[heap] Don't use black pages for map, code and, lo space. Instead color objects black.

src/heap/spaces.cc

Index: src/heap/spaces.cc
diff --git a/src/heap/spaces.cc b/src/heap/spaces.cc
index 0f50cdd0d35028a47fdb59d75a3a4c603267eeda..df64e2beb76a065a17bac9a13e9799de6c019977 100644
--- a/src/heap/spaces.cc
+++ b/src/heap/spaces.cc
@@ -1183,7 +1183,8 @@ bool PagedSpace::Expand() {
 
   // When incremental marking was activated, old generation pages are allocated
   // black.
-  if (heap()->incremental_marking()->black_allocation()) {
+  if (heap()->incremental_marking()->black_allocation() &&
+      identity() != CODE_SPACE && identity() != MAP_SPACE) {

[ulan, 2016/04/06 16:44:43]

Let's whitelist instead of blacklist, identity() == OLD_SPACE

[Hannes Payer (out of office), 2016/04/06 21:24:39]

Done.

     Bitmap::SetAllBits(p);
     p->SetFlag(Page::BLACK_PAGE);
     if (FLAG_trace_incremental_marking) {
@@ -2901,11 +2902,6 @@ AllocationResult LargeObjectSpace::AllocateRaw(int object_size,
   }
 
   HeapObject* object = page->GetObject();
-  if (heap()->incremental_marking()->black_allocation()) {
-    MarkBit mark_bit = Marking::MarkBitFrom(object);
-    Marking::MarkBlack(mark_bit);
-    page->SetFlag(Page::BLACK_PAGE);
-  }
   MSAN_ALLOCATED_UNINITIALIZED_MEMORY(object->address(), object_size);
 
   if (Heap::ShouldZapGarbage()) {