: ```
+// CHECK:STDOUT: <[] stack-pop:  StatementAction pos: 1 `return 0;` results: [`0`]  (phase_execution.carbon:11)
+// CHECK:STDOUT: <[] stack-pop:  StatementAction pos: 2 `{var x: T = {}.(interface ImplicitAs(T = class T).Convert)();return 0;}` scope: [`x: T`: `lval<Allocation(1)>`] (phase_execution.carbon:12)
+// CHECK:STDOUT: <[] stack-pop:  ScopeAction pos: 0  scope: [] (None)
+// CHECK:STDOUT: >[] stack-push: CleanUpAction pos: 0  scope: [] (stack cleanup:1)
+// CHECK:STDOUT: >[] stack-push: CleanUpAction pos: 0  scope: [`x: T`: `lval<Allocation(1)>`] (stack cleanup:1)
+// CHECK:STDOUT: ->> step CleanUpAction pos: 0  scope: [`x: T`: `lval<Allocation(1)>`] (stack cleanup:1) --->
+// CHECK:STDOUT: <-- memory-read: #1 `T{}`
+// CHECK:STDOUT: >[] stack-push: DestroyAction pos: 0  (None)
+// CHECK:STDOUT: ->> step DestroyAction pos: 0  (None) --->
+// CHECK:STDOUT: ->> step DestroyAction pos: 1  (None) --->
+// CHECK:STDOUT: ->> step DestroyAction pos: 2  (None) --->
+// CHECK:STDOUT: <[] stack-pop:  DestroyAction pos: 2  (None)
+// CHECK:STDOUT: ->> step CleanUpAction pos: 1  scope: [`x: T`: `lval<Allocation(1)>`] (stack cleanup:1) --->
+// CHECK:STDOUT: --# memory-dealloc: #1 `T{}`
+// CHECK:STDOUT: ->> step CleanUpAction pos: 2  scope: [`x: T`: `lval<Allocation(1)>`] (stack cleanup:1) --->
+// CHECK:STDOUT: <[] stack-pop:  CleanUpAction pos: 2  scope: [`x: T`: `lval<Allocation(1)>`] (stack cleanup:1)
 // CHECK:STDOUT: ->> step CleanUpAction pos: 0  scope: [] (stack cleanup:1) --->
 // CHECK:STDOUT: <[] stack-pop:  CleanUpAction pos: 0  scope: [] (stack cleanup:1)
 // CHECK:STDOUT: ->> step ExpressionAction pos: 2 `Main()` results: [`fun<Main>`, `0`]  scope: [] (<Main()>:0) --->