2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
4 % $Id: CLabel.lhs,v 1.46 2001/04/20 14:54:37 sewardj Exp $
6 \section[CLabel]{@CLabel@: Information to make C Labels}
10 CLabel, -- abstract type
18 mkStaticConEntryLabel,
21 mkStaticInfoTableLabel,
48 mkCharlikeClosureLabel,
49 mkIntlikeClosureLabel,
50 mkMAP_FROZEN_infoLabel,
51 mkEMPTY_MVAR_infoLabel,
54 mkBlackHoleInfoTableLabel,
55 mkCAFBlackHoleInfoTableLabel,
56 mkSECAFBlackHoleInfoTableLabel,
66 mkCC_Label, mkCCS_Label,
68 needsCDecl, isAsmTemp, externallyVisibleCLabel,
70 CLabelType(..), labelType, labelDynamic,
73 #if ! OMIT_NATIVE_CODEGEN
79 #include "HsVersions.h"
81 #if ! OMIT_NATIVE_CODEGEN
82 import {-# SOURCE #-} MachMisc ( underscorePrefix, fmtAsmLbl )
85 import CmdLineOpts ( opt_Static, opt_DoTickyProfiling )
86 import CStrings ( pp_cSEP )
87 import DataCon ( ConTag )
88 import Module ( moduleName, moduleNameFS,
89 Module, isHomeModule )
90 import Name ( Name, getName, isDllName, isExternallyVisibleName )
91 import TyCon ( TyCon )
92 import Unique ( pprUnique, Unique )
93 import PrimOp ( PrimOp )
94 import CostCentre ( CostCentre, CostCentreStack )
98 things we want to find out:
100 * should the labelled things be declared "static" (visible only in this file)?
102 * should it be declared "const" (read-only text space)?
104 * does it need declarations at all? (v common Prelude things are pre-declared)
106 * what type does it have? (for generating accurate enough C declarations
107 so that the C compiler won't complain).
111 = IdLabel -- A family of labels related to the
112 Name -- definition of a particular Id
115 | DataConLabel -- Ditto data constructors
119 | CaseLabel -- A family of labels related to a particular case expression
120 Unique -- Unique says which case expression
123 | TyConLabel TyCon -- currently only one kind of TyconLabel,
124 -- a 'Closure Table'.
126 | AsmTempLabel Unique
128 | ModuleInitLabel Module
130 | RtsLabel RtsLabelInfo
132 | ForeignLabel FAST_STRING Bool -- a 'C' (or otherwise foreign) label
133 -- Bool <=> is dynamic
135 | CC_Label CostCentre
136 | CCS_Label CostCentreStack
143 = Closure -- Label for (static???) closure
145 | SRT -- Static reference table
147 | InfoTbl -- Info table for a closure; always read-only
149 | EntryStd -- Thunk, or "slow", code entry point
151 | EntryFast Int -- entry pt when no arg satisfaction chk needed;
152 -- Int is the arity of the function (to be
153 -- encoded into the name)
155 -- Ticky-ticky counting
156 | RednCounts -- Label of place to keep reduction-count info for
160 data DataConLabelInfo
161 = ConEntry -- the only kind of entry pt for constructors
162 | ConInfoTbl -- corresponding info table
163 | StaticConEntry -- static constructor entry point
164 | StaticInfoTbl -- corresponding info table
177 = RtsShouldNeverHappenCode
179 | RtsBlackHoleInfoTbl FAST_STRING -- black hole with info table name
181 | RtsUpdInfo -- upd_frame_info
182 | RtsSeqInfo -- seq_frame_info
183 | RtsGCEntryLabel String -- a heap check fail handler, eg stg_chk_2
184 | RtsMainRegTable -- MainRegTable (??? Capabilities wurble ???)
