Author: [EMAIL PROTECTED]
Date: Thu Dec 11 03:20:04 2008
New Revision: 965
Modified:
branches/bleeding_edge/include/v8.h
branches/bleeding_edge/src/api.cc
branches/bleeding_edge/src/global-handles.cc
branches/bleeding_edge/src/global-handles.h
branches/bleeding_edge/src/mark-compact.cc
branches/bleeding_edge/test/cctest/test-mark-compact.cc
Log:
Improve mark-compact object grouping interface.
The main goal was to improve O(n^2) behavior when there are many object
groups. The old API required the grouping to be done on the v8 side, along
with a linear search. The new interface requires the caller to do the
grouping, passing V8 entire groups at a time. This removes the group id
concept on the v8 side.
- Changed AddObjectToGroup to AddObjectGroup.
- Removed the group id concept from the V8 side.
- Remove a static constructor while I'm here, lazily initialize
the object groups list.
- Cleaned up return by non-const references to return pointers.
Review URL: http://codereview.chromium.org/13341
Modified: branches/bleeding_edge/include/v8.h
==============================================================================
--- branches/bleeding_edge/include/v8.h (original)
+++ branches/bleeding_edge/include/v8.h Thu Dec 11 03:20:04 2008
@@ -1967,10 +1967,10 @@
* object in the group is alive, all objects in the group are alive.
* After each garbage collection, object groups are removed. It is
* intended to be used in the before-garbage-collection callback
- * function for istance to simulate DOM tree connections among JS
+ * function, for instance to simulate DOM tree connections among JS
* wrapper objects.
*/
- static void AddObjectToGroup(void* id, Persistent<Object> obj);
+ static void AddObjectGroup(Persistent<Value>* objects, size_t length);
/**
* Initializes from snapshot if possible. Otherwise, attempts to
Modified: branches/bleeding_edge/src/api.cc
==============================================================================
--- branches/bleeding_edge/src/api.cc (original)
+++ branches/bleeding_edge/src/api.cc Thu Dec 11 03:20:04 2008
@@ -2641,9 +2641,10 @@
}
-void V8::AddObjectToGroup(void* group_id, Persistent<Object> obj) {
- if (IsDeadCheck("v8::V8::AddObjectToGroup()")) return;
- i::GlobalHandles::AddToGroup(group_id,
reinterpret_cast<i::Object**>(*obj));
+void V8::AddObjectGroup(Persistent<Value>* objects, size_t length) {
+ if (IsDeadCheck("v8::V8::AddObjectGroup()")) return;
+ STATIC_ASSERT(sizeof(Persistent<Value>) == sizeof(i::Object**));
+ i::GlobalHandles::AddGroup(reinterpret_cast<i::Object***>(objects),
length);
}
Modified: branches/bleeding_edge/src/global-handles.cc
==============================================================================
--- branches/bleeding_edge/src/global-handles.cc (original)
+++ branches/bleeding_edge/src/global-handles.cc Thu Dec 11 03:20:04 2008
@@ -352,29 +352,26 @@
#endif
-List<ObjectGroup*> GlobalHandles::object_groups_(4);
-
-void GlobalHandles::AddToGroup(void* id, Object** handle) {
- for (int i = 0; i < object_groups_.length(); i++) {
- ObjectGroup* entry = object_groups_[i];
- if (entry->id_ == id) {
- entry->objects_.Add(handle);
- return;
- }
- }
+List<ObjectGroup*>* GlobalHandles::ObjectGroups() {
+ // Lazily initialize the list to avoid startup time static constructors.
+ static List<ObjectGroup*> groups(4);
+ return &groups;
+}
- // not found
- ObjectGroup* new_entry = new ObjectGroup(id);
- new_entry->objects_.Add(handle);
- object_groups_.Add(new_entry);
+void GlobalHandles::AddGroup(Object*** handles, size_t length) {
+ ObjectGroup* new_entry = new ObjectGroup(length);
+ for (size_t i = 0; i < length; ++i)
+ new_entry->objects_.Add(handles[i]);
+ ObjectGroups()->Add(new_entry);
}
void GlobalHandles::RemoveObjectGroups() {
- for (int i = 0; i< object_groups_.length(); i++) {
- delete object_groups_[i];
+ List<ObjectGroup*>* object_groups = ObjectGroups();
+ for (int i = 0; i< object_groups->length(); i++) {
+ delete object_groups->at(i);
}
- object_groups_.Clear();
+ object_groups->Clear();
}
Modified: branches/bleeding_edge/src/global-handles.h
==============================================================================
--- branches/bleeding_edge/src/global-handles.h (original)
+++ branches/bleeding_edge/src/global-handles.h Thu Dec 11 03:20:04 2008
@@ -41,15 +41,14 @@
// Callback function on handling weak global handles.
