1 /* ----------------------------------------------------------------------------
2 * $Id: InfoTables.h,v 1.33 2004/08/13 13:09:17 simonmar Exp $
4 * (c) The GHC Team, 1998-2002
8 * -------------------------------------------------------------------------- */
13 /* -----------------------------------------------------------------------------
15 -------------------------------------------------------------------------- */
22 /* -----------------------------------------------------------------------------
24 -------------------------------------------------------------------------- */
26 #if 0 && (defined(PAR) || defined(GRAN))
29 // ToDo: use this in StgInfoTable (mutually recursive) -- HWL
32 StgInfoTable *rbh_infoptr; /* infoptr to the RBH */
38 Copied from ghc-0.29; ToDo: check this code -- HWL
40 In the parallel system, all updatable closures have corresponding
41 revertible black holes. When we are assembly-mangling, we guarantee
42 that the revertible black hole code precedes the normal entry code, so
43 that the RBH info table resides at a fixed offset from the normal info
44 table. Otherwise, we add the RBH info table pointer to the end of the
45 normal info table and vice versa.
47 Currently has to use a !RBH_MAGIC_OFFSET setting.
48 Still todo: init of par.infoptr field in all infotables!!
51 #if defined(PAR) || defined(GRAN)
53 # ifdef RBH_MAGIC_OFFSET
55 # error magic offset not yet implemented
57 # define RBH_INFO_WORDS 0
58 # define INCLUDE_RBH_INFO(infoptr)
60 # define RBH_INFOPTR(infoptr) (((P_)infoptr) - RBH_MAGIC_OFFSET)
61 # define REVERT_INFOPTR(infoptr) (((P_)infoptr) + RBH_MAGIC_OFFSET)
65 # define RBH_INFO_WORDS 1
66 # define INCLUDE_RBH_INFO(info) rbh_infoptr : &(info)
68 # define RBH_INFOPTR(infoptr) (((StgInfoTable *)(infoptr))->rbh_infoptr)
69 # define REVERT_INFOPTR(infoptr) (((StgInfoTable *)(infoptr))->rbh_infoptr)
73 /* see ParallelRts.h */
75 //StgClosure *convertToRBH(StgClosure *closure);
77 //void convertFromRBH(StgClosure *closure);
79 //void convertToFetchMe(StgPtr closure, globalAddr *ga);
84 /* -----------------------------------------------------------------------------
86 -------------------------------------------------------------------------- */
88 #if defined(SUPPORTS_EMPTY_STRUCTS)
94 /* -----------------------------------------------------------------------------
96 -------------------------------------------------------------------------- */
104 #else /* !DEBUG_CLOSURE */
106 # if defined(SUPPORTS_EMPTY_STRUCTS)
107 typedef struct StgDebugInfo {
112 #endif /* DEBUG_CLOSURE */
114 /* -----------------------------------------------------------------------------
116 -------------------------------------------------------------------------- */
118 /* The type flags provide quick access to certain properties of a closure. */
120 #define _HNF (1<<0) /* head normal form? */
121 #define _BTM (1<<1) /* bitmap-style layout? */
122 #define _NS (1<<2) /* non-sparkable */
123 #define _STA (1<<3) /* static? */
124 #define _THU (1<<4) /* thunk? */
125 #define _MUT (1<<5) /* mutable? */
126 #define _UPT (1<<6) /* unpointed? */
127 #define _SRT (1<<7) /* has an SRT? */
128 #define _IND (1<<8) /* is an indirection? */
130 #define isSTATIC(flags) ((flags) &_STA)
131 #define isMUTABLE(flags) ((flags) &_MUT)
132 #define isBITMAP(flags) ((flags) &_BTM)
133 #define isTHUNK(flags) ((flags) &_THU)
134 #define isUNPOINTED(flags) ((flags) &_UPT)
135 #define hasSRT(flags) ((flags) &_SRT)
137 extern StgWord16 closure_flags[];
139 #define closureFlags(c) (closure_flags[get_itbl(c)->type])
141 #define closure_HNF(c) ( closureFlags(c) & _HNF)
142 #define closure_BITMAP(c) ( closureFlags(c) & _BTM)
143 #define closure_NON_SPARK(c) ( (closureFlags(c) & _NS))
144 #define closure_SHOULD_SPARK(c) (!(closureFlags(c) & _NS))
145 #define closure_STATIC(c) ( closureFlags(c) & _STA)
146 #define closure_THUNK(c) ( closureFlags(c) & _THU)
147 #define closure_MUTABLE(c) ( closureFlags(c) & _MUT)
148 #define closure_UNPOINTED(c) ( closureFlags(c) & _UPT)
149 #define closure_SRT(c) ( closureFlags(c) & _SRT)
150 #define closure_IND(c) ( closureFlags(c) & _IND)
152 /* same as above but for info-ptr rather than closure */
153 #define ipFlags(ip) (closure_flags[ip->type])
155 #define ip_HNF(ip) ( ipFlags(ip) & _HNF)
156 #define ip_BITMAP(ip) ( ipFlags(ip) & _BTM)
157 #define ip_SHOULD_SPARK(ip) (!(ipFlags(ip) & _NS))
158 #define ip_STATIC(ip) ( ipFlags(ip) & _STA)
159 #define ip_THUNK(ip) ( ipFlags(ip) & _THU)
160 #define ip_MUTABLE(ip) ( ipFlags(ip) & _MUT)
161 #define ip_UNPOINTED(ip) ( ipFlags(ip) & _UPT)
162 #define ip_SRT(ip) ( ipFlags(ip) & _SRT)
163 #define ip_IND(ip) ( ipFlags(ip) & _IND)
165 /* -----------------------------------------------------------------------------
168 These are used to describe the pointerhood of a sequence of words
169 (usually on the stack) to the garbage collector. The two primary
170 uses are for stack frames, and functions (where we need to describe
171 the layout of a PAP to the GC).
