X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fincludes%2FInfoTables.h;h=8677e90908dc8fa80a4c91b434e7192da9a2bca4;hb=8504635323bc4c2d7ade98771a4e281c2d56761c;hp=97c3bec70b5b0b6c61edb816a868fdfb6660e620;hpb=0bffc410964e1688ad80d277d53400659e697ab5;p=ghc-hetmet.git diff --git a/ghc/includes/InfoTables.h b/ghc/includes/InfoTables.h index 97c3bec..8677e90 100644 --- a/ghc/includes/InfoTables.h +++ b/ghc/includes/InfoTables.h @@ -1,5 +1,5 @@ /* ---------------------------------------------------------------------------- - * $Id: InfoTables.h,v 1.28 2002/12/11 15:36:37 simonmar Exp $ + * $Id: InfoTables.h,v 1.35 2004/11/08 12:26:55 simonmar Exp $ * * (c) The GHC Team, 1998-2002 * @@ -83,11 +83,9 @@ typedef struct { /* ----------------------------------------------------------------------------- Ticky info - -------------------------------------------------------------------------- */ -typedef struct { - /* empty */ -} StgTickyInfo; + There is no ticky-specific stuff in an info table at this time. + -------------------------------------------------------------------------- */ /* ----------------------------------------------------------------------------- Debugging info @@ -101,9 +99,7 @@ typedef struct { #else /* !DEBUG_CLOSURE */ -typedef struct { - /* empty */ -} StgDebugInfo; +// There is no DEBUG-specific stuff in an info table at this time. #endif /* DEBUG_CLOSURE */ @@ -165,6 +161,8 @@ extern StgWord16 closure_flags[]; (usually on the stack) to the garbage collector. The two primary uses are for stack frames, and functions (where we need to describe the layout of a PAP to the GC). + + In these bitmaps: 0 == ptr, 1 == non-ptr. -------------------------------------------------------------------------- */ // @@ -185,6 +183,29 @@ typedef struct { StgWord bitmap[FLEXIBLE_ARRAY]; } StgLargeBitmap; +/* ----------------------------------------------------------------------------- + SRTs (Static Reference Tables) + + These tables are used to keep track of the static objects referred + to by the code for a closure or stack frame, so that we can follow + static data references from code and thus accurately + garbage-collect CAFs. + -------------------------------------------------------------------------- */ + +// An SRT is just an array of closure pointers: +typedef StgClosure* StgSRT[]; + +// Each info table refers to some subset of the closure pointers in an +// SRT. It does this using a pair of an StgSRT pointer and a +// half-word bitmap. If the half-word bitmap isn't large enough, then +// we fall back to a large SRT, including an unbounded bitmap. If the +// half-word bitmap is set to all ones (0xffff), then the StgSRT +// pointer instead points to an StgLargeSRT: +typedef struct StgLargeSRT_ { + StgSRT *srt; + StgLargeBitmap l; +} StgLargeSRT; + /* ---------------------------------------------------------------------------- Info Tables ------------------------------------------------------------------------- */ @@ -203,7 +224,11 @@ typedef union { StgWord bitmap; // word-sized bit pattern describing // a stack frame: see below +#ifndef TABLES_NEXT_TO_CODE StgLargeBitmap* large_bitmap; // pointer to large bitmap structure +#else + StgWord large_bitmap_offset; // offset from info table to large bitmap structure +#endif StgWord selector_offset; // used in THUNK_SELECTORs @@ -211,11 +236,6 @@ typedef union { // -// An SRT. -// -typedef StgClosure* StgSRT[]; - -// // The "standard" part of an info table. Every info table has this bit. // typedef struct _StgInfoTable { @@ -231,16 +251,16 @@ typedef struct _StgInfoTable { StgProfInfo prof; #endif #ifdef TICKY - StgTickyInfo ticky; + // Ticky-specific stuff would go here. #endif #ifdef DEBUG_CLOSURE - StgDebugInfo debug; + // Debug-specific stuff would go here. #endif StgClosureInfo layout; // closure layout info (one word) StgHalfWord type; // closure type - StgHalfWord srt_len; // number of entries in SRT (or constructor tag) + StgHalfWord