Add support for forceful termination of JavaScript execution.

src/v8threads.cc

Index: src/v8threads.cc
===================================================================
--- src/v8threads.cc	(revision 2717)
+++ src/v8threads.cc	(working copy)
@@ -151,6 +151,10 @@
   from = RegExpStack::RestoreStack(from);
   from = Bootstrapper::RestoreState(from);
   Thread::SetThreadLocal(thread_state_key, NULL);
+  if (state->terminate_on_restore()) {
+    StackGuard::TerminateExecution();
+    state->set_terminate_on_restore(false);
+  }
   state->set_id(kInvalidId);
   state->Unlink();
   state->LinkInto(ThreadState::FREE_LIST);
@@ -188,6 +192,7 @@
 
 
 ThreadState::ThreadState() : id_(ThreadManager::kInvalidId),
+                             terminate_on_restore_(false),
                              next_(this), previous_(this) {
 }
 
@@ -317,11 +322,25 @@
 
 void ThreadManager::AssignId() {
   if (!Thread::HasThreadLocal(thread_id_key)) {
-    Thread::SetThreadLocalInt(thread_id_key, next_id_++);
+    ASSERT(Locker::IsLocked());
+    int thread_id = next_id_++;
+    Thread::SetThreadLocalInt(thread_id_key, thread_id);
+    Top::set_thread_id(thread_id);
   }
 }
 
 
+void ThreadManager::TerminateExecution(int thread_id) {
+  for (ThreadState* state = ThreadState::FirstInUse();
+       state != NULL;
+       state = state->Next()) {
+    if (thread_id == state->id()) {
+      state->set_terminate_on_restore(true);
+    }
+  }
+}
+
+
 // This is the ContextSwitcher singleton. There is at most a single thread
 // running which delivers preemption events to V8 threads.
 ContextSwitcher* ContextSwitcher::singleton_ = NULL;