Clean up some uses of Failures and MaybeObjects.

src/spaces.h

 // 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:
 //
 //     * 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 1704 matching lines @@
 
   // Cleans up the space, frees all pages in this space except those belonging
   // to the initial chunk, uncommits addresses in the initial chunk.
   void TearDown();
 
   // Checks whether an object/address is in this space.
   inline bool Contains(Address a);
   bool Contains(HeapObject* o) { return Contains(o->address()); }
 
   // Given an address occupied by a live object, return that object if it is
-  // in this space, or Failure::Exception() if it is not. The implementation
-  // iterates over objects in the page containing the address, the cost is
-  // linear in the number of objects in the page. It may be slow.
-  MUST_USE_RESULT MaybeObject* FindObject(Address addr);
+  // in this space, or a Smi if it is not.  The implementation iterates over
+  // objects in the page containing the address, the cost is linear in the
+  // number of objects in the page.  It may be slow.
+  Object* FindObject(Address addr);
 
   // During boot the free_space_map is created, and afterwards we may need
   // to write it into the free list nodes that were already created.
   void RepairFreeListsAfterBoot();
 
   // Prepares for a mark-compact GC.
   void PrepareForMarkCompact();
 
   // Current capacity without growing (Size() + Available()).
   intptr_t Capacity() { return accounting_stats_.Capacity(); }
@@ skipping 1095 matching lines @@
     return Size();
   }
 
   // Approximate amount of physical memory committed for this space.
   size_t CommittedPhysicalMemory();
 
   int PageCount() {
     return page_count_;
   }
 
-  // Finds an object for a given address, returns Failure::Exception()
-  // if it is not found. The function iterates through all objects in this
-  // space, may be slow.
-  MaybeObject* FindObject(Address a);
+  // Finds an object for a given address, returns a Smi if it is not found.
+  // The function iterates through all objects in this space, may be slow.
+  Object* FindObject(Address a);
 
   // Finds a large object page containing the given address, returns NULL
   // if such a page doesn't exist.
   LargePage* FindPage(Address a);
 
   // Frees unmarked objects.
   void FreeUnmarkedObjects();
 
   // Checks whether a heap object is in this space; O(1).
   bool Contains(HeapObject* obj);
 
   // Checks whether the space is empty.
   bool IsEmpty() { return first_page_ == NULL; }
 
   LargePage* first_page() { return first_page_; }
 
 #ifdef VERIFY_HEAP
   virtual void Verify();
 #endif
 
 #ifdef DEBUG
   virtual void Print();
   void ReportStatistics();
   void CollectCodeStatistics();
 #endif
   // Checks whether an address is in the object area in this space.  It
   // iterates all objects in the space. May be slow.
-  bool SlowContains(Address addr) { return !FindObject(addr)->IsFailure(); }
+  bool SlowContains(Address addr) { return FindObject(addr)->IsHeapObject(); }
 
  private:
   intptr_t max_capacity_;
   intptr_t maximum_committed_;
   // The head of the linked list of large object chunks.
   LargePage* first_page_;
   intptr_t size_;  // allocated bytes
   int page_count_;  // number of chunks
   intptr_t objects_size_;  // size of objects
   // Map MemoryChunk::kAlignment-aligned chunks to large pages covering them
@@ skipping 95 matching lines @@
   }
   // Must be small, since an iteration is used for lookup.
   static const int kMaxComments = 64;
 };
 #endif
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_SPACES_H_