This patch is an effort to simplify cascading jumps to return label in such case:

src/full-codegen.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 73 matching lines @@
         nesting_stack_(NULL),
         loop_depth_(0),
         global_count_(0),
         context_(NULL),
         bailout_entries_(info->HasDeoptimizationSupport()
                          ? info->function()->ast_node_count() : 0),
         stack_checks_(2),  // There's always at least one.
         type_feedback_cells_(info->HasDeoptimizationSupport()
                              ? info->function()->ast_node_count() : 0),
         ic_total_count_(0),
-        has_self_optimization_header_(false) { }
+        has_self_optimization_header_(false),
+        immediate_return_enabled_(false) { }
 
   static bool MakeCode(CompilationInfo* info);
 
   // Returns the platform-specific size in bytes of the self-optimization
   // header.
   static int self_optimization_header_size();
 
   // Encode state and pc-offset as a BitField<type, start, size>.
   // Only use 30 bits because we encode the result as a smi.
   class StateField : public BitField<State, 0, 1> { };
@@ skipping 450 matching lines @@
   bool is_native() { return info_->is_native(); }
   bool is_classic_mode() {
     return language_mode() == CLASSIC_MODE;
   }
   LanguageMode language_mode() {
     return function()->language_mode();
   }
   FunctionLiteral* function() { return info_->function(); }
   Scope* scope() { return scope_; }
 
+  bool immediate_return_enabled() { return immediate_return_enabled_; }
+
   static Register result_register();
   static Register context_register();
 
   // Set fields in the stack frame. Offsets are the frame pointer relative
   // offsets defined in, e.g., StandardFrameConstants.
   void StoreToFrameField(int frame_offset, Register value);
 
   // Load a value from the current context. Indices are defined as an enum
   // in v8::internal::Context.
   void LoadContextField(Register dst, int context_index);
@@ skipping 84 matching lines @@
     virtual bool IsEffect() const { return false; }
 
     // Returns true if we are evaluating for the value (in accu/on stack).
     virtual bool IsAccumulatorValue() const { return false; }
     virtual bool IsStackValue() const { return false; }
 
     // Returns true if we are branching on the value rather than materializing
     // it.  Only used for asserts.
     virtual bool IsTest() const { return false; }
 
+    // Returns true if we are branching on the value that can be returned.
+    virtual bool IsReturnable() const { return false; }
+
    protected:
     FullCodeGenerator* codegen() const { return codegen_; }
     MacroAssembler* masm() const { return masm_; }
     MacroAssembler* masm_;
 
    private:
     const ExpressionContext* old_;
     FullCodeGenerator* codegen_;
   };
 
   class AccumulatorValueContext : public ExpressionContext {
    public:
     explicit AccumulatorValueContext(FullCodeGenerator* codegen)
         : ExpressionContext(codegen) { }
 
     virtual void Plug(bool flag) const;
     virtual void Plug(Register reg) const;
     virtual void Plug(Label* materialize_true, Label* materialize_false) const;
     virtual void Plug(Variable* var) const;
     virtual void Plug(Handle<Object> lit) const;
     virtual void Plug(Heap::RootListIndex) const;
     virtual void PlugTOS() const;
     virtual void DropAndPlug(int count, Register reg) const;
     virtual void PrepareTest(Label* materialize_true,
                              Label* materialize_false,
                              Label** if_true,
                              Label** if_false,
                              Label** fall_through) const;
     virtual bool IsAccumulatorValue() const { return true; }
+    virtual bool IsReturnable() const {
+      return codegen()->immediate_return_enabled();
+    }
   };
 
   class StackValueContext : public ExpressionContext {
    public:
     explicit StackValueContext(FullCodeGenerator* codegen)
         : ExpressionContext(codegen) { }
 
     virtual void Plug(bool flag) const;
     virtual void Plug(Register reg) const;
     virtual void Plug(Label* materialize_true, Label* materialize_false) const;
@@ skipping 69 matching lines @@
     virtual void PlugTOS() const;
     virtual void DropAndPlug(int count, Register reg) const;
     virtual void PrepareTest(Label* materialize_true,
                              Label* materialize_false,
                              Label** if_true,
                              Label** if_false,
                              Label** fall_through) const;
     virtual bool IsEffect() const { return true; }
   };
 
+  class ImmediateReturnEnabled {
+   public:
+    explicit ImmediateReturnEnabled(FullCodeGenerator* codegen)
+      : codegen_(codegen), old_(codegen->immediate_return_enabled_) {
+        codegen_->immediate_return_enabled_ = true;
+    }
+    virtual ~ImmediateReturnEnabled() {
+        codegen_->immediate_return_enabled_ = old_;
+    }
+
+   private:
+    FullCodeGenerator* codegen_;
+    bool old_;
+  };
+
+  class ImmediateReturnDisabled {
+   public:
+    explicit ImmediateReturnDisabled(FullCodeGenerator* codegen)
+      : codegen_(codegen), old_(codegen->immediate_return_enabled_) {
+        codegen_->immediate_return_enabled_ = false;
+    }
+    virtual ~ImmediateReturnDisabled() {
+        codegen_->immediate_return_enabled_ = old_;
+    }
+
+   private:
+    FullCodeGenerator* codegen_;
+    bool old_;
+  };
+
   MacroAssembler* masm_;
   CompilationInfo* info_;
   Scope* scope_;
   Label return_label_;
   NestedStatement* nesting_stack_;
   int loop_depth_;
   int global_count_;
   const ExpressionContext* context_;
   ZoneList<BailoutEntry> bailout_entries_;
   ZoneList<BailoutEntry> stack_checks_;
   ZoneList<TypeFeedbackCellEntry> type_feedback_cells_;
   int ic_total_count_;
   bool has_self_optimization_header_;
   Handle<FixedArray> handler_table_;
   Handle<JSGlobalPropertyCell> profiling_counter_;
+  bool immediate_return_enabled_;
 
   friend class NestedStatement;
 
   DISALLOW_COPY_AND_ASSIGN(FullCodeGenerator);
 };
 
 
 // A map from property names to getter/setter pairs allocated in the zone.
 class AccessorTable: public TemplateHashMap<Literal,
                                             ObjectLiteral::Accessors,
@@ skipping 12 matching lines @@
   }
 
  private:
   Zone* zone_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_FULL_CODEGEN_H_