185 | Rts_Closure String -- misc rts closures, eg CHARLIKE_closure
186 | Rts_Info String -- misc rts itbls, eg MUT_ARR_PTRS_FROZEN_info
187 | Rts_Code String -- misc rts code
189 | RtsSelectorInfoTbl Bool{-updatable-} Int{-offset-} -- Selector thunks
190 | RtsSelectorEntry Bool{-updatable-} Int{-offset-}
192 | RtsApInfoTbl Bool{-updatable-} Int{-arity-} -- AP thunks
193 | RtsApEntry Bool{-updatable-} Int{-arity-}
203 -- Label Type: for generating C declarations.
215 mkClosureLabel id = IdLabel id Closure
216 mkSRTLabel id = IdLabel id SRT
217 mkInfoTableLabel id = IdLabel id InfoTbl
218 mkStdEntryLabel id = IdLabel id EntryStd
219 mkFastEntryLabel id arity = ASSERT(arity > 0)
220 IdLabel id (EntryFast arity)
222 mkRednCountsLabel id = IdLabel id RednCounts
224 mkStaticInfoTableLabel con = DataConLabel con StaticInfoTbl
225 mkConInfoTableLabel con = DataConLabel con ConInfoTbl
226 mkConEntryLabel con = DataConLabel con ConEntry
227 mkStaticConEntryLabel con = DataConLabel con StaticConEntry
230 mkReturnPtLabel uniq = CaseLabel uniq CaseReturnPt
231 mkReturnInfoLabel uniq = CaseLabel uniq CaseReturnInfo
232 mkVecTblLabel uniq = CaseLabel uniq CaseVecTbl
233 mkAltLabel uniq tag = CaseLabel uniq (CaseAlt tag)
234 mkDefaultLabel uniq = CaseLabel uniq CaseDefault
235 mkBitmapLabel uniq = CaseLabel uniq CaseBitmap
237 mkClosureTblLabel tycon = TyConLabel tycon
239 mkAsmTempLabel = AsmTempLabel
241 mkModuleInitLabel = ModuleInitLabel
243 -- Some fixed runtime system labels
245 mkErrorStdEntryLabel = RtsLabel RtsShouldNeverHappenCode
246 mkStgUpdatePAPLabel = RtsLabel (Rts_Code "stg_update_PAP")
247 mkSplitMarkerLabel = RtsLabel (Rts_Code "__stg_split_marker")
248 mkUpdInfoLabel = RtsLabel RtsUpdInfo
249 mkSeqInfoLabel = RtsLabel RtsSeqInfo
250 mkIndInfoLabel = RtsLabel (Rts_Info "stg_IND_info")
251 mkIndStaticInfoLabel = RtsLabel (Rts_Info "stg_IND_STATIC_info")
252 mkRtsGCEntryLabel str = RtsLabel (RtsGCEntryLabel str)
253 mkMainRegTableLabel = RtsLabel RtsMainRegTable
254 mkCharlikeClosureLabel = RtsLabel (Rts_Closure "stg_CHARLIKE_closure")
255 mkIntlikeClosureLabel = RtsLabel (Rts_Closure "stg_INTLIKE_closure")
256 mkMAP_FROZEN_infoLabel = RtsLabel (Rts_Info "stg_MUT_ARR_PTRS_FROZEN_info")
257 mkEMPTY_MVAR_infoLabel = RtsLabel (Rts_Info "stg_EMPTY_MVAR_info")
259 mkTopTickyCtrLabel = RtsLabel RtsTopTickyCtr
260 mkBlackHoleInfoTableLabel = RtsLabel (RtsBlackHoleInfoTbl SLIT("stg_BLACKHOLE_info"))
