%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[CodeGen]{@CodeGen@: main module of the code generator}
%************************************************************************
\begin{code}
+module CodeGen ( codeGen ) where
+
#include "HsVersions.h"
-module CodeGen ( codeGen ) where
+-- Kludge (??) so that CgExpr is reached via at least one non-SOURCE
+-- import. Before, that wasn't the case, and CM therefore didn't
+-- bother to compile it.
+import CgExpr ( {-NOTHING!-} ) -- DO NOT DELETE THIS IMPORT
+import CgProf
+import CgMonad
+import CgBindery ( CgIdInfo, addBindC, addBindsC, getCgIdInfo,
+ cgIdInfoId )
+import CgClosure ( cgTopRhsClosure )
+import CgCon ( cgTopRhsCon, cgTyCon )
+import CgUtils ( cmmRegOffW, emitRODataLits, cmmNeWord )
-IMP_Ubiq(){-uitous-}
+import CLabel
+import Cmm
+import CmmUtils ( zeroCLit, mkIntCLit, mkLblExpr )
+import PprCmm ( pprCmms )
+import MachOp ( wordRep, MachHint(..) )
import StgSyn
-import CgMonad
-import AbsCSyn
+import PrelNames ( gHC_PRIM, rOOT_MAIN, mAIN, pREL_TOP_HANDLER )
+import Packages ( HomeModules )
+import DynFlags ( DynFlags(..), DynFlag(..), dopt )
+import StaticFlags ( opt_SccProfilingOn )
-import AbsCUtils ( mkAbstractCs, mkAbsCStmts )
-import Bag ( foldBag )
-import CgClosure ( cgTopRhsClosure )
-import CgCon ( cgTopRhsCon )
-import CgConTbls ( genStaticConBits )
-import ClosureInfo ( mkClosureLFInfo )
-import CmdLineOpts ( opt_SccProfilingOn, opt_CompilingPrelude,
- opt_EnsureSplittableC, opt_SccGroup
- )
-import CStrings ( modnameToC )
-import Maybes ( maybeToBool )
-import PrimRep ( getPrimRepSize, PrimRep(..) )
-import Util ( panic, assertPanic )
+import HscTypes ( ForeignStubs(..), TypeEnv, typeEnvTyCons )
+import CostCentre ( CollectedCCs )
+import Id ( Id, idName, setIdName )
+import Name ( nameSrcLoc, nameOccName, nameUnique, isInternalName, mkExternalName )
+import OccName ( mkLocalOcc )
+import TyCon ( TyCon )
+import Module ( Module, mkModule )
+import ErrUtils ( dumpIfSet_dyn, showPass )
+import Panic ( assertPanic )
+
+#ifdef DEBUG
+import Outputable
+#endif
\end{code}
\begin{code}
-codeGen :: FAST_STRING -- module name
- -> ([CostCentre], -- local cost-centres needing declaring/registering
- [CostCentre]) -- "extern" cost-centres needing declaring
- -> [Module] -- import names
- -> [TyCon] -- tycons with data constructors to convert
- -> FiniteMap TyCon [(Bool, [Maybe Type])]
- -- tycon specialisation info
- -> [StgBinding] -- bindings to convert
- -> AbstractC -- output
-
-codeGen mod_name (local_CCs, extern_CCs) import_names gen_tycons tycon_specs stg_pgm
- = let
- doing_profiling = opt_SccProfilingOn
- compiling_prelude = opt_CompilingPrelude
- maybe_split = if maybeToBool (opt_EnsureSplittableC)
- then CSplitMarker
- else AbsCNop
-
- cinfo = MkCompInfo mod_name
- in
- if not doing_profiling then
- mkAbstractCs [
- genStaticConBits cinfo gen_tycons tycon_specs,
- initC cinfo (cgTopBindings maybe_split stg_pgm) ]
-
- else -- yes, cost-centre profiling:
- -- Besides the usual stuff, we must produce:
- --
- -- * Declarations for the cost-centres defined in this module;
- -- * Code to participate in "registering" all the cost-centres
- -- in the program (done at startup time when the pgm is run).
- --
- -- (The local cost-centres involved in this are passed
- -- into the code-generator, as are the imported-modules' names.)
- --
- -- Note: we don't register/etc if compiling Prelude bits.
