Fix bug with CHA dependencies by recording a set of classes for registering code.

runtime/vm/flow_graph_type_propagator.cc

Index: runtime/vm/flow_graph_type_propagator.cc
===================================================================
--- runtime/vm/flow_graph_type_propagator.cc	(revision 39070)
+++ runtime/vm/flow_graph_type_propagator.cc	(working copy)
@@ -523,10 +523,10 @@
       cid_ = kNullCid;
     } else if (type_->HasResolvedTypeClass()) {
       const Class& type_class = Class::Handle(type_->type_class());
-      if (FLAG_use_cha || IsKnownPrivateClass(type_class)) {
+      if (FLAG_use_cha && IsKnownPrivateClass(type_class)) {

[Florian Schneider, 2014/08/12 11:37:10]

This is the fix for bug #1.

[Vyacheslav Egorov (Google), 2014/08/12 12:16:56]

Something is not right here. I suggest we just kill IsKnownPrivateClass(), I
don't think it is necessary anymore.

[Florian Schneider, 2014/08/13 10:34:40]

Done. Also removed HasSubclassesSafe. There is only one version now. I also
added CHA::IsImplemented to track interface implementation properly.

         // A known private class cannot be subclassed or implemented.
         if (!type_class.is_implemented() &&
-            !CHA::HasSubclassesSafe(type_class.id())) {
+            !Isolate::Current()->cha()->HasSubclassesSafe(type_class.id())) {
           cid_ = type_class.id();
         } else {
           cid_ = kDynamicCid;
@@ -743,7 +743,7 @@
     intptr_t cid = kDynamicCid;
     if (FLAG_use_cha && type.HasResolvedTypeClass()) {
       const Class& type_class = Class::Handle(type.type_class());
-      if (!CHA::HasSubclasses(type_class.id())) {
+      if (!Isolate::Current()->cha()->HasSubclasses(type_class.id())) {
         cid = type_class.id();
       }
     }
@@ -788,15 +788,18 @@
     return ZoneCompileType::Wrap(CompileType::Null());
   }
 
-  return ZoneCompileType::Wrap(CompileType::FromAbstractType(dst_type()));
+  return ZoneCompileType::Wrap(
+      CompileType::FromAbstractType(dst_type(), value_type->is_nullable()));

[Florian Schneider, 2014/08/12 11:37:10]

This line and the change below add tracking of nullability through
AssertAssignable which was missing before.

 }
 
 
 bool AssertAssignableInstr::RecomputeType() {
   CompileType* value_type = value()->Type();
-  return UpdateType(value_type->IsMoreSpecificThan(dst_type())
-                      ? *value_type
-                      : CompileType::FromAbstractType(dst_type()));
+  return UpdateType(
+      value_type->IsMoreSpecificThan(dst_type())
+          ? *value_type
+          : CompileType::FromAbstractType(dst_type(),
+                                          value_type->is_nullable()));
 }