Merge pull request #12026 from felipepiovezan/felipe/fix_var_not_captured

[lldb] Fix GetParentIfClosure for async closures inside non-async functions

Author: adrian-prantl

lldb/source/Plugins/LanguageRuntime/Swift/SwiftLanguageRuntimeNames.cpp

@@ -1600,16 +1600,38 @@ std::string SwiftLanguageRuntime::GetParentNameIfClosure(Function &func) {
       swift_demangle::GetFirstChildOfKind(closure_node, function_kinds);
   if (!parent_func_node)
     return "";
-  swift_demangle::ReplaceChildWith(*node, *closure_node, *parent_func_node);
 
-  ManglingErrorOr<std::string> mangled = swift::Demangle::mangleNode(node);
+  NodeFactory factory;
+  Node *new_global = factory.createNode(Kind::Global);
+  if (!new_global)
+    return "";
+  // For a given function-like node, async information is a sibling - not a
+  // child - of the node in the demangling tree. Bring that over as well.
+  // Don't bring all children, however, as the closure number of `closure_node`
+  // is also a child of `closure_node`, i.e., it is not related to
+  // `parent_func_node`.
+  //
+  // node (Global)
+  // |
+  // |- closure_node
+  //    |- parent_func_node (any function_kind)
+  //    |- async info for parent_func_node
+  //    |- closure number for closure_node
+  for (auto *child : *closure_node)
+    if (child->getKind() == Kind::AsyncAwaitResumePartialFunction ||
+        child->getKind() == Kind::AsyncSuspendResumePartialFunction)
+      new_global->addChild(child, factory);
+  new_global->addChild(parent_func_node, factory);
+
+  ManglingErrorOr<std::string> mangled =
+      swift::Demangle::mangleNode(new_global);
   if (!mangled.isSuccess())
     return "";
 
   if (parent_func_node->getKind() == Kind::Constructor)
     if (Module *module = func.CalculateSymbolContextModule().get())
-      return HandleCtorAndAllocatorVariants(mangled.result(), *module, *node,
-                                            *parent_func_node);
+      return HandleCtorAndAllocatorVariants(mangled.result(), *module,
+                                            *new_global, *parent_func_node);
   return mangled.result();
 }
 } // namespace lldb_private

lldb/source/Plugins/TypeSystem/Swift/SwiftDemangle.h

@@ -41,9 +41,10 @@ inline NodePointer GetFirstChildOfKind(NodePointer node,
 inline void ReplaceChildWith(Node &parent, Node &to_replace, Node &new_child) {
   for (unsigned idx = 0; idx < parent.getNumChildren(); idx++) {
     auto *child = parent.getChild(idx);
-    if (child == &to_replace)
+    if (child == &to_replace) {
       parent.replaceChild(idx, &new_child);
-    return;
+      return;
+    }
   }
   llvm_unreachable("invalid child passed to replaceChildWith");
 }

lldb/test/API/lang/swift/closures_var_not_captured/TestSwiftClosureVarNotCaptured.py

@@ -106,6 +106,18 @@ def test_async_closure(self):
         )
         check_no_enhanced_diagnostic(self, thread.frames[0], "dont_find_me")
 
+    @swiftTest
+    # Async variable inspection on Linux/Windows are still problematic.
+    @skipIf(oslist=["windows", "linux"])
+    def test_task_inside_non_async_func(self):
+        self.build()
+        (target, process, thread) = self.get_to_bkpt(
+            "break_task_inside_non_async_function"
+        )
+        check_not_captured_error(
+            self, thread.frames[0], "x", "task_inside_non_async_function()"
+        )
+
     @swiftTest
     def test_ctor_class_closure(self):
         self.build()

lldb/test/API/lang/swift/closures_var_not_captured/main.swift

@@ -212,6 +212,18 @@ enum MY_ENUM {
   }
 }
 
+func async_foo() async {}
+
+func task_inside_non_async_function() -> Task<Void, Never> {
+  var x = 10;
+  var task = Task {
+    await async_foo()
+    print("break_task_inside_non_async_function")
+  }
+
+  return task
+}
+
 func_1(arg: 42)
 func_2(arg: 42)
 await func_3(arg: 42)
@@ -227,3 +239,4 @@ my_struct.struct_computed_property = 10
 my_struct.struct_computed_property_didset = 10
 let _ = MY_ENUM(input: [1,2])
 MY_ENUM.static_func(input_static: [42])
+await task_inside_non_async_function().getResult()