Reland concurrent sweeping of code space.

src/frames.cc

Index: src/frames.cc
diff --git a/src/frames.cc b/src/frames.cc
index 5f51dec2882cab9c473032d47c15bfce5d711105..0a5138eb7ae53e37a7bd1ce3e14912699020508a 100644
--- a/src/frames.cc
+++ b/src/frames.cc
@@ -1446,6 +1446,10 @@ Code* InnerPointerToCodeCache::GcSafeFindCodeForInnerPointer(
   // after the inner pointer.
   Page* page = Page::FromAddress(inner_pointer);
 
+  DCHECK(page->owner() == heap->code_space());

[jochen (gone - plz use gerrit), 2015/07/27 14:53:05]

DCHECK_EQ?

[Hannes Payer (out of office), 2015/07/27 15:04:45]

Done.

+  heap->mark_compact_collector()->SweepOrWaitUntilSweepingCompleted(
+      page, reinterpret_cast<PagedSpace*>(page->owner()));

[jochen (gone - plz use gerrit), 2015/07/27 14:53:05]

you always invoke this method with page, page->owner(). why not just pass only
page, and compute owner internally?

[Hannes Payer (out of office), 2015/07/27 15:04:45]

Done.

+
   Address addr = page->skip_list()->StartFor(inner_pointer);
 
   Address top = heap->code_space()->top();