2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
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 #include "HsVersions.h"
20 module CodeGen ( codeGen ) where
28 import AbsCUtils ( mkAbstractCs, mkAbsCStmts )
29 import Bag ( foldBag )
30 import CgBindery ( CgIdInfo )
31 import CgClosure ( cgTopRhsClosure )
32 import CgCon ( cgTopRhsCon )
33 import CgConTbls ( genStaticConBits )
34 import ClosureInfo ( mkClosureLFInfo )
35 import CmdLineOpts ( opt_SccProfilingOn, opt_CompilingGhcInternals,
36 opt_EnsureSplittableC, opt_SccGroup
38 import CStrings ( modnameToC )
39 import FiniteMap ( FiniteMap )
40 import Maybes ( maybeToBool )
41 import PrimRep ( getPrimRepSize, PrimRep(..) )
42 import Util ( panic, assertPanic )
46 codeGen :: FAST_STRING -- module name
47 -> ([CostCentre], -- local cost-centres needing declaring/registering
48 [CostCentre]) -- "extern" cost-centres needing declaring
49 -> [Module] -- import names
50 -> [TyCon] -- tycons with data constructors to convert
51 -> FiniteMap TyCon [(Bool, [Maybe Type])]
52 -- tycon specialisation info
53 -> [StgBinding] -- bindings to convert
54 -> AbstractC -- output
56 codeGen mod_name (local_CCs, extern_CCs) import_names gen_tycons tycon_specs stg_pgm
58 doing_profiling = opt_SccProfilingOn
59 compiling_prelude = opt_CompilingGhcInternals
60 maybe_split = if opt_EnsureSplittableC then CSplitMarker else AbsCNop
61 cinfo = MkCompInfo mod_name
63 if not doing_profiling then
65 genStaticConBits cinfo gen_tycons tycon_specs,
66 initC cinfo (cgTopBindings maybe_split stg_pgm) ]
68 else -- yes, cost-centre profiling:
69 -- Besides the usual stuff, we must produce:
71 -- * Declarations for the cost-centres defined in this module;
72 -- * Code to participate in "registering" all the cost-centres
73 -- in the program (done at startup time when the pgm is run).
75 -- (The local cost-centres involved in this are passed
76 -- into the code-generator, as are the imported-modules' names.)
78 -- Note: we don't register/etc if compiling Prelude bits.
83 else mkAbstractCs [mkAbstractCs (map (CCostCentreDecl True) local_CCs),
84 mkAbstractCs (map (CCostCentreDecl False) extern_CCs),
85 mkCcRegister local_CCs import_names],
87 genStaticConBits cinfo gen_tycons tycon_specs,
88 initC cinfo (cgTopBindings maybe_split stg_pgm) ]
91 grp_name = case opt_SccGroup of
93 Nothing -> mod_name -- default: module name
96 mkCcRegister ccs import_names
98 register_ccs = mkAbstractCs (map mk_register ccs)
100 = foldr (mkAbsCStmts . mk_import_register) AbsCNop import_names
103 CCallProfCCMacro SLIT("START_REGISTER_CCS") [CLitLit (modnameToC (SLIT("_reg") _APPEND_ mod_name)) AddrRep],
106 CCallProfCCMacro SLIT("END_REGISTER_CCS") []
110 = CCallProfCCMacro SLIT("REGISTER_CC") [mkCCostCentre cc]
112 mk_import_register import_name
113 = CCallProfCCMacro SLIT("REGISTER_IMPORT") [CLitLit (modnameToC (SLIT("_reg") _APPEND_ import_name)) AddrRep]
116 %************************************************************************
118 \subsection[codegen-top-bindings]{Converting top-level STG bindings}
120 %************************************************************************
122 @cgTopBindings@ is only used for top-level bindings, since they need
123 to be allocated statically (not in the heap) and need to be labelled.
124 No unboxed bindings can happen at top level.
126 In the code below, the static bindings are accumulated in the
127 @MkCgState@, and transferred into the ``statics'' slot by @forkStatics@.
128 This is so that we can write the top level processing in a compositional
129 style, with the increasing static environment being plumbed as a state
133 cgTopBindings :: AbstractC -> [StgBinding] -> Code
135 cgTopBindings split bindings = mapCs (cgTopBinding split) bindings
137 cgTopBinding :: AbstractC -> StgBinding -> Code
139 cgTopBinding split (StgNonRec name rhs)
141 cgTopRhs name rhs `thenFC` \ (name, info) ->
144 cgTopBinding split (StgRec pairs)
146 fixC (\ new_binds -> addBindsC new_binds `thenC`
147 mapFCs ( \ (b,e) -> cgTopRhs b e ) pairs
148 ) `thenFC` \ new_binds ->
151 -- Urgh! I tried moving the forkStatics call from the rhss of cgTopRhs
152 -- to enclose the listFCs in cgTopBinding, but that tickled the
153 -- statics "error" call in initC. I DON'T UNDERSTAND WHY!
155 cgTopRhs :: Id -> StgRhs -> FCode (Id, CgIdInfo)
156 -- the Id is passed along for setting up a binding...
158 cgTopRhs name (StgRhsCon cc con args)
159 = forkStatics (cgTopRhsCon name con args (all zero_size args))
161 zero_size atom = getPrimRepSize (getArgPrimRep atom) == 0
163 cgTopRhs name (StgRhsClosure cc bi fvs upd_flag args body)
164 = ASSERT(null fvs) -- There should be no free variables
165 forkStatics (cgTopRhsClosure name cc bi args body lf_info)
167 lf_info = mkClosureLFInfo True{-top level-} [{-no fvs-}] upd_flag args