1 /* ----------------------------------------------------------------------------
3 * (c) The GHC Team, 1998-2004
5 * Entry code for various built-in closure types.
7 * This file is written in a subset of C--, extended with various
8 * features specific to GHC. It is compiled by GHC directly. For the
9 * syntax of .cmm files, see the parser in ghc/compiler/cmm/CmmParse.y.
11 * --------------------------------------------------------------------------*/
15 import pthread_mutex_lock;
16 import ghczmprim_GHCziTypes_Czh_static_info;
17 import ghczmprim_GHCziTypes_Izh_static_info;
18 import EnterCriticalSection;
19 import LeaveCriticalSection;
21 /* ----------------------------------------------------------------------------
22 Support for the bytecode interpreter.
23 ------------------------------------------------------------------------- */
25 /* 9 bits of return code for constructors created by the interpreter. */
26 stg_interp_constr_entry
28 /* R1 points at the constructor */
29 jump %ENTRY_CODE(Sp(0));
32 /* Some info tables to be used when compiled code returns a value to
33 the interpreter, i.e. the interpreter pushes one of these onto the
34 stack before entering a value. What the code does is to
35 impedance-match the compiled return convention (in R1p/R1n/F1/D1 etc) to
36 the interpreter's convention (returned value is on top of stack),
37 and then cause the scheduler to enter the interpreter.
39 On entry, the stack (growing down) looks like this:
41 ptr to BCO holding return continuation
42 ptr to one of these info tables.
44 The info table code, both direct and vectored, must:
45 * push R1/F1/D1 on the stack, and its tag if necessary
46 * push the BCO (so it's now on the stack twice)
47 * Yield, ie, go to the scheduler.
49 Scheduler examines the t.o.s, discovers it is a BCO, and proceeds
50 directly to the bytecode interpreter. That pops the top element
51 (the BCO, containing the return continuation), and interprets it.
52 Net result: return continuation gets interpreted, with the
56 ptr to the info table just jumped thru
59 which is just what we want -- the "standard" return layout for the
62 Don't ask me how unboxed tuple returns are supposed to work. We
63 haven't got a good story about that yet.
66 INFO_TABLE_RET( stg_ctoi_R1p, RET_BCO)
70 Sp(0) = stg_enter_info;
71 jump stg_yield_to_interpreter;
75 * When the returned value is a pointer, but unlifted, in R1 ...
77 INFO_TABLE_RET( stg_ctoi_R1unpt, RET_BCO )
81 Sp(0) = stg_gc_unpt_r1_info;
82 jump stg_yield_to_interpreter;
86 * When the returned value is a non-pointer in R1 ...
88 INFO_TABLE_RET( stg_ctoi_R1n, RET_BCO )
92 Sp(0) = stg_gc_unbx_r1_info;
93 jump stg_yield_to_interpreter;
97 * When the returned value is in F1
99 INFO_TABLE_RET( stg_ctoi_F1, RET_BCO )
102 F_[Sp + WDS(1)] = F1;
103 Sp(0) = stg_gc_f1_info;
104 jump stg_yield_to_interpreter;
108 * When the returned value is in D1
110 INFO_TABLE_RET( stg_ctoi_D1, RET_BCO )
112 Sp_adj(-1) - SIZEOF_DOUBLE;
113 D_[Sp + WDS(1)] = D1;
114 Sp(0) = stg_gc_d1_info;
115 jump stg_yield_to_interpreter;
119 * When the returned value is in L1
121 INFO_TABLE_RET( stg_ctoi_L1, RET_BCO )
124 L_[Sp + WDS(1)] = L1;
125 Sp(0) = stg_gc_l1_info;
126 jump stg_yield_to_interpreter;
130 * When the returned value is a void
132 INFO_TABLE_RET( stg_ctoi_V, RET_BCO )
135 Sp(0) = stg_gc_void_info;
136 jump stg_yield_to_interpreter;
140 * Dummy info table pushed on the top of the stack when the interpreter
141 * should apply the BCO on the stack to its arguments, also on the
144 INFO_TABLE_RET( stg_apply_interp, RET_BCO )
146 /* Just in case we end up in here... (we shouldn't) */
147 jump stg_yield_to_interpreter;
150 /* ----------------------------------------------------------------------------
152 ------------------------------------------------------------------------- */
154 INFO_TABLE_FUN( stg_BCO, 4, 0, BCO, "BCO", "BCO", ARG_BCO )
156 /* entering a BCO means "apply it", same as a function */
159 Sp(0) = stg_apply_interp_info;
160 jump stg_yield_to_interpreter;
163 /* ----------------------------------------------------------------------------
