Support slots recording for compaction during incremental marking.

src/spaces.h

Index: src/spaces.h
diff --git a/src/spaces.h b/src/spaces.h
index 5b47c34b895b82dfaffa3c24a18101c3b92190fd..0f4bd3ee44fb65fb3d19fe5487f3a0076d8484d1 100644
--- a/src/spaces.h
+++ b/src/spaces.h
@@ -392,9 +392,24 @@ class MemoryChunk {
     NEW_SPACE_BELOW_AGE_MARK,
     CONTAINS_ONLY_DATA,
     EVACUATION_CANDIDATE,
+    EVACUATED,
     NUM_MEMORY_CHUNK_FLAGS
   };
 
+
+  static const int kPointersToHereAreInterestingMask =
+      1 << POINTERS_TO_HERE_ARE_INTERESTING;
+
+  static const int kPointersFromHereAreInterestingMask =
+      1 << POINTERS_FROM_HERE_ARE_INTERESTING;
+
+  static const int kEvacuationCandidateMask =
+      1 << EVACUATION_CANDIDATE;
+
+  static const int kEvacuationCandidateOrNewSpaceMask =
+      (1 << EVACUATION_CANDIDATE) | (1 << IN_FROM_SPACE) | (1 << IN_TO_SPACE);
+
+
   void SetFlag(int flag) {
     flags_ |= (1 << flag);
   }
@@ -609,16 +624,19 @@ class Page : public MemoryChunk {
   bool IsEvacuationCandidate() { return IsFlagSet(EVACUATION_CANDIDATE); }
 
   bool IsEvacuationCandidateOrNewSpace() {
-    intptr_t mask = (1 << EVACUATION_CANDIDATE) |
-        (1 << IN_FROM_SPACE) |
-        (1 << IN_TO_SPACE);
-    return (flags_ & mask) != 0;
+    return (flags_ & kEvacuationCandidateOrNewSpaceMask) != 0;
   }
 
   void MarkEvacuationCandidate() { SetFlag(EVACUATION_CANDIDATE); }
 
   void ClearEvacuationCandidate() { ClearFlag(EVACUATION_CANDIDATE); }
 
+  bool WasEvacuated() { return IsFlagSet(EVACUATED); }
+
+  void MarkEvacuated() { SetFlag(EVACUATED); }
+
+  void ClearEvacuated() { ClearFlag(EVACUATED); }
+
   friend class MemoryAllocator;
 };
 
@@ -1035,6 +1053,9 @@ class PageIterator BASE_EMBEDDED {
 // space.
 class AllocationInfo {
  public:
+  AllocationInfo() : top(NULL), limit(NULL) {
+  }
+
   Address top;  // Current allocation top.
   Address limit;  // Current allocation limit.
 
@@ -1228,6 +1249,10 @@ class FreeList BASE_EMBEDDED {
   static const int kMinBlockSize = 3 * kPointerSize;
   static const int kMaxBlockSize = Page::kMaxHeapObjectSize;
 
+  FreeListNode* PickNodeFromList(FreeListNode** list, int* node_size);
+
+  FreeListNode* FindNodeFor(int size_in_bytes, int* node_size);
+
   PagedSpace* owner_;
   Heap* heap_;
 
@@ -1423,7 +1448,6 @@ class PagedSpace : public Space {
   Page* FirstPage() { return anchor_.next_page(); }
   Page* LastPage() { return anchor_.prev_page(); }
 
-
   bool IsFragmented(Page* p) {
     intptr_t sizes[4];
     free_list_.CountFreeListItems(p, sizes);
@@ -1448,6 +1472,8 @@ class PagedSpace : public Space {
     return ratio > 15;
   }
 
+  void EvictEvacuationCandidatesFromFreeLists();
+
  protected:
   // Maximum capacity of this space.
   intptr_t max_capacity_;
@@ -2180,10 +2206,6 @@ class OldSpace : public PagedSpace {
     return page->ObjectAreaEnd();
   }
 
-  // Prepare for full garbage collection.  Resets the relocation pointer and
-  // clears the free list.
-  virtual void PrepareForMarkCompact();
-
  public:
   TRACK_MEMORY("OldSpace")
 };