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 )
57 -> Module -- Module name
58 -> [Module] -- Import names
59 -> ([CostCentre], -- Local cost-centres needing declaring/registering
60 [CostCentre], -- "extern" cost-centres needing declaring
61 [CostCentreStack]) -- Pre-defined "singleton" cost centre stacks
62 -> [Id] -- foreign-exported binders
63 -> [TyCon] -- Local tycons, including ones from classes
64 -> [(StgBinding,[Id])] -- Bindings to convert, with SRTs
65 -> IO AbstractC -- Output
67 codeGen dflags mod_name imported_modules cost_centre_info fe_binders
69 = do { showPass dflags "CodeGen"
71 ; fl_uniqs <- mkSplitUniqSupply 'f'
73 datatype_stuff = genStaticConBits cinfo data_tycons
74 code_stuff = initC cinfo (mapCs cgTopBinding stg_binds)
75 init_stuff = mkModuleInit fe_binders mod_name imported_modules
78 abstractC = mkAbstractCs [ maybeSplitCode,
82 -- Put datatype_stuff after code_stuff, because the
83 -- datatype closure table (for enumeration types)
84 -- to (say) PrelBase_True_closure, which is defined in code_stuff
86 flat_abstractC = flattenAbsC fl_uniqs abstractC
88 ; dumpIfSet_dyn dflags Opt_D_dump_absC "Abstract C" (dumpRealC abstractC)
89 ; return flat_abstractC
92 data_tycons = filter isDataTyCon tycons
94 cinfo = MkCompInfo mod_name
97 %************************************************************************
99 \subsection[codegen-init]{Module initialisation code}
101 %************************************************************************
105 :: [Id] -- foreign exported functions
106 -> Module -- module name
107 -> [Module] -- import names
108 -> ([CostCentre], -- cost centre info
112 mkModuleInit fe_binders mod imps cost_centre_info
115 map (\f -> CMacroStmt REGISTER_FOREIGN_EXPORT [f]) fe_labels
118 map (\f -> CLbl (mkClosureLabel (idName f)) PtrRep) fe_binders
120 (cc_decls, cc_regs) = mkCostCentreStuff cost_centre_info
122 mk_import_register imp =
123 CMacroStmt REGISTER_IMPORT [
124 CLbl (mkModuleInitLabel imp) AddrRep
127 register_imports = map mk_import_register imps
131 CModuleInitBlock (mkModuleInitLabel mod)
132 (mkAbstractCs (register_fes ++
138 Cost-centre profiling: Besides the usual stuff, we must produce
139 declarations for the cost-centres defined in this module;
141 (The local cost-centres involved in this are passed into the
145 mkCostCentreStuff (local_CCs, extern_CCs, singleton_CCSs)
146 | not opt_SccProfilingOn = (AbsCNop, AbsCNop)
149 map (CCostCentreDecl True) local_CCs ++
150 map (CCostCentreDecl False) extern_CCs ++
151 map CCostCentreStackDecl singleton_CCSs),
152 mkAbstractCs (mkCcRegister local_CCs singleton_CCSs)
155 mkCcRegister ccs cc_stacks
157 register_ccs = mkAbstractCs (map mk_register ccs)
158 register_cc_stacks = mkAbstractCs (map mk_register_ccs cc_stacks)
160 [ register_ccs, register_cc_stacks ]
163 = CCallProfCCMacro SLIT("REGISTER_CC") [mkCCostCentre cc]
166 = CCallProfCCMacro SLIT("REGISTER_CCS") [mkCCostCentreStack ccs]
169 %************************************************************************
171 \subsection[codegen-top-bindings]{Converting top-level STG bindings}
173 %************************************************************************
175 @cgTopBinding@ is only used for top-level bindings, since they need
176 to be allocated statically (not in the heap) and need to be labelled.
177 No unboxed bindings can happen at top level.
179 In the code below, the static bindings are accumulated in the
180 @MkCgState@, and transferred into the ``statics'' slot by @forkStatics@.
181 This is so that we can write the top level processing in a compositional
182 style, with the increasing static environment being plumbed as a state
186 cgTopBinding :: (StgBinding,[Id]) -> Code
187 cgTopBinding (StgNonRec id rhs, srt)
188 = absC maybeSplitCode `thenC`
189 maybeGlobaliseId id `thenFC` \ id' ->
191 srt_label = mkSRTLabel (idName id')
193 mkSRT srt_label srt [] `thenC`
194 setSRTLabel srt_label (
195 cgTopRhs id' rhs `thenFC` \ (id, info) ->
199 cgTopBinding (StgRec pairs, srt)
200 = absC maybeSplitCode `thenC`
202 (bndrs, rhss) = unzip pairs
204 mapFCs maybeGlobaliseId bndrs `thenFC` \ bndrs'@(id:_) ->
206 srt_label = mkSRTLabel (idName id)
207 pairs' = zip bndrs' rhss
209 mkSRT srt_label srt bndrs' `thenC`
210 setSRTLabel srt_label (
212 addBindsC new_binds `thenC`
213 mapFCs ( \ (b,e) -> cgTopRhs b e ) pairs'
214 ) `thenFC` \ new_binds -> nopC
217 mkSRT :: CLabel -> [Id] -> [Id] -> Code
218 mkSRT lbl [] these = nopC
220 = mapFCs remap ids `thenFC` \ ids ->
221 absC (CSRT lbl (map (mkClosureLabel . idName) ids))
223 -- sigh, better map all the ids against the environment in case they've
224 -- been globalised (see maybeGlobaliseId below).
225 remap id = case filter (==id) these of
226 [] -> getCAddrModeAndInfo id
227 `thenFC` \ (id, _, _) -> returnFC id
228 (id':_) -> returnFC id'
230 -- if we're splitting the object, we need to globalise all the top-level names
231 -- (and then make sure we only use the globalised one in any C label we use
232 -- which refers to this name).
233 maybeGlobaliseId :: Id -> FCode Id
235 = moduleName `thenFC` \ mod ->
239 -- globalise the name for -split-objs, if necessary
240 real_name | opt_EnsureSplittableC = globaliseName name mod
243 id' = setIdName id real_name
248 | opt_EnsureSplittableC = CSplitMarker
249 | otherwise = AbsCNop
251 -- Urgh! I tried moving the forkStatics call from the rhss of cgTopRhs
252 -- to enclose the listFCs in cgTopBinding, but that tickled the
253 -- statics "error" call in initC. I DON'T UNDERSTAND WHY!
255 cgTopRhs :: Id -> StgRhs -> FCode (Id, CgIdInfo)
256 -- the Id is passed along for setting up a binding...
258 cgTopRhs bndr (StgRhsCon cc con args)
259 = maybeGlobaliseId bndr `thenFC` \ bndr' ->
260 forkStatics (cgTopRhsCon bndr con args)
262 cgTopRhs bndr (StgRhsClosure cc bi srt fvs upd_flag args body)
263 = ASSERT(null fvs) -- There should be no free variables
264 getSRTLabel `thenFC` \srt_label ->
266 mkClosureLFInfo bndr TopLevel [{-no fvs-}] upd_flag args srt_label srt
268 maybeGlobaliseId bndr `thenFC` \ bndr' ->
269 forkStatics (cgTopRhsClosure bndr' cc bi args body lf_info)