Introduce per-isolate assert scopes and API to guard JS execution.

src/heap.h

 // Copyright 2012 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 1473 matching lines @@
   enum HeapState { NOT_IN_GC, SCAVENGE, MARK_COMPACT };
   inline HeapState gc_state() { return gc_state_; }
 
   inline bool IsInGCPostProcessing() { return gc_post_processing_depth_ > 0; }
 
 #ifdef DEBUG
   void set_allocation_timeout(int timeout) {
     allocation_timeout_ = timeout;
   }
 
-  bool disallow_allocation_failure() {
-    return disallow_allocation_failure_;
-  }
-
   void TracePathToObjectFrom(Object* target, Object* root);
   void TracePathToObject(Object* target);
   void TracePathToGlobal();
 #endif
 
   // Callback function passed to Heap::Iterate etc.  Copies an object if
   // necessary, the object might be promoted to an old space.  The caller must
   // ensure the precondition that the object is (a) a heap object and (b) in
   // the heap's from space.
   static inline void ScavengePointer(HeapObject** p);
@@ skipping 489 matching lines @@
     roots_[k##camel_name##RootIndex] = value;                                  \
   }
   ROOT_LIST(ROOT_ACCESSOR)
 #undef ROOT_ACCESSOR
 
 #ifdef DEBUG
   // If the --gc-interval flag is set to a positive value, this
   // variable holds the value indicating the number of allocations
   // remain until the next failure and garbage collection.
   int allocation_timeout_;
-
-  // Do we expect to be able to handle allocation failure at this
-  // time?
-  bool disallow_allocation_failure_;
 #endif  // DEBUG
 
   // Indicates that the new space should be kept small due to high promotion
   // rates caused by the mutator allocating a lot of long-lived objects.
   // TODO(hpayer): change to bool if no longer accessed from generated code
   intptr_t new_space_high_promotion_mode_active_;
 
   // Limit that triggers a global GC on the next (normally caused) GC.  This
   // is checked when we have already decided to do a GC to help determine
   // which collector to invoke, before expanding a paged space in the old
@@ skipping 488 matching lines @@
   // configured through the API until it is set up.
   bool configured_;
 
   ExternalStringTable external_string_table_;
 
   VisitorDispatchTable<ScavengingCallback> scavenging_visitors_table_;
 
   MemoryChunk* chunks_queued_for_free_;
 
   Mutex* relocation_mutex_;
-#ifdef DEBUG
-  bool relocation_mutex_locked_by_optimizer_thread_;
-#endif  // DEBUG;
 
   friend class Factory;
   friend class GCTracer;
-  friend class DisallowAllocationFailure;
   friend class AlwaysAllocateScope;
   friend class Page;
   friend class Isolate;
   friend class MarkCompactCollector;
   friend class MarkCompactMarkingVisitor;
   friend class MapCompact;
 #ifdef VERIFY_HEAP
   friend class NoWeakObjectVerificationScope;
 #endif
 
@@ skipping 29 matching lines @@
   intptr_t* memory_allocator_capacity;       // 20
   int* objects_per_type;                // 21
   int* size_per_type;                   // 22
   int* os_error;                        // 23
   int* end_marker;                      // 24
   intptr_t* property_cell_space_size;   // 25
   intptr_t* property_cell_space_capacity;    // 26
 };
 
 
-class DisallowAllocationFailure {
- public:
-  inline DisallowAllocationFailure();
-  inline ~DisallowAllocationFailure();
-
-#ifdef DEBUG
- private:
-  bool old_state_;
-#endif
-};
-
-
 class AlwaysAllocateScope {
  public:
-  inline AlwaysAllocateScope();
+  explicit inline AlwaysAllocateScope(Isolate* isolate);
   inline ~AlwaysAllocateScope();
 
  private:
   // Implicitly disable artificial allocation failures.
-  DisallowAllocationFailure disallow_allocation_failure_;
+  Heap* heap_;
+  DisallowAllocationFailure daf_;
 };
 
 
 #ifdef VERIFY_HEAP
 class NoWeakObjectVerificationScope {
  public:
   inline NoWeakObjectVerificationScope();
   inline ~NoWeakObjectVerificationScope();
 };
 #endif
@@ skipping 519 matching lines @@
   DisallowHeapAllocation no_allocation;  // i.e. no gc allowed.
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_H_