Heap profiler: account primitive string objects as being constructed using 'String'.

src/heap.cc

 // Copyright 2009 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 3531 matching lines @@
 #ifdef ENABLE_LOGGING_AND_PROFILING
 namespace {
 
 // JSConstructorProfile is responsible for gathering and logging
 // "constructor profile" of JS object allocated on heap.
 // It is run during garbage collection cycle, thus it doesn't need
 // to use handles.
 class JSConstructorProfile BASE_EMBEDDED {
  public:
   JSConstructorProfile() : zscope_(DELETE_ON_EXIT) {}
-  void CollectStats(JSObject* obj);
+  void CollectStats(HeapObject* obj);
   void PrintStats();
   // Used by ZoneSplayTree::ForEach.
   void Call(String* name, const NumberAndSizeInfo& number_and_size);
  private:
   struct TreeConfig {
     typedef String* Key;
     typedef NumberAndSizeInfo Value;
     static const Key kNoKey;
     static const Value kNoValue;
     // Strings are unique, so it is sufficient to compare their pointers.
@@ skipping 24 matching lines @@
   }
   if (FixedArray::cast(obj->elements())->length() != 0) {
     size += obj->elements()->Size();
   }
   return size;
 }
 
 
 void JSConstructorProfile::Call(String* name,
                                 const NumberAndSizeInfo& number_and_size) {
-  SmartPointer<char> s_name;
-  if (name != NULL) {
-    s_name = name->ToCString(DISALLOW_NULLS, ROBUST_STRING_TRAVERSAL);
-  }
+  ASSERT(name != NULL);
+  SmartPointer<char> s_name(
+      name->ToCString(DISALLOW_NULLS, ROBUST_STRING_TRAVERSAL));
   LOG(HeapSampleJSConstructorEvent(*s_name,
                                    number_and_size.number(),
                                    number_and_size.bytes()));
 }
 
 
-void JSConstructorProfile::CollectStats(JSObject* obj) {
-  String* constructor_func = NULL;
-  if (obj->map()->constructor()->IsJSFunction()) {
-    JSFunction* constructor = JSFunction::cast(obj->map()->constructor());
-    SharedFunctionInfo* sfi = constructor->shared();
-    String* name = String::cast(sfi->name());
-    constructor_func = name->length() > 0 ? name : sfi->inferred_name();
-  } else if (obj->IsJSFunction()) {
-    constructor_func = Heap::function_class_symbol();
+void JSConstructorProfile::CollectStats(HeapObject* obj) {
+  String* constructor = NULL;
+  int size;
+  if (obj->IsString()) {
+    constructor = Heap::String_symbol();
+    size = obj->Size();
+  } else if (obj->IsJSObject()) {
+    JSObject* js_obj = JSObject::cast(obj);
+    constructor = js_obj->constructor_name();
+    size = CalculateJSObjectNetworkSize(js_obj);
+  } else {
+    return;
   }
+
   JSObjectsInfoTree::Locator loc;
-  if (!js_objects_info_tree_.Find(constructor_func, &loc)) {
-    js_objects_info_tree_.Insert(constructor_func, &loc);
+  if (!js_objects_info_tree_.Find(constructor, &loc)) {
+    js_objects_info_tree_.Insert(constructor, &loc);
   }
   NumberAndSizeInfo number_and_size = loc.value();
   number_and_size.increment_number(1);
-  number_and_size.increment_bytes(CalculateJSObjectNetworkSize(obj));
+  number_and_size.increment_bytes(size);
   loc.set_value(number_and_size);
 }
 
 
 void JSConstructorProfile::PrintStats() {
   js_objects_info_tree_.ForEach(this);
 }
 
 }  // namespace
 #endif
@@ skipping 21 matching lines @@
   HistogramInfo info[LAST_TYPE+1];
 #define DEF_TYPE_NAME(name) info[name].set_name(#name);
   INSTANCE_TYPE_LIST(DEF_TYPE_NAME)
 #undef DEF_TYPE_NAME
 
   JSConstructorProfile js_cons_profile;
   HeapIterator iterator;
   while (iterator.has_next()) {
     HeapObject* obj = iterator.next();
     CollectStats(obj, info);
-    if (obj->IsJSObject()) {
-      js_cons_profile.CollectStats(JSObject::cast(obj));
-    }
+    js_cons_profile.CollectStats(obj);
   }
 
   // Lump all the string types together.
   int string_number = 0;
   int string_bytes = 0;
 #define INCREMENT_SIZE(type, size, name, camel_name)   \
     string_number += info[type].number();              \
     string_bytes += info[type].bytes();
   STRING_TYPE_LIST(INCREMENT_SIZE)
 #undef INCREMENT_SIZE
@@ skipping 315 matching lines @@
   for (int i = 0; i < kNumberOfCaches; i++) {
     if (caches_[i] != NULL) {
       delete caches_[i];
       caches_[i] = NULL;
     }
   }
 }
 
 
 } }  // namespace v8::internal