Enable preemption in d8.

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 210 matching lines @@
 
   friend class StackLimitCheck;
   friend class PostponeInterruptsScope;
 };
 
 
 // Support for checking for stack-overflows in C++ code.
 class StackLimitCheck BASE_EMBEDDED {
  public:
   bool HasOverflowed() const {
-    return reinterpret_cast<uintptr_t>(this) < StackGuard::climit();
+    // Stack has overflowed in C++ code only if stack pointer exceeds the C++
+    // stack guard and the limits are not set to interrupt values.
+    // TODO(214): Stack overflows are ignored if a interrupt is pending. This
+    // code should probably always use the initial C++ limit.
+    return (reinterpret_cast<uintptr_t>(this) < StackGuard::climit()) &&
+           StackGuard::IsStackOverflow();
   }
 };
 
 
 // Support for temporarily postponing interrupts. When the outermost
 // postpone scope is left the interrupts will be re-enabled and any
 // interrupts that occurred while in the scope will be taken into
 // account.
 class PostponeInterruptsScope BASE_EMBEDDED {
  public:
@@ skipping 17 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_