Revert "Refactor transitioning stores."

src/hydrogen-instructions.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_HYDROGEN_INSTRUCTIONS_H_
 #define V8_HYDROGEN_INSTRUCTIONS_H_
 
 #include "v8.h"
 
 #include "allocation.h"
@@ skipping 6638 matching lines @@
 // initialized or not.
 enum StoreFieldOrKeyedMode {
   // The entry could be either previously initialized or not.
   INITIALIZING_STORE,
   // At the time of this store it is guaranteed that the entry is already
   // initialized.
   STORE_TO_INITIALIZED_ENTRY
 };
 
 
-class HStoreNamedField V8_FINAL : public HTemplateInstruction<2> {
+class HStoreNamedField V8_FINAL : public HTemplateInstruction<3> {
  public:
   DECLARE_INSTRUCTION_FACTORY_P3(HStoreNamedField, HValue*,
                                  HObjectAccess, HValue*);
   DECLARE_INSTRUCTION_FACTORY_P4(HStoreNamedField, HValue*,
                                  HObjectAccess, HValue*, StoreFieldOrKeyedMode);
 
   DECLARE_CONCRETE_INSTRUCTION(StoreNamedField)
 
   virtual bool HasEscapingOperandAt(int index) V8_OVERRIDE {
     return index == 1;
@@ skipping 29 matching lines @@
                                          HValue* dominator) V8_OVERRIDE {
     ASSERT(side_effect == kNewSpacePromotion);
     if (!FLAG_use_write_barrier_elimination) return false;
     new_space_dominator_ = dominator;
     return false;
   }
   virtual void PrintDataTo(StringStream* stream) V8_OVERRIDE;
 
   HValue* object() const { return OperandAt(0); }
   HValue* value() const { return OperandAt(1); }
+  HValue* transition() const { return OperandAt(2); }
 
   HObjectAccess access() const { return access_; }
   HValue* new_space_dominator() const { return new_space_dominator_; }
+  bool has_transition() const { return has_transition_; }
   StoreFieldOrKeyedMode store_mode() const { return store_mode_; }
 
+  Handle<Map> transition_map() const {
+    if (has_transition()) {
+      return Handle<Map>::cast(
+          HConstant::cast(transition())->handle(Isolate::Current()));
+    } else {
+      return Handle<Map>();
+    }
+  }
+
+  void SetTransition(HConstant* transition) {
+    ASSERT(!has_transition());  // Only set once.
+    SetOperandAt(2, transition);
+    has_transition_ = true;
+  }
+
   bool NeedsWriteBarrier() {
+    ASSERT(!field_representation().IsDouble() || !has_transition());
     if (field_representation().IsDouble()) return false;
     if (field_representation().IsSmi()) return false;
     if (field_representation().IsInteger32()) return false;
     if (field_representation().IsExternal()) return false;
     return StoringValueNeedsWriteBarrier(value()) &&
         ReceiverObjectNeedsWriteBarrier(object(), value(),
                                         new_space_dominator());
   }
 
+  bool NeedsWriteBarrierForMap() {
+    return ReceiverObjectNeedsWriteBarrier(object(), transition(),
+                                           new_space_dominator());
+  }
+
   Representation field_representation() const {
     return access_.representation();
   }
 
   void UpdateValue(HValue* value) {
     SetOperandAt(1, value);
   }
 
  private:
   HStoreNamedField(HValue* obj,
                    HObjectAccess access,
                    HValue* val,
                    StoreFieldOrKeyedMode store_mode = INITIALIZING_STORE)
       : access_(access),
         new_space_dominator_(NULL),
+        has_transition_(false),
         store_mode_(store_mode) {
     // Stores to a non existing in-object property are allowed only to the
     // newly allocated objects (via HAllocate or HInnerAllocatedObject).
     ASSERT(!access.IsInobject() || access.existing_inobject_property() ||
            obj->IsAllocate() || obj->IsInnerAllocatedObject());
     SetOperandAt(0, obj);
     SetOperandAt(1, val);
+    SetOperandAt(2, obj);
     access.SetGVNFlags(this, STORE);
   }
 
   HObjectAccess access_;
   HValue* new_space_dominator_;
+  bool has_transition_ : 1;
   StoreFieldOrKeyedMode store_mode_ : 1;
 };
 
 
 class HStoreNamedGeneric V8_FINAL : public HTemplateInstruction<3> {
  public:
   DECLARE_INSTRUCTION_WITH_CONTEXT_FACTORY_P4(HStoreNamedGeneric, HValue*,
                                               Handle<String>, HValue*,
                                               StrictMode);
   HValue* object() { return OperandAt(0); }
@@ skipping 923 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_