164 Info tables for indirections.
166 SPECIALISED INDIRECTIONS: we have a specialised indirection for direct returns,
167 so that we can avoid entering
168 the object when we know it points directly to a value. The update
169 code (Updates.cmm) updates objects with the appropriate kind of
170 indirection. We only do this for young-gen indirections.
171 ------------------------------------------------------------------------- */
173 INFO_TABLE(stg_IND,1,0,IND,"IND","IND")
175 TICK_ENT_DYN_IND(); /* tick */
176 R1 = UNTAG(StgInd_indirectee(R1));
181 INFO_TABLE(stg_IND_direct,1,0,IND,"IND","IND")
183 TICK_ENT_DYN_IND(); /* tick */
184 R1 = StgInd_indirectee(R1);
186 jump %ENTRY_CODE(Sp(0));
189 INFO_TABLE(stg_IND_STATIC,1,0,IND_STATIC,"IND_STATIC","IND_STATIC")
191 TICK_ENT_STATIC_IND(); /* tick */
192 R1 = UNTAG(StgInd_indirectee(R1));
197 INFO_TABLE(stg_IND_PERM,1,0,IND_PERM,"IND_PERM","IND_PERM")
199 /* Don't add INDs to granularity cost */
201 /* Don't: TICK_ENT_STATIC_IND(Node); for ticky-ticky; this ind is
202 here only to help profiling */
204 #if defined(TICKY_TICKY) && !defined(PROFILING)
205 /* TICKY_TICKY && !PROFILING means PERM_IND *replaces* an IND, rather than
212 /* Enter PAP cost centre */
213 ENTER_CCS_PAP_CL(R1);
215 /* For ticky-ticky, change the perm_ind to a normal ind on first
216 * entry, so the number of ent_perm_inds is the number of *thunks*
217 * entered again, not the number of subsequent entries.
219 * Since this screws up cost centres, we die if profiling and
220 * ticky_ticky are on at the same time. KSW 1999-01.
224 # error Profiling and ticky-ticky do not mix at present!
225 # endif /* PROFILING */
226 StgHeader_info(R1) = stg_IND_info;
227 #endif /* TICKY_TICKY */
229 R1 = UNTAG(StgInd_indirectee(R1));
231 #if defined(TICKY_TICKY) && !defined(PROFILING)
238 /* ----------------------------------------------------------------------------
241 Entering a black hole normally causes a cyclic data dependency, but
242 in the concurrent world, black holes are synchronization points,
243 and they are turned into blocking queues when there are threads
244 waiting for the evaluation of the closure to finish.
245 ------------------------------------------------------------------------- */
247 INFO_TABLE(stg_BLACKHOLE,1,0,BLACKHOLE,"BLACKHOLE","BLACKHOLE")
249 W_ r, p, info, bq, msg, owner, bd;
251 TICK_ENT_DYN_IND(); /* tick */
254 p = StgInd_indirectee(R1);
255 if (GETTAG(p) != 0) {
257 jump %ENTRY_CODE(Sp(0));
260 info = StgHeader_info(p);
261 if (info == stg_IND_info) {
262 // This could happen, if e.g. we got a BLOCKING_QUEUE that has
263 // just been replaced with an IND by another thread in
264 // wakeBlockingQueue().
