ghc/rts/Storage.h

   1 /* -----------------------------------------------------------------------------
   2  * $Id: Storage.h,v 1.2 1998/12/02 13:28:58 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    rtsBool doYouWantToGC(void)  Returns True if the storage manager is
  30                                 ready to perform a GC, False otherwise.
  31
  32    lnat  allocated_bytes(void)  Returns the number of bytes allocated
  33                                 via allocate() since the last GC.
  34                                 Used in the reoprting of statistics.
  35    -------------------------------------------------------------------------- */
  36
  37 extern StgPtr  allocate(nat n);
  38 static inline rtsBool doYouWantToGC(void)
  39 {
  40   return (alloc_blocks >= alloc_blocks_lim);
  41 }
  42 extern lnat allocated_bytes(void);
  43
  44 /* -----------------------------------------------------------------------------
  45    ExtendNursery(hp,hplim)      When hplim is reached, try to grab
  46                                 some more allocation space.  Returns
  47                                 False if the allocation space is
  48                                 exhausted, and the application should
  49                                 call GarbageCollect().
  50   -------------------------------------------------------------------------- */
  51
  52 #define ExtendNursery(hp,hplim)                 \
  53   (current_nursery->free = (P_)(hp)+1,          \
  54    current_nursery->link == NULL ? rtsFalse :   \
  55    (current_nursery = current_nursery->link,    \
  56     OpenNursery(hp,hplim),                      \
  57     rtsTrue))
  58
  59 extern void PleaseStopAllocating(void);
  60
  61 /* -----------------------------------------------------------------------------
  62    Performing Garbage Collection
  63
  64    GarbageCollect(get_roots)    Performs a garbage collection.
  65                                 'get_roots' is called to find all the
  66                                 roots that the system knows about.
  67
  68    StgClosure                   Called by get_roots on each root.
  69    MarkRoot(StgClosure *p)      Returns the new location of the root.
  70    -------------------------------------------------------------------------- */
  71
  72 extern void   GarbageCollect(void (*get_roots)(void));
  73 extern StgClosure *MarkRoot(StgClosure *p);
  74
  75 /* -----------------------------------------------------------------------------
  76    Generational garbage collection support
  77
  78    RecordMutable(StgPtr p)       Informs the garbage collector that a
  79                                  previously immutable object has
  80                                  become (permanently) mutable.  Used
  81                                  by thawArray and similar.
  82
  83    UpdateWithIndirection(p1,p2)  Updates the object at p1 with an
  84                                  indirection pointing to p2.  This is
  85                                  normally called for objects in an old
  86                                  generation (>0) when they are updated.
  87
  88    -------------------------------------------------------------------------- */
  89
  90 extern void RecordMutable(StgPtr p);
  91 extern void UpdateWithIndirection(StgPtr p1, StgPtr p2);
  92
  93 /* -----------------------------------------------------------------------------
  94    The CAF list - used to let us revert CAFs
  95
  96    -------------------------------------------------------------------------- */
  97
  98 StgCAF* enteredCAFs;
  99
 100 #endif STORAGE_H
 101