2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
4 \section[CodeGen]{@CodeGen@: main module of the code generator}
6 This module says how things get going at the top level.
8 @codeGen@ is the interface to the outside world. The \tr{cgTop*}
9 functions drive the mangling of top-level bindings.
11 %************************************************************************
13 \subsection[codeGen-outside-interface]{The code generator's offering to the world}
15 %************************************************************************
18 module CodeGen ( codeGen ) where
20 #include "HsVersions.h"
22 -- Kludge (??) so that CgExpr is reached via at least one non-SOURCE
23 -- import. Before, that wasn't the case, and CM therefore didn't
24 -- bother to compile it.
25 import CgExpr ( {-NOTHING!-} ) -- DO NOT DELETE THIS IMPORT
30 import CLabel ( CLabel, mkSRTLabel, mkClosureLabel, mkModuleInitLabel )
32 import PprAbsC ( dumpRealC )
33 import AbsCUtils ( mkAbstractCs, flattenAbsC )
34 import CgBindery ( CgIdInfo, addBindC, addBindsC, getCAddrModeAndInfo )
35 import CgClosure ( cgTopRhsClosure )
36 import CgCon ( cgTopRhsCon )
37 import CgConTbls ( genStaticConBits )
38 import ClosureInfo ( mkClosureLFInfo )
39 import CmdLineOpts ( DynFlags, DynFlag(..),
40 opt_SccProfilingOn, opt_EnsureSplittableC )
41 import CostCentre ( CostCentre, CostCentreStack )
42 import Id ( Id, idName, setIdName )
43 import Name ( globaliseName )
44 import Module ( Module )
45 import PrimRep ( PrimRep(..) )
46 import TyCon ( TyCon, isDataTyCon )
47 import BasicTypes ( TopLevelFlag(..) )
48 import UniqSupply ( mkSplitUniqSupply )
49 import ErrUtils ( dumpIfSet_dyn, showPass )
50 import Panic ( assertPanic )
53 import Id ( idCafInfo )
54 import IdInfo ( mayHaveCafRefs )
61 -> Module -- Module name
62 -> [Module] -- Import names
63 -> ([CostCentre], -- Local cost-centres needing declaring/registering
64 [CostCentre], -- "extern" cost-centres needing declaring
65 [CostCentreStack]) -- Pre-defined "singleton" cost centre stacks
66 -> [Id] -- foreign-exported binders
67 -> [TyCon] -- Local tycons, including ones from classes
68 -> [(StgBinding,[Id])] -- Bindings to convert, with SRTs
69 -> IO AbstractC -- Output
71 codeGen dflags mod_name imported_modules cost_centre_info fe_binders
73 = do { showPass dflags "CodeGen"
75 ; fl_uniqs <- mkSplitUniqSupply 'f'
77 datatype_stuff = genStaticConBits cinfo data_tycons
78 code_stuff = initC cinfo (mapCs cgTopBinding stg_binds)
79 init_stuff = mkModuleInit fe_binders mod_name imported_modules
82 abstractC = mkAbstractCs [ maybeSplitCode,
86 -- Put datatype_stuff after code_stuff, because the
87 -- datatype closure table (for enumeration types)
88 -- to (say) PrelBase_True_closure, which is defined in code_stuff
90 flat_abstractC = flattenAbsC fl_uniqs abstractC
92 ; dumpIfSet_dyn dflags Opt_D_dump_absC "Abstract C" (dumpRealC abstractC)
93 ; return flat_abstractC
96 data_tycons = filter isDataTyCon tycons
98 cinfo = MkCompInfo mod_name
101 %************************************************************************
103 \subsection[codegen-init]{Module initialisation code}
105 %************************************************************************
109 :: [Id] -- foreign exported functions
110 -> Module -- module name
111 -> [Module] -- import names
112 -> ([CostCentre], -- cost centre info
116 mkModuleInit fe_binders mod imps cost_centre_info
119 map (\f -> CMacroStmt REGISTER_FOREIGN_EXPORT [f]) fe_labels
122 map (\f -> CLbl (mkClosureLabel (idName f)) PtrRep) fe_binders
124 (cc_decls, cc_regs) = mkCostCentreStuff cost_centre_info
126 mk_import_register imp =
127 CMacroStmt REGISTER_IMPORT [
128 CLbl (mkModuleInitLabel imp) AddrRep
131 register_imports = map mk_import_register imps
135 CModuleInitBlock (mkModuleInitLabel mod)
136 (mkAbstractCs (register_fes ++
142 Cost-centre profiling: Besides the usual stuff, we must produce
143 declarations for the cost-centres defined in this module;
145 (The local cost-centres involved in this are passed into the
149 mkCostCentreStuff (local_CCs, extern_CCs, singleton_CCSs)
150 | not opt_SccProfilingOn = (AbsCNop, AbsCNop)
153 map (CCostCentreDecl True) local_CCs ++
154 map (CCostCentreDecl False) extern_CCs ++
155 map CCostCentreStackDecl singleton_CCSs),
156 mkAbstractCs (mkCcRegister local_CCs singleton_CCSs)
159 mkCcRegister ccs cc_stacks
161 register_ccs = mkAbstractCs (map mk_register ccs)
162 register_cc_stacks = mkAbstractCs (map mk_register_ccs cc_stacks)
164 [ register_ccs, register_cc_stacks ]
167 = CCallProfCCMacro SLIT("REGISTER_CC") [mkCCostCentre cc]
170 = CCallProfCCMacro SLIT("REGISTER_CCS") [mkCCostCentreStack ccs]
173 %************************************************************************
175 \subsection[codegen-top-bindings]{Converting top-level STG bindings}
177 %************************************************************************
179 @cgTopBinding@ is only used for top-level bindings, since they need
180 to be allocated statically (not in the heap) and need to be labelled.
