152   // Returns true iff the given block is not allocated.

   152   // Returns true iff the given block is not allocated.

   153   virtual bool is_free_block(const HeapWord* p) const = 0;

   153   virtual bool is_free_block(const HeapWord* p) const = 0;

   154 

   154 

   155   // Test whether p is double-aligned

   155   // Test whether p is double-aligned

   156   static bool is_aligned(void* p) {

   156   static bool is_aligned(void* p) {

   158   }

   158   }

   159 

   159 

   160   // Size computations.  Sizes are in bytes.

   160   // Size computations.  Sizes are in bytes.

   161   size_t capacity()     const { return byte_size(bottom(), end()); }

   161   size_t capacity()     const { return byte_size(bottom(), end()); }

   162   virtual size_t used() const = 0;

   162   virtual size_t used() const = 0;