Allocate new AccessorPairs with holes instead of undefined.

This is essential for the upcoming map sharing with accessors, and we aleady
have enough machinery to handle the holes now. Furthermore, use "To" template in
2 nearby functions, and made naming a bit more consistent.

In a nutshell: This CL should have no visible effect at all at the moment.
Famous last words...

Review URL: https://chromiumcodereview.appspot.com/9594013

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10919 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/heap.cc

@@ -1909,11 +1909,10 @@ MaybeObject* Heap::AllocateMap(InstanceType instance_type,
 
 
 MaybeObject* Heap::AllocateCodeCache() {
-  Object* result;
-  { MaybeObject* maybe_result = AllocateStruct(CODE_CACHE_TYPE);
-    if (!maybe_result->ToObject(&result)) return maybe_result;
+  CodeCache* code_cache;
+  { MaybeObject* maybe_code_cache = AllocateStruct(CODE_CACHE_TYPE);
+    if (!maybe_code_cache->To(&code_cache)) return maybe_code_cache;
   }
-  CodeCache* code_cache = CodeCache::cast(result);
   code_cache->set_default_cache(empty_fixed_array(), SKIP_WRITE_BARRIER);
   code_cache->set_normal_type_cache(undefined_value(), SKIP_WRITE_BARRIER);
   return code_cache;
@@ -1926,22 +1925,20 @@ MaybeObject* Heap::AllocatePolymorphicCodeCache() {
 
 
 MaybeObject* Heap::AllocateAccessorPair() {
-  Object* result;
-  { MaybeObject* maybe_result = AllocateStruct(ACCESSOR_PAIR_TYPE);
-    if (!maybe_result->ToObject(&result)) return maybe_result;
+  AccessorPair* accessors;
+  { MaybeObject* maybe_accessors = AllocateStruct(ACCESSOR_PAIR_TYPE);
+    if (!maybe_accessors->To(&accessors)) return maybe_accessors;
   }
-  AccessorPair* accessors = AccessorPair::cast(result);
-  // Later we will have to distinguish between undefined and the hole...
-  // accessors->set_getter(the_hole_value(), SKIP_WRITE_BARRIER);
-  // accessors->set_setter(the_hole_value(), SKIP_WRITE_BARRIER);
+  accessors->set_getter(the_hole_value(), SKIP_WRITE_BARRIER);
+  accessors->set_setter(the_hole_value(), SKIP_WRITE_BARRIER);
   return accessors;
 }
 
 
 MaybeObject* Heap::AllocateTypeFeedbackInfo() {
   TypeFeedbackInfo* info;
-  { MaybeObject* maybe_result = AllocateStruct(TYPE_FEEDBACK_INFO_TYPE);
-    if (!maybe_result->To(&info)) return maybe_result;
+  { MaybeObject* maybe_info = AllocateStruct(TYPE_FEEDBACK_INFO_TYPE);
+    if (!maybe_info->To(&info)) return maybe_info;
   }
   info->set_ic_total_count(0);
   info->set_ic_with_typeinfo_count(0);
@@ -1953,8 +1950,8 @@ MaybeObject* Heap::AllocateTypeFeedbackInfo() {
 
 MaybeObject* Heap::AllocateAliasedArgumentsEntry(int aliased_context_slot) {
   AliasedArgumentsEntry* entry;
-  { MaybeObject* maybe_result = AllocateStruct(ALIASED_ARGUMENTS_ENTRY_TYPE);
-    if (!maybe_result->To(&entry)) return maybe_result;
+  { MaybeObject* maybe_entry = AllocateStruct(ALIASED_ARGUMENTS_ENTRY_TYPE);
+    if (!maybe_entry->To(&entry)) return maybe_entry;
   }
   entry->set_aliased_context_slot(aliased_context_slot);
   return entry;