[Isolates]...

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 122 matching lines @@
   // object. Used for support calling objects as functions.
   static Handle<Object> GetFunctionDelegate(Handle<Object> object);
 
   // Get a function delegate (or undefined) for the given non-function
   // object. Used for support calling objects as constructors.
   static Handle<Object> GetConstructorDelegate(Handle<Object> object);
 };
 
 
 class ExecutionAccess;
+class Isolate;
 
 
 // StackGuard contains the handling of the limits that are used to limit the
 // number of nested invocations of JavaScript and the stack size used in each
 // invocation.
-class StackGuard : public AllStatic {
+class StackGuard {
  public:
   // Pass the address beyond which the stack should not grow.  The stack
   // is assumed to grow downwards.
-  static void SetStackLimit(uintptr_t limit);
+  void SetStackLimit(uintptr_t limit);
 
   // Threading support.
-  static char* ArchiveStackGuard(char* to);
-  static char* RestoreStackGuard(char* from);
-  static int ArchiveSpacePerThread();
-  static void FreeThreadResources();
+  char* ArchiveStackGuard(char* to);
+  char* RestoreStackGuard(char* from);
+  static int ArchiveSpacePerThread() { return sizeof(ThreadLocal); }
+  void FreeThreadResources();
   // Sets up the default stack guard for this thread if it has not
   // already been set up.
-  static void InitThread(const ExecutionAccess& lock);
+  void InitThread(const ExecutionAccess& lock);
   // Clears the stack guard for this thread so it does not look as if
   // it has been set up.
-  static void ClearThread(const ExecutionAccess& lock);
+  void ClearThread(const ExecutionAccess& lock);
 
-  static bool IsStackOverflow();
-  static bool IsPreempted();
-  static void Preempt();
-  static bool IsInterrupted();
-  static void Interrupt();
-  static bool IsTerminateExecution();
-  static void TerminateExecution();
+  bool IsStackOverflow();
+  bool IsPreempted();
+  void Preempt();
+  bool IsInterrupted();
+  void Interrupt();
+  bool IsTerminateExecution();
+  void TerminateExecution();
 #ifdef ENABLE_DEBUGGER_SUPPORT
-  static bool IsDebugBreak();
-  static void DebugBreak();
-  static bool IsDebugCommand();
-  static void DebugCommand();
+  bool IsDebugBreak();
+  void DebugBreak();
+  bool IsDebugCommand();
+  void DebugCommand();
 #endif
-  static void Continue(InterruptFlag after_what);
+  void Continue(InterruptFlag after_what);
 
   // This provides an asynchronous read of the stack limits 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() {
+  uintptr_t climit() {
     return thread_local_.climit_;
   }
-  static uintptr_t jslimit() {
+  uintptr_t jslimit() {
     return thread_local_.jslimit_;
   }
-  static uintptr_t real_jslimit() {
+  uintptr_t real_jslimit() {
     return thread_local_.real_jslimit_;
   }
-  static Address address_of_jslimit() {
+  Address address_of_jslimit() {
     return reinterpret_cast<Address>(&thread_local_.jslimit_);
   }
-  static Address address_of_real_jslimit() {
+  Address address_of_real_jslimit() {
     return reinterpret_cast<Address>(&thread_local_.real_jslimit_);
   }
 
  private:
+  StackGuard();
+
+  Isolate* isolate_; // TODO(isolates): Technically this could be calculated

[Vitaly Repeshko, 2010/06/09 21:22:38]

The comment was formatted correctly. I meant that the field itself (and its
comment) should be moved to be next to other fields of this class (to line 270).

