Use an enum for indicating the component of an AccessorPair instead of a boolean flag.

In addition, this CL introduces a tiny new helper, which will come in handy later,
plus some minor cleanup.

Review URL: https://chromiumcodereview.appspot.com/9600013

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10918 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/objects.cc

@@ -4367,7 +4367,7 @@ void JSObject::LookupCallback(String* name, LookupResult* result) {
 static bool UpdateGetterSetterInDictionary(
     SeededNumberDictionary* dictionary,
     uint32_t index,
-    bool is_getter,
+    AccessorComponent component,
     Object* fun,
     PropertyAttributes attributes) {
   int entry = dictionary->FindEntry(index);
@@ -4381,7 +4381,7 @@ static bool UpdateGetterSetterInDictionary(
         dictionary->DetailsAtPut(entry,
                                  PropertyDetails(attributes, CALLBACKS, index));
       }
-      AccessorPair::cast(result)->set(is_getter, fun);
+      AccessorPair::cast(result)->set(component, fun);
       return true;
     }
   }
@@ -4390,7 +4390,7 @@ static bool UpdateGetterSetterInDictionary(
 
 
 MaybeObject* JSObject::DefineElementAccessor(uint32_t index,
-                                             bool is_getter,
+                                             AccessorComponent component,
                                              Object* fun,
                                              PropertyAttributes attributes) {
   switch (GetElementsKind()) {
@@ -4412,7 +4412,7 @@ MaybeObject* JSObject::DefineElementAccessor(uint32_t index,
     case DICTIONARY_ELEMENTS:
       if (UpdateGetterSetterInDictionary(element_dictionary(),
                                          index,
-                                         is_getter,
+                                         component,
                                          fun,
                                          attributes)) {
         return GetHeap()->undefined_value();
@@ -4433,7 +4433,7 @@ MaybeObject* JSObject::DefineElementAccessor(uint32_t index,
               SeededNumberDictionary::cast(arguments);
           if (UpdateGetterSetterInDictionary(dictionary,
                                              index,
-                                             is_getter,
+                                             component,
                                              fun,
                                              attributes)) {
             return GetHeap()->undefined_value();
@@ -4448,14 +4448,14 @@ MaybeObject* JSObject::DefineElementAccessor(uint32_t index,
   { MaybeObject* maybe_accessors = GetHeap()->AllocateAccessorPair();
     if (!maybe_accessors->To(&accessors)) return maybe_accessors;
   }
-  accessors->set(is_getter, fun);
+  accessors->set(component, fun);
 
   return SetElementCallback(index, accessors, attributes);
 }
 
 
 MaybeObject* JSObject::DefinePropertyAccessor(String* name,
-                                              bool is_getter,
+                                              AccessorComponent component,
                                               Object* fun,
                                               PropertyAttributes attributes) {
   // Lookup the name.
@@ -4473,7 +4473,7 @@ MaybeObject* JSObject::DefinePropertyAccessor(String* name,
               AccessorPair::cast(obj)->CopyWithoutTransitions();
           if (!maybe_copy->To(&copy)) return maybe_copy;
         }
-        copy->set(is_getter, fun);
+        copy->set(component, fun);
         // Use set to update attributes.
         return SetPropertyCallback(name, copy, attributes);
       }
@@ -4484,7 +4484,7 @@ MaybeObject* JSObject::DefinePropertyAccessor(String* name,
   { MaybeObject* maybe_accessors = GetHeap()->AllocateAccessorPair();
     if (!maybe_accessors->To(&accessors)) return maybe_accessors;
   }
-  accessors->set(is_getter, fun);
+  accessors->set(component, fun);
 
   return SetPropertyCallback(name, accessors, attributes);
 }
@@ -4593,7 +4593,7 @@ MaybeObject* JSObject::SetPropertyCallback(String* name,
 }
 
 MaybeObject* JSObject::DefineAccessor(String* name,
-                                      bool is_getter,
+                                      AccessorComponent component,
                                       Object* fun,
                                       PropertyAttributes attributes) {
   ASSERT(fun->IsSpecFunction() || fun->IsUndefined());
@@ -4609,7 +4609,7 @@ MaybeObject* JSObject::DefineAccessor(String* name,
     Object* proto = GetPrototype();
     if (proto->IsNull()) return this;
     ASSERT(proto->IsJSGlobalObject());
-    return JSObject::cast(proto)->DefineAccessor(name, is_getter,
+    return JSObject::cast(proto)->DefineAccessor(name, component,
                                                  fun, attributes);
   }
 
@@ -4624,8 +4624,8 @@ MaybeObject* JSObject::DefineAccessor(String* name,
 
   uint32_t index = 0;
   return name->AsArrayIndex(&index) ?
-      DefineElementAccessor(index, is_getter, fun, attributes) :
-      DefinePropertyAccessor(name, is_getter, fun, attributes);
+      DefineElementAccessor(index, component, fun, attributes) :
+      DefinePropertyAccessor(name, component, fun, attributes);
 }
 
 
@@ -4711,7 +4711,7 @@ MaybeObject* JSObject::DefineAccessor(AccessorInfo* info) {
 }
 
 
-Object* JSObject::LookupAccessor(String* name, bool is_getter) {
+Object* JSObject::LookupAccessor(String* name, AccessorComponent component) {
   Heap* heap = GetHeap();
 
