Allow direct allocation in old pointer space.

src/assembler.cc

Index: src/assembler.cc
diff --git a/src/assembler.cc b/src/assembler.cc
index 8d8208d0990fdd0645b8aeae9a00dd809506f89f..d206c5bc7d4910e45d5f2f34b6eda5fc2640e6e0 100644
--- a/src/assembler.cc
+++ b/src/assembler.cc
@@ -1188,6 +1188,20 @@ ExternalReference ExternalReference::new_space_allocation_limit_address(
 }
 
 
+ExternalReference ExternalReference::old_pointer_space_allocation_top_address(
+    Isolate* isolate) {
+  return ExternalReference(
+      isolate->heap()->OldPointerSpaceAllocationTopAddress());
+}
+
+
+ExternalReference ExternalReference::old_pointer_space_allocation_limit_address(
+    Isolate* isolate) {
+  return ExternalReference(
+      isolate->heap()->OldPointerSpaceAllocationLimitAddress());
+}
+
+
 ExternalReference ExternalReference::handle_scope_level_address(
     Isolate* isolate) {
   return ExternalReference(HandleScope::current_level_address(isolate));