268 if (info == stg_TSO_info ||
269 info == stg_BLOCKING_QUEUE_CLEAN_info ||
270 info == stg_BLOCKING_QUEUE_DIRTY_info)
272 ("ptr" msg) = foreign "C" allocate(MyCapability() "ptr",
273 BYTES_TO_WDS(SIZEOF_MessageBlackHole)) [R1];
275 SET_HDR(msg, stg_MSG_BLACKHOLE_info, CCS_SYSTEM);
276 MessageBlackHole_tso(msg) = CurrentTSO;
277 MessageBlackHole_bh(msg) = R1;
279 (r) = foreign "C" messageBlackHole(MyCapability() "ptr", msg "ptr") [R1];
284 StgTSO_why_blocked(CurrentTSO) = BlockedOnBlackHole::I16;
285 StgTSO_block_info(CurrentTSO) = msg;
286 jump stg_block_blackhole;
296 INFO_TABLE(__stg_EAGER_BLACKHOLE,1,0,BLACKHOLE,"BLACKHOLE","BLACKHOLE")
298 jump ENTRY_LBL(stg_BLACKHOLE);
301 // CAF_BLACKHOLE is allocated when entering a CAF. The reason it is
302 // distinct from BLACKHOLE is so that we can tell the difference
303 // between an update frame on the stack that points to a CAF under
304 // evaluation, and one that points to a closure that is under
305 // evaluation by another thread (a BLACKHOLE). See threadPaused().
307 INFO_TABLE(stg_CAF_BLACKHOLE,1,0,BLACKHOLE,"BLACKHOLE","BLACKHOLE")
309 jump ENTRY_LBL(stg_BLACKHOLE);
312 INFO_TABLE(stg_BLOCKING_QUEUE_CLEAN,4,0,BLOCKING_QUEUE,"BLOCKING_QUEUE","BLOCKING_QUEUE")
313 { foreign "C" barf("BLOCKING_QUEUE_CLEAN object entered!") never returns; }
316 INFO_TABLE(stg_BLOCKING_QUEUE_DIRTY,4,0,BLOCKING_QUEUE,"BLOCKING_QUEUE","BLOCKING_QUEUE")
317 { foreign "C" barf("BLOCKING_QUEUE_DIRTY object entered!") never returns; }
320 /* ----------------------------------------------------------------------------
321 Whiteholes are used for the "locked" state of a closure (see lockClosure())
322 ------------------------------------------------------------------------- */
324 INFO_TABLE(stg_WHITEHOLE, 0,0, WHITEHOLE, "WHITEHOLE", "WHITEHOLE")
326 #if defined(THREADED_RTS)
331 // spin until the WHITEHOLE is updated
332 info = StgHeader_info(R1);
333 if (info == stg_WHITEHOLE_info) {
335 if (i == SPIN_COUNT) {
337 foreign "C" yieldThread() [R1];
341 jump %ENTRY_CODE(info);
343 foreign "C" barf("WHITEHOLE object entered!") never returns;
347 /* ----------------------------------------------------------------------------
348 Some static info tables for things that don't get entered, and
349 therefore don't need entry code (i.e. boxed but unpointed objects)
350 NON_ENTERABLE_ENTRY_CODE now defined at the beginning of the file
351 ------------------------------------------------------------------------- */
353 INFO_TABLE(stg_TSO, 0,0,TSO, "TSO", "TSO")
354 { foreign "C" barf("TSO object entered!") never returns; }
356 /* ----------------------------------------------------------------------------
359 Live weak pointers have a special closure type. Dead ones are just
360 nullary constructors (although they live on the heap - we overwrite
361 live weak pointers with dead ones).
362 ------------------------------------------------------------------------- */
364 INFO_TABLE(stg_WEAK,1,4,WEAK,"WEAK","WEAK")
365 { foreign "C" barf("WEAK object entered!") never returns; }
368 * It's important when turning an existing WEAK into a DEAD_WEAK
369 * (which is what finalizeWeak# does) that we don't lose the link
370 * field and break the linked list of weak pointers. Hence, we give
371 * DEAD_WEAK 5 non-pointer fields.
373 INFO_TABLE_CONSTR(stg_DEAD_WEAK,0,5,0,CONSTR,"DEAD_WEAK","DEAD_WEAK")
374 { foreign "C" barf("DEAD_WEAK object entered!") never returns; }
376 /* ----------------------------------------------------------------------------
379 This is a static nullary constructor (like []) that we use to mark an empty
380 finalizer in a weak pointer object.