261 mkCAFBlackHoleInfoTableLabel = RtsLabel (RtsBlackHoleInfoTbl SLIT("stg_CAF_BLACKHOLE_info"))
262 mkSECAFBlackHoleInfoTableLabel = if opt_DoTickyProfiling then
263 RtsLabel (RtsBlackHoleInfoTbl SLIT("stg_SE_CAF_BLACKHOLE_info"))
264 else -- RTS won't have info table unless -ticky is on
265 panic "mkSECAFBlackHoleInfoTableLabel requires -ticky"
266 mkRtsPrimOpLabel primop = RtsLabel (RtsPrimOp primop)
268 moduleRegdLabel = RtsLabel RtsModuleRegd
270 mkSelectorInfoLabel upd off = RtsLabel (RtsSelectorInfoTbl upd off)
271 mkSelectorEntryLabel upd off = RtsLabel (RtsSelectorEntry upd off)
273 mkApInfoTableLabel upd off = RtsLabel (RtsApInfoTbl upd off)
274 mkApEntryLabel upd off = RtsLabel (RtsApEntry upd off)
278 mkForeignLabel :: FAST_STRING -> Bool -> CLabel
279 mkForeignLabel str is_dynamic = ForeignLabel str is_dynamic
283 mkCC_Label cc = CC_Label cc
284 mkCCS_Label ccs = CCS_Label ccs
288 needsCDecl :: CLabel -> Bool -- False <=> it's pre-declared; don't bother
289 isAsmTemp :: CLabel -> Bool -- is a local temporary for native code generation
290 externallyVisibleCLabel :: CLabel -> Bool -- not C "static"
293 @needsCDecl@ is @True@ unless the thing is a deeply-@PreludeCore@-ish
294 object. {\em Also:} No need to spit out labels for things generated
295 by the flattener (in @AbsCUtils@)---it is careful to ensure references
296 to them are always backwards. These are return-point and vector-table
299 Declarations for (non-prelude) @Id@-based things are needed because of
302 Declarations for direct return points are needed, because they may be
303 let-no-escapes, which can be recursive.
306 needsCDecl (IdLabel _ _) = True
307 needsCDecl (CaseLabel _ CaseReturnPt) = True
308 needsCDecl (DataConLabel _ _) = True
309 needsCDecl (TyConLabel _) = True
310 needsCDecl (ModuleInitLabel _) = True
312 needsCDecl (CaseLabel _ _) = False
313 needsCDecl (AsmTempLabel _) = False
314 needsCDecl (RtsLabel _) = False
315 needsCDecl (ForeignLabel _ _) = False
316 needsCDecl (CC_Label _) = False
317 needsCDecl (CCS_Label _) = False
320 Whether the label is an assembler temporary:
323 isAsmTemp (AsmTempLabel _) = True
327 C ``static'' or not...
328 From the point of view of the code generator, a name is
329 externally visible if it has to be declared as exported
330 in the .o file's symbol table; that is, made non-static.
