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, showPass )
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 = do { showPass dflags "CodeGen"
65 ; fl_uniqs <- mkSplitUniqSupply 'f'
67 datatype_stuff = genStaticConBits cinfo data_tycons
68 code_stuff = initC cinfo (cgTopBindings maybe_split stg_binds)
69 init_stuff = mkModuleInit fe_binders mod_name imported_modules
72 abstractC = mkAbstractCs [ maybe_split,
76 -- Put datatype_stuff after code_stuff, because the
77 -- datatype closure table (for enumeration types)
78 -- to (say) PrelBase_True_closure, which is defined in code_stuff
80 flat_abstractC = flattenAbsC fl_uniqs abstractC
82 ; dumpIfSet_dyn dflags Opt_D_dump_absC "Abstract C" (dumpRealC abstractC)
83 ; return flat_abstractC
86 data_tycons = filter isDataTyCon tycons
88 maybe_split = if opt_EnsureSplittableC
91 cinfo = MkCompInfo mod_name
94 %************************************************************************
96 \subsection[codegen-init]{Module initialisation code}
98 %************************************************************************
102 :: [Id] -- foreign exported functions
103 -> Module -- module name
104 -> [Module] -- import names
105 -> ([CostCentre], -- cost centre info
109 mkModuleInit fe_binders mod imps cost_centre_info
112 map (\f -> CMacroStmt REGISTER_FOREIGN_EXPORT [f]) fe_labels
115 map (\f -> CLbl (mkClosureLabel (idName f)) PtrRep) fe_binders
117 (cc_decls, cc_regs) = mkCostCentreStuff cost_centre_info
119 mk_import_register imp =
120 CMacroStmt REGISTER_IMPORT [
121 CLbl (mkModuleInitLabel imp) AddrRep
124 register_imports = map mk_import_register imps
128 CModuleInitBlock (mkModuleInitLabel mod)
129 (mkAbstractCs (register_fes ++
135 Cost-centre profiling: Besides the usual stuff, we must produce
136 declarations for the cost-centres defined in this module;
138 (The local cost-centres involved in this are passed into the
142 mkCostCentreStuff (local_CCs, extern_CCs, singleton_CCSs)
143 | not opt_SccProfilingOn = (AbsCNop, AbsCNop)
146 map (CCostCentreDecl True) local_CCs ++
147 map (CCostCentreDecl False) extern_CCs ++
148 map CCostCentreStackDecl singleton_CCSs),
149 mkAbstractCs (mkCcRegister local_CCs singleton_CCSs)
152 mkCcRegister ccs cc_stacks
154 register_ccs = mkAbstractCs (map mk_register ccs)
155 register_cc_stacks = mkAbstractCs (map mk_register_ccs cc_stacks)
157 [ register_ccs, register_cc_stacks ]
160 = CCallProfCCMacro SLIT("REGISTER_CC") [mkCCostCentre cc]
163 = CCallProfCCMacro SLIT("REGISTER_CCS") [mkCCostCentreStack ccs]
166 %************************************************************************
168 \subsection[codegen-top-bindings]{Converting top-level STG bindings}
170 %************************************************************************
172 @cgTopBindings@ is only used for top-level bindings, since they need
173 to be allocated statically (not in the heap) and need to be labelled.
174 No unboxed bindings can happen at top level.
176 In the code below, the static bindings are accumulated in the
177 @MkCgState@, and transferred into the ``statics'' slot by @forkStatics@.
178 This is so that we can write the top level processing in a compositional
179 style, with the increasing static environment being plumbed as a state
183 cgTopBindings :: AbstractC -> [(StgBinding,[Id])] -> Code
185 cgTopBindings split bindings = mapCs (cgTopBinding split) bindings
187 cgTopBinding :: AbstractC -> (StgBinding,[Id]) -> Code
189 cgTopBinding split ((StgNonRec name rhs), srt)
191 absC (mkSRT srt_label srt) `thenC`
192 setSRTLabel srt_label (
193 cgTopRhs name rhs `thenFC` \ (name, info) ->
197 srt_label = mkSRTLabel (idName name)
199 cgTopBinding split ((StgRec pairs@((name,rhs):_)), srt)
201 absC (mkSRT srt_label srt) `thenC`
202 setSRTLabel srt_label (
203 fixC (\ new_binds -> addBindsC new_binds `thenC`
204 mapFCs ( \ (b,e) -> cgTopRhs b e ) pairs
205 ) `thenFC` \ new_binds ->
209 srt_label = mkSRTLabel (idName name)
211 mkSRT :: CLabel -> [Id] -> AbstractC
212 mkSRT lbl [] = AbsCNop
213 mkSRT lbl ids = CSRT lbl (map (mkClosureLabel . idName) ids)
215 -- Urgh! I tried moving the forkStatics call from the rhss of cgTopRhs
216 -- to enclose the listFCs in cgTopBinding, but that tickled the
217 -- statics "error" call in initC. I DON'T UNDERSTAND WHY!
219 cgTopRhs :: Id -> StgRhs -> FCode (Id, CgIdInfo)
220 -- the Id is passed along for setting up a binding...
222 cgTopRhs bndr (StgRhsCon cc con args)
223 = forkStatics (cgTopRhsCon bndr con args)
225 cgTopRhs bndr (StgRhsClosure cc bi srt fvs upd_flag args body)
226 = ASSERT(null fvs) -- There should be no free variables
227 getSRTLabel `thenFC` \srt_label ->
229 mkClosureLFInfo bndr TopLevel [{-no fvs-}] upd_flag args srt_label srt
231 forkStatics (cgTopRhsClosure bndr cc bi args body lf_info)