181 No unboxed bindings can happen at top level.
183 In the code below, the static bindings are accumulated in the
184 @MkCgState@, and transferred into the ``statics'' slot by @forkStatics@.
185 This is so that we can write the top level processing in a compositional
186 style, with the increasing static environment being plumbed as a state
190 cgTopBinding :: (StgBinding,[Id]) -> Code
191 cgTopBinding (StgNonRec srt_info id rhs, srt)
192 = absC maybeSplitCode `thenC`
193 maybeGlobaliseId id `thenFC` \ id' ->
195 srt_label = mkSRTLabel (idName id')
197 mkSRT srt_label srt [] `thenC`
198 setSRTLabel srt_label (
199 cgTopRhs id' rhs srt_info `thenFC` \ (id, info) ->
203 cgTopBinding (StgRec srt_info pairs, srt)
204 = absC maybeSplitCode `thenC`
206 (bndrs, rhss) = unzip pairs
208 mapFCs maybeGlobaliseId bndrs `thenFC` \ bndrs'@(id:_) ->
210 srt_label = mkSRTLabel (idName id)
211 pairs' = zip bndrs' rhss
213 mkSRT srt_label srt bndrs' `thenC`
214 setSRTLabel srt_label (
216 addBindsC new_binds `thenC`
217 mapFCs ( \ (b,e) -> cgTopRhs b e srt_info ) pairs'
218 ) `thenFC` \ new_binds -> nopC
221 mkSRT :: CLabel -> [Id] -> [Id] -> Code
222 mkSRT lbl [] these = nopC
224 = mapFCs remap ids `thenFC` \ ids ->
225 absC (CSRT lbl (map (mkClosureLabel . idName) ids))
227 -- sigh, better map all the ids against the environment in case they've
228 -- been globalised (see maybeGlobaliseId below).
229 remap id = case filter (==id) these of
230 [] -> getCAddrModeAndInfo id
231 `thenFC` \ (id, _, _) -> returnFC id
232 (id':_) -> returnFC id'
234 -- if we're splitting the object, we need to globalise all the top-level names
235 -- (and then make sure we only use the globalised one in any C label we use
236 -- which refers to this name).
237 maybeGlobaliseId :: Id -> FCode Id
239 = moduleName `thenFC` \ mod ->
243 -- globalise the name for -split-objs, if necessary
244 real_name | opt_EnsureSplittableC = globaliseName name mod
247 id' = setIdName id real_name
252 | opt_EnsureSplittableC = CSplitMarker
253 | otherwise = AbsCNop
255 -- Urgh! I tried moving the forkStatics call from the rhss of cgTopRhs
256 -- to enclose the listFCs in cgTopBinding, but that tickled the
257 -- statics "error" call in initC. I DON'T UNDERSTAND WHY!
259 cgTopRhs :: Id -> StgRhs -> SRT -> FCode (Id, CgIdInfo)
260 -- the Id is passed along for setting up a binding...
262 cgTopRhs bndr (StgRhsCon cc con args) srt
263 = maybeGlobaliseId bndr `thenFC` \ bndr' ->
264 forkStatics (cgTopRhsCon bndr con args)
266 cgTopRhs bndr (StgRhsClosure cc bi fvs upd_flag args body) srt
267 = -- There should be no free variables
270 getSRTLabel `thenFC` \srt_label ->
272 mkClosureLFInfo bndr TopLevel [{-no fvs-}] upd_flag args srt_label srt
274 maybeGlobaliseId bndr `thenFC` \ bndr' ->
275 forkStatics (cgTopRhsClosure bndr' cc bi args body lf_info)