Don't check symbol literals for being symbols.

src/hydrogen-instructions.h

 // Copyright 2011 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 1985 matching lines @@
   }
 
   virtual Representation RequiredInputRepresentation(int index) const {
     return Representation::Tagged();
   }
 
 #ifdef DEBUG
   virtual void Verify();
 #endif
 
-  virtual HValue* Canonicalize() {
-    if (!value()->type().IsUninitialized() &&
-        value()->type().IsString() &&
-        check_ == IS_STRING) {
-      return NULL;
-    }
-    return this;
-  }
+  virtual HValue* Canonicalize();
 
   bool is_interval_check() const { return check_ <= LAST_INTERVAL_CHECK; }
   void GetCheckInterval(InstanceType* first, InstanceType* last);
   void GetCheckMaskAndTag(uint8_t* mask, uint8_t* tag);
 
   DECLARE_CONCRETE_INSTRUCTION(CheckInstanceType)
 
  protected:
   // TODO(ager): It could be nice to allow the ommision of instance
   // type checks if we have already performed an instance type check
@@ skipping 2128 matching lines @@
 
   DECLARE_CONCRETE_INSTRUCTION(In)
 };
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_