333 externallyVisibleCLabel (DataConLabel _ _) = True
334 externallyVisibleCLabel (TyConLabel tc) = True
335 externallyVisibleCLabel (CaseLabel _ _) = False
336 externallyVisibleCLabel (AsmTempLabel _) = False
337 externallyVisibleCLabel (ModuleInitLabel _)= True
338 externallyVisibleCLabel (RtsLabel RtsModuleRegd) = False --hack
339 externallyVisibleCLabel (RtsLabel _) = True
340 externallyVisibleCLabel (ForeignLabel _ _) = True
341 externallyVisibleCLabel (IdLabel id _) = isExternallyVisibleName id
342 externallyVisibleCLabel (CC_Label _) = False -- not strictly true
343 externallyVisibleCLabel (CCS_Label _) = False -- not strictly true
346 For generating correct types in label declarations...
349 labelType :: CLabel -> CLabelType
350 labelType (RtsLabel (RtsBlackHoleInfoTbl _)) = InfoTblType
351 labelType (RtsLabel (RtsSelectorInfoTbl _ _)) = InfoTblType
352 labelType (RtsLabel (RtsApInfoTbl _ _)) = InfoTblType
353 labelType (RtsLabel RtsUpdInfo) = InfoTblType
354 labelType (CaseLabel _ CaseReturnInfo) = InfoTblType
355 labelType (CaseLabel _ CaseReturnPt) = CodeType
356 labelType (CaseLabel _ CaseVecTbl) = VecTblType
357 labelType (TyConLabel _) = ClosureTblType
358 labelType (ModuleInitLabel _ ) = CodeType
360 labelType (IdLabel _ info) =
362 InfoTbl -> InfoTblType
363 Closure -> ClosureType
366 labelType (DataConLabel _ info) =
368 ConInfoTbl -> InfoTblType
369 StaticInfoTbl -> InfoTblType
372 labelType _ = DataType
375 When referring to data in code, we need to know whether
376 that data resides in a DLL or not. [Win32 only.]
377 @labelDynamic@ returns @True@ if the label is located
378 in a DLL, be it a data reference or not.
381 labelDynamic :: CLabel -> Bool
384 -- The special case for RtsShouldNeverHappenCode is because the associated address is
385 -- NULL, i.e. not a DLL entry point
386 RtsLabel RtsShouldNeverHappenCode -> False
387 RtsLabel _ -> not opt_Static -- i.e., is the RTS in a DLL or not?
388 IdLabel n k -> isDllName n
389 DataConLabel n k -> isDllName n
390 TyConLabel tc -> isDllName (getName tc)
391 ForeignLabel _ d -> d
392 ModuleInitLabel m -> (not opt_Static) && (not (isHomeModule m))
397 OLD?: These GRAN functions are needed for spitting out GRAN_FETCH() at the
398 right places. It is used to detect when the abstractC statement of an
399 CCodeBlock actually contains the code for a slow entry point. -- HWL
401 We need at least @Eq@ for @CLabels@, because we want to avoid
402 duplicate declarations in generating C (see @labelSeenTE@ in
405 -----------------------------------------------------------------------------
406 Printing out CLabels.
412 where <name> is <Module>_<name> for external names and <unique> for
413 internal names. <type> is one of the following:
416 srt Static reference table
418 ret Direct return address
420 <n>_alt Case alternative (tag n)
421 dflt Default case alternative
422 btm Large bitmap vector
423 closure Static closure
424 con_entry Dynamic Constructor entry code
425 con_info Dynamic Constructor info table
426 static_entry Static Constructor entry code
427 static_info Static Constructor info table
428 sel_info Selector info table
429 sel_entry Selector entry code
431 ccs Cost centre stack
434 -- specialised for PprAsm: saves lots of arg passing in NCG
435 #if ! OMIT_NATIVE_CODEGEN
436 pprCLabel_asm = pprCLabel
439 pprCLabel :: CLabel -> SDoc
441 #if ! OMIT_NATIVE_CODEGEN
442 pprCLabel (AsmTempLabel u)
443 = text (fmtAsmLbl (show u))
447 #if ! OMIT_NATIVE_CODEGEN
448 getPprStyle $ \ sty ->
449 if asmStyle sty && underscorePrefix then
450 pp_cSEP <> pprCLbl lbl
455 pprCLbl (CaseLabel u CaseReturnPt)
456 = hcat [pprUnique u, pp_cSEP, ptext SLIT("ret")]
457 pprCLbl (CaseLabel u CaseReturnInfo)
458 = hcat [pprUnique u, pp_cSEP, ptext SLIT("info")]
459 pprCLbl (CaseLabel u CaseVecTbl)
460 = hcat [pprUnique u, pp_cSEP, ptext SLIT("vtbl")]
461 pprCLbl (CaseLabel u (CaseAlt tag))
462 = hcat [pprUnique u, pp_cSEP, int tag, pp_cSEP, ptext SLIT("alt")]
463 pprCLbl (CaseLabel u CaseDefault)
464 = hcat [pprUnique u, pp_cSEP, ptext SLIT("dflt")]
465 pprCLbl (CaseLabel u CaseBitmap)
466 = hcat [pprUnique u, pp_cSEP, ptext SLIT("btm")]
468 pprCLbl (RtsLabel RtsShouldNeverHappenCode) = ptext SLIT("NULL")
469 -- used to be stg_error_entry but Windows can't have DLL entry points as static
470 -- initialisers, and besides, this ShouldNeverHappen, right?
