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+/* -----------------------------------------------------------------------------
+ *
+ * (c) The GHC Team, 1998-2004
+ *
+ * Stable Pointers: A stable pointer is represented as an index into
+ * the stable pointer table in the low BITS_PER_WORD-8 bits with a
+ * weight in the upper 8 bits.
+ *
+ * SUP: StgStablePtr used to be a synonym for StgWord, but stable pointers
+ * are guaranteed to be void* on the C-side, so we have to do some occasional
+ * casting. Size is not a matter, because StgWord is always the same size as
+ * a void*.
+ *
+ * ---------------------------------------------------------------------------*/
+
+#ifndef STABLE_H
+#define STABLE_H
+
+/* -----------------------------------------------------------------------------
+ External C Interface
+ -------------------------------------------------------------------------- */
+
+extern StgPtr deRefStablePtr(StgStablePtr stable_ptr);
+extern void freeStablePtr(StgStablePtr sp);
+extern StgStablePtr splitStablePtr(StgStablePtr sp);
+extern StgStablePtr getStablePtr(StgPtr p);
+
+/* -----------------------------------------------------------------------------
+ PRIVATE from here.
+ -------------------------------------------------------------------------- */
+
+typedef struct {
+ StgPtr addr; /* Haskell object, free list, or NULL */
+ StgPtr old; /* old Haskell object, used during GC */
+ StgWord ref; /* used for reference counting */
+ StgClosure *sn_obj; /* the StableName object (or NULL) */
+} snEntry;
+
+extern DLL_IMPORT_RTS snEntry *stable_ptr_table;
+
+extern void freeStablePtr(StgStablePtr sp);
+
+#if defined(__GNUC__)
+# ifndef RTS_STABLE_C
+extern inline
+# endif
+StgPtr deRefStablePtr(StgStablePtr sp)
+{
+ ASSERT(stable_ptr_table[(StgWord)sp].ref > 0);
+ return stable_ptr_table[(StgWord)sp].addr;
+}
+#else
+/* No support for 'extern inline' */
+extern StgPtr deRefStablePtr(StgStablePtr sp);
+#endif
+
+extern void initStablePtrTable ( void );
+extern void enlargeStablePtrTable ( void );
+extern StgWord lookupStableName ( StgPtr p );
+
+extern void markStablePtrTable ( evac_fn evac );
+extern void threadStablePtrTable ( evac_fn evac );
+extern void gcStablePtrTable ( void );
+extern void updateStablePtrTable ( rtsBool full );
+
+#endif