ghc/rts/Storage.h

   1 /* -----------------------------------------------------------------------------
   2  * $Id: Storage.h,v 1.5 1999/01/21 10:31:52 simonm Exp $
   3  *
   4  * External Storage Manger Interface
   5  *
   6  * ---------------------------------------------------------------------------*/
   7
   8 #ifndef STORAGE_H
   9 #define STORAGE_H
  10
  11 #include "Block.h"
  12 #include "BlockAlloc.h"
  13 #include "StoragePriv.h"
  14
  15 /* -----------------------------------------------------------------------------
  16    Initialisation / De-initialisation
  17    -------------------------------------------------------------------------- */
  18
  19 extern void initStorage(void);
  20 extern void exitStorage(void);
  21
  22 /* -----------------------------------------------------------------------------
  23    Generic allocation
  24
  25    StgPtr allocate(int n)       Allocates a chunk of contiguous store
  26                                 n words long, returning a pointer to
  27                                 the first word.  Always succeeds.
  28
  29                                 Don't forget to TICK_ALLOC_XXX(...)
  30                                 after calling allocate, for the
  31                                 benefit of the ticky-ticky profiler.
  32
  33    rtsBool doYouWantToGC(void)  Returns True if the storage manager is
  34                                 ready to perform a GC, False otherwise.
  35
  36    lnat  allocated_bytes(void)  Returns the number of bytes allocated
  37                                 via allocate() since the last GC.
  38                                 Used in the reoprting of statistics.
  39    -------------------------------------------------------------------------- */
  40
  41 extern StgPtr  allocate(nat n);
  42 static inline rtsBool doYouWantToGC(void)
  43 {
  44   return (alloc_blocks >= alloc_blocks_lim);
  45 }
  46 extern lnat allocated_bytes(void);
  47
  48 /* -----------------------------------------------------------------------------
  49    ExtendNursery(hp,hplim)      When hplim is reached, try to grab
  50                                 some more allocation space.  Returns
  51                                 False if the allocation space is
  52                                 exhausted, and the application should
  53                                 call GarbageCollect().
  54   -------------------------------------------------------------------------- */
  55
  56 #define ExtendNursery(hp,hplim)                 \
  57   (current_nursery->free = (P_)(hp)+1,          \
  58    current_nursery->link == NULL ? rtsFalse :   \
  59    (current_nursery = current_nursery->link,    \
  60     OpenNursery(hp,hplim),                      \
  61     rtsTrue))
  62
  63 extern void PleaseStopAllocating(void);
  64
  65 /* -----------------------------------------------------------------------------
  66    Performing Garbage Collection
  67
  68    GarbageCollect(get_roots)    Performs a garbage collection.
  69                                 'get_roots' is called to find all the
  70                                 roots that the system knows about.
  71
  72    StgClosure                   Called by get_roots on each root.
  73    MarkRoot(StgClosure *p)      Returns the new location of the root.
  74    -------------------------------------------------------------------------- */
  75
  76 extern void   GarbageCollect(void (*get_roots)(void));
  77 extern StgClosure *MarkRoot(StgClosure *p);
  78
  79 /* -----------------------------------------------------------------------------
  80    Generational garbage collection support
  81
  82    RecordMutable(StgPtr p)       Informs the garbage collector that a
  83                                  previously immutable object has
  84                                  become (permanently) mutable.  Used
  85                                  by thawArray and similar.
  86
  87    UpdateWithIndirection(p1,p2)  Updates the object at p1 with an
  88                                  indirection pointing to p2.  This is
  89                                  normally called for objects in an old
  90                                  generation (>0) when they are updated.
  91
  92    -------------------------------------------------------------------------- */
  93
  94 extern void recordMutable(StgMutClosure *p);
  95
  96 static inline void
  97 updateWithIndirection(StgClosure *p1, StgClosure *p2)
  98 {
  99   bdescr *bd;
 100
 101   bd = Bdescr((P_)p1);
 102   if (bd->gen->no == 0) {
 103     SET_INFO(p1,&IND_info);
 104     ((StgInd *)p1)->indirectee = p2;
 105     TICK_UPD_NEW_IND();
 106   } else {
 107     SET_INFO(p1,&IND_OLDGEN_info);
 108     ((StgIndOldGen *)p1)->indirectee = p2;
 109     ((StgIndOldGen *)p1)->mut_link = bd->gen->mut_list;
 110     bd->gen->mut_list = (StgMutClosure *)p1;
 111     TICK_UPD_OLD_IND();
 112   }
 113 }
 114
 115 /* -----------------------------------------------------------------------------
 116    The CAF list - used to let us revert CAFs
 117
 118    -------------------------------------------------------------------------- */
 119
 120 extern StgCAF* enteredCAFs;
 121
 122 #endif STORAGE_H
 123