   // Make sure that the top context does not change when doing callbacks or
@@ -4737,12 +4737,9 @@ Object* JSObject::LookupAccessor(String* name, bool is_getter) {
         int entry = dictionary->FindEntry(index);
         if (entry != SeededNumberDictionary::kNotFound) {
           Object* element = dictionary->ValueAt(entry);
-          PropertyDetails details = dictionary->DetailsAt(entry);
-          if (details.type() == CALLBACKS) {
-            if (element->IsAccessorPair()) {
-              AccessorPair* accessors = AccessorPair::cast(element);
-              return is_getter ? accessors->getter() : accessors->setter();
-            }
+          if (dictionary->DetailsAt(entry).type() == CALLBACKS &&
+              element->IsAccessorPair()) {
+            return AccessorPair::cast(element)->get(component);
           }
         }
       }
@@ -4758,8 +4755,7 @@ Object* JSObject::LookupAccessor(String* name, bool is_getter) {
         if (result.type() == CALLBACKS) {
           Object* obj = result.GetCallbackObject();
           if (obj->IsAccessorPair()) {
-            AccessorPair* accessors = AccessorPair::cast(obj);
-            return is_getter ? accessors->getter() : accessors->setter();
+            return AccessorPair::cast(obj)->get(component);
           }
         }
       }

src/objects.h

@@ -1360,6 +1360,13 @@ enum SetPropertyMode {
 };
 
 
+// Indicator for one component of an AccessorPair.
+enum AccessorComponent {
+  ACCESSOR_GETTER,
+  ACCESSOR_SETTER
+};
+
+
 // JSReceiver includes types on which properties can be defined, i.e.,
 // JSObject and JSProxy.
 class JSReceiver: public HeapObject {
@@ -1612,10 +1619,10 @@ class JSObject: public JSReceiver {
       bool continue_search);
 
   MUST_USE_RESULT MaybeObject* DefineAccessor(String* name,
-                                              bool is_getter,
+                                              AccessorComponent component,
                                               Object* fun,
                                               PropertyAttributes attributes);
-  Object* LookupAccessor(String* name, bool is_getter);
+  Object* LookupAccessor(String* name, AccessorComponent component);
 
   MUST_USE_RESULT MaybeObject* DefineAccessor(AccessorInfo* info);
 
@@ -2166,12 +2173,12 @@ class JSObject: public JSReceiver {
       PropertyAttributes attributes);
   MUST_USE_RESULT MaybeObject* DefineElementAccessor(
       uint32_t index,
-      bool is_getter,
+      AccessorComponent component,
       Object* fun,
       PropertyAttributes attributes);
   MUST_USE_RESULT MaybeObject* DefinePropertyAccessor(
       String* name,
-      bool is_getter,
+      AccessorComponent component,
       Object* fun,
       PropertyAttributes attributes);
   void LookupInDescriptor(String* name, LookupResult* result);
@@ -7927,9 +7934,14 @@ class AccessorPair: public Struct {
 
   MUST_USE_RESULT MaybeObject* CopyWithoutTransitions();
 
-  // TODO(svenpanne) Evil temporary helper, will vanish soon...
-  void set(bool modify_getter, Object* value) {
-    if (modify_getter) {
+  Object* get(AccessorComponent component) {
+    ASSERT(component == ACCESSOR_GETTER || component == ACCESSOR_SETTER);
+    return (component == ACCESSOR_GETTER) ? getter() : setter();
+  }
+
+  void set(AccessorComponent component, Object* value) {
+    ASSERT(component == ACCESSOR_GETTER || component == ACCESSOR_SETTER);
+    if (component == ACCESSOR_GETTER) {
       set_getter(value);
     } else {
       set_setter(value);

src/runtime.cc

@@ -4318,7 +4318,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_DefineOrRedefineAccessorProperty) {
   HandleScope scope(isolate);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, obj, 0);
   CONVERT_ARG_CHECKED(String, name, 1);
-  CONVERT_SMI_ARG_CHECKED(flag_setter, 2);
+  CONVERT_SMI_ARG_CHECKED(flag, 2);
   Object* fun = args[3];
   CONVERT_SMI_ARG_CHECKED(unchecked, 4);
 
@@ -4327,7 +4327,8 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_DefineOrRedefineAccessorProperty) {
 
   RUNTIME_ASSERT(!obj->IsNull());
   RUNTIME_ASSERT(fun->IsSpecFunction() || fun->IsUndefined());
-  return obj->DefineAccessor(name, flag_setter == 0, fun, attr);
+  AccessorComponent component = flag == 0 ? ACCESSOR_GETTER : ACCESSOR_SETTER;
+  return obj->DefineAccessor(name, component, fun, attr);
 }
 
 // Implements part of 8.12.9 DefineOwnProperty.
@@ -10292,7 +10293,8 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_LookupAccessor) {
   CONVERT_ARG_CHECKED(JSObject, obj, 0);
   CONVERT_ARG_CHECKED(String, name, 1);
   CONVERT_SMI_ARG_CHECKED(flag, 2);
-  return obj->LookupAccessor(name, flag == 0);
+  AccessorComponent component = flag == 0 ? ACCESSOR_GETTER : ACCESSOR_SETTER;
+  return obj->LookupAccessor(name, component);
 }