173 In these bitmaps: 0 == ptr, 1 == non-ptr.
174 -------------------------------------------------------------------------- */
177 // Small bitmaps: for a small bitmap, we store the size and bitmap in
178 // the same word, using the following macros. If the bitmap doesn't
179 // fit in a single word, we use a pointer to an StgLargeBitmap below.
181 #define MK_SMALL_BITMAP(size,bits) (((bits)<<BITMAP_BITS_SHIFT) | (size))
183 #define BITMAP_SIZE(bitmap) ((bitmap) & BITMAP_SIZE_MASK)
184 #define BITMAP_BITS(bitmap) ((bitmap) >> BITMAP_BITS_SHIFT)
191 StgWord bitmap[FLEXIBLE_ARRAY];
194 /* -----------------------------------------------------------------------------
195 SRTs (Static Reference Tables)
197 These tables are used to keep track of the static objects referred
198 to by the code for a closure or stack frame, so that we can follow
199 static data references from code and thus accurately
200 garbage-collect CAFs.
201 -------------------------------------------------------------------------- */
203 // An SRT is just an array of closure pointers:
204 typedef StgClosure* StgSRT[];
206 // Each info table refers to some subset of the closure pointers in an
207 // SRT. It does this using a pair of an StgSRT pointer and a
208 // half-word bitmap. If the half-word bitmap isn't large enough, then
209 // we fall back to a large SRT, including an unbounded bitmap. If the
210 // half-word bitmap is set to all ones (0xffff), then the StgSRT
211 // pointer instead points to an StgLargeSRT:
212 typedef struct StgLargeSRT_ {
217 /* ----------------------------------------------------------------------------
219 ------------------------------------------------------------------------- */
222 // Stuff describing the closure layout. Well, actually, it might
223 // contain the selector index for a THUNK_SELECTOR. This union is one
227 struct { // Heap closure payload layout:
228 StgHalfWord ptrs; // number of pointers
229 StgHalfWord nptrs; // number of non-pointers
232 StgWord bitmap; // word-sized bit pattern describing
233 // a stack frame: see below
235 StgLargeBitmap* large_bitmap; // pointer to large bitmap structure
237 StgWord selector_offset; // used in THUNK_SELECTORs
243 // The "standard" part of an info table. Every info table has this bit.
245 typedef struct _StgInfoTable {
247 #ifndef TABLES_NEXT_TO_CODE
248 StgFunPtr entry; // pointer to the entry code
251 #if defined(PAR) || defined(GRAN)
252 struct _StgInfoTable *rbh_infoptr;
258 MAYBE_EMPTY_STRUCT(StgTickyInfo,ticky)
261 MAYBE_EMPTY_STRUCT(StgDebugInfo,debug)
264 StgClosureInfo layout; // closure layout info (one word)
266 StgHalfWord type; // closure type
267 StgHalfWord srt_bitmap; // number of entries in SRT (or constructor tag)
269 #ifdef TABLES_NEXT_TO_CODE
270 StgCode code[FLEXIBLE_ARRAY];
275 /* -----------------------------------------------------------------------------
278 This is the general form of function info tables. The compiler
279 will omit some of the fields in common cases:
281 - If fun_type is not ARG_GEN or ARG_GEN_BIG, then the slow_apply
282 and bitmap fields may be left out (they are at the end, so omitting
283 them doesn't affect the layout).
285 - If srt_bitmap (in the std info table part) is zero, then the srt
286 field may be omitted. This only applies if the slow_apply and
287 bitmap fields have also been omitted.
288 -------------------------------------------------------------------------- */
290 typedef struct _StgFunInfoExtraRev {
291 StgFun *slow_apply; // apply to args on the stack
292 StgWord bitmap; // arg ptr/nonptr bitmap
293 StgSRT *srt; // pointer to the SRT table
294 StgHalfWord fun_type; // function type
295 StgHalfWord arity; // function arity
296 } StgFunInfoExtraRev;
298 typedef struct _StgFunInfoExtraFwd {
299 StgHalfWord fun_type; // function type
300 StgHalfWord arity; // function arity
301 StgSRT *srt; // pointer to the SRT table
302 StgWord bitmap; // arg ptr/nonptr bitmap
303 StgFun *slow_apply; // apply to args on the stack
304 } StgFunInfoExtraFwd;
307 #if defined(TABLES_NEXT_TO_CODE)
308 StgFunInfoExtraRev f;
312 StgFunInfoExtraFwd f;
316 /* -----------------------------------------------------------------------------
318 -------------------------------------------------------------------------- */
320 // When info tables are laid out backwards, we can omit the SRT
321 // pointer iff srt_bitmap is zero.
324 #if defined(TABLES_NEXT_TO_CODE)
325 StgSRT *srt; // pointer to the SRT table
329 StgSRT *srt; // pointer to the SRT table
330 StgFunPtr vector[FLEXIBLE_ARRAY];
334 /* -----------------------------------------------------------------------------
336 -------------------------------------------------------------------------- */
338 // When info tables are laid out backwards, we can omit the SRT
339 // pointer iff srt_bitmap is zero.
341 typedef struct _StgThunkInfoTable {
342 #if !defined(TABLES_NEXT_TO_CODE)
345 StgSRT *srt; // pointer to the SRT table
346 #if defined(TABLES_NEXT_TO_CODE)
351 #endif /* INFOTABLES_H */