-
- mkAbstractCs [
- if compiling_prelude
- then AbsCNop
- else mkAbstractCs [mkAbstractCs (map (CCostCentreDecl True) local_CCs),
- mkAbstractCs (map (CCostCentreDecl False) extern_CCs),
- mkCcRegister local_CCs import_names],
-
- genStaticConBits cinfo gen_tycons tycon_specs,
- initC cinfo (cgTopBindings maybe_split stg_pgm) ]
+codeGen :: DynFlags
+ -> HomeModules
+ -> Module
+ -> [TyCon]
+ -> ForeignStubs
+ -> [Module] -- directly-imported modules
+ -> CollectedCCs -- (Local/global) cost-centres needing declaring/registering.
+ -> [(StgBinding,[(Id,[Id])])] -- Bindings to convert, with SRTs
+ -> IO [Cmm] -- Output
+
+codeGen dflags hmods this_mod data_tycons foreign_stubs imported_mods
+ cost_centre_info stg_binds
+ = do
+ { showPass dflags "CodeGen"
+ ; let way = buildTag dflags
+ main_mod = mainModIs dflags
+
+-- Why?
+-- ; mapM_ (\x -> seq x (return ())) data_tycons
+
+ ; code_stuff <- initC dflags hmods this_mod $ do
+ { cmm_binds <- mapM (getCmm . cgTopBinding dflags hmods) stg_binds
+ ; cmm_tycons <- mapM cgTyCon data_tycons
+ ; cmm_init <- getCmm (mkModuleInit dflags hmods way cost_centre_info
+ this_mod main_mod
+ foreign_stubs imported_mods)
+ ; return (cmm_binds ++ concat cmm_tycons ++ [cmm_init])
+ }
+ -- Put datatype_stuff after code_stuff, because the
+ -- datatype closure table (for enumeration types) to
+ -- (say) PrelBase_True_closure, which is defined in
+ -- code_stuff
+
+ ; dumpIfSet_dyn dflags Opt_D_dump_cmm "Cmm" (pprCmms code_stuff)
+
+ ; return code_stuff }
+\end{code}
+
+%************************************************************************
+%* *
+\subsection[codegen-init]{Module initialisation code}
+%* *
+%************************************************************************
+
+/* -----------------------------------------------------------------------------
+ Module initialisation
+
+ The module initialisation code looks like this, roughly:
+
+ FN(__stginit_Foo) {
+ JMP_(__stginit_Foo_1_p)
+ }
+
+ FN(__stginit_Foo_1_p) {
+ ...
+ }
+
+ We have one version of the init code with a module version and the
+ 'way' attached to it. The version number helps to catch cases
+ where modules are not compiled in dependency order before being
+ linked: if a module has been compiled since any modules which depend on
+ it, then the latter modules will refer to a different version in their
+ init blocks and a link error will ensue.
+
+ The 'way' suffix helps to catch cases where modules compiled in different
+ ways are linked together (eg. profiled and non-profiled).
+
+ We provide a plain, unadorned, version of the module init code
+ which just jumps to the version with the label and way attached. The
+ reason for this is that when using foreign exports, the caller of
+ startupHaskell() must supply the name of the init function for the "top"
+ module in the program, and we don't want to require that this name
+ has the version and way info appended to it.
+ -------------------------------------------------------------------------- */
+
+We initialise the module tree by keeping a work-stack,
+ * pointed to by Sp
+ * that grows downward
+ * Sp points to the last occupied slot
+
+
+\begin{code}
+mkModuleInit
+ :: DynFlags
+ -> HomeModules
+ -> String -- the "way"
+ -> CollectedCCs -- cost centre info
+ -> Module
+ -> Module -- name of the Main module
+ -> ForeignStubs
+ -> [Module]
+ -> Code
+mkModuleInit dflags hmods way cost_centre_info this_mod main_mod foreign_stubs imported_mods
+ = do {
+ if opt_SccProfilingOn
+ then do { -- Allocate the static boolean that records if this
+ -- module has been registered already
+ emitData Data [CmmDataLabel moduleRegdLabel,
+ CmmStaticLit zeroCLit]
+
+ ; emitSimpleProc real_init_lbl $ do
+ { ret_blk <- forkLabelledCode ret_code
+
+ ; init_blk <- forkLabelledCode $ do
+ { mod_init_code; stmtC (CmmBranch ret_blk) }
