commit 94f7b49578b6aaa80de8ffed230648d601393905
author Hiroshi Yamauchi <yamauchi@google.com> Tue Jul 22 18:08:23 2014 -0700
committer Hiroshi Yamauchi <yamauchi@google.com> Tue Jul 29 13:30:46 2014 -0700
tree cfc69e453faefee38178ceb85378e1f0f1e17812
parent 8df73882c60451e7f789bf9b1f3db2d7dc228640

Add GcRoot to clean up and enforce read barriers.

Introduce a value-type wrapper around Object* for GC roots so that 1)
we won't have to directly add the read barrier code in many places and
2) we can avoid accidentally bypassing/missing read barriers on GC
roots (the GcRoot interface ensures that the read barrier is executed
on a read).

The jdwp test passed.

Bug: 12687968
Change-Id: Ib167c7c325b3c7e3900133578815f04d219972a1

runtime/mirror/array.h

diff --git a/runtime/mirror/array.h b/runtime/mirror/array.h
index 6588b57..7af88d6 100644
--- a/runtime/mirror/array.h
+++ b/runtime/mirror/array.h
@@ -17,10 +17,10 @@
 #ifndef ART_RUNTIME_MIRROR_ARRAY_H_
 #define ART_RUNTIME_MIRROR_ARRAY_H_
 
+#include "gc_root.h"
 #include "gc/allocator_type.h"
 #include "object.h"
 #include "object_callbacks.h"
-#include "read_barrier.h"
 
 namespace art {
 
@@ -159,27 +159,26 @@
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   static void SetArrayClass(Class* array_class) {
-    CHECK(array_class_ == nullptr);
+    CHECK(array_class_.IsNull());
     CHECK(array_class != nullptr);
-    array_class_ = array_class;
+    array_class_ = GcRoot<Class>(array_class);
   }
 
   static Class* GetArrayClass() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
-    DCHECK(array_class_ != nullptr);
-    return ReadBarrier::BarrierForRoot<mirror::Class, kWithReadBarrier>(
-        &array_class_);
+    DCHECK(!array_class_.IsNull());
+    return array_class_.Read();
   }
 
   static void ResetArrayClass() {
-    CHECK(array_class_ != nullptr);
-    array_class_ = nullptr;
+    CHECK(!array_class_.IsNull());
+    array_class_ = GcRoot<Class>(nullptr);
   }
 
   static void VisitRoots(RootCallback* callback, void* arg)
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
  private:
-  static Class* array_class_;
+  static GcRoot<Class> array_class_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(PrimitiveArray);
 };