One Zone per CompilationInfo.

src/lithium.h

 // Copyright 2012 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 452 matching lines @@
                Zone* zone)
       : closure_(closure),
         frame_type_(frame_type),
         arguments_stack_height_(argument_count),
         deoptimization_index_(Safepoint::kNoDeoptimizationIndex),
         translation_index_(-1),
         ast_id_(ast_id),
         parameter_count_(parameter_count),
         pc_offset_(-1),
         values_(value_count, zone),
-        is_tagged_(value_count, closure->GetHeap()->isolate()->zone()),
+        is_tagged_(value_count, zone),
         spilled_registers_(NULL),
         spilled_double_registers_(NULL),
         outer_(outer),
         zone_(zone) { }
 
   Handle<JSFunction> closure() const { return closure_; }
   FrameType frame_type() const { return frame_type_; }
   int arguments_stack_height() const { return arguments_stack_height_; }
   int deoptimization_index() const { return deoptimization_index_; }
   int translation_index() const { return translation_index_; }
@@ skipping 137 matching lines @@
   ShallowIterator current_iterator_;
 };
 
 
 int ElementsKindToShiftSize(ElementsKind elements_kind);
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_LITHIUM_H_