Fix incremental marking to be off during heap snapshots.

src/heap.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 639 matching lines @@
       next_gc_likely_to_collect_more =
           PerformGarbageCollection(collector, &tracer);
     }
 
     ASSERT(collector == SCAVENGER || incremental_marking()->IsStopped());
 
     // This can do debug callbacks and restart incremental marking.
     GarbageCollectionEpilogue();
   }
 
-  if (incremental_marking()->IsStopped()) {
-    if (incremental_marking()->WorthActivating() && NextGCIsLikelyToBeFull()) {
-      incremental_marking()->Start();
-    }
+  // Start incremental marking for the next cycle. The heap snapshot
+  // generator needs incremental marking to stay off after it aborted.
+  if (!mark_compact_collector()->abort_incremental_marking_ &&

[Toon Verwaest, 2012/11/27 12:07:26]

Please make a protected accessor for abort_incremental_marking_;, and maybe give
it a name that describes that incremental marking should not be turned on again.

[Michael Starzinger, 2012/11/27 13:18:11]

Done.

+      incremental_marking()->IsStopped() &&
+      incremental_marking()->WorthActivating() &&
+      NextGCIsLikelyToBeFull()) {
+    incremental_marking()->Start();
   }
 
   return next_gc_likely_to_collect_more;
 }
 
 
 void Heap::PerformScavenge() {
   GCTracer tracer(this, NULL, NULL);
   if (incremental_marking()->IsStopped()) {
     PerformGarbageCollection(SCAVENGER, &tracer);
@@ skipping 6655 matching lines @@
       static_cast<int>(object_sizes_last_time_[index]));
   FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(ADJUST_LAST_TIME_OBJECT_COUNT)
 #undef ADJUST_LAST_TIME_OBJECT_COUNT
 
   memcpy(object_counts_last_time_, object_counts_, sizeof(object_counts_));
   memcpy(object_sizes_last_time_, object_sizes_, sizeof(object_sizes_));
   ClearObjectStats();
 }
 
 } }  // namespace v8::internal