Reland of Sampling heap profiler data structure changes

src/profiler/sampling-heap-profiler.h

Index: src/profiler/sampling-heap-profiler.h
diff --git a/src/profiler/sampling-heap-profiler.h b/src/profiler/sampling-heap-profiler.h
index 1f98bec849f80f7f068c8e903d6b6b8e190f79e2..9aee282c8aff3da185df0aaea3b732989ab92cdf 100644
--- a/src/profiler/sampling-heap-profiler.h
+++ b/src/profiler/sampling-heap-profiler.h
@@ -48,50 +48,50 @@
 
   StringsStorage* names() const { return names_; }
 
-  class FunctionInfo {
+  class AllocationNode;
+
+  struct Sample {
    public:
-    FunctionInfo(SharedFunctionInfo* shared, StringsStorage* names);
-    explicit FunctionInfo(const char* name)
-        : name_(name),
-          script_name_(""),
-          script_id_(v8::UnboundScript::kNoScriptId),
-          start_position_(0) {}
-
-    const char* get_name() const { return name_; }
-    const char* get_script_name() const { return script_name_; }
-    int get_script_id() const { return script_id_; }
-    int get_start_position() const { return start_position_; }
+    Sample(size_t size_, AllocationNode* owner_, Local<Value> local_,
+           SamplingHeapProfiler* profiler_)
+        : size(size_),
+          owner(owner_),
+          global(Global<Value>(
+              reinterpret_cast<v8::Isolate*>(profiler_->isolate_), local_)),
+          profiler(profiler_) {}
+    ~Sample() { global.Reset(); }
+    const size_t size;
+    AllocationNode* const owner;
+    Global<Value> global;
+    SamplingHeapProfiler* const profiler;
 
    private:
-    const char* const name_;
-    const char* script_name_;
-    int script_id_;
-    const int start_position_;
+    DISALLOW_COPY_AND_ASSIGN(Sample);
   };
 
-  class SampledAllocation {
+  class AllocationNode {
    public:
-    SampledAllocation(SamplingHeapProfiler* sampling_heap_profiler,
-                      Isolate* isolate, Local<Value> local, size_t size,
-                      int max_frames);
-    ~SampledAllocation() {
-      for (auto info : stack_) {
-        delete info;
+    AllocationNode(const char* const name, int script_id,
+                   const int start_position)
+        : script_id_(script_id),
+          script_position_(start_position),
+          name_(name) {}
+    ~AllocationNode() {
+      for (auto child : children_) {
+        delete child;
       }
-      global_.Reset();  // drop the reference.
     }
-    size_t get_size() const { return size_; }
-    const std::vector<FunctionInfo*>& get_stack() const { return stack_; }
 
    private:
-    static void OnWeakCallback(const WeakCallbackInfo<SampledAllocation>& data);
+    std::map<size_t, unsigned int> allocations_;
+    std::vector<AllocationNode*> children_;
+    const int script_id_;
+    const int script_position_;
+    const char* const name_;
 
-    SamplingHeapProfiler* const sampling_heap_profiler_;
-    Global<Value> global_;
-    std::vector<FunctionInfo*> stack_;
-    const size_t size_;
+    friend class SamplingHeapProfiler;
 
-    DISALLOW_COPY_AND_ASSIGN(SampledAllocation);
+    DISALLOW_COPY_AND_ASSIGN(AllocationNode);
   };
 
  private:
@@ -99,23 +99,29 @@
 
   void SampleObject(Address soon_object, size_t size);
 
+  static void OnWeakCallback(const WeakCallbackInfo<Sample>& data);
+
   // Methods that construct v8::AllocationProfile.
-  v8::AllocationProfile::Node* AddStack(
-      AllocationProfile* profile, const std::map<int, Script*>& scripts,
-      const std::vector<FunctionInfo*>& stack);
-  v8::AllocationProfile::Node* FindOrAddChildNode(
-      AllocationProfile* profile, const std::map<int, Script*>& scripts,
-      v8::AllocationProfile::Node* parent, FunctionInfo* function_info);
-  v8::AllocationProfile::Node* AllocateNode(
-      AllocationProfile* profile, const std::map<int, Script*>& scripts,
-      FunctionInfo* function_info);
+
+  // Translates the provided AllocationNode *node* returning an equivalent
+  // AllocationProfile::Node. The newly created AllocationProfile::Node is added
+  // to the provided AllocationProfile *profile*. Line numbers, column numbers,
+  // and script names are resolved using *scripts* which maps all currently
+  // loaded scripts keyed by their script id.
+  v8::AllocationProfile::Node* TranslateAllocationNode(
+      AllocationProfile* profile, SamplingHeapProfiler::AllocationNode* node,
+      const std::map<int, Script*>& scripts);
+  AllocationNode* AddStack();
+  AllocationNode* FindOrAddChildNode(AllocationNode* parent, const char* name,
+                                     int script_id, int start_position);
 
   Isolate* const isolate_;
   Heap* const heap_;
   base::SmartPointer<SamplingAllocationObserver> new_space_observer_;
   base::SmartPointer<SamplingAllocationObserver> other_spaces_observer_;
   StringsStorage* const names_;
-  std::set<SampledAllocation*> samples_;
+  AllocationNode profile_root_;
+  std::set<Sample*> samples_;
   const int stack_depth_;
 
   friend class SamplingAllocationObserver;