Pass checked values to HLoadNamedField, removing the need for extra type-check field.

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
 // 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 1341 matching lines @@
   virtual void PrintDataTo(StringStream* stream);
 
   Handle<Map> map() const { return map_; }
 
   virtual Representation RequiredInputRepresentation(int index) {
     return Representation::Tagged();
   }
 
   DECLARE_CONCRETE_INSTRUCTION(CompareMap)
 
+ protected:
+  virtual int RedefinedOperandIndex() { return 0; }
+
  private:
   Handle<Map> map_;
 };
 
 
 class HContext: public HTemplateInstruction<0> {
  public:
   static HContext* New(Zone* zone) {
     return new(zone) HContext();
   }
@@ skipping 1219 matching lines @@
       return false;
     }
     for (int i = 0; i < map_unique_ids_.length(); i++) {
       if (map_unique_ids_.at(i) != b->map_unique_ids_.at(i)) {
         return false;
       }
     }
     return true;
   }
 
+  virtual int RedefinedOperandIndex() { return 0; }
+
  private:
   // Clients should use one of the static New* methods above.
   HCheckMaps(HValue* value, Zone *zone, HValue* typecheck)
       : HTemplateInstruction<2>(value->type()),
         omit_(false), has_migration_target_(false), map_unique_ids_(0, zone) {
     SetOperandAt(0, value);
     // Use the object value for the dependency if NULL is passed.
     // TODO(titzer): do GVN flags already express this dependency?
     SetOperandAt(1, typecheck != NULL ? typecheck : value);
     set_representation(Representation::Tagged());
@@ skipping 96 matching lines @@
 
  protected:
   // TODO(ager): It could be nice to allow the ommision of instance
   // type checks if we have already performed an instance type check
   // with a larger range.
   virtual bool DataEquals(HValue* other) {
     HCheckInstanceType* b = HCheckInstanceType::cast(other);
     return check_ == b->check_;
   }
 
+  virtual int RedefinedOperandIndex() { return 0; }
+
  private:
   enum Check {
     IS_SPEC_OBJECT,
     IS_JS_ARRAY,
     IS_STRING,
     IS_INTERNALIZED_STRING,
     LAST_INTERVAL_CHECK = IS_JS_ARRAY
   };
 
   const char* GetCheckName();
@@ skipping 2821 matching lines @@
 
   friend class HLoadNamedField;
   friend class HStoreNamedField;
 
   inline Portion portion() const {
     return PortionField::decode(value_);
   }
 };
 
 
-class HLoadNamedField: public HTemplateInstruction<2> {
+class HLoadNamedField: public HTemplateInstruction<1> {
  public:
   DECLARE_INSTRUCTION_FACTORY_P2(HLoadNamedField, HValue*, HObjectAccess);
-  DECLARE_INSTRUCTION_FACTORY_P3(HLoadNamedField, HValue*, HObjectAccess,
-                                 HValue*);
 
   HValue* object() { return OperandAt(0); }
-  HValue* typecheck() {
-    ASSERT(HasTypeCheck());
-    return OperandAt(1);
-  }
-
-  bool HasTypeCheck() const { return OperandAt(0) != OperandAt(1); }
-  void ClearTypeCheck() { SetOperandAt(1, object()); }
+  bool HasTypeCheck() { return object()->IsCheckMaps(); }
+  void ClearTypeCheck() { SetOperandAt(0, object()->ActualValue()); }
   HObjectAccess access() const { return access_; }
   Representation field_representation() const {
       return access_.representation();
   }
 
   virtual bool HasEscapingOperandAt(int index) { return false; }
   virtual Representation RequiredInputRepresentation(int index) {
     if (index == 0 && access().IsExternalMemory()) {
       // object must be external in case of external memory access
       return Representation::External();
     }
     return Representation::Tagged();
   }
   virtual Range* InferRange(Zone* zone);
   virtual void PrintDataTo(StringStream* stream);
 
   DECLARE_CONCRETE_INSTRUCTION(LoadNamedField)
 
  protected:
   virtual bool DataEquals(HValue* other) {
     HLoadNamedField* b = HLoadNamedField::cast(other);
     return access_.Equals(b->access_);
   }
 
  private:
-  HLoadNamedField(HValue* object,
-                  HObjectAccess access,
-                  HValue* typecheck = NULL)
-      : access_(access) {
+  HLoadNamedField(HValue* object, HObjectAccess access) : access_(access) {
     ASSERT(object != NULL);
     SetOperandAt(0, object);
-    SetOperandAt(1, typecheck != NULL ? typecheck : object);
 
     Representation representation = access.representation();
     if (representation.IsSmi()) {
       set_type(HType::Smi());
       set_representation(representation);
     } else if (representation.IsDouble() ||
                representation.IsExternal() ||
                representation.IsInteger32()) {
       set_representation(representation);
     } else if (FLAG_track_heap_object_fields &&
@@ skipping 1152 matching lines @@
   virtual bool IsDeletable() const { return true; }
 };
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_