%
% (c) The AQUA Project, Glasgow University, 1996-1998
%
-%************************************************************************
-%* *
-\section[PprCore]{Printing of Core syntax, including for interfaces}
-%* *
-%************************************************************************
\begin{code}
module CoreTidy (
- tidyBind, tidyExpr,
- tidyBndr, tidyBndrs, tidyVarOcc,
- tidyIdRules, pprTidyIdRules
+ tidyExpr, tidyVarOcc, tidyRule, tidyRules
) where
#include "HsVersions.h"
import CoreSyn
import CoreUtils ( exprArity )
-import PprCore ( pprIdRules )
-import Id ( Id, mkUserLocal, idInfo, setIdInfo, idUnique, idType, idCoreRules )
-import IdInfo ( vanillaIdInfo, setArityInfo,
+import Unify ( coreRefineTys )
+import DataCon ( DataCon, isVanillaDataCon )
+import Id ( Id, mkUserLocal, idInfo, setIdInfo, idUnique,
+ idType, setIdType )
+import IdInfo ( setArityInfo, vanillaIdInfo,
newStrictnessInfo, setAllStrictnessInfo,
newDemandInfo, setNewDemandInfo )
-import Type ( tidyType, tidyTyVarBndr )
-import Var ( Var )
+import Type ( Type, tidyType, tidyTyVarBndr, substTy, mkOpenTvSubst )
+import Var ( Var, TyVar, varName )
import VarEnv
-import Name ( getOccName )
+import UniqFM ( lookupUFM )
+import Name ( Name, getOccName )
import OccName ( tidyOccName )
import SrcLoc ( noSrcLoc )
import Maybes ( orElse )
\end{code}
+This module contains "tidying" code for *nested* expressions, bindings, rules.
+The code for *top-level* bindings is in TidyPgm.
+
%************************************************************************
%* *
\subsection{Tidying expressions, rules}
-> (TidyEnv, CoreBind)
tidyBind env (NonRec bndr rhs)
- = tidyLetBndr env (bndr,rhs) =: \ (env', bndr') ->
+ = tidyLetBndr env (bndr,rhs) =: \ (env', bndr') ->
(env', NonRec bndr' (tidyExpr env' rhs))
tidyBind env (Rec prs)
- = mapAccumL tidyLetBndr env prs =: \ (env', bndrs') ->
+ = mapAccumL tidyLetBndr env prs =: \ (env', bndrs') ->
map (tidyExpr env') (map snd prs) =: \ rhss' ->
(env', Rec (zip bndrs' rhss'))
------------ Expressions --------------
-tidyCoreExpr :: CoreExpr -> IO CoreExpr
-tidyCoreExpr expr = return (tidyExpr emptyTidyEnv expr)
-
+tidyExpr :: TidyEnv -> CoreExpr -> CoreExpr
tidyExpr env (Var v) = Var (tidyVarOcc env v)
tidyExpr env (Type ty) = Type (tidyType env ty)
tidyExpr env (Lit lit) = Lit lit
= tidyBind env b =: \ (env', b') ->
Let b' (tidyExpr env' e)
-tidyExpr env (Case e b alts)
+tidyExpr env (Case e b ty alts)
= tidyBndr env b =: \ (env', b) ->
- Case (tidyExpr env e) b (map (tidyAlt env') alts)
+ Case (tidyExpr env e) b (tidyType env ty)
+ (map (tidyAlt b env') alts)
tidyExpr env (Lam b e)
= tidyBndr env b =: \ (env', b) ->
Lam b (tidyExpr env' e)
------------ Case alternatives --------------
-tidyAlt env (con, vs, rhs)
+tidyAlt case_bndr env (DataAlt con, vs, rhs)
+ | not (isVanillaDataCon con) -- GADT case
+ = tidyBndrs env tvs =: \ (env1, tvs') ->
+ let
+ env2 = refineTidyEnv env con tvs' scrut_ty
+ in
+ tidyBndrs env2 ids =: \ (env3, ids') ->
+ (DataAlt con, tvs' ++ ids', tidyExpr env3 rhs)
+ where
+ (tvs, ids) = span isTyVar vs
+ scrut_ty = idType case_bndr
+
+tidyAlt case_bndr env (con, vs, rhs)
= tidyBndrs env vs =: \ (env', vs) ->
(con, vs, tidyExpr env' rhs)
+refineTidyEnv :: TidyEnv -> DataCon -> [TyVar] -> Type -> TidyEnv
+-- Refine the TidyEnv in the light of the type refinement from coreRefineTys
+refineTidyEnv tidy_env@(occ_env, var_env) con tvs scrut_ty
+ = case coreRefineTys con tvs scrut_ty of
+ Nothing -> tidy_env
+ Just (tv_subst, all_bound_here)
+ | all_bound_here -- Local type refinement only