381 ------------------------------------------------------------------------- */
383 INFO_TABLE_CONSTR(stg_NO_FINALIZER,0,0,0,CONSTR_NOCAF_STATIC,"NO_FINALIZER","NO_FINALIZER")
384 { foreign "C" barf("NO_FINALIZER object entered!") never returns; }
386 CLOSURE(stg_NO_FINALIZER_closure,stg_NO_FINALIZER);
388 /* ----------------------------------------------------------------------------
389 Stable Names are unlifted too.
390 ------------------------------------------------------------------------- */
392 INFO_TABLE(stg_STABLE_NAME,0,1,PRIM,"STABLE_NAME","STABLE_NAME")
393 { foreign "C" barf("STABLE_NAME object entered!") never returns; }
395 /* ----------------------------------------------------------------------------
398 There are two kinds of these: full and empty. We need an info table
399 and entry code for each type.
400 ------------------------------------------------------------------------- */
402 INFO_TABLE(stg_MVAR_CLEAN,3,0,MVAR_CLEAN,"MVAR","MVAR")
403 { foreign "C" barf("MVAR object entered!") never returns; }
405 INFO_TABLE(stg_MVAR_DIRTY,3,0,MVAR_DIRTY,"MVAR","MVAR")
406 { foreign "C" barf("MVAR object entered!") never returns; }
408 /* -----------------------------------------------------------------------------
410 -------------------------------------------------------------------------- */
412 INFO_TABLE(stg_TVAR, 2, 1, MUT_PRIM, "TVAR", "TVAR")
413 { foreign "C" barf("TVAR object entered!") never returns; }
415 INFO_TABLE(stg_TVAR_WATCH_QUEUE, 3, 0, MUT_PRIM, "TVAR_WATCH_QUEUE", "TVAR_WATCH_QUEUE")
416 { foreign "C" barf("TVAR_WATCH_QUEUE object entered!") never returns; }
418 INFO_TABLE(stg_ATOMIC_INVARIANT, 2, 1, MUT_PRIM, "ATOMIC_INVARIANT", "ATOMIC_INVARIANT")
419 { foreign "C" barf("ATOMIC_INVARIANT object entered!") never returns; }
421 INFO_TABLE(stg_INVARIANT_CHECK_QUEUE, 3, 0, MUT_PRIM, "INVARIANT_CHECK_QUEUE", "INVARIANT_CHECK_QUEUE")
422 { foreign "C" barf("INVARIANT_CHECK_QUEUE object entered!") never returns; }
424 INFO_TABLE(stg_TREC_CHUNK, 0, 0, TREC_CHUNK, "TREC_CHUNK", "TREC_CHUNK")
425 { foreign "C" barf("TREC_CHUNK object entered!") never returns; }
427 INFO_TABLE(stg_TREC_HEADER, 3, 1, MUT_PRIM, "TREC_HEADER", "TREC_HEADER")
428 { foreign "C" barf("TREC_HEADER object entered!") never returns; }
430 INFO_TABLE_CONSTR(stg_END_STM_WATCH_QUEUE,0,0,0,CONSTR_NOCAF_STATIC,"END_STM_WATCH_QUEUE","END_STM_WATCH_QUEUE")
431 { foreign "C" barf("END_STM_WATCH_QUEUE object entered!") never returns; }
433 INFO_TABLE_CONSTR(stg_END_INVARIANT_CHECK_QUEUE,0,0,0,CONSTR_NOCAF_STATIC,"END_INVARIANT_CHECK_QUEUE","END_INVARIANT_CHECK_QUEUE")
434 { foreign "C" barf("END_INVARIANT_CHECK_QUEUE object entered!") never returns; }
436 INFO_TABLE_CONSTR(stg_END_STM_CHUNK_LIST,0,0,0,CONSTR_NOCAF_STATIC,"END_STM_CHUNK_LIST","END_STM_CHUNK_LIST")
437 { foreign "C" barf("END_STM_CHUNK_LIST object entered!") never returns; }
439 INFO_TABLE_CONSTR(stg_NO_TREC,0,0,0,CONSTR_NOCAF_STATIC,"NO_TREC","NO_TREC")
440 { foreign "C" barf("NO_TREC object entered!") never returns; }
442 CLOSURE(stg_END_STM_WATCH_QUEUE_closure,stg_END_STM_WATCH_QUEUE);
444 CLOSURE(stg_END_INVARIANT_CHECK_QUEUE_closure,stg_END_INVARIANT_CHECK_QUEUE);
446 CLOSURE(stg_END_STM_CHUNK_LIST_closure,stg_END_STM_CHUNK_LIST);
448 CLOSURE(stg_NO_TREC_closure,stg_NO_TREC);
450 /* ----------------------------------------------------------------------------
452 ------------------------------------------------------------------------- */
454 // PRIM rather than CONSTR, because PRIM objects cannot be duplicated by the GC.
