Optimize functions on a second thread.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 122550f5d5c42e8bbf55f0ea20202f2f2bdca999..3a78fd5e3e55fa7330b05a97daf282d6b3a19700 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -7249,6 +7249,18 @@ void JSFunction::MarkForLazyRecompilation() {
   ReplaceCode(builtins->builtin(Builtins::kLazyRecompile));
 }
 
+void JSFunction::MarkForParallelRecompilation() {
+  ASSERT(is_compiled() && !IsOptimized());
+  ASSERT(shared()->allows_lazy_compilation() || code()->optimizable());
+  Builtins* builtins = GetIsolate()->builtins();
+  ReplaceCode(builtins->builtin(Builtins::kParallelRecompile));
+
+  // Unlike MarkForLazyRecompilation, after queuing a function for
+  // recompilation on the compiler thread, we actually tail-call into
+  // the full code.  We reset the profiler ticks here so that the
+  // function doesn't bother the runtime profiler too much.
+  shared()->code()->set_profiler_ticks(0);
+}
 
 static bool CompileLazyHelper(CompilationInfo* info,
                               ClearExceptionFlag flag) {