// typedef bool (*WeakSlotCallback)(Object** pointer);
-// An object group is indexed by an id. An object group is treated like
-// a single JS object: if one of object in the group is alive,
-// all objects in the same group are considered alive.
+// An object group is treated like a single JS object: if one of object in
+// the group is alive, all objects in the same group are considered alive.
// An object group is used to simulate object relationship in a DOM tree.
class ObjectGroup : public Malloced {
public:
- explicit ObjectGroup(void* id) : id_(id), objects_(4) {}
+ ObjectGroup() : objects_(4) {}
+ explicit ObjectGroup(size_t capacity) : objects_(capacity) {}
- void* id_;
List<Object**> objects_;
};
@@ -102,15 +101,13 @@
// Mark the weak pointers based on the callback.
static void MarkWeakRoots(WeakSlotCallback f);
- // Add an object to a group indexed by an id.
+ // Add an object group.
// Should only used in GC callback function before a collection.
// All groups are destroyed after a mark-compact collection.
- static void AddToGroup(void* id, Object** location);
+ static void AddGroup(Object*** handles, size_t length);
// Returns the object groups.
- static List<ObjectGroup*>& ObjectGroups() {
- return object_groups_;
- }
+ static List<ObjectGroup*>* ObjectGroups();
// Remove bags, this should only happen after GC.
static void RemoveObjectGroups();
@@ -143,9 +140,6 @@
static Node* first_free_;
static Node* first_free() { return first_free_; }
static void set_first_free(Node* value) { first_free_ = value; }
-
- // A list of object groups.
- static List<ObjectGroup*> object_groups_;
};
Modified: branches/bleeding_edge/src/mark-compact.cc
==============================================================================
--- branches/bleeding_edge/src/mark-compact.cc (original)
+++ branches/bleeding_edge/src/mark-compact.cc Thu Dec 11 03:20:04 2008
@@ -564,10 +564,10 @@
void MarkCompactCollector::MarkObjectGroups() {
- List<ObjectGroup*>& object_groups = GlobalHandles::ObjectGroups();
+ List<ObjectGroup*>* object_groups = GlobalHandles::ObjectGroups();
- for (int i = 0; i < object_groups.length(); i++) {
- ObjectGroup* entry = object_groups[i];
+ for (int i = 0; i < object_groups->length(); i++) {
+ ObjectGroup* entry = object_groups->at(i);
if (entry == NULL) continue;
List<Object**>& objects = entry->objects_;
@@ -591,8 +591,8 @@
}
// Once the entire group has been colored gray, set the object group
// to NULL so it won't be processed again.
- delete object_groups[i];
- object_groups[i] = NULL;
+ delete object_groups->at(i);
+ object_groups->at(i) = NULL;
}
}
Modified: branches/bleeding_edge/test/cctest/test-mark-compact.cc
==============================================================================
--- branches/bleeding_edge/test/cctest/test-mark-compact.cc (original)
+++ branches/bleeding_edge/test/cctest/test-mark-compact.cc Thu Dec 11
03:20:04 2008
@@ -282,10 +282,12 @@
Handle<FixedArray>::cast(g1s2)->set(0, *g2s2);
Handle<FixedArray>::cast(g2s1)->set(0, *g1s1);
- GlobalHandles::AddToGroup(reinterpret_cast<void*>(1), g1s1.location());
- GlobalHandles::AddToGroup(reinterpret_cast<void*>(1), g1s2.location());
- GlobalHandles::AddToGroup(reinterpret_cast<void*>(2), g2s1.location());
- GlobalHandles::AddToGroup(reinterpret_cast<void*>(2), g2s2.location());
+ {
+ Object** g1_objects[] = { g1s1.location(), g1s2.location() };
+ Object** g2_objects[] = { g2s1.location(), g2s2.location() };
+ GlobalHandles::AddGroup(g1_objects, 2);
+ GlobalHandles::AddGroup(g2_objects, 2);
+ }
// Do a full GC
CHECK(Heap::CollectGarbage(0, OLD_POINTER_SPACE));
@@ -298,10 +300,12 @@
&WeakPointerCallback);
// Groups are deleted, rebuild groups.
- GlobalHandles::AddToGroup(reinterpret_cast<void*>(1), g1s1.location());
- GlobalHandles::AddToGroup(reinterpret_cast<void*>(1), g1s2.location());
- GlobalHandles::AddToGroup(reinterpret_cast<void*>(2), g2s1.location());
- GlobalHandles::AddToGroup(reinterpret_cast<void*>(2), g2s2.location());
+ {
+ Object** g1_objects[] = { g1s1.location(), g1s2.location() };
+ Object** g2_objects[] = { g2s1.location(), g2s2.location() };
+ GlobalHandles::AddGroup(g1_objects, 2);
+ GlobalHandles::AddGroup(g2_objects, 2);
+ }
CHECK(Heap::CollectGarbage(0, OLD_POINTER_SPACE));
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