Get rid of distinction between below- and above-watermark in page allocation....

src/heap.h

Index: src/heap.h
===================================================================
--- src/heap.h	(revision 7102)
+++ src/heap.h	(working copy)
@@ -1,4 +1,4 @@
-// Copyright 2010 the V8 project authors. All rights reserved.
+// Copyright 2011 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:
@@ -763,10 +763,19 @@
   // collect more garbage.
   inline static bool CollectGarbage(AllocationSpace space);
 
+  static const int kNoGCFlags = 0;
+  static const int kForceCompactionMask = 1;
+  static const int kSweepPreciselyMask = 2;

[Vyacheslav Egorov (Chromium), 2011/03/15 09:20:09]

maybe better hide the concept of conservative and precise sweep and just call it
kEnsureIterableMask or something like that?

[Erik Corry, 2011/03/17 13:39:17]

Done.

+
   // Performs a full garbage collection. Force compaction if the
   // parameter is true.
-  static void CollectAllGarbage(bool force_compaction);
+  static void CollectAllGarbage(int flags);
 
+
+  // Ensure that we have swept all spaces in such a way that we can iterate
+  // over live objects.  May cause a GC.
+  static void EnsureHeapIsIterable();
+
   // Last hope GC, should try to squeeze as much as possible.
   static void CollectAllAvailableGarbage();
 
@@ -1610,7 +1619,8 @@
 
 // A HeapIterator provides iteration over the whole heap. It
 // aggregates the specific iterators for the different spaces as
-// these can only iterate over one space only.
+// these can only iterate over one space only.  It can only be guaranteed
+// to iterate over live objects.
 //
 // HeapIterator can skip free list nodes (that is, de-allocated heap
 // objects that still remain in the heap). As implementation of free
@@ -1621,28 +1631,18 @@
 
 class HeapIterator BASE_EMBEDDED {
  public:
-  enum HeapObjectsFiltering {
-    kNoFiltering,
-    kFilterFreeListNodes,
-    kFilterUnreachable
-  };
-
   HeapIterator();
-  explicit HeapIterator(HeapObjectsFiltering filtering);
   ~HeapIterator();
 
-  HeapObject* next();
-  void reset();
+  HeapObject* Next();
+  void Reset();
 
  private:
   // Perform the initialization.
   void Init();
   // Perform all necessary shutdown (destruction) work.
   void Shutdown();
-  HeapObject* NextObject();
 
-  HeapObjectsFiltering filtering_;
-  HeapObjectsFilter* filter_;
   // Space iterator for iterating all the spaces.
   SpaceIterator* space_iterator_;
   // Object iterator for the space currently being iterated.