Preserve Smi representation of non-escaping fields.

src/hydrogen-instructions.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
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 //
 //     * Redistributions of source code must retain the above copyright
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@@ skipping 1710 matching lines @@
   HValue* value() { return OperandAt(0); }
 
   virtual Representation RequiredInputRepresentation(int index) V8_OVERRIDE {
     return representation();  // Same as the output representation.
   }
 
   virtual void PrintDataTo(StringStream* stream) V8_OVERRIDE;
 
   DECLARE_CONCRETE_INSTRUCTION(ForceRepresentation)
 
- private:

[Michael Starzinger, 2014/04/25 08:35:10]

Let's keep this constructor private and use HForceRepresentation::New instead,
that gives us implicit constant folding.

[Jarin, 2014/04/25 11:05:07]

Done.

   HForceRepresentation(HValue* value, Representation required_representation) {
     SetOperandAt(0, value);
     set_representation(required_representation);
   }
 };
 
 
 class HChange V8_FINAL : public HUnaryOperation {
  public:
   HChange(HValue* value,
@@ skipping 5824 matching lines @@
   virtual bool IsDeletable() const V8_OVERRIDE { return true; }
 };
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_