Attempt to collect more garbage before panicking with out of memory.

src/heap.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 668 matching lines @@
   // Converts the given boolean condition to JavaScript boolean value.
   static Object* ToBoolean(bool condition) {
     return condition ? true_value() : false_value();
   }
 
   // Code that should be run before and after each GC.  Includes some
   // reporting/verification activities when compiled with DEBUG set.
   static void GarbageCollectionPrologue();
   static void GarbageCollectionEpilogue();
 
+  enum CollectionPolicy { NORMAL, AGGRESSIVE };
+
   // Performs garbage collection operation.
   // Returns whether required_space bytes are available after the collection.
-  static bool CollectGarbage(int required_space, AllocationSpace space);
+  static bool CollectGarbage(int required_space,
+                             AllocationSpace space,
+                             CollectionPolicy collectionPolicy = NORMAL);
 
   // Performs a full garbage collection. Force compaction if the
   // parameter is true.
-  static void CollectAllGarbage(bool force_compaction);
+  static void CollectAllGarbage(bool force_compaction,
+                                CollectionPolicy collectionPolicy = NORMAL);
+
+  // Last hope GC, should try to squeeze as much as possible.
+  static void CollectAllAvailableGarbage();
 
   // Notify the heap that a context has been disposed.
   static int NotifyContextDisposed() { return ++contexts_disposed_; }
 
   // Utility to invoke the scavenger. This is needed in test code to
   // ensure correct callback for weak global handles.
   static void PerformScavenge();
 
 #ifdef DEBUG
   // Utility used with flag gc-greedy.
@@ skipping 500 matching lines @@
   static void MarkMapPointersAsEncoded(bool encoded) {
     gc_safe_size_of_old_object_ = encoded
         ? &GcSafeSizeOfOldObjectWithEncodedMap
         : &GcSafeSizeOfOldObject;
   }
 
   // Checks whether a global GC is necessary
   static GarbageCollector SelectGarbageCollector(AllocationSpace space);
 
   // Performs garbage collection
-  static void PerformGarbageCollection(AllocationSpace space,
-                                       GarbageCollector collector,
-                                       GCTracer* tracer);
+  static void PerformGarbageCollection(GarbageCollector collector,
+                                       GCTracer* tracer,
+                                       CollectionPolicy collectionPolicy);
+
+  static const int kMinimumPromotionLimit = 2 * MB;
+  static const int kMinimumAllocationLimit = 8 * MB;
+
+  inline static void UpdateOldSpaceLimits();
 
   // Allocate an uninitialized object in map space.  The behavior is identical
   // to Heap::AllocateRaw(size_in_bytes, MAP_SPACE), except that (a) it doesn't
   // have to test the allocation space argument and (b) can reduce code size
   // (since both AllocateRaw and AllocateRawMap are inlined).
   MUST_USE_RESULT static inline Object* AllocateRawMap();
 
   // Allocate an uninitialized object in the global property cell space.
   MUST_USE_RESULT static inline Object* AllocateRawCell();
 
@@ skipping 791 matching lines @@
 
   // To speed up scavenge collections new space string are kept
   // separate from old space strings.
   static List<Object*> new_space_strings_;
   static List<Object*> old_space_strings_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_H_