Old space cannot be assumed to be iterable between GCs, even if swept precisely.

This is because allocation folding can cause uninitialized and hence uniterable fragments. Trying to inspect them causes SizeFromMap() crashes.

R=hpayer@chromium.org

Review URL: https://codereview.chromium.org/467693002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23084 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/heap/mark-compact.cc b/src/heap/mark-compact.cc
index 4a11d3b082273cb5c2bfae0ed112e85315797825..abb4e1beb8e7e51936657e70d14dec33649a7faf 100644 (file)
--- a/src/heap/mark-compact.cc
+++ b/src/heap/mark-compact.cc
@@ -2009,16 +2009,11 @@ int MarkCompactCollector::DiscoverAndEvacuateBlackObjectsOnPage(
 
 static void DiscoverGreyObjectsInSpace(Heap* heap, MarkingDeque* marking_deque,
                                        PagedSpace* space) {
-  if (space->swept_precisely()) {
-    HeapObjectIterator it(space);
-    DiscoverGreyObjectsWithIterator(heap, marking_deque, &it);
-  } else {
-    PageIterator it(space);
-    while (it.has_next()) {
-      Page* p = it.next();
-      DiscoverGreyObjectsOnPage(marking_deque, p);
-      if (marking_deque->IsFull()) return;
-    }
+  PageIterator it(space);
+  while (it.has_next()) {
+    Page* p = it.next();
+    DiscoverGreyObjectsOnPage(marking_deque, p);
+    if (marking_deque->IsFull()) return;
   }
 }