472 pprCLbl (RtsLabel RtsUpdInfo) = ptext SLIT("stg_upd_frame_info")
473 pprCLbl (RtsLabel RtsSeqInfo) = ptext SLIT("stg_seq_frame_info")
474 pprCLbl (RtsLabel RtsMainRegTable) = ptext SLIT("MainRegTable")
475 pprCLbl (RtsLabel (RtsGCEntryLabel str)) = text str
476 pprCLbl (RtsLabel (Rts_Closure str)) = text str
477 pprCLbl (RtsLabel (Rts_Info str)) = text str
478 pprCLbl (RtsLabel (Rts_Code str)) = text str
480 pprCLbl (RtsLabel RtsTopTickyCtr) = ptext SLIT("top_ct")
482 pprCLbl (RtsLabel (RtsBlackHoleInfoTbl info)) = ptext info
484 pprCLbl (RtsLabel (RtsSelectorInfoTbl upd_reqd offset))
485 = hcat [ptext SLIT("stg_sel_"), text (show offset),
487 then SLIT("_upd_info")
488 else SLIT("_noupd_info"))
491 pprCLbl (RtsLabel (RtsSelectorEntry upd_reqd offset))
492 = hcat [ptext SLIT("stg_sel_"), text (show offset),
494 then SLIT("_upd_entry")
495 else SLIT("_noupd_entry"))
498 pprCLbl (RtsLabel (RtsApInfoTbl upd_reqd arity))
499 = hcat [ptext SLIT("stg_ap_"), text (show arity),
501 then SLIT("_upd_info")
502 else SLIT("_noupd_info"))
505 pprCLbl (RtsLabel (RtsApEntry upd_reqd arity))
506 = hcat [ptext SLIT("stg_ap_"), text (show arity),
508 then SLIT("_upd_entry")
509 else SLIT("_noupd_entry"))
512 pprCLbl (RtsLabel (RtsPrimOp primop))
513 = ppr primop <> ptext SLIT("_fast")
515 pprCLbl (RtsLabel RtsModuleRegd)
516 = ptext SLIT("module_registered")
518 pprCLbl (ForeignLabel str _)
521 pprCLbl (TyConLabel tc)
522 = hcat [ppr tc, pp_cSEP, ptext SLIT("closure_tbl")]
524 pprCLbl (IdLabel id flavor) = ppr id <> ppIdFlavor flavor
525 pprCLbl (DataConLabel con flavor) = ppr con <> ppConFlavor flavor
527 pprCLbl (CC_Label cc) = ppr cc
528 pprCLbl (CCS_Label ccs) = ppr ccs
530 pprCLbl (ModuleInitLabel mod)
531 = ptext SLIT("__init_") <> ptext (moduleNameFS (moduleName mod))
533 ppIdFlavor :: IdLabelInfo -> SDoc
535 ppIdFlavor x = pp_cSEP <>
537 Closure -> ptext SLIT("closure")
538 SRT -> ptext SLIT("srt")
539 InfoTbl -> ptext SLIT("info")
540 EntryStd -> ptext SLIT("entry")
541 EntryFast arity -> --false:ASSERT (arity > 0)
542 (<>) (ptext SLIT("fast")) (int arity)
543 RednCounts -> ptext SLIT("ct")
546 ppConFlavor x = pp_cSEP <>
548 ConEntry -> ptext SLIT("con_entry")
549 ConInfoTbl -> ptext SLIT("con_info")
550 StaticConEntry -> ptext SLIT("static_entry")
551 StaticInfoTbl -> ptext SLIT("static_info")