Add a copied flag to virtual frame elements that tells if a copy has...

src/jump-target.cc

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 252 matching lines @@
         entry_frame_->elements_[i] =
             FrameElement::RegisterElement(reg,
                                           FrameElement::NOT_SYNCED);
       }
     } else {
       // The element is already determined.
       entry_frame_->elements_[i] = *elements[i];
     }
   }
 
+  // Set the copied flags in the frame to be exact.  This assumes that
+  // the backing store of copies is always lower in the frame.
+  for (int i = 0; i < length; i++) {
+    entry_frame_->elements_[i].clear_copied();
+    if (entry_frame_->elements_[i].is_copy()) {
+      int index = entry_frame_->elements_[i].index();
+      entry_frame_->elements_[index].set_copied();
+    }
+  }
+
   // Fill in the other fields of the entry frame.
   entry_frame_->local_count_ = initial_frame->local_count_;
   entry_frame_->frame_pointer_ = initial_frame->frame_pointer_;
 
   // The stack pointer is at the highest synced element or the base of
   // the expression stack.
   int stack_pointer = length - 1;
   while (stack_pointer >= entry_frame_->expression_base_index() &&
          !entry_frame_->elements_[stack_pointer].is_synced()) {
     stack_pointer--;
@@ skipping 350 matching lines @@
   temp.CopyTo(this);
   temp.Reset();  // So the destructor does not deallocate virtual frames.
 
 #ifdef DEBUG
   is_shadowing_ = false;
 #endif
 }
 
 
 } }  // namespace v8::internal