/* -----------------------------------------------------------------------------
- * $Id: Block.h,v 1.2 1998/12/02 13:20:53 simonm Exp $
+ * $Id: Block.h,v 1.7 2000/04/05 14:26:31 panne Exp $
+ *
+ * (c) The GHC Team, 1998-1999
*
* Block structure for the storage manager
*
StgPtr free; /* first free byte of memory */
struct _bdescr *link; /* used for chaining blocks together */
struct _bdescr *back; /* used (occasionally) for doubly-linked lists*/
- StgNat32 gen; /* generation */
- StgNat32 step; /* step */
- StgNat32 blocks; /* no. of blocks (if grp head, 0 otherwise) */
+ struct _generation *gen; /* generation */
+ struct _step *step; /* step */
+ StgWord32 blocks; /* no. of blocks (if grp head, 0 otherwise) */
+ StgWord32 evacuated; /* block is in to-space */
#if SIZEOF_VOID_P == 8
- StgNat32 _padding[5];
+ StgWord32 _padding[2];
#else
- StgNat32 _padding[1];
+ StgWord32 _padding[0];
#endif
} bdescr;
#define BDESCR_SHIFT 5
#endif
+/* Finding the block descriptor for a given block -------------------------- */
+
+static inline bdescr *Bdescr(StgPtr p)
+{
+ return (bdescr *)
+ ((((W_)p & MBLOCK_MASK & ~BLOCK_MASK) >> (BLOCK_SHIFT-BDESCR_SHIFT))
+ | ((W_)p & ~MBLOCK_MASK)
+ );
+}
+
/* Useful Macros ------------------------------------------------------------ */
/* Offset of first real data block in a megablock */
#define BLOCKS_TO_MBLOCKS(n) \
(1 + (W_)MBLOCK_ROUND_UP((n-BLOCKS_PER_MBLOCK) * BLOCK_SIZE) / MBLOCK_SIZE)
-#endif BLOCK_H
+#endif /* BLOCK_H */