+Constructing the TypeEnv, Instances, Rules from which the ModIface is
+constructed, and which goes on to subsequent modules in --make mode.
+
+Most of the interface file is obtained simply by serialising the
+TypeEnv. One important consequence is that if the *interface file*
+has pragma info if and only if the final TypeEnv does. This is not so
+important for *this* module, but it's essential for ghc --make:
+subsequent compilations must not see (e.g.) the arity if the interface
+file does not contain arity If they do, they'll exploit the arity;
+then the arity might change, but the iface file doesn't change =>
+recompilation does not happen => disaster.
+
+For data types, the final TypeEnv will have a TyThing for the TyCon,
+plus one for each DataCon; the interface file will contain just one
+data type declaration, but it is de-serialised back into a collection
+of TyThings.
+
+%************************************************************************
+%* *
+ Plan A: simpleTidyPgm
+%* *
+%************************************************************************
+
+
+Plan A: mkBootModDetails: omit pragmas, make interfaces small
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+* Ignore the bindings
+
+* Drop all WiredIn things from the TypeEnv
+ (we never want them in interface files)
+
+* Retain all TyCons and Classes in the TypeEnv, to avoid
+ having to find which ones are mentioned in the
+ types of exported Ids
+
+* Trim off the constructors of non-exported TyCons, both
+ from the TyCon and from the TypeEnv
+
+* Drop non-exported Ids from the TypeEnv
+
+* Tidy the types of the DFunIds of Instances,
+ make them into GlobalIds, (they already have External Names)
+ and add them to the TypeEnv
+
+* Tidy the types of the (exported) Ids in the TypeEnv,
+ make them into GlobalIds (they already have External Names)
+
+* Drop rules altogether
+
+* Tidy the bindings, to ensure that the Caf and Arity
+ information is correct for each top-level binder; the
+ code generator needs it. And to ensure that local names have
+ distinct OccNames in case of object-file splitting
+
+\begin{code}
+mkBootModDetails :: HscEnv -> ModGuts -> IO ModDetails
+-- This is Plan A: make a small type env when typechecking only,
+-- or when compiling a hs-boot file, or simply when not using -O
+--
+-- We don't look at the bindings at all -- there aren't any
+-- for hs-boot files
+
+mkBootModDetails hsc_env (ModGuts { mg_module = mod,
+ mg_exports = exports,
+ mg_types = type_env,
+ mg_insts = ispecs })
+ = do { let dflags = hsc_dflags hsc_env
+ ; showPass dflags "Tidy [hoot] type env"
+
+ ; let { ispecs' = tidyInstances tidyExternalId ispecs
+ ; type_env1 = filterNameEnv (not . isWiredInThing) type_env
+ ; type_env2 = mapNameEnv tidyBootThing type_env1
+ ; type_env' = extendTypeEnvWithIds type_env2
+ (map instanceDFunId ispecs')
+ }
+ ; return (ModDetails { md_types = type_env',
+ md_insts = ispecs',
+ md_rules = [],
+ md_exports = exports })
+ }
+ where
+
+isWiredInThing :: TyThing -> Bool
+isWiredInThing thing = isWiredInName (getName thing)
+
+tidyBootThing :: TyThing -> TyThing
+-- Just externalise the Ids; keep everything
+tidyBootThing (AnId id) | isLocalId id = AnId (tidyExternalId id)
+tidyBootThing thing = thing
+
+tidyExternalId :: Id -> Id
+-- Takes an LocalId with an External Name,
+-- makes it into a GlobalId with VanillaIdInfo, and tidies its type
+-- (NB: vanillaIdInfo makes a conservative assumption about Caf-hood.)
+tidyExternalId id
+ = ASSERT2( isLocalId id && isExternalName (idName id), ppr id )
+ mkVanillaGlobal (idName id) (tidyTopType (idType id)) vanillaIdInfo
+\end{code}
+
+
projects / ghc-hetmet.git / blobdiff