2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1995
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"
23 -- and to make the interface self-sufficient...
24 UniqFM, AbstractC, StgBinding, Id, FiniteMap
32 import CLabelInfo ( modnameToC )
33 import CgClosure ( cgTopRhsClosure )
34 import CgCon ( cgTopRhsCon )
35 import CgConTbls ( genStaticConBits, TCE(..), UniqFM )
36 import ClosureInfo ( LambdaFormInfo, mkClosureLFInfo )
38 import FiniteMap ( FiniteMap )
39 import Maybes ( Maybe(..) )
40 import Pretty -- debugging only
41 import PrimKind ( getKindSize )
46 codeGen :: FAST_STRING -- module name
47 -> ([CostCentre], -- local cost-centres needing declaring/registering
48 [CostCentre]) -- "extern" cost-centres needing declaring
49 -> [FAST_STRING] -- import names
50 -> (GlobalSwitch -> SwitchResult)
51 -- global switch lookup function
52 -> [TyCon] -- tycons with data constructors to convert
53 -> FiniteMap TyCon [(Bool, [Maybe UniType])]
54 -- tycon specialisation info
55 -> PlainStgProgram -- bindings to convert
56 -> AbstractC -- output
58 codeGen mod_name (local_CCs, extern_CCs) import_names sw_lookup_fn gen_tycons tycon_specs stg_pgm
60 switch_is_on = switchIsOn sw_lookup_fn
61 int_switch_set = intSwitchSet sw_lookup_fn
62 doing_profiling = switch_is_on SccProfilingOn
63 compiling_prelude = switch_is_on CompilingPrelude
64 maybe_split = if (switch_is_on (EnsureSplittableC (panic "codeGen:esc")))
68 cinfo = MkCompInfo switch_is_on int_switch_set mod_name
72 pprTrace "codeGen:" (ppCat [
73 (case (switch_is_on StgDoLetNoEscapes) of
74 False -> ppStr "False?"
77 (case (int_switch_set ReturnInRegsThreshold) of
78 Nothing -> ppStr "Nothing!"
79 Just n -> ppCat [ppStr "Just", ppInt n]
81 (case (int_switch_set UnfoldingUseThreshold) of
82 Nothing -> ppStr "Nothing!"
83 Just n -> ppCat [ppStr "Just", ppInt n]
85 (case (int_switch_set UnfoldingCreationThreshold) of
86 Nothing -> ppStr "Nothing!"
87 Just n -> ppCat [ppStr "Just", ppInt n]
91 if not doing_profiling then
93 genStaticConBits cinfo gen_tycons tycon_specs,
94 initC cinfo (cgTopBindings maybe_split stg_pgm) ]
96 else -- yes, cost-centre profiling:
97 -- Besides the usual stuff, we must produce:
99 -- * Declarations for the cost-centres defined in this module;
100 -- * Code to participate in "registering" all the cost-centres
101 -- in the program (done at startup time when the pgm is run).
103 -- (The local cost-centres involved in this are passed
104 -- into the code-generator, as are the imported-modules' names.)
106 -- Note: we don't register/etc if compiling Prelude bits.
111 else mkAbstractCs [mkAbstractCs (map (CCostCentreDecl True) local_CCs),
112 mkAbstractCs (map (CCostCentreDecl False) extern_CCs),
113 mkCcRegister local_CCs import_names],
115 genStaticConBits cinfo gen_tycons tycon_specs,
116 initC cinfo (cgTopBindings maybe_split stg_pgm) ]
119 grp_name = case (stringSwitchSet sw_lookup_fn SccGroup) of
121 Nothing -> mod_name -- default: module name
124 mkCcRegister ccs import_names
126 register_ccs = mkAbstractCs (map mk_register ccs)
127 register_imports = mkAbstractCs (map mk_import_register import_names)
130 CCallProfCCMacro SLIT("START_REGISTER_CCS") [CLitLit (modnameToC (SLIT("_reg") _APPEND_ mod_name)) AddrKind],
133 CCallProfCCMacro SLIT("END_REGISTER_CCS") []
137 = CCallProfCCMacro SLIT("REGISTER_CC") [mkCCostCentre cc]
139 mk_import_register import_name
140 = CCallProfCCMacro SLIT("REGISTER_IMPORT") [CLitLit (modnameToC (SLIT("_reg") _APPEND_ import_name)) AddrKind]
143 %************************************************************************
145 \subsection[codegen-top-bindings]{Converting top-level STG bindings}
147 %************************************************************************
149 @cgTopBindings@ is only used for top-level bindings, since they need
150 to be allocated statically (not in the heap) and need to be labelled.
151 No unboxed bindings can happen at top level.
153 In the code below, the static bindings are accumulated in the
154 @MkCgState@, and transferred into the ``statics'' slot by @forkStatics@.
155 This is so that we can write the top level processing in a compositional
156 style, with the increasing static environment being plumbed as a state
160 cgTopBindings :: AbstractC -> PlainStgProgram -> Code
162 cgTopBindings split bindings = mapCs (cgTopBinding split) bindings
164 cgTopBinding :: AbstractC -> PlainStgBinding -> Code
166 cgTopBinding split (StgNonRec name rhs)
168 cgTopRhs name rhs `thenFC` \ (name, info) ->
171 cgTopBinding split (StgRec pairs)
173 fixC (\ new_binds -> addBindsC new_binds `thenC`
174 mapFCs ( \ (b,e) -> cgTopRhs b e ) pairs
175 ) `thenFC` \ new_binds ->
178 -- Urgh! I tried moving the forkStatics call from the rhss of cgTopRhs
179 -- to enclose the listFCs in cgTopBinding, but that tickled the
180 -- statics "error" call in initC. I DON'T UNDERSTAND WHY!
182 cgTopRhs :: Id -> PlainStgRhs -> FCode (Id, CgIdInfo)
183 -- the Id is passed along for setting up a binding...
185 cgTopRhs name (StgRhsCon cc con args)
186 = forkStatics (cgTopRhsCon name con args (all zero_size args))
188 zero_size atom = getKindSize (getAtomKind atom) == 0
190 cgTopRhs name (StgRhsClosure cc bi fvs upd_flag args body)
191 = ASSERT(null fvs) -- There should be no free variables
192 forkStatics (cgTopRhsClosure name cc bi args body lf_info)
194 lf_info = mkClosureLFInfo True{-top level-} [{-no fvs-}] upd_flag args body