srt_bitmap; // number of entries in SRT (or constructor tag) #ifdef TABLES_NEXT_TO_CODE StgCode code[FLEXIBLE_ARRAY]; @@ -258,26 +278,34 @@ typedef struct _StgInfoTable { and bitmap fields may be left out (they are at the end, so omitting them doesn't affect the layout). - - If srt_len (in the std info table part) is zero, then the srt + - If srt_bitmap (in the std info table part) is zero, then the srt field may be omitted. This only applies if the slow_apply and bitmap fields have also been omitted. -------------------------------------------------------------------------- */ -typedef struct _StgFunInfoTable { -#if defined(TABLES_NEXT_TO_CODE) - StgFun *slow_apply; // apply to args on the stack +typedef struct _StgFunInfoExtraRev { + StgWord slow_apply_offset; // apply to args on the stack StgWord bitmap; // arg ptr/nonptr bitmap - StgSRT *srt; // pointer to the SRT table + StgWord srt_offset; // pointer to the SRT table StgHalfWord fun_type; // function type StgHalfWord arity; // function arity - StgInfoTable i; -#else - StgInfoTable i; +} StgFunInfoExtraRev; + +typedef struct _StgFunInfoExtraFwd { StgHalfWord fun_type; // function type StgHalfWord arity; // function arity StgSRT *srt; // pointer to the SRT table StgWord bitmap; // arg ptr/nonptr bitmap StgFun *slow_apply; // apply to args on the stack +} StgFunInfoExtraFwd; + +typedef struct { +#if defined(TABLES_NEXT_TO_CODE) + StgFunInfoExtraRev f; + StgInfoTable i; +#else + StgInfoTable i; + StgFunInfoExtraFwd f; #endif } StgFunInfoTable; @@ -286,17 +314,15 @@ typedef struct _StgFunInfoTable { -------------------------------------------------------------------------- */ // When info tables are laid out backwards, we can omit the SRT -// pointer iff srt_len is zero. +// pointer iff srt_bitmap is zero. -typedef struct _StgRetInfoTable { -#if !defined(TABLES_NEXT_TO_CODE) - StgInfoTable i; -#endif - StgSRT *srt; // pointer to the SRT table +typedef struct { #if defined(TABLES_NEXT_TO_CODE) + StgWord srt_offset; // offset to the SRT table StgInfoTable i; -#endif -#if !defined(TABLES_NEXT_TO_CODE) +#else + StgInfoTable i; + StgSRT *srt; // pointer to the SRT table StgFunPtr vector[FLEXIBLE_ARRAY]; #endif } StgRetInfoTable; @@ -306,16 +332,56 @@ typedef struct _StgRetInfoTable { -------------------------------------------------------------------------- */ // When info tables are laid out backwards, we can omit the SRT -// pointer iff srt_len is zero. +// pointer iff srt_bitmap is zero. typedef struct _StgThunkInfoTable { #if !defined(TABLES_NEXT_TO_CODE) StgInfoTable i; #endif +#if defined(TABLES_NEXT_TO_CODE) + StgWord srt_offset; // offset to the SRT table +#else StgSRT *srt; // pointer to the SRT table +#endif #if defined(TABLES_NEXT_TO_CODE) StgInfoTable i; #endif } StgThunkInfoTable; + +/* ----------------------------------------------------------------------------- + Accessor macros for fields that might be offsets (C version) + -------------------------------------------------------------------------- */ + +// GET_SRT(info) +// info must be a Stg[Ret|Thunk]InfoTable* (an info table that has a SRT) +#ifdef TABLES_NEXT_TO_CODE +#define GET_SRT(info) ((StgSRT*) (((StgWord) ((info)+1)) + (info)->srt_offset)) +#else +#define GET_SRT(info) ((info)->srt) +#endif + +// GET_FUN_SRT(info) +// info must be a StgFunInfoTable* +#ifdef TABLES_NEXT_TO_CODE +#define GET_FUN_SRT(info) ((StgSRT*) (((StgWord) ((info)+1)) + (info)->f.srt_offset)) +#else +#define GET_FUN_SRT(info) ((info)->f.srt) +#endif + +#ifdef TABLES_NEXT_TO_CODE +#define GET_LARGE_BITMAP(info) ((StgLargeBitmap*) (((StgWord) ((info)+1)) \ + + (info)->layout.large_bitmap_offset)) +#else +#define GET_LARGE_BITMAP(info) ((info)->layout.large_bitmap) +#endif + +#ifdef TABLES_NEXT_TO_CODE +#define GET_FUN_LARGE_BITMAP(info) ((StgLargeBitmap*) (((StgWord) ((info)+1)) \ + + (info)->f.bitmap)) +#else +#define GET_FUN_LARGE_BITMAP(info) ((StgLargeBitmap*) ((info)->f.bitmap)) +#endif + + #endif /* INFOTABLES_H */