67 class ContiguousSpace;
  68 class CompactPoint;
  69 class OopsInGenClosure;
  70 class OopClosure;
  71 class ScanClosure;
  72 class FastScanClosure;
  73 class GenCollectedHeap;
  74 class GenRemSet;
  75 class GCStats;
  76 
  77 // A "ScratchBlock" represents a block of memory in one generation usable by
  78 // another.  It represents "num_words" free words, starting at and including
  79 // the address of "this".
  80 struct ScratchBlock {
  81   ScratchBlock* next;
  82   size_t num_words;
  83   HeapWord scratch_space[1];  // Actually, of size "num_words-2" (assuming
  84                               // first two fields are word-sized.)
  85 };
  86 
  87 
  88 class Generation: public CHeapObj<mtGC> {
  89   friend class VMStructs;
  90  private:
  91   jlong _time_of_last_gc; // time when last gc on this generation happened (ms)
  92   MemRegion _prev_used_region; // for collectors that want to "remember" a value for
  93                                // used region at some specific point during collection.
  94 
  95  protected:
  96   // Minimum and maximum addresses for memory reserved (not necessarily
  97   // committed) for generation.
  98   // Used by card marking code. Must not overlap with address ranges of
  99   // other generations.
 100   MemRegion _reserved;
 101 
 102   // Memory area reserved for generation
 103   VirtualSpace _virtual_space;
 104 
 105   // ("Weak") Reference processing support
 106   ReferenceProcessor* _ref_processor;
 107 

  67 class ContiguousSpace;
  68 class CompactPoint;
  69 class OopsInGenClosure;
  70 class OopClosure;
  71 class ScanClosure;
  72 class FastScanClosure;
  73 class GenCollectedHeap;
  74 class GenRemSet;
  75 class GCStats;
  76 
  77 // A "ScratchBlock" represents a block of memory in one generation usable by
  78 // another.  It represents "num_words" free words, starting at and including
  79 // the address of "this".
  80 struct ScratchBlock {
  81   ScratchBlock* next;
  82   size_t num_words;
  83   HeapWord scratch_space[1];  // Actually, of size "num_words-2" (assuming
  84                               // first two fields are word-sized.)
  85 };
  86 

  87 class Generation: public CHeapObj<mtGC> {
  88   friend class VMStructs;
  89  private:
  90   jlong _time_of_last_gc; // time when last gc on this generation happened (ms)
  91   MemRegion _prev_used_region; // for collectors that want to "remember" a value for
  92                                // used region at some specific point during collection.
  93 
  94  protected:
  95   // Minimum and maximum addresses for memory reserved (not necessarily
  96   // committed) for generation.
  97   // Used by card marking code. Must not overlap with address ranges of
  98   // other generations.
  99   MemRegion _reserved;
 100 
 101   // Memory area reserved for generation
 102   VirtualSpace _virtual_space;
 103 
 104   // ("Weak") Reference processing support
 105   ReferenceProcessor* _ref_processor;
 106