Initial design for background compilation

runtime/vm/compiler.h

Index: runtime/vm/compiler.h
diff --git a/runtime/vm/compiler.h b/runtime/vm/compiler.h
index 9dc11b810541b2fa2ad60138e3752967a475021e..f31e00ac76d68087f82358f0ea1aa555a548e0a1 100644
--- a/runtime/vm/compiler.h
+++ b/runtime/vm/compiler.h
@@ -8,6 +8,7 @@
 #include "vm/allocation.h"
 #include "vm/growable_array.h"
 #include "vm/runtime_entry.h"
+#include "vm/thread_pool.h"
 
 namespace dart {
 
@@ -99,6 +100,35 @@ class Compiler : public AllStatic {
   static bool allow_recompilation_;
 };
 
+
+// Class to run optimizing compilation in a background thread.
+// Current implementation: one task per isolate, it dies with the owning
+// isolate.
+class BackgroundCompiler : public ThreadPool::Task {
+ public:
+  static void EnsureInit(Isolate* isolate);
+
+  static void Stop(BackgroundCompiler* task);
+
+  void CompileOptimized(const Function& function);
+
+ private:
+  explicit BackgroundCompiler(Isolate* isolate);
+
+  virtual void Run();
+
+  void Add(const Function& f) const;
+  RawFunction* RemoveOrNull() const;
+
+  Isolate* isolate_;
+  bool running_;
+  bool* done_;
+  Monitor* monitor_;
+  Monitor* done_monitor_;
+
+  DISALLOW_IMPLICIT_CONSTRUCTORS(BackgroundCompiler);
+};
+
 }  // namespace dart
 
 #endif  // VM_COMPILER_H_