+
+ ; stmtC (CmmCondBranch (cmmNeWord (CmmLit zeroCLit) mod_reg_val)
+ ret_blk)
+ ; stmtC (CmmBranch init_blk)
+ }
+ }
+ else emitSimpleProc real_init_lbl ret_code
+
+ -- Make the "plain" procedure jump to the "real" init procedure
+ ; emitSimpleProc plain_init_lbl jump_to_init
+
+ -- When compiling the module in which the 'main' function lives,
+ -- (that is, this_mod == main_mod)
+ -- we inject an extra stg_init procedure for stg_init_ZCMain, for the
+ -- RTS to invoke. We must consult the -main-is flag in case the
+ -- user specified a different function to Main.main
+ ; whenC (this_mod == main_mod)
+ (emitSimpleProc plain_main_init_lbl jump_to_init)
+ }
where
- -----------------
- grp_name = case opt_SccGroup of
- Just xx -> _PK_ xx
- Nothing -> mod_name -- default: module name
-
- -----------------
- mkCcRegister ccs import_names
- = let
- register_ccs = mkAbstractCs (map mk_register ccs)
- register_imports
- = foldr (mkAbsCStmts . mk_import_register) AbsCNop import_names
- in
- mkAbstractCs [
- CCallProfCCMacro SLIT("START_REGISTER_CCS") [CLitLit (modnameToC (SLIT("_reg") _APPEND_ mod_name)) AddrRep],
- register_ccs,
- register_imports,
- CCallProfCCMacro SLIT("END_REGISTER_CCS") []
- ]
- where
- mk_register cc
- = CCallProfCCMacro SLIT("REGISTER_CC") [mkCCostCentre cc]
-
- mk_import_register import_name
- = CCallProfCCMacro SLIT("REGISTER_IMPORT") [CLitLit (modnameToC (SLIT("_reg") _APPEND_ import_name)) AddrRep]
+ plain_init_lbl = mkPlainModuleInitLabel hmods this_mod
+ real_init_lbl = mkModuleInitLabel hmods this_mod way
+ plain_main_init_lbl = mkPlainModuleInitLabel hmods rOOT_MAIN
+
+ jump_to_init = stmtC (CmmJump (mkLblExpr real_init_lbl) [])
+
+ mod_reg_val = CmmLoad (mkLblExpr moduleRegdLabel) wordRep
+
+ -- Main refers to GHC.TopHandler.runIO, so make sure we call the
+ -- init function for GHC.TopHandler.
+ extra_imported_mods
+ | this_mod == main_mod = [pREL_TOP_HANDLER]
+ | otherwise = []
+
+ mod_init_code = do
+ { -- Set mod_reg to 1 to record that we've been here
+ stmtC (CmmStore (mkLblExpr moduleRegdLabel) (CmmLit (mkIntCLit 1)))
+
+ -- Now do local stuff
+ ; initCostCentres cost_centre_info
+ ; mapCs (registerModuleImport hmods way)
+ (imported_mods++extra_imported_mods)
+ }
+
+ -- The return-code pops the work stack by
+ -- incrementing Sp, and then jumpd to the popped item
+ ret_code = stmtsC [ CmmAssign spReg (cmmRegOffW spReg 1)
+ , CmmJump (CmmLoad (cmmRegOffW spReg (-1)) wordRep) [] ]
+
+-----------------------
+registerModuleImport :: HomeModules -> String -> Module -> Code
+registerModuleImport hmods way mod
+ | mod == gHC_PRIM
+ = nopC
+ | otherwise -- Push the init procedure onto the work stack
+ = stmtsC [ CmmAssign spReg (cmmRegOffW spReg (-1))
+ , CmmStore (CmmReg spReg) (mkLblExpr (mkModuleInitLabel hmods mod way)) ]
+\end{code}
+
+
+
+Cost-centre profiling: Besides the usual stuff, we must produce
+declarations for the cost-centres defined in this module;
+
+(The local cost-centres involved in this are passed into the
+code-generator.)
+
+\begin{code}
+initCostCentres :: CollectedCCs -> Code
+-- Emit the declarations, and return code to register them
+initCostCentres (local_CCs, ___extern_CCs, singleton_CCSs)
+ | not opt_SccProfilingOn = nopC
+ | otherwise
+ = do { mapM_ emitCostCentreDecl local_CCs
+ ; mapM_ emitCostCentreStackDecl singleton_CCSs
+ ; mapM_ emitRegisterCC local_CCs
+ ; mapM_ emitRegisterCCS singleton_CCSs
+ }
\end{code}
%************************************************************************
%* *
%************************************************************************
-@cgTopBindings@ is only used for top-level bindings, since they need
+@cgTopBinding@ is only used for top-level bindings, since they need
to be allocated statically (not in the heap) and need to be labelled.