+ -> tidy_env
+ | otherwise -- Apply the refining subst to the tidy env
+ -- This ensures that occurences have the most refined type
+ -- And that means that exprType will work right everywhere
+ -> (occ_env, mapVarEnv (refine subst) var_env)
+ where
+ subst = mkOpenTvSubst tv_subst
+ where
+ refine subst var | isId var = setIdType var (substTy subst (idType var))
+ | otherwise = var
+
------------ Notes --------------
tidyNote env (Coerce t1 t2) = Coerce (tidyType env t1) (tidyType env t2)
tidyNote env note = note
-
------------ Rules --------------
-tidyIdRules :: TidyEnv -> [IdCoreRule] -> [IdCoreRule]
-tidyIdRules env [] = []
-tidyIdRules env ((fn,rule) : rules)
+tidyRules :: TidyEnv -> [CoreRule] -> [CoreRule]
+tidyRules env [] = []
+tidyRules env (rule : rules)
= tidyRule env rule =: \ rule ->
- tidyIdRules env rules =: \ rules ->
- ((tidyVarOcc env fn, rule) : rules)
+ tidyRules env rules =: \ rules ->
+ (rule : rules)
tidyRule :: TidyEnv -> CoreRule -> CoreRule
-tidyRule env rule@(BuiltinRule _ _) = rule
-tidyRule env (Rule name act vars tpl_args rhs)
- = tidyBndrs env vars =: \ (env', vars) ->
- map (tidyExpr env') tpl_args =: \ tpl_args ->
- (Rule name act vars tpl_args (tidyExpr env' rhs))
-
-pprTidyIdRules :: Id -> SDoc
-pprTidyIdRules id = pprIdRules (tidyIdRules emptyTidyEnv (idCoreRules id))
+tidyRule env rule@(BuiltinRule {}) = rule
+tidyRule env rule@(Rule { ru_bndrs = bndrs, ru_args = args, ru_rhs = rhs,
+ ru_fn = fn, ru_rough = mb_ns })
+ = tidyBndrs env bndrs =: \ (env', bndrs) ->
+ map (tidyExpr env') args =: \ args ->
+ rule { ru_bndrs = bndrs, ru_args = args,
+ ru_rhs = tidyExpr env' rhs,
+ ru_fn = tidyNameOcc env fn,
+ ru_rough = map (fmap (tidyNameOcc env')) mb_ns }
\end{code}
%************************************************************************
\begin{code}
+tidyNameOcc :: TidyEnv -> Name -> Name
+-- In rules and instances, we have Names, and we must tidy them too
+-- Fortunately, we can lookup in the VarEnv with a name
+tidyNameOcc (_, var_env) n = case lookupUFM var_env n of
+ Nothing -> n
+ Just v -> varName v
+
tidyVarOcc :: TidyEnv -> Var -> Var
tidyVarOcc (_, var_env) v = lookupVarEnv var_env v `orElse` v
where
((tidy_env,var_env), new_id) = tidyIdBndr env id
- -- We need to keep around any interesting strictness and demand info
- -- because later on we may need to use it when converting to A-normal form.
+ -- We need to keep around any interesting strictness and
+ -- demand info because later on we may need to use it when
+ -- converting to A-normal form.
-- eg.
-- f (g x), where f is strict in its argument, will be converted
-- into case (g x) of z -> f z by CorePrep, but only if f still
-- CorePrep to turn the let into a case.
--
-- Similarly arity info for eta expansion in CorePrep
+ --
final_id = new_id `setIdInfo` new_info
idinfo = idInfo id
- new_info = vanillaIdInfo
+ new_info = vanillaIdInfo
`setArityInfo` exprArity rhs
`setAllStrictnessInfo` newStrictnessInfo idinfo
`setNewDemandInfo` newDemandInfo idinfo
-- The SrcLoc isn't important now,
-- though we could extract it from the Id
--
- -- All nested Ids now have the same IdInfo, namely none,
+ -- All nested Ids now have the same IdInfo, namely vanillaIdInfo,
-- which should save some space.
-- But note that tidyLetBndr puts some of it back.
ty' = tidyType env (idType id)
id' = mkUserLocal occ' (idUnique id) ty' noSrcLoc
+ `setIdInfo` vanillaIdInfo
var_env' = extendVarEnv var_env id id'
in
((tidy_env', var_env'), id')
\begin{code}
m =: k = m `seq` k m
\end{code}
-
-
projects / ghc-hetmet.git / blobdiff