Update native gc-roots separately in compaction pause

The concurrent compaction algorithm requires all GC roots to be updated
to post-compact addresses before resuming mutators for concurrent
compaction. Therefore, unlike CC, we cannot update native roots in
classes/dex-caches/class-loaders while visiting references
(VisitReferences) on heap objects.

This CL separates the two and updates all the gc-roots in the compaction
pause.

Bug: 160737021
Test: art/test/testrunner/testrunner.py
Change-Id: I8a57472ba49b9dc30bc0f41a7db3f5efa7eafd9a

1 files changed, 9 insertions, 0 deletions

diff --git a/runtime/class_table.h b/runtime/class_table.h
index 212a7d6631..123c069f0e 100644
--- a/runtime/class_table.h
+++ b/runtime/class_table.h
@@ -85,6 +85,9 @@ class ClassTable {
     template<typename Visitor>
     void VisitRoot(const Visitor& visitor) const NO_THREAD_SAFETY_ANALYSIS;
 
+    template<typename Visitor>
+    class ClassAndRootVisitor;
+
    private:
     // Extract a raw pointer from an address.
     static ObjPtr<mirror::Class> ExtractPtr(uint32_t data)
@@ -185,6 +188,12 @@ class ClassTable {
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);
 
+  template<class Visitor>
+  void VisitClassesAndRoots(Visitor& visitor)
+      NO_THREAD_SAFETY_ANALYSIS
+      REQUIRES(!lock_)
+      REQUIRES_SHARED(Locks::mutator_lock_);
+
   // Stops visit if the visitor returns false.
   template <ReadBarrierOption kReadBarrierOption = kWithReadBarrier, typename Visitor>
   bool Visit(Visitor& visitor)