Optimize functions on a second thread.

src/vm-state-inl.h

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 29 matching lines @@
 // VMState construction and popped by destruction.
 //
 inline const char* StateToString(StateTag state) {
   switch (state) {
     case JS:
       return "JS";
     case GC:
       return "GC";
     case COMPILER:
       return "COMPILER";
+    case PARALLEL_COMPILER_PROLOGUE:
+      return "PARALLEL_COMPILER_PROLOGUE";
     case OTHER:
       return "OTHER";
     case EXTERNAL:
       return "EXTERNAL";
     default:
       UNREACHABLE();
       return NULL;
   }
 }
 
@@ skipping 28 matching lines @@
 }
 
 ExternalCallbackScope::~ExternalCallbackScope() {
   isolate_->set_external_callback(previous_callback_);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_VM_STATE_INL_H_