Eliminate fake-Isolate workaround from concurrent sweeper.

runtime/vm/gc_sweeper.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/gc_sweeper.h"
 
 #include "vm/freelist.h"
 #include "vm/globals.h"
 #include "vm/heap.h"
 #include "vm/lockers.h"
@@ skipping 10 matching lines @@
   uword start = page->object_start();
   uword end = page->object_end();
   uword current = start;
 
   while (current < end) {
     intptr_t obj_size;
     RawObject* raw_obj = RawObject::FromAddr(current);
     if (raw_obj->IsMarked()) {
       // Found marked object. Clear the mark bit and update swept bytes.
       raw_obj->ClearMarkBit();
-      obj_size = raw_obj->Size();
+      obj_size = raw_obj->Size(class_table_);
       in_use = true;
     } else {
-      uword free_end = current + raw_obj->Size();
+      uword free_end = current + raw_obj->Size(class_table_);
       while (free_end < end) {
         RawObject* next_obj = RawObject::FromAddr(free_end);
         if (next_obj->IsMarked()) {
           // Reached the end of the free block.
           break;
         }
         // Expand the free block by the size of this object.
-        free_end += next_obj->Size();
+        free_end += next_obj->Size(class_table_);
       }
       obj_size = free_end - current;
       if (is_executable) {
         memset(reinterpret_cast<void*>(current), 0xcc, obj_size);
       } else {
 #if defined(DEBUG)
         memset(reinterpret_cast<void*>(current), Heap::kZapByte, obj_size);
 #endif  // DEBUG
       }
       if ((current != start) || (free_end != end)) {
@@ skipping 11 matching lines @@
 
   return in_use;
 }
 
 
 intptr_t GCSweeper::SweepLargePage(HeapPage* page) {
   intptr_t words_to_end = 0;
   RawObject* raw_obj = RawObject::FromAddr(page->object_start());
   if (raw_obj->IsMarked()) {
     raw_obj->ClearMarkBit();
-    words_to_end = (raw_obj->Size() >> kWordSizeLog2);
+    words_to_end = (raw_obj->Size(class_table_) >> kWordSizeLog2);
   }
 #ifdef DEBUG
   // String::MakeExternal and Array::MakeArray create trailing filler objects,
   // but they are always unreachable. Verify that they are not marked.
-  uword current = RawObject::ToAddr(raw_obj) + raw_obj->Size();
+  uword current = RawObject::ToAddr(raw_obj) + raw_obj->Size(class_table_);
   uword end = page->object_end();
   while (current < end) {
     RawObject* cur_obj = RawObject::FromAddr(current);
     ASSERT(!cur_obj->IsMarked());
-    intptr_t obj_size = cur_obj->Size();
+    intptr_t obj_size = cur_obj->Size(class_table_);
     memset(reinterpret_cast<void*>(current), Heap::kZapByte, obj_size);
     current += obj_size;
   }
 #endif  // DEBUG
   return words_to_end;
 }
 
 
 class SweeperTask : public ThreadPool::Task {
  public:
-  SweeperTask(Isolate* isolate,
+  SweeperTask(ClassTable* class_table,
               PageSpace* old_space,
               HeapPage* first,
               HeapPage* last,
               FreeList* freelist)
-      : task_isolate_(isolate),
+      : class_table_(class_table),
         old_space_(old_space),
         first_(first),
         last_(last),
         freelist_(freelist) {
-    ASSERT(task_isolate_ != NULL);
+    ASSERT(class_table_ != NULL);
     ASSERT(first_ != NULL);
     ASSERT(old_space_ != NULL);
     ASSERT(last_ != NULL);
     ASSERT(freelist_ != NULL);
     MonitorLocker ml(old_space_->tasks_lock());
     old_space_->set_tasks(old_space_->tasks() + 1);
     ml.Notify();
   }
 
   virtual void Run() {
-    Isolate::SetCurrent(task_isolate_);
-    GCSweeper sweeper;
+    GCSweeper sweeper(class_table_);
 
     HeapPage* page = first_;
     HeapPage* prev_page = NULL;
 
     while (page != NULL) {
       HeapPage* next_page = page->next();
       ASSERT(page->type() == HeapPage::kData);
       bool page_in_use = sweeper.SweepPage(page, freelist_, false);
       if (page_in_use) {
         prev_page = page;
       } else {
         old_space_->FreePage(page, prev_page);
       }
       {
         // Notify the mutator thread that we have added elements to the free
         // list or that more capacity is available.
         MonitorLocker ml(old_space_->tasks_lock());
         ml.Notify();
       }
       if (page == last_) break;
       page = next_page;
     }
     // This sweeper task is done. Notify the original isolate.
     {
       MonitorLocker ml(old_space_->tasks_lock());
       old_space_->set_tasks(old_space_->tasks() - 1);
       ml.Notify();
     }
-    Isolate::SetCurrent(NULL);
-    delete task_isolate_;
   }
 
  private:
-  Isolate* task_isolate_;
+  ClassTable* class_table_;
   PageSpace* old_space_;
   HeapPage* first_;
   HeapPage* last_;
   FreeList* freelist_;
 };
 
 
 void GCSweeper::SweepConcurrent(Isolate* isolate,
                                 HeapPage* first,
                                 HeapPage* last,
                                 FreeList* freelist) {
   SweeperTask* task =
-      new SweeperTask(isolate->ShallowCopy(),
+      new SweeperTask(isolate->class_table(),
                       isolate->heap()->old_space(),
                       first, last,
                       freelist);
   ThreadPool* pool = Dart::thread_pool();
   pool->Run(task);
 }
 
 }  // namespace dart