Allocation site pretenuring.

src/heap.h

Index: src/heap.h
diff --git a/src/heap.h b/src/heap.h
index 1c8e0e16e60405f0c03b08b971057b51fa7a9d45..fa3b3bd334b18d7551c9972e3ff7fbda42bc2a11 100644
--- a/src/heap.h
+++ b/src/heap.h
@@ -2186,6 +2186,14 @@ class Heap {
   void ProcessArrayBuffers(WeakObjectRetainer* retainer, bool record_slots);
   void ProcessAllocationSites(WeakObjectRetainer* retainer, bool record_slots);
 
+  // Deopts all dependent code of the currently registered allocation sites and
+  // sets the given pretenuring decisions to undecided.
+  void ClearAllAllocationSitesDependentCode();
+
+  // Evaluates local pretenuring and calls ClearAllAllocationSitesDependentCode
+  // if too many objects died in the old generation.
+  void EvaluateLocalPretenuring(uint64_t size_of_objects_before_gc);
+
   // Called on heap tear-down.
   void TearDownArrayBuffers();
 
@@ -2229,6 +2237,8 @@ class Heap {
   static const int kYoungSurvivalRateLowThreshold = 10;
   static const int kYoungSurvivalRateAllowedDeviation = 15;
 
+  static const int kOldSurvivalRateLowThreshold = 20;
+
   int young_survivors_after_last_gc_;
   int high_survival_rate_period_length_;
   int low_survival_rate_period_length_;