- Wire the stack frame iterator to use stack maps for traversing objects if there are stack maps in…

vm/raw_object.h

Index: vm/raw_object.h
===================================================================
--- vm/raw_object.h	(revision 5921)
+++ vm/raw_object.h	(working copy)
@@ -251,6 +251,7 @@
 
   void Validate() const;
   intptr_t VisitPointers(ObjectPointerVisitor* visitor);
+  bool FindObject(FindObjectVisitor* visitor);
 
   static RawObject* FromAddr(uword addr) {
     // We expect the untagged address here.
@@ -270,6 +271,8 @@
     return CanonicalObjectTag::decode(value);
   }
 
+  static bool IsRawInstruction(RawObject* raw_obj);
+
  protected:
   RawClass* class_;
   uword tags_;  // Various object tags (bits).
@@ -665,6 +668,14 @@
 
   // Variable length data follows here.
   int32_t data_[0];
+
+  // Private helper function used while visiting stack frames during
+  // GC. The code which iterates over dart frames during GC is not
+  // allowed to create handles.
+  RawStackmap* GetStackmap(uword pc) const;
+
+  friend class DartFrame;
+  friend class StubFrame;
 };
 
 
@@ -677,7 +688,13 @@
   // Variable length data follows here.
   uint8_t data_[0];
 
+  // Private helper function used while visiting stack frames. The
+  // code which iterates over dart frames is also called during GC and
+  // is not allowed to create handles.
+  static bool ContainsPC(RawObject* raw_obj, uword pc);
+
   friend class RawCode;
+  friend class StackFrame;
 };
 
 
@@ -711,9 +728,22 @@
     return reinterpret_cast<RawObject**>(&ptr()->bitmap_size_in_bytes_);
   }
   uword pc_;  // PC corresponding to this stack map representation.
+  intptr_t min_set_bit_offset_;  // Minimum bit offset which is set.
+  intptr_t max_set_bit_offset_;  // Maximum bit offset which is set.
 
   // Variable length data follows here (bitmap of the stack layout).
   uint8_t data_[0];
+
+  // Private helper functions used while visiting stack frames during
+  // GC. The code which iterates over dart frames during GC is not
+  // allowed to create handles.
+  bool IsObject(intptr_t bit_offset) const;
+  uword PC() const { return ptr()->pc_; }
+  intptr_t MinimumBitOffset() const { return ptr()->min_set_bit_offset_; }
+  intptr_t MaximumBitOffset() const { return ptr()->max_set_bit_offset_; }
+
+  friend class RawCode;
+  friend class DartFrame;
 };
 
 
@@ -1031,6 +1061,13 @@
     return reinterpret_cast<RawObject**>(&ptr()->data()[length - 1]);
   }
 
+  // Private helper functions used while visiting stack frames during
+  // GC. The code which iterates over dart frames during GC is not
+  // allowed to create handles.
+  intptr_t Length() const;
+  RawObject* DataAt(intptr_t index) const { return ptr()->data()[index]; }
+
+  friend class RawCode;
   friend class RawImmutableArray;
   friend class SnapshotReader;
   friend class GrowableObjectArray;