Compile FastCloneShallowObjectStub using Crankshaft.

src/hydrogen.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 894 matching lines @@
       HValue* val,
       HCheckMaps* mapcheck,
       bool is_js_array,
       ElementsKind elements_kind,
       bool is_store,
       Representation checked_index_representation = Representation::None());
 
   HInstruction* BuildStoreMap(HValue* object, HValue* map, BailoutId id);
   HInstruction* BuildStoreMap(HValue* object, Handle<Map> map, BailoutId id);
 
+  class CheckBuilder {
+   public:
+    CheckBuilder(HGraphBuilder* builder,
+                 BailoutId id = BailoutId::StubEntry());

[danno, 2013/02/11 14:34:27]

I think it's a good idea to not provide a default. If this builder ever gets
used in an inlined stub in a JS function, then it will need the right ast_id,
and with the default construction it's easy to forget to thread it through. 

[Michael Starzinger, 2013/02/11 16:31:11]

Done (also for the other builders below).

+    ~CheckBuilder() {
+      if (!finished_) End();
+    }
+
+    void CheckNotUndefined(HValue* value);
+    void CheckIntegerEq(HValue* left, HValue* right);
+    void End();
+
+   private:
+    Zone* zone() { return builder_->zone(); }
+
+    HGraphBuilder* builder_;
+    bool finished_;
+    HBasicBlock* failure_block_;
+    HBasicBlock* merge_block_;
+    BailoutId id_;
+  };
+
   class IfBuilder {
    public:
     IfBuilder(HGraphBuilder* builder,
               BailoutId id = BailoutId::StubEntry());
     ~IfBuilder() {
       if (!finished_) End();
     }
 
     void BeginTrue(HValue* left, HValue* right, Token::Value token);
     void BeginFalse();
     void End();
 
    private:
+    Zone* zone() { return builder_->zone(); }
+
     HGraphBuilder* builder_;
     bool finished_;
     HBasicBlock* true_block_;
     HBasicBlock* false_block_;
     HBasicBlock* merge_block_;
     BailoutId id_;
-
-    Zone* zone() { return builder_->zone(); }
   };
 
   class LoopBuilder {
    public:
     enum Direction {
       kPreIncrement,
       kPostIncrement,
       kPreDecrement,
       kPostDecrement
     };
 
     LoopBuilder(HGraphBuilder* builder,
                 HValue* context,
                 Direction direction,
                 BailoutId id = BailoutId::StubEntry());
     ~LoopBuilder() {
       ASSERT(finished_);
     }
 
     HValue* BeginBody(HValue* initial, HValue* terminating, Token::Value token);
     void EndBody();
 
    private:
+    Zone* zone() { return builder_->zone(); }
+
     HGraphBuilder* builder_;
     HValue* context_;
     HInstruction* increment_;
     HPhi* phi_;
     HBasicBlock* header_block_;
     HBasicBlock* body_block_;
     HBasicBlock* exit_block_;
     Direction direction_;
     BailoutId id_;
     bool finished_;
-
-    Zone* zone() { return builder_->zone(); }
   };
 
   HValue* BuildAllocateElements(HContext* context,
                                 ElementsKind kind,
                                 HValue* capacity);
 
   void BuildCopyElements(HContext* context,
                          HValue* from_elements,
                          ElementsKind from_elements_kind,
                          HValue* to_elements,
@@ skipping 673 matching lines @@
   const char* filename_;
   HeapStringAllocator string_allocator_;
   StringStream trace_;
   int indent_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_H_