+                     //                 directly from a pointer to StackGuard.
+
   // You should hold the ExecutionAccess lock when calling this method.
-  static bool has_pending_interrupts(const ExecutionAccess& lock) {
+  bool has_pending_interrupts(const ExecutionAccess& lock) {
     // Sanity check: We shouldn't be asking about pending interrupts
     // unless we're not postponing them anymore.
     ASSERT(!should_postpone_interrupts(lock));
     return thread_local_.interrupt_flags_ != 0;
   }
 
   // You should hold the ExecutionAccess lock when calling this method.
-  static bool should_postpone_interrupts(const ExecutionAccess& lock) {
+  bool should_postpone_interrupts(const ExecutionAccess& lock) {
     return thread_local_.postpone_interrupts_nesting_ > 0;
   }
 
   // You should hold the ExecutionAccess lock when calling this method.
-  static void set_interrupt_limits(const ExecutionAccess& lock) {
-    // Ignore attempts to interrupt when interrupts are postponed.
-    if (should_postpone_interrupts(lock)) return;
-    thread_local_.jslimit_ = kInterruptLimit;
-    thread_local_.climit_ = kInterruptLimit;
-    Heap::SetStackLimits();
-  }
+  inline void set_interrupt_limits(const ExecutionAccess& lock);
 
   // Reset limits to actual values. For example after handling interrupt.
   // You should hold the ExecutionAccess lock when calling this method.
-  static void reset_limits(const ExecutionAccess& lock) {
-    thread_local_.jslimit_ = thread_local_.real_jslimit_;
-    thread_local_.climit_ = thread_local_.real_climit_;
-    Heap::SetStackLimits();
-  }
+  inline void reset_limits(const ExecutionAccess& lock);
 
   // Enable or disable interrupts.
-  static void EnableInterrupts();
-  static void DisableInterrupts();
+  void EnableInterrupts();
+  void DisableInterrupts();
 
   static const uintptr_t kLimitSize = kPointerSize * 128 * KB;
 
 #ifdef V8_TARGET_ARCH_X64
   static const uintptr_t kInterruptLimit = V8_UINT64_C(0xfffffffffffffffe);
   static const uintptr_t kIllegalLimit = V8_UINT64_C(0xfffffffffffffff8);
 #else
   static const uintptr_t kInterruptLimit = 0xfffffffe;
   static const uintptr_t kIllegalLimit = 0xfffffff8;
 #endif
 
   class ThreadLocal {
    public:
-    ThreadLocal() { Clear(); }
+    ThreadLocal();
     // You should hold the ExecutionAccess lock when you call Initialize or
     // Clear.
-    void Initialize();
     void Clear();
+    
+    // Returns true if the heap's stack limits should be set, false if not.
+    bool Initialize();
 
     // The stack limit is split into a JavaScript and a C++ stack limit. These
     // two are the same except when running on a simulator where the C++ and
     // JavaScript stacks are separate. Each of the two stack limits have two
     // values. The one eith the real_ prefix is the actual stack limit
     // set for the VM. The one without the real_ prefix has the same value as
     // the actual stack limit except when there is an interruption (e.g. debug
     // break or preemption) in which case it is lowered to make stack checks
     // fail. Both the generated code and the runtime system check against the
     // one without the real_ prefix.
     uintptr_t real_jslimit_;  // Actual JavaScript stack limit set for the VM.
     uintptr_t jslimit_;
     uintptr_t real_climit_;  // Actual C++ stack limit set for the VM.
     uintptr_t climit_;
 
     int nesting_;
     int postpone_interrupts_nesting_;
     int interrupt_flags_;
   };
 
-  static ThreadLocal thread_local_;
+  ThreadLocal thread_local_;
+  Thread::LocalStorageKey stack_limit_key_;
 
+  friend class Isolate;
   friend class StackLimitCheck;
   friend class PostponeInterruptsScope;
-};
 
-
-// Support for checking for stack-overflows in C++ code.
-class StackLimitCheck BASE_EMBEDDED {
- public:
-  bool HasOverflowed() const {
-    // 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:
-  PostponeInterruptsScope() {
-    StackGuard::thread_local_.postpone_interrupts_nesting_++;
-    StackGuard::DisableInterrupts();
-  }
-
-  ~PostponeInterruptsScope() {
-    if (--StackGuard::thread_local_.postpone_interrupts_nesting_ == 0) {
-      StackGuard::EnableInterrupts();
-    }
-  }
+  DISALLOW_COPY_AND_ASSIGN(StackGuard);
 };
 
 
 class GCExtension : public v8::Extension {
  public:
   GCExtension() : v8::Extension("v8/gc", kSource) {}
   virtual v8::Handle<v8::FunctionTemplate> GetNativeFunction(
       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_