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"
25 import CLabel ( CLabel, mkSRTLabel, mkClosureLabel, mkModuleInitLabel )
27 import PprAbsC ( dumpRealC )
28 import AbsCUtils ( mkAbstractCs, flattenAbsC )
29 import CgBindery ( CgIdInfo, addBindC, addBindsC )
30 import CgClosure ( cgTopRhsClosure )
31 import CgCon ( cgTopRhsCon )
32 import CgConTbls ( genStaticConBits )
33 import ClosureInfo ( mkClosureLFInfo )
34 import CmdLineOpts ( DynFlags, DynFlag(..),
35 opt_SccProfilingOn, opt_EnsureSplittableC )
36 import CostCentre ( CostCentre, CostCentreStack )
37 import Id ( Id, idName )
38 import Module ( Module )
39 import PrimRep ( PrimRep(..) )
40 import TyCon ( TyCon, isDataTyCon )
41 import BasicTypes ( TopLevelFlag(..) )
42 import UniqSupply ( mkSplitUniqSupply )
43 import ErrUtils ( dumpIfSet_dyn )
44 import Panic ( assertPanic )
51 -> Module -- Module name
52 -> [Module] -- Import names
53 -> ([CostCentre], -- Local cost-centres needing declaring/registering
54 [CostCentre], -- "extern" cost-centres needing declaring
55 [CostCentreStack]) -- Pre-defined "singleton" cost centre stacks
56 -> [Id] -- foreign-exported binders
57 -> [TyCon] -- Local tycons, including ones from classes
58 -> [(StgBinding,[Id])] -- Bindings to convert, with SRTs
59 -> IO AbstractC -- Output
61 codeGen dflags mod_name imported_modules cost_centre_info fe_binders
63 = mkSplitUniqSupply 'f' >>= \ fl_uniqs -> -- absC flattener
65 datatype_stuff = genStaticConBits cinfo data_tycons
66 code_stuff = initC cinfo (cgTopBindings maybe_split stg_binds)
67 init_stuff = mkModuleInit fe_binders mod_name imported_modules
70 abstractC = mkAbstractCs [ maybe_split,
74 -- Put datatype_stuff after code_stuff, because the
75 -- datatype closure table (for enumeration types)
76 -- to (say) PrelBase_True_closure, which is defined in code_stuff
78 flat_abstractC = flattenAbsC fl_uniqs abstractC
80 dumpIfSet_dyn dflags Opt_D_dump_absC "Abstract C" (dumpRealC abstractC) >>
84 data_tycons = filter isDataTyCon tycons
86 maybe_split = if opt_EnsureSplittableC
89 cinfo = MkCompInfo mod_name
92 %************************************************************************
94 \subsection[codegen-init]{Module initialisation code}
96 %************************************************************************
100 :: [Id] -- foreign exported functions
101 -> Module -- module name
102 -> [Module] -- import names
103 -> ([CostCentre], -- cost centre info
107 mkModuleInit fe_binders mod imps cost_centre_info
110 map (\f -> CMacroStmt REGISTER_FOREIGN_EXPORT [f]) fe_labels
113 map (\f -> CLbl (mkClosureLabel (idName f)) PtrRep) fe_binders
115 (cc_decls, cc_regs) = mkCostCentreStuff cost_centre_info
117 mk_import_register imp =
118 CMacroStmt REGISTER_IMPORT [
119 CLbl (mkModuleInitLabel imp) AddrRep
122 register_imports = map mk_import_register imps
126 CModuleInitBlock (mkModuleInitLabel mod)
127 (mkAbstractCs (register_fes ++
133 Cost-centre profiling: Besides the usual stuff, we must produce
134 declarations for the cost-centres defined in this module;
136 (The local cost-centres involved in this are passed into the
140 mkCostCentreStuff (local_CCs, extern_CCs, singleton_CCSs)
141 | not opt_SccProfilingOn = (AbsCNop, AbsCNop)
144 map (CCostCentreDecl True) local_CCs ++
145 map (CCostCentreDecl False) extern_CCs ++
146 map CCostCentreStackDecl singleton_CCSs),
147 mkAbstractCs (mkCcRegister local_CCs singleton_CCSs)
150 mkCcRegister ccs cc_stacks
152 register_ccs = mkAbstractCs (map mk_register ccs)
153 register_cc_stacks = mkAbstractCs (map mk_register_ccs cc_stacks)
155 [ register_ccs, register_cc_stacks ]
158 = CCallProfCCMacro SLIT("REGISTER_CC") [mkCCostCentre cc]
161 = CCallProfCCMacro SLIT("REGISTER_CCS") [mkCCostCentreStack ccs]
164 %************************************************************************
166 \subsection[codegen-top-bindings]{Converting top-level STG bindings}
168 %************************************************************************
170 @cgTopBindings@ is only used for top-level bindings, since they need
171 to be allocated statically (not in the heap) and need to be labelled.
172 No unboxed bindings can happen at top level.
174 In the code below, the static bindings are accumulated in the
175 @MkCgState@, and transferred into the ``statics'' slot by @forkStatics@.
176 This is so that we can write the top level processing in a compositional
177 style, with the increasing static environment being plumbed as a state
181 cgTopBindings :: AbstractC -> [(StgBinding,[Id])] -> Code
183 cgTopBindings split bindings = mapCs (cgTopBinding split) bindings
185 cgTopBinding :: AbstractC -> (StgBinding,[Id]) -> Code
187 cgTopBinding split ((StgNonRec name rhs), srt)
189 absC (mkSRT srt_label srt) `thenC`
190 setSRTLabel srt_label (
191 cgTopRhs name rhs `thenFC` \ (name, info) ->
195 srt_label = mkSRTLabel (idName name)
197 cgTopBinding split ((StgRec pairs@((name,rhs):_)), srt)
199 absC (mkSRT srt_label srt) `thenC`
200 setSRTLabel srt_label (
201 fixC (\ new_binds -> addBindsC new_binds `thenC`
202 mapFCs ( \ (b,e) -> cgTopRhs b e ) pairs
203 ) `thenFC` \ new_binds ->
207 srt_label = mkSRTLabel (idName name)
209 mkSRT :: CLabel -> [Id] -> AbstractC
210 mkSRT lbl [] = AbsCNop
211 mkSRT lbl ids = CSRT lbl (map (mkClosureLabel . idName) ids)
213 -- Urgh! I tried moving the forkStatics call from the rhss of cgTopRhs
214 -- to enclose the listFCs in cgTopBinding, but that tickled the
215 -- statics "error" call in initC. I DON'T UNDERSTAND WHY!
217 cgTopRhs :: Id -> StgRhs -> FCode (Id, CgIdInfo)
218 -- the Id is passed along for setting up a binding...
220 cgTopRhs bndr (StgRhsCon cc con args)
221 = forkStatics (cgTopRhsCon bndr con args)
223 cgTopRhs bndr (StgRhsClosure cc bi srt fvs upd_flag args body)
224 = ASSERT(null fvs) -- There should be no free variables
225 getSRTLabel `thenFC` \srt_label ->
227 mkClosureLFInfo bndr TopLevel [{-no fvs-}] upd_flag args srt_label srt
229 forkStatics (cgTopRhsClosure bndr cc bi args body lf_info)