HStoreNamedField for Smis optimized for x64

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 6494 matching lines @@
   HLoadKeyedGeneric(HValue* context, HValue* obj, HValue* key) {
     set_representation(Representation::Tagged());
     SetOperandAt(0, obj);
     SetOperandAt(1, key);
     SetOperandAt(2, context);
     SetAllSideEffects();
   }
 };
 
 
+// Indicates whether the store is a store to an entry that was previously
+// initialized or not.
+enum StoreFieldOrKeyedMode {
+  INITIALIZING_STORE,
+  STORE_TO_INITIALIZED_ENTRY
+};
+
+
 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;
   }
   virtual bool HasOutOfBoundsAccess(int size) V8_OVERRIDE {
     return !access().IsInobject() || access().offset() >= size;
   }
   virtual Representation RequiredInputRepresentation(int index) V8_OVERRIDE {
     if (index == 0 && access().IsExternalMemory()) {
       // object must be external in case of external memory access
       return Representation::External();
     } else if (index == 1) {
       if (field_representation().IsInteger8() ||
           field_representation().IsUInteger8() ||
           field_representation().IsInteger16() ||
           field_representation().IsUInteger16() ||
           field_representation().IsInteger32()) {
         return Representation::Integer32();
-      } else if (field_representation().IsDouble() ||
-                 field_representation().IsSmi()) {
+      } else if (field_representation().IsDouble()) {
+        return field_representation();
+      } else if (field_representation().IsSmi()) {
+        if (SmiValuesAre32Bits() && store_mode_ == STORE_TO_INITIALIZED_ENTRY) {
+          return Representation::Integer32();
+        }
         return field_representation();
       } else if (field_representation().IsExternal()) {
         return Representation::External();
       }
     }
     return Representation::Tagged();
   }
   virtual void HandleSideEffectDominator(GVNFlag side_effect,
                                          HValue* dominator) V8_OVERRIDE {
     ASSERT(side_effect == kChangesNewSpacePromotion);
     new_space_dominator_ = dominator;
   }
   virtual void PrintDataTo(StringStream* stream) V8_OVERRIDE;
 
   void SkipWriteBarrier() { write_barrier_mode_ = SKIP_WRITE_BARRIER; }
   bool IsSkipWriteBarrier() const {
     return write_barrier_mode_ == SKIP_WRITE_BARRIER;
   }
 
   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>();
     }
   }
 
@@ skipping 30 matching lines @@
     return access_.representation();
   }
 
   void UpdateValue(HValue* value) {
     SetOperandAt(1, value);
   }
 
  private:
   HStoreNamedField(HValue* obj,
                    HObjectAccess access,
-                   HValue* val)
+                   HValue* val,
+                   StoreFieldOrKeyedMode store_mode = INITIALIZING_STORE)
       : access_(access),
         new_space_dominator_(NULL),
         write_barrier_mode_(UPDATE_WRITE_BARRIER),
-        has_transition_(false) {
+        has_transition_(false),
+        store_mode_(store_mode) {
     SetOperandAt(0, obj);
     SetOperandAt(1, val);
     SetOperandAt(2, obj);
     access.SetGVNFlags(this, true);
   }
 
   HObjectAccess access_;
   HValue* new_space_dominator_;
   WriteBarrierMode write_barrier_mode_ : 1;
   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*,
                                               StrictModeFlag);
   HValue* object() { return OperandAt(0); }
   HValue* value() { return OperandAt(1); }
@@ skipping 851 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_