Remove GlobalHandles::number_of_weak_handles_ and number_of_global_object_weak_handles_

This is a preparation patch for inlining MakeWeak() and Clear().

Given that NumberOfWeakHandles() is used only by CHECK_EQ() in serialized.cc and that NumberOfGlobalObjectWeakHandles is unused, it is wasteful to keep track of number_of_weak_handles_ and number_of_global_object_weak_handles_ at every MakeWeak() and Clear(). Instead, we can count the number at the point where NumberOfWeakHandles() or NumberOfGlobalObjectWeakHandles() is called.

BUG=

Review URL: https://codereview.chromium.org/11958015
Patch from Kentaro Hara <haraken@chromium.org>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@13443 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/global-handles.cc

@@ -106,12 +106,6 @@ class GlobalHandles::Node {
 
   void Release(GlobalHandles* global_handles) {
     ASSERT(state() != FREE);
-    if (IsWeakRetainer()) {
-      global_handles->number_of_weak_handles_--;
-      if (object_->IsJSGlobalObject()) {
-        global_handles->number_of_global_object_weak_handles_--;
-      }
-    }
     set_state(FREE);
     parameter_or_next_free_.next_free = global_handles->first_free_;
     global_handles->first_free_ = this;
@@ -221,12 +215,6 @@ class GlobalHandles::Node {
                 void* parameter,
                 WeakReferenceCallback callback) {
     ASSERT(state() != FREE);
-    if (!IsWeakRetainer()) {
-      global_handles->number_of_weak_handles_++;
-      if (object_->IsJSGlobalObject()) {
-        global_handles->number_of_global_object_weak_handles_++;
-      }
-    }
     set_state(WEAK);
     set_parameter(parameter);
     callback_ = callback;
@@ -234,12 +222,6 @@ class GlobalHandles::Node {
 
   void ClearWeakness(GlobalHandles* global_handles) {
     ASSERT(state() != FREE);
-    if (IsWeakRetainer()) {
-      global_handles->number_of_weak_handles_--;
-      if (object_->IsJSGlobalObject()) {
-        global_handles->number_of_global_object_weak_handles_--;
-      }
-    }
     set_state(NORMAL);
     set_parameter(NULL);
   }
@@ -421,8 +403,6 @@ class GlobalHandles::NodeIterator {
 
 GlobalHandles::GlobalHandles(Isolate* isolate)
     : isolate_(isolate),
-      number_of_weak_handles_(0),
-      number_of_global_object_weak_handles_(0),
       number_of_global_handles_(0),
       first_block_(NULL),
       first_used_block_(NULL),
@@ -712,6 +692,29 @@ void GlobalHandles::IterateAllRootsWithClassIds(ObjectVisitor* v) {
 }
 
 
+int GlobalHandles::NumberOfWeakHandles() {
+  int count = 0;
+  for (NodeIterator it(this); !it.done(); it.Advance()) {
+    if (it.node()->IsWeakRetainer()) {
+      count++;
+    }
+  }
+  return count;
+}
+
+
+int GlobalHandles::NumberOfGlobalObjectWeakHandles() {
+  int count = 0;
+  for (NodeIterator it(this); !it.done(); it.Advance()) {
+    if (it.node()->IsWeakRetainer() &&
+        it.node()->object()->IsJSGlobalObject()) {
+      count++;
+    }
+  }
+  return count;
+}
+
+
 void GlobalHandles::RecordStats(HeapStats* stats) {
   *stats->global_handle_count = 0;
   *stats->weak_global_handle_count = 0;

src/global-handles.h

@@ -130,16 +130,14 @@ class GlobalHandles {
                 void* parameter,
                 WeakReferenceCallback callback);
 
-  // Returns the current number of weak handles.
-  int NumberOfWeakHandles() { return number_of_weak_handles_; }
-
   void RecordStats(HeapStats* stats);
 
+  // Returns the current number of weak handles.
+  int NumberOfWeakHandles();
+
   // Returns the current number of weak handles to global objects.
   // These handles are also included in NumberOfWeakHandles().
-  int NumberOfGlobalObjectWeakHandles() {
-    return number_of_global_object_weak_handles_;
-  }
+  int NumberOfGlobalObjectWeakHandles();
 
   // Returns the current number of handles to global objects.
   int NumberOfGlobalHandles() {
@@ -255,14 +253,6 @@ class GlobalHandles {
 
   Isolate* isolate_;
 
-  // Field always containing the number of weak and near-death handles.
-  int number_of_weak_handles_;
-
-  // Field always containing the number of weak and near-death handles
-  // to global objects.  These objects are also included in
-  // number_of_weak_handles_.
-  int number_of_global_object_weak_handles_;
-
   // Field always containing the number of handles to global objects.
   int number_of_global_handles_;