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 )
59 -> Module -- Module name
60 -> [Module] -- Import names
61 -> ([CostCentre], -- Local cost-centres needing declaring/registering
62 [CostCentre], -- "extern" cost-centres needing declaring
63 [CostCentreStack]) -- Pre-defined "singleton" cost centre stacks
64 -> [Id] -- foreign-exported binders
65 -> [TyCon] -- Local tycons, including ones from classes
66 -> [(StgBinding,[Id])] -- Bindings to convert, with SRTs
67 -> IO AbstractC -- Output
69 codeGen dflags mod_name imported_modules cost_centre_info fe_binders
71 = do { showPass dflags "CodeGen"
73 ; fl_uniqs <- mkSplitUniqSupply 'f'
75 datatype_stuff = genStaticConBits cinfo data_tycons
76 code_stuff = initC cinfo (mapCs cgTopBinding stg_binds)
77 init_stuff = mkModuleInit fe_binders mod_name imported_modules
80 abstractC = mkAbstractCs [ maybeSplitCode,
84 -- Put datatype_stuff after code_stuff, because the
85 -- datatype closure table (for enumeration types)
86 -- to (say) PrelBase_True_closure, which is defined in code_stuff
88 flat_abstractC = flattenAbsC fl_uniqs abstractC
90 ; dumpIfSet_dyn dflags Opt_D_dump_absC "Abstract C" (dumpRealC abstractC)
91 ; return flat_abstractC
94 data_tycons = filter isDataTyCon tycons
96 cinfo = MkCompInfo mod_name
99 %************************************************************************
101 \subsection[codegen-init]{Module initialisation code}
103 %************************************************************************
107 :: [Id] -- foreign exported functions
108 -> Module -- module name
109 -> [Module] -- import names
110 -> ([CostCentre], -- cost centre info
114 mkModuleInit fe_binders mod imps cost_centre_info
117 map (\f -> CMacroStmt REGISTER_FOREIGN_EXPORT [f]) fe_labels
120 map (\f -> CLbl (mkClosureLabel (idName f)) PtrRep) fe_binders
122 (cc_decls, cc_regs) = mkCostCentreStuff cost_centre_info
124 mk_import_register imp =
125 CMacroStmt REGISTER_IMPORT [
126 CLbl (mkModuleInitLabel imp) AddrRep
129 register_imports = map mk_import_register imps
133 CModuleInitBlock (mkModuleInitLabel mod)
134 (mkAbstractCs (register_fes ++
140 Cost-centre profiling: Besides the usual stuff, we must produce
141 declarations for the cost-centres defined in this module;
143 (The local cost-centres involved in this are passed into the
147 mkCostCentreStuff (local_CCs, extern_CCs, singleton_CCSs)
148 | not opt_SccProfilingOn = (AbsCNop, AbsCNop)
151 map (CCostCentreDecl True) local_CCs ++
152 map (CCostCentreDecl False) extern_CCs ++
153 map CCostCentreStackDecl singleton_CCSs),
154 mkAbstractCs (mkCcRegister local_CCs singleton_CCSs)
157 mkCcRegister ccs cc_stacks
159 register_ccs = mkAbstractCs (map mk_register ccs)
160 register_cc_stacks = mkAbstractCs (map mk_register_ccs cc_stacks)
162 [ register_ccs, register_cc_stacks ]
165 = CCallProfCCMacro SLIT("REGISTER_CC") [mkCCostCentre cc]
168 = CCallProfCCMacro SLIT("REGISTER_CCS") [mkCCostCentreStack ccs]
171 %************************************************************************
173 \subsection[codegen-top-bindings]{Converting top-level STG bindings}
175 %************************************************************************
177 @cgTopBinding@ is only used for top-level bindings, since they need
178 to be allocated statically (not in the heap) and need to be labelled.
179 No unboxed bindings can happen at top level.
181 In the code below, the static bindings are accumulated in the
182 @MkCgState@, and transferred into the ``statics'' slot by @forkStatics@.
183 This is so that we can write the top level processing in a compositional
184 style, with the increasing static environment being plumbed as a state
188 cgTopBinding :: (StgBinding,[Id]) -> Code
189 cgTopBinding (StgNonRec srt_info id rhs, srt)
190 = absC maybeSplitCode `thenC`
191 maybeGlobaliseId id `thenFC` \ id' ->
193 srt_label = mkSRTLabel (idName id')
195 mkSRT srt_label srt [] `thenC`
196 setSRTLabel srt_label (
197 cgTopRhs id' rhs srt_info `thenFC` \ (id, info) ->
201 cgTopBinding (StgRec srt_info pairs, srt)
202 = absC maybeSplitCode `thenC`
204 (bndrs, rhss) = unzip pairs
206 mapFCs maybeGlobaliseId bndrs `thenFC` \ bndrs'@(id:_) ->
208 srt_label = mkSRTLabel (idName id)
209 pairs' = zip bndrs' rhss
211 mkSRT srt_label srt bndrs' `thenC`
212 setSRTLabel srt_label (
214 addBindsC new_binds `thenC`
215 mapFCs ( \ (b,e) -> cgTopRhs b e srt_info ) pairs'
216 ) `thenFC` \ new_binds -> nopC
219 mkSRT :: CLabel -> [Id] -> [Id] -> Code
220 mkSRT lbl [] these = nopC
222 = mapFCs remap ids `thenFC` \ ids ->
223 absC (CSRT lbl (map (mkClosureLabel . idName) ids))
225 -- sigh, better map all the ids against the environment in case they've
226 -- been globalised (see maybeGlobaliseId below).
227 remap id = case filter (==id) these of
228 [] -> getCAddrModeAndInfo id
229 `thenFC` \ (id, _, _) -> returnFC id
230 (id':_) -> returnFC id'
232 -- if we're splitting the object, we need to globalise all the top-level names
233 -- (and then make sure we only use the globalised one in any C label we use
234 -- which refers to this name).
235 maybeGlobaliseId :: Id -> FCode Id
237 = moduleName `thenFC` \ mod ->
241 -- globalise the name for -split-objs, if necessary
242 real_name | opt_EnsureSplittableC = globaliseName name mod
245 id' = setIdName id real_name
250 | opt_EnsureSplittableC = CSplitMarker
251 | otherwise = AbsCNop
253 -- Urgh! I tried moving the forkStatics call from the rhss of cgTopRhs
254 -- to enclose the listFCs in cgTopBinding, but that tickled the
255 -- statics "error" call in initC. I DON'T UNDERSTAND WHY!
257 cgTopRhs :: Id -> StgRhs -> SRT -> FCode (Id, CgIdInfo)
258 -- the Id is passed along for setting up a binding...
260 cgTopRhs bndr (StgRhsCon cc con args) srt
261 = maybeGlobaliseId bndr `thenFC` \ bndr' ->
262 forkStatics (cgTopRhsCon bndr con args)
264 cgTopRhs bndr (StgRhsClosure cc bi fvs upd_flag args body) srt
265 = -- There should be no free variables
268 lf_info = mkClosureLFInfo bndr TopLevel [{-no fvs-}] upd_flag args
270 maybeGlobaliseId bndr `thenFC` \ bndr' ->
271 forkStatics (cgTopRhsClosure bndr' cc bi srt args body lf_info)