No unboxed bindings can happen at top level.
variable.
\begin{code}
-cgTopBindings :: AbstractC -> [StgBinding] -> Code
-
-cgTopBindings split bindings = mapCs (cgTopBinding split) bindings
+cgTopBinding :: DynFlags -> HomeModules -> (StgBinding,[(Id,[Id])]) -> Code
+cgTopBinding dflags hmods (StgNonRec id rhs, srts)
+ = do { id' <- maybeExternaliseId dflags id
+ ; mapM_ (mkSRT hmods [id']) srts
+ ; (id,info) <- cgTopRhs id' rhs
+ ; addBindC id info -- Add the *un-externalised* Id to the envt,
+ -- so we find it when we look up occurrences
+ }
-cgTopBinding :: AbstractC -> StgBinding -> Code
+cgTopBinding dflags hmods (StgRec pairs, srts)
+ = do { let (bndrs, rhss) = unzip pairs
+ ; bndrs' <- mapFCs (maybeExternaliseId dflags) bndrs
+ ; let pairs' = zip bndrs' rhss
+ ; mapM_ (mkSRT hmods bndrs') srts
+ ; _new_binds <- fixC (\ new_binds -> do
+ { addBindsC new_binds
+ ; mapFCs ( \ (b,e) -> cgTopRhs b e ) pairs' })
+ ; nopC }
-cgTopBinding split (StgNonRec name rhs)
- = absC split `thenC`
- cgTopRhs name rhs `thenFC` \ (name, info) ->
- addBindC name info
-
-cgTopBinding split (StgRec pairs)
- = absC split `thenC`
- fixC (\ new_binds -> addBindsC new_binds `thenC`
- mapFCs ( \ (b,e) -> cgTopRhs b e ) pairs
- ) `thenFC` \ new_binds ->
- addBindsC new_binds
+mkSRT :: HomeModules -> [Id] -> (Id,[Id]) -> Code
+mkSRT hmods these (id,[]) = nopC
+mkSRT hmods these (id,ids)
+ = do { ids <- mapFCs remap ids
+ ; id <- remap id
+ ; emitRODataLits (mkSRTLabel (idName id))
+ (map (CmmLabel . mkClosureLabel hmods . idName) ids)
+ }
+ where
+ -- Sigh, better map all the ids against the environment in
+ -- case they've been externalised (see maybeExternaliseId below).
+ remap id = case filter (==id) these of
+ (id':_) -> returnFC id'
+ [] -> do { info <- getCgIdInfo id; return (cgIdInfoId info) }
-- Urgh! I tried moving the forkStatics call from the rhss of cgTopRhs
-- to enclose the listFCs in cgTopBinding, but that tickled the
-- statics "error" call in initC. I DON'T UNDERSTAND WHY!
cgTopRhs :: Id -> StgRhs -> FCode (Id, CgIdInfo)
- -- the Id is passed along for setting up a binding...
+ -- The Id is passed along for setting up a binding...
+ -- It's already been externalised if necessary
+
+cgTopRhs bndr (StgRhsCon cc con args)
+ = forkStatics (cgTopRhsCon bndr con args)
+
+cgTopRhs bndr (StgRhsClosure cc bi fvs upd_flag srt args body)
+ = ASSERT(null fvs) -- There should be no free variables
+ setSRTLabel (mkSRTLabel (idName bndr)) $
+ forkStatics (cgTopRhsClosure bndr cc bi srt upd_flag args body)
+\end{code}
-cgTopRhs name (StgRhsCon cc con args)
- = forkStatics (cgTopRhsCon name con args (all zero_size args))
- where
- zero_size atom = getPrimRepSize (getArgPrimRep atom) == 0
-cgTopRhs name (StgRhsClosure cc bi fvs upd_flag args body)
- = ASSERT(null fvs) -- There should be no free variables
- forkStatics (cgTopRhsClosure name cc bi args body lf_info)
+%************************************************************************
+%* *
+\subsection{Stuff to support splitting}
+%* *
+%************************************************************************
+
+If we're splitting the object, we need to externalise all the top-level names
+(and then make sure we only use the externalised one in any C label we use
+which refers to this name).
+
+\begin{code}
+maybeExternaliseId :: DynFlags -> Id -> FCode Id
+maybeExternaliseId dflags id
+ | dopt Opt_SplitObjs dflags, -- Externalise the name for -split-objs
+ isInternalName name = do { mod <- moduleName
+ ; returnFC (setIdName id (externalise mod)) }
+ | otherwise = returnFC id
where
- lf_info = mkClosureLFInfo True{-top level-} [{-no fvs-}] upd_flag args body
+ externalise mod = mkExternalName uniq mod new_occ Nothing loc
+ name = idName id
+ uniq = nameUnique name
+ new_occ = mkLocalOcc uniq (nameOccName name)
+ loc = nameSrcLoc name
+ -- We want to conjure up a name that can't clash with any
+ -- existing name. So we generate
+ -- Mod_$L243foo
+ -- where 243 is the unique.
\end{code}