456 INFO_TABLE_CONSTR(stg_MSG_TRY_WAKEUP,2,0,0,PRIM,"MSG_TRY_WAKEUP","MSG_TRY_WAKEUP")
457 { foreign "C" barf("MSG_TRY_WAKEUP object entered!") never returns; }
459 INFO_TABLE_CONSTR(stg_MSG_THROWTO,4,0,0,PRIM,"MSG_THROWTO","MSG_THROWTO")
460 { foreign "C" barf("MSG_THROWTO object entered!") never returns; }
462 INFO_TABLE_CONSTR(stg_MSG_BLACKHOLE,3,0,0,PRIM,"MSG_BLACKHOLE","MSG_BLACKHOLE")
463 { foreign "C" barf("MSG_BLACKHOLE object entered!") never returns; }
465 // used to overwrite a MSG_THROWTO when the message has been used/revoked
466 INFO_TABLE_CONSTR(stg_MSG_NULL,1,0,0,PRIM,"MSG_NULL","MSG_NULL")
467 { foreign "C" barf("MSG_NULL object entered!") never returns; }
469 /* ----------------------------------------------------------------------------
472 This is a static nullary constructor (like []) that we use to mark the
473 end of a linked TSO queue.
474 ------------------------------------------------------------------------- */
476 INFO_TABLE_CONSTR(stg_END_TSO_QUEUE,0,0,0,CONSTR_NOCAF_STATIC,"END_TSO_QUEUE","END_TSO_QUEUE")
477 { foreign "C" barf("END_TSO_QUEUE object entered!") never returns; }
479 CLOSURE(stg_END_TSO_QUEUE_closure,stg_END_TSO_QUEUE);
481 /* ----------------------------------------------------------------------------
484 These come in two basic flavours: arrays of data (StgArrWords) and arrays of
485 pointers (StgArrPtrs). They all have a similar layout:
487 ___________________________
488 | Info | No. of | data....
