[project @ 1999-01-26 14:04:46 by simonm]

add missing file.

ghc/includes/Stable.h

+/* -----------------------------------------------------------------------------
+ * $Id: Stable.h,v 1.1 1999/01/26 14:04:46 simonm Exp $
+ *
+ * Stable names and stable pointers
+ *
+ * ---------------------------------------------------------------------------*/
+
+/* -----------------------------------------------------------------------------
+   External C Interface
+   -------------------------------------------------------------------------- */
+
+extern StgPtr         deRefStablePtr(StgStablePtr stable_ptr);
+extern void           freeStablePtr(StgStablePtr sp);
+extern StgStablePtr   splitStablePtr(StgStablePtr sp);
+
+/* -----------------------------------------------------------------------------
+   PRIVATE from here.
+   -------------------------------------------------------------------------- */
+
+extern StgStablePtr getStablePtr(StgPtr p);
+
+typedef struct { 
+  StgPtr  addr;			/* either Haskell object or free list */
+  StgWord weight;		/* used for reference counting */
+  unsigned int keep;		/* set by the garbage collector */
+} snEntry;
+
+extern snEntry *stable_ptr_table;
+extern snEntry *stable_ptr_free;
+
+extern unsigned int SPT_size;
+
+extern inline StgPtr
+deRefStablePtr(StgStablePtr sp)
+{
+  ASSERT(stable_ptr_table[sp & ~STABLEPTR_WEIGHT_MASK].weight > 0);
+  return stable_ptr_table[sp & ~STABLEPTR_WEIGHT_MASK].addr;
+}
+
+extern inline void
+freeStablePtr(StgStablePtr sp)
+{
+  StgWord sn = sp & ~STABLEPTR_WEIGHT_MASK;
+  
+  ASSERT(sn < SPT_size
+	 && stable_ptr_table[sn].addr != NULL
+	 && stable_ptr_table[sn].weight > 0);
+  
+  stable_ptr_table[sn].weight += (sp & STABLEPTR_WEIGHT_MASK) >> STABLEPTR_WEIGHT_SHIFT;
+}
+
+extern inline StgStablePtr
+splitStablePtr(StgStablePtr sp)
+{
+  /* doesn't need access to the stable pointer table */
+  StgWord weight = (sp & STABLEPTR_WEIGHT_MASK) / 2;
+  return (sp & ~STABLEPTR_WEIGHT_MASK) + weight;
+}
+
+/* No deRefStableName, because the existence of a stable name doesn't
+ * guarantee the existence of the object itself.
+ */