Tenure allocation sites only when semi-space is maximum size.

src/heap.h

Index: src/heap.h
diff --git a/src/heap.h b/src/heap.h
index 8956e3c56b50f31af04c57a3caf9669d4c58f3f2..18a28f731a4f5a9d6dcfa4d6c5062309251e7144 100644
--- a/src/heap.h
+++ b/src/heap.h
@@ -1359,6 +1359,10 @@ class Heap {
 
   void DeoptMarkedAllocationSites();
 
+  bool changed_to_max_semi_space_size() {
+    return changed_to_max_semi_space_size_;
+  }
+
   // ObjectStats are kept in two arrays, counts and sizes. Related stats are
   // stored in a contiguous linear buffer. Stats groups are stored one after
   // another.
@@ -2005,7 +2009,6 @@ class Heap {
   // Adds an allocation site to the scratchpad if there is space left.
   void AddAllocationSiteToScratchpad(AllocationSite* site,
                                      ScratchpadSlotMode mode);
-
   void UpdateSurvivalStatistics(int start_new_space_size);
 
   static const int kYoungSurvivalRateHighThreshold = 90;
@@ -2019,6 +2022,12 @@ class Heap {
   intptr_t semi_space_copied_object_size_;
   double semi_space_copied_rate_;
 
+  // This is the pretenuring trigger for allocation sites that are in maybe
+  // tenure state. When we switched to the maximum new space size we deoptimize
+  // the code that belongs to the allocation site and derive the lifetime
+  // of the allocation site.
+  bool changed_to_max_semi_space_size_;
+
   // TODO(hpayer): Allocation site pretenuring may make this method obsolete.
   // Re-visit incremental marking heuristics.
   bool IsHighSurvivalRate() {