This adds a mechanism to invalidate code that was generated in the background. The invalidation can…

runtime/vm/object.cc

Index: runtime/vm/object.cc
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index 34208c73d96d222a668b6cc7a7860ec5fa7d88a0..d29117a3cf16e071bade2f032632910216063d57 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -2890,6 +2890,10 @@ class CHACodeArray : public WeakCodeReferences {
     }
   }
 
+  virtual void IncrementInvalidationGen() {
+    Isolate::Current()->IncrCHAInvalidationGen();
+  }
+
  private:
   const Class& cls_;
   DISALLOW_COPY_AND_ASSIGN(CHACodeArray);
@@ -7774,6 +7778,10 @@ class FieldDependentArray : public WeakCodeReferences {
     }
   }
 
+  virtual void IncrementInvalidationGen() {
+    Isolate::Current()->IncrFieldInvalidationGen();
+  }
+
  private:
   const Field& field_;
   DISALLOW_COPY_AND_ASSIGN(FieldDependentArray);
@@ -10814,6 +10822,10 @@ class PrefixDependentArray : public WeakCodeReferences {
     }
   }
 
+  virtual void IncrementInvalidationGen() {
+    Isolate::Current()->IncrPrefixInvalidationGen();
+  }
+
  private:
   const LibraryPrefix& prefix_;
   DISALLOW_COPY_AND_ASSIGN(PrefixDependentArray);