X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fincludes%2FStable.h;h=12056f9974885eac3141c6e4b26385ad9f59db14;hb=791d890ca039ce45704b879b292069ddc5821dc0;hp=960ac271800797ce98ee563305488187f257d769;hpb=21462c00b3241f15de3b145ac92ee5b266b5733a;p=ghc-hetmet.git diff --git a/ghc/includes/Stable.h b/ghc/includes/Stable.h index 960ac27..12056f9 100644 --- a/ghc/includes/Stable.h +++ b/ghc/includes/Stable.h @@ -1,12 +1,22 @@ /* ----------------------------------------------------------------------------- - * $Id: Stable.h,v 1.4 1999/03/02 19:44:16 sof Exp $ + * $Id: Stable.h,v 1.12 2001/12/20 16:12:09 sewardj Exp $ * - * (c) The GHC Team, 1998-1999 + * (c) The GHC Team, 1998-2000 * - * Stable names and stable pointers + * 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 -------------------------------------------------------------------------- */ @@ -14,16 +24,16 @@ extern StgPtr deRefStablePtr(StgStablePtr stable_ptr); extern void freeStablePtr(StgStablePtr sp); extern StgStablePtr splitStablePtr(StgStablePtr sp); +extern StgStablePtr getStablePtr(StgPtr p); /* ----------------------------------------------------------------------------- PRIVATE from here. -------------------------------------------------------------------------- */ -extern StgStablePtr getStablePtr(StgPtr p); - typedef struct { StgPtr addr; /* Haskell object, free list, or NULL */ - StgWord weight; /* used for reference counting */ + StgPtr old; /* old Haskell object, used during GC */ + StgWord ref; /* used for reference counting */ StgClosure *sn_obj; /* the StableName object (or NULL) */ } snEntry; @@ -32,33 +42,17 @@ extern DLL_IMPORT_RTS snEntry *stable_ptr_free; extern DLL_IMPORT_RTS unsigned int SPT_size; +extern void freeStablePtr(StgStablePtr sp); + 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; + ASSERT(stable_ptr_table[(StgWord)sp].ref > 0); + return stable_ptr_table[(StgWord)sp].addr; } /* No deRefStableName, because the existence of a stable name doesn't * guarantee the existence of the object itself. */ + +#endif