490 ---------------------------
492 These are *unpointed* objects: i.e. they cannot be entered.
494 ------------------------------------------------------------------------- */
496 INFO_TABLE(stg_ARR_WORDS, 0, 0, ARR_WORDS, "ARR_WORDS", "ARR_WORDS")
497 { foreign "C" barf("ARR_WORDS object entered!") never returns; }
499 INFO_TABLE(stg_MUT_ARR_PTRS_CLEAN, 0, 0, MUT_ARR_PTRS_CLEAN, "MUT_ARR_PTRS_CLEAN", "MUT_ARR_PTRS_CLEAN")
500 { foreign "C" barf("MUT_ARR_PTRS_CLEAN object entered!") never returns; }
502 INFO_TABLE(stg_MUT_ARR_PTRS_DIRTY, 0, 0, MUT_ARR_PTRS_DIRTY, "MUT_ARR_PTRS_DIRTY", "MUT_ARR_PTRS_DIRTY")
503 { foreign "C" barf("MUT_ARR_PTRS_DIRTY object entered!") never returns; }
505 INFO_TABLE(stg_MUT_ARR_PTRS_FROZEN, 0, 0, MUT_ARR_PTRS_FROZEN, "MUT_ARR_PTRS_FROZEN", "MUT_ARR_PTRS_FROZEN")
506 { foreign "C" barf("MUT_ARR_PTRS_FROZEN object entered!") never returns; }
508 INFO_TABLE(stg_MUT_ARR_PTRS_FROZEN0, 0, 0, MUT_ARR_PTRS_FROZEN0, "MUT_ARR_PTRS_FROZEN0", "MUT_ARR_PTRS_FROZEN0")
509 { foreign "C" barf("MUT_ARR_PTRS_FROZEN0 object entered!") never returns; }
511 /* ----------------------------------------------------------------------------
513 ------------------------------------------------------------------------- */
515 INFO_TABLE(stg_MUT_VAR_CLEAN, 1, 0, MUT_VAR_CLEAN, "MUT_VAR_CLEAN", "MUT_VAR_CLEAN")
516 { foreign "C" barf("MUT_VAR_CLEAN object entered!") never returns; }
517 INFO_TABLE(stg_MUT_VAR_DIRTY, 1, 0, MUT_VAR_DIRTY, "MUT_VAR_DIRTY", "MUT_VAR_DIRTY")
518 { foreign "C" barf("MUT_VAR_DIRTY object entered!") never returns; }
520 /* ----------------------------------------------------------------------------
523 Entering this closure will just return to the address on the top of the
524 stack. Useful for getting a thread in a canonical form where we can
525 just enter the top stack word to start the thread. (see deleteThread)
526 * ------------------------------------------------------------------------- */
528 INFO_TABLE( stg_dummy_ret, 0, 0, CONSTR_NOCAF_STATIC, "DUMMY_RET", "DUMMY_RET")
530 jump %ENTRY_CODE(Sp(0));
532 CLOSURE(stg_dummy_ret_closure,stg_dummy_ret);
534 /* ----------------------------------------------------------------------------
536 ------------------------------------------------------------------------- */
538 INFO_TABLE_CONSTR(stg_MVAR_TSO_QUEUE,2,0,0,PRIM,"MVAR_TSO_QUEUE","MVAR_TSO_QUEUE")
539 { foreign "C" barf("MVAR_TSO_QUEUE object entered!") never returns; }
541 /* ----------------------------------------------------------------------------
542 CHARLIKE and INTLIKE closures.
544 These are static representations of Chars and small Ints, so that
545 we can remove dynamic Chars and Ints during garbage collection and
546 replace them with references to the static objects.
547 ------------------------------------------------------------------------- */
549 #if defined(__PIC__) && defined(mingw32_TARGET_OS)
551 * When sticking the RTS in a Windows DLL, we delay populating the
552 * Charlike and Intlike tables until load-time, which is only
553 * when we've got the real addresses to the C# and I# closures.
555 * -- this is currently broken BL 2009/11/14.
556 * we don't rewrite to static closures at all with Windows DLLs.
558 // #warning Is this correct? _imp is a pointer!
559 #define Char_hash_static_info _imp__ghczmprim_GHCziTypes_Czh_static_info
560 #define Int_hash_static_info _imp__ghczmprim_GHCziTypes_Izh_static_info
562 #define Char_hash_static_info ghczmprim_GHCziTypes_Czh_static_info
563 #define Int_hash_static_info ghczmprim_GHCziTypes_Izh_static_info
567 #define CHARLIKE_HDR(n) CLOSURE(Char_hash_static_info, n)
568 #define INTLIKE_HDR(n) CLOSURE(Int_hash_static_info, n)
570 /* put these in the *data* section, since the garbage collector relies
571 * on the fact that static closures live in the data section.
574 /* end the name with _closure, to convince the mangler this is a closure */
576 #if !(defined(__PIC__) && defined(mingw32_HOST_OS))
578 stg_CHARLIKE_closure:
839 INTLIKE_HDR(-16) /* MIN_INTLIKE == -16 */
871 INTLIKE_HDR(16) /* MAX_INTLIKE == 16 */
874 #endif // !(defined(__PIC__) && defined(mingw32_HOST_OS))