- WeakProperty keys in other generations are black. Avoid trying to

vm/object_test.cc

Index: vm/object_test.cc
===================================================================
--- vm/object_test.cc	(revision 13085)
+++ vm/object_test.cc	(working copy)
@@ -2865,6 +2865,120 @@
 }
 
 
+TEST_CASE(WeakProperty_PreserveCrossGen) {
+  Isolate* isolate = Isolate::Current();
+  WeakProperty& weak = WeakProperty::Handle();
+  {
+    // Weak property and value in new. Key in old.
+    HANDLESCOPE(isolate);
+    OneByteString& key = OneByteString::Handle();
+    key ^= OneByteString::New("key", Heap::kOld);
+    OneByteString& value = OneByteString::Handle();
+    value ^= OneByteString::New("value", Heap::kNew);
+    weak ^= WeakProperty::New(Heap::kNew);
+    weak.set_key(key);
+    weak.set_value(value);
+    key ^= OneByteString::null();
+    value ^= OneByteString::null();
+  }
+  isolate->heap()->CollectAllGarbage();
+  // Weak property key and value should survive due to cross-generation
+  // pointers.
+  EXPECT(weak.key() != Object::null());
+  EXPECT(weak.value() != Object::null());
+  {
+    // Weak property and value in old. Key in new.
+    HANDLESCOPE(isolate);
+    OneByteString& key = OneByteString::Handle();
+    key ^= OneByteString::New("key", Heap::kNew);
+    OneByteString& value = OneByteString::Handle();
+    value ^= OneByteString::New("value", Heap::kOld);
+    weak ^= WeakProperty::New(Heap::kOld);
+    weak.set_key(key);
+    weak.set_value(value);
+    key ^= OneByteString::null();
+    value ^= OneByteString::null();
+  }
+  isolate->heap()->CollectAllGarbage();
+  // Weak property key and value should survive due to cross-generation
+  // pointers.
+  EXPECT(weak.key() != Object::null());
+  EXPECT(weak.value() != Object::null());
+  {
+    // Weak property and value in new. Key is a Smi.
+    HANDLESCOPE(isolate);
+    Integer& key = Integer::Handle();
+    key ^= Integer::New(31);
+    OneByteString& value = OneByteString::Handle();
+    value ^= OneByteString::New("value", Heap::kNew);
+    weak ^= WeakProperty::New(Heap::kNew);
+    weak.set_key(key);
+    weak.set_value(value);
+    key ^= Integer::null();
+    value ^= OneByteString::null();
+  }
+  isolate->heap()->CollectAllGarbage();
+  // Weak property key and value should survive due to cross-generation

[cshapiro, 2012/10/01 22:22:14]

This comment is false, no?  The key is implicitly live because it is not a heap
object.

[Ivan Posva, 2012/10/01 22:27:39]

Done.

+  // pointers.
+  EXPECT(weak.key() != Object::null());
+  EXPECT(weak.value() != Object::null());
+  {
+    // Weak property and value in old. Key is a Smi.
+    HANDLESCOPE(isolate);
+    Integer& key = Integer::Handle();
+    key ^= Integer::New(32);
+    OneByteString& value = OneByteString::Handle();
+    value ^= OneByteString::New("value", Heap::kOld);
+    weak ^= WeakProperty::New(Heap::kOld);
+    weak.set_key(key);
+    weak.set_value(value);
+    key ^= OneByteString::null();
+    value ^= OneByteString::null();
+  }
+  isolate->heap()->CollectAllGarbage();
+  // Weak property key and value should survive due to cross-generation

[cshapiro, 2012/10/01 22:22:14]

Same here.

[Ivan Posva, 2012/10/01 22:27:39]

Done.

+  // pointers.
+  EXPECT(weak.key() != Object::null());
+  EXPECT(weak.value() != Object::null());
+  {
+    // Weak property and value in new. Key in VM isolate.
+    HANDLESCOPE(isolate);
+    OneByteString& key = OneByteString::Handle();
+    key ^= Symbols::Dot();
+    OneByteString& value = OneByteString::Handle();
+    value ^= OneByteString::New("value", Heap::kNew);
+    weak ^= WeakProperty::New(Heap::kNew);
+    weak.set_key(key);
+    weak.set_value(value);
+    key ^= OneByteString::null();
+    value ^= OneByteString::null();
+  }
+  isolate->heap()->CollectAllGarbage();
+  // Weak property key and value should survive due to cross-generation
+  // pointers.
+  EXPECT(weak.key() != Object::null());
+  EXPECT(weak.value() != Object::null());
+  {
+    // Weak property and value in old. Key in VM isolate.
+    HANDLESCOPE(isolate);
+    OneByteString& key = OneByteString::Handle();
+    key ^= Symbols::Dot();
+    OneByteString& value = OneByteString::Handle();
+    value ^= OneByteString::New("value", Heap::kOld);
+    weak ^= WeakProperty::New(Heap::kOld);
+    weak.set_key(key);
+    weak.set_value(value);
+    key ^= OneByteString::null();
+    value ^= OneByteString::null();
+  }
+  isolate->heap()->CollectAllGarbage();
+  // Weak property key and value should survive due to cross-generation
+  // pointers.
+  EXPECT(weak.key() != Object::null());
+  EXPECT(weak.value() != Object::null());
+}
+
+
 TEST_CASE(WeakProperty_PreserveOne_NewSpace) {
   Isolate* isolate = Isolate::Current();
   WeakProperty& weak = WeakProperty::Handle();