Reorganisation of the source tree

[ghc-hetmet.git] / includes / Stable.h

diff --git a/includes/Stable.h b/includes/Stable.h
new file mode 100644 (file)
index 0000000..ca2e721
--- /dev/null
+++ b/includes/Stable.h
@@ -0,0 +1,66 @@
+/* -----------------------------------------------------------------------------
+ *
+ * (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