X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FInst.lhs;h=c16ba2c541636b49a2406bd52ba09376f0b88a20;hb=6858f7c15fcf9efe9e6fdf22de34d0791b0f0c08;hp=762cdecb4817608375e0f5adf80bd47ab085c993;hpb=5e6242927839c8ddc73a55eb7828c0b7e4cc3ab2;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/Inst.lhs b/ghc/compiler/typecheck/Inst.lhs index 762cdec..c16ba2c 100644 --- a/ghc/compiler/typecheck/Inst.lhs +++ b/ghc/compiler/typecheck/Inst.lhs @@ -9,15 +9,15 @@ module Inst ( plusLIEs, mkLIE, isEmptyLIE, lieToList, listToLIE, Inst, - pprInst, pprInsts, pprInstsInFull, tidyInst, tidyInsts, + pprInst, pprInsts, pprInstsInFull, tidyInsts, tidyMoreInsts, - newDictsFromOld, newDicts, newClassDicts, + newDictsFromOld, newDicts, newMethod, newMethodWithGivenTy, newOverloadedLit, newIPDict, tcInstId, tyVarsOfInst, tyVarsOfInsts, tyVarsOfLIE, instLoc, getDictClassTys, getIPs, - predsOfInsts, + predsOfInsts, predsOfInst, lookupInst, lookupSimpleInst, LookupInstResult(..), @@ -25,8 +25,8 @@ module Inst ( isTyVarDict, isStdClassTyVarDict, isMethodFor, instBindingRequired, instCanBeGeneralised, - zonkInst, zonkInsts, - instToId, + zonkInst, zonkInsts, + instToId, instName, InstOrigin(..), InstLoc, pprInstLoc ) where @@ -39,40 +39,39 @@ import TcHsSyn ( TcExpr, TcId, mkHsTyApp, mkHsDictApp, mkHsConApp, zonkId ) import TcMonad -import TcEnv ( TcIdSet, tcGetInstEnv, tcLookupSyntaxId ) +import TcEnv ( TcIdSet, tcGetInstEnv, tcLookupId ) import InstEnv ( InstLookupResult(..), lookupInstEnv ) -import TcType ( TcThetaType, TcClassContext, - TcType, TcTauType, TcTyVarSet, - zonkTcType, zonkTcTypes, - zonkTcThetaType, tcInstTyVar, tcInstType +import TcMType ( zonkTcType, zonkTcTypes, zonkTcPredType, + zonkTcThetaType, tcInstTyVar, tcInstType, + ) +import TcType ( Type, + SourceType(..), PredType, ThetaType, + tcSplitForAllTys, tcSplitForAllTys, + tcSplitMethodTy, tcSplitRhoTy, tcFunArgTy, + isIntTy,isFloatTy, isIntegerTy, isDoubleTy, + tcIsTyVarTy, mkPredTy, mkTyVarTy, mkTyVarTys, + tyVarsOfType, tyVarsOfTypes, tyVarsOfPred, tidyPred, + predMentionsIPs, isClassPred, isTyVarClassPred, + getClassPredTys, getClassPredTys_maybe, mkPredName, + tidyType, tidyTypes, tidyFreeTyVars, + tcCmpType, tcCmpTypes, tcCmpPred ) import CoreFVs ( idFreeTyVars ) import Class ( Class ) -import Id ( Id, idType, mkUserLocal, mkSysLocal, mkVanillaId ) +import Id ( Id, idName, idType, mkUserLocal, mkSysLocal, mkLocalId ) import PrelInfo ( isStandardClass, isCcallishClass, isNoDictClass ) -import Name ( mkDictOcc, mkMethodOcc, getOccName, mkLocalName ) +import Name ( Name, mkMethodOcc, getOccName ) import NameSet ( NameSet ) import PprType ( pprPred ) -import Type ( Type, PredType(..), - isTyVarTy, mkPredTy, mkTyVarTy, mkTyVarTys, - splitForAllTys, splitSigmaTy, funArgTy, - splitMethodTy, splitRhoTy, classesOfPreds, - tyVarsOfType, tyVarsOfTypes, tyVarsOfPred, - tidyOpenType, tidyOpenTypes, predMentionsIPs - ) import Subst ( emptyInScopeSet, mkSubst, - substTy, substClasses, mkTyVarSubst, mkTopTyVarSubst + substTy, substTyWith, substTheta, mkTyVarSubst, mkTopTyVarSubst ) import Literal ( inIntRange ) import VarEnv ( TidyEnv, lookupSubstEnv, SubstResult(..) ) import VarSet ( elemVarSet, emptyVarSet, unionVarSet ) -import TysWiredIn ( isIntTy, - floatDataCon, isFloatTy, - doubleDataCon, isDoubleTy, - isIntegerTy - ) -import PrelNames( fromIntName, fromIntegerName, fromRationalName ) -import Util ( thenCmp, zipWithEqual, mapAccumL ) +import TysWiredIn ( floatDataCon, doubleDataCon ) +import PrelNames( fromIntegerName, fromRationalName ) +import Util ( thenCmp ) import Bag import Outputable \end{code} @@ -100,7 +99,7 @@ zonkLIE :: LIE -> NF_TcM LIE zonkLIE lie = mapBagNF_Tc zonkInst lie pprInsts :: [Inst] -> SDoc -pprInsts insts = parens (sep (punctuate comma (map pprInst insts))) +pprInsts insts = parens (sep (punctuate comma (map pprInst insts))) pprInstsInFull insts @@ -176,14 +175,14 @@ instance Eq Inst where EQ -> True other -> False -cmpInst (Dict _ pred1 _) (Dict _ pred2 _) = (pred1 `compare` pred2) +cmpInst (Dict _ pred1 _) (Dict _ pred2 _) = pred1 `tcCmpPred` pred2 cmpInst (Dict _ _ _) other = LT cmpInst (Method _ _ _ _ _ _) (Dict _ _ _) = GT -cmpInst (Method _ id1 tys1 _ _ _) (Method _ id2 tys2 _ _ _) = (id1 `compare` id2) `thenCmp` (tys1 `compare` tys2) +cmpInst (Method _ id1 tys1 _ _ _) (Method _ id2 tys2 _ _ _) = (id1 `compare` id2) `thenCmp` (tys1 `tcCmpTypes` tys2) cmpInst (Method _ _ _ _ _ _) other = LT -cmpInst (LitInst _ lit1 ty1 _) (LitInst _ lit2 ty2 _) = (lit1 `compare` lit2) `thenCmp` (ty1 `compare` ty2) +cmpInst (LitInst _ lit1 ty1 _) (LitInst _ lit2 ty2 _) = (lit1 `compare` lit2) `thenCmp` (ty1 `tcCmpType` ty2) cmpInst (LitInst _ _ _ _) other = GT -- and they can only have HsInt or HsFracs in them. @@ -193,6 +192,9 @@ cmpInst (LitInst _ _ _ _) other = GT Selection ~~~~~~~~~ \begin{code} +instName :: Inst -> Name +instName inst = idName (instToId inst) + instToId :: Inst -> TcId instToId (Dict id _ _) = id instToId (Method id _ _ _ _ _) = id @@ -202,7 +204,7 @@ instLoc (Dict _ _ loc) = loc instLoc (Method _ _ _ _ _ loc) = loc instLoc (LitInst _ _ _ loc) = loc -getDictClassTys (Dict _ (Class clas tys) _) = (clas, tys) +getDictClassTys (Dict _ pred _) = getClassPredTys pred predsOfInsts :: [Inst] -> [PredType] predsOfInsts insts = concatMap predsOfInst insts @@ -238,8 +240,12 @@ isDict (Dict _ _ _) = True isDict other = False isClassDict :: Inst -> Bool -isClassDict (Dict _ (Class _ _) _) = True -isClassDict other = False +isClassDict (Dict _ pred _) = isClassPred pred +isClassDict other = False + +isTyVarDict :: Inst -> Bool +isTyVarDict (Dict _ pred _) = isTyVarClassPred pred +isTyVarDict other = False isMethod :: Inst -> Bool isMethod (Method _ _ _ _ _ _) = True @@ -256,14 +262,9 @@ instMentionsIPs (Dict _ pred _) ip_names = pred `predMentionsIPs` ip_na instMentionsIPs (Method _ _ _ theta _ _) ip_names = any (`predMentionsIPs` ip_names) theta instMentionsIPs other ip_names = False -isTyVarDict :: Inst -> Bool -isTyVarDict (Dict _ (Class _ tys) _) = all isTyVarTy tys -isTyVarDict other = False - -isStdClassTyVarDict (Dict _ (Class clas [ty]) _) - = isStandardClass clas && isTyVarTy ty -isStdClassTyVarDict other - = False +isStdClassTyVarDict (Dict _ pred _) = case getClassPredTys_maybe pred of + Just (clas, [ty]) -> isStandardClass clas && tcIsTyVarTy ty + other -> False \end{code} Two predicates which deal with the case where class constraints don't @@ -273,13 +274,13 @@ must be witnessed by an actual binding; the second tells whether an \begin{code} instBindingRequired :: Inst -> Bool -instBindingRequired (Dict _ (Class clas _) _) = not (isNoDictClass clas) -instBindingRequired (Dict _ (IParam _ _) _) = False -instBindingRequired other = True +instBindingRequired (Dict _ (ClassP clas _) _) = not (isNoDictClass clas) +instBindingRequired (Dict _ (IParam _ _) _) = False +instBindingRequired other = True instCanBeGeneralised :: Inst -> Bool -instCanBeGeneralised (Dict _ (Class clas _) