Safepointing in GC

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"
 #include "vm/pages.h"
 #include "vm/thread_pool.h"
+#include "vm/thread_registry.h"
 
 namespace dart {
 
 bool GCSweeper::SweepPage(HeapPage* page, FreeList* freelist, bool locked) {
   // Keep track whether this page is still in use.
   bool in_use = false;
 
   bool is_executable = (page->type() == HeapPage::kExecutable);
   uword start = page->object_start();
   uword end = page->object_end();
@@ skipping 90 matching lines @@
   }
 
   virtual void Run() {
     Thread::EnterIsolateAsHelper(task_isolate_);
     GCSweeper sweeper;
 
     HeapPage* page = first_;
     HeapPage* prev_page = NULL;
 
     while (page != NULL) {
+      task_isolate_->thread_registry()->CheckSafepoint();
       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
@@ skipping 30 matching lines @@
   SweeperTask* task =
       new SweeperTask(isolate,
                       isolate->heap()->old_space(),
                       first, last,
                       freelist);
   ThreadPool* pool = Dart::thread_pool();
   pool->Run(task);
 }
 
 }  // namespace dart