Add support for forceful termination of JavaScript execution.

src/execution.h

 // Copyright 2006-2008 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 19 matching lines @@
 
 namespace v8 {
 namespace internal {
 
 
 // Flag used to set the interrupt causes.
 enum InterruptFlag {
   INTERRUPT = 1 << 0,
   DEBUGBREAK = 1 << 1,
   DEBUGCOMMAND = 1 << 2,
-  PREEMPT = 1 << 3
+  PREEMPT = 1 << 3,
+  TERMINATE = 1 << 4
 };
 
 class Execution : public AllStatic {
  public:
   // Call a function, the caller supplies a receiver and an array
   // of arguments. Arguments are Object* type. After function returns,
   // pointers in 'args' might be invalid.
   //
   // *pending_exception tells whether the invoke resulted in
   // a pending exception.
@@ skipping 106 matching lines @@
   // Threading support.
   static char* ArchiveStackGuard(char* to);
   static char* RestoreStackGuard(char* from);
   static int ArchiveSpacePerThread();
 
   static bool IsStackOverflow();
   static bool IsPreempted();
   static void Preempt();
   static bool IsInterrupted();
   static void Interrupt();
+  static bool IsTerminateExecution();
+  static void TerminateExecution();
+#ifdef ENABLE_DEBUGGER_SUPPORT
+  static bool IsDebugBreak();
+  static void DebugBreak();
+  static bool IsDebugCommand();
+  static void DebugCommand();
+#endif
   static void Continue(InterruptFlag after_what);
-#ifdef ENABLE_DEBUGGER_SUPPORT
-  static void DebugBreak();
-  static void DebugCommand();
-  static bool IsDebugBreak();
-  static bool IsDebugCommand();
-#endif
 
  private:
   // You should hold the ExecutionAccess lock when calling this method.
   static bool IsSet(const ExecutionAccess& lock);
 
   // This provides an asynchronous read of the stack limit for the current
   // thread.  There are no locks protecting this, but it is assumed that you
   // have the global V8 lock if you are using multiple V8 threads.
   static uintptr_t climit() {
     return thread_local_.climit_;
@@ skipping 96 matching lines @@
       v8::Handle<v8::String> name);
   static v8::Handle<v8::Value> GC(const v8::Arguments& args);
  private:
   static const char* kSource;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_EXECUTION_H_