X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fincludes%2FInfoTables.h;h=2c300cf2a3155889927f2603516d06e0a776f117;hb=6a02dd25682e76484d2505ec7139948e6a32b9ee;hp=f9b97eb402cee3c3a3aca24c0f063b09db64eb78;hpb=20fc2f0ced64a12d8e44956931b2ac341ed2186f;p=ghc-hetmet.git diff --git a/ghc/includes/InfoTables.h b/ghc/includes/InfoTables.h index f9b97eb..2c300cf 100644 --- a/ghc/includes/InfoTables.h +++ b/ghc/includes/InfoTables.h @@ -1,7 +1,7 @@ /* ---------------------------------------------------------------------------- - * $Id: InfoTables.h,v 1.21 2001/03/22 03:51:09 hwloidl Exp $ + * $Id: InfoTables.h,v 1.31 2003/11/14 09:27:00 stolz Exp $ * - * (c) The GHC Team, 1998-1999 + * (c) The GHC Team, 1998-2002 * * Info Tables * @@ -14,21 +14,11 @@ Profiling info -------------------------------------------------------------------------- */ -#ifdef PROFILING - typedef struct { char *closure_type; char *closure_desc; } StgProfInfo; -#else /* !PROFILING */ - -typedef struct { - /* empty */ -} StgProfInfo; - -#endif /* PROFILING */ - /* ----------------------------------------------------------------------------- Parallelism info -------------------------------------------------------------------------- */ @@ -42,13 +32,7 @@ typedef struct { StgInfoTable *rbh_infoptr; /* infoptr to the RBH */ } StgParInfo; -#else /* !PAR */ - -typedef struct { - /* empty */ -} StgParInfo; - -#endif /* PAR */ +#endif /* 0 */ /* Copied from ghc-0.29; ToDo: check this code -- HWL @@ -98,6 +82,16 @@ typedef struct { #endif /* ----------------------------------------------------------------------------- + Ticky info + -------------------------------------------------------------------------- */ + +#if defined(SUPPORTS_EMPTY_STRUCTS) +typedef struct { + /* empty */ +} StgTickyInfo; +#endif + +/* ----------------------------------------------------------------------------- Debugging info -------------------------------------------------------------------------- */ @@ -109,12 +103,18 @@ typedef struct { #else /* !DEBUG_CLOSURE */ -typedef struct { +# if defined(SUPPORTS_EMPTY_STRUCTS) +typedef struct StgDebugInfo { /* empty */ } StgDebugInfo; +# endif #endif /* DEBUG_CLOSURE */ +/* ----------------------------------------------------------------------------- + Closure flags + -------------------------------------------------------------------------- */ + /* The type flags provide quick access to certain properties of a closure. */ #define _HNF (1<<0) /* head normal form? */ @@ -163,87 +163,181 @@ extern StgWord16 closure_flags[]; #define ip_IND(ip) ( ipFlags(ip) & _IND) /* ----------------------------------------------------------------------------- - Info Tables + Bitmaps + + These are used to describe the pointerhood of a sequence of words + (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). -------------------------------------------------------------------------- */ -/* A large bitmap. Small 32-bit ones live in the info table, but sometimes - * 32 bits isn't enough and we have to generate a larger one. (sizes - * differ for 64-bit machines. - */ +/* + Small bitmaps: for a small bitmap, we store the size and bitmap in + the same word, using the following macros. If the bitmap doesn't + fit in a single word, we use a pointer to an StgLargeBitmap below. +*/ +#define MK_SMALL_BITMAP(size,bits) (((bits)<> BITMAP_BITS_SHIFT) +/* + A large bitmap. +*/ typedef struct { StgWord size; - StgWord bitmap[0]; + StgWord bitmap[FLEXIBLE_ARRAY]; } StgLargeBitmap; -/* - * Stuff describing the closure layout. Well, actually, it might - * contain the selector index for a THUNK_SELECTOR. If we're on a - * 64-bit architecture then we can enlarge some of these fields, since - * the union contains a pointer field. - */ +/* ----------------------------------------------------------------------------- + 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 + ------------------------------------------------------------------------- */ + +/* + Stuff describing the closure layout. Well, actually, it might + contain the selector index for a THUNK_SELECTOR. This union is one + word long. +*/ typedef union { - struct { -#if SIZEOF_VOID_P == 8 - StgWord32 ptrs; /* number of pointers */ - StgWord32 nptrs; /* number of non-pointers */ -#else - StgWord16 ptrs; /* number of pointers */ - StgWord16 nptrs; /* number of non-pointers */ -#endif - } payload; + struct { /* Heap closure payload layout: */ + StgHalfWord ptrs; /* number of pointers */ + StgHalfWord nptrs; /* number of non-pointers */ + } payload; + + StgWord bitmap; /* word-sized bit pattern describing */ + /* a stack frame: see below */ + + StgLargeBitmap* large_bitmap; /* pointer to large bitmap structure */ + + StgWord selector_offset; /* used in THUNK_SELECTORs */ - StgWord bitmap; /* bit pattern, 1 = pointer, 0 = non-pointer */ - StgWord selector_offset; /* used in THUNK_SELECTORs */ - StgLargeBitmap* large_bitmap; /* pointer to large bitmap structure */ - } StgClosureInfo; + /* - * Info tables. All info tables are the same type, to simplify code - * generation. However, the mangler removes any unused SRT fields - * from the asm to save space (convention: if srt_len is zero, or the - * type is a CONSTR_ type, then the SRT field isn't present. - */ + The "standard" part of an info table. Every info table has this bit. +*/ +typedef struct _StgInfoTable { -typedef StgClosure* StgSRT[]; +#ifndef TABLES_NEXT_TO_CODE + StgFunPtr entry; // pointer to the entry code +#endif -typedef struct _StgInfoTable { - StgSRT *srt; /* pointer to the SRT table */ #if defined(PAR) || defined(GRAN) struct _StgInfoTable *rbh_infoptr; #endif #ifdef PROFILING StgProfInfo prof; #endif -#ifdef DEBUG_CLOSURE - StgDebugInfo debug; +#ifdef TICKY + MAYBE_EMPTY_STRUCT(StgTickyInfo,ticky) #endif - StgClosureInfo layout; /* closure layout info (pointer-sized) */ -#if SIZEOF_VOID_P == 8 - StgWord32 type; /* } These 2 elements fit into 64 bits */ - StgWord32 srt_len; /* } */ -#else - StgWord type : 16; /* } These 2 elements fit into 32 bits */ - StgWord srt_len : 16; /* } */ +#ifdef DEBUG_CLOSURE + MAYBE_EMPTY_STRUCT(StgDebugInfo,debug) #endif + + StgClosureInfo layout; /* closure layout info (one word) */ + + StgHalfWord type; /* closure type */ + StgHalfWord srt_bitmap; /* number of entries in SRT (or constructor tag) */ + #ifdef TABLES_NEXT_TO_CODE - StgCode code[0]; -#else - StgFunPtr entry; - StgFunPtr vector[0]; + StgCode code[FLEXIBLE_ARRAY]; #endif } StgInfoTable; -/* Info tables are read-only, therefore we uniformly declare them with - * C's const attribute. This isn't just a nice thing to do: it's - * necessary because the garbage collector has to distinguish between - * closure pointers and info table pointers when traversing the - * stack. We distinguish the two by checking whether the pointer is - * into text-space or not. - */ - -#define INFO_TBL_CONST const + +/* ----------------------------------------------------------------------------- + Function info tables + + This is the general form of function info tables. The compiler + will omit some of the fields in common cases: + + - If fun_type is not ARG_GEN or ARG_GEN_BIG, then the slow_apply + and bitmap fields may be left out (they are at the end, so omitting + them doesn't affect the layout). + + - 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 */ + StgWord bitmap; /* arg ptr/nonptr bitmap */ + StgSRT *srt; /* pointer to the SRT table */ + StgHalfWord fun_type; /* function type */ + StgHalfWord arity; /* function arity */ + StgInfoTable i; +#else + StgInfoTable i; + 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 */ +#endif +} StgFunInfoTable; + +/* ----------------------------------------------------------------------------- + Return info tables + -------------------------------------------------------------------------- */ + +/* When info tables are laid out backwards, we can omit the SRT + 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 */ +#if defined(TABLES_NEXT_TO_CODE) + StgInfoTable i; +#endif +#if !defined(TABLES_NEXT_TO_CODE) + StgFunPtr vector[FLEXIBLE_ARRAY]; +#endif +} StgRetInfoTable; + +/* ----------------------------------------------------------------------------- + Thunk info tables + -------------------------------------------------------------------------- */ + +/* When info tables are laid out backwards, we can omit the SRT + pointer iff srt_bitmap is zero. */ + +typedef struct _StgThunkInfoTable { +#if !defined(TABLES_NEXT_TO_CODE) + StgInfoTable i; +#endif + StgSRT *srt; /* pointer to the SRT table */ +#if defined(TABLES_NEXT_TO_CODE) + StgInfoTable i; +#endif +} StgThunkInfoTable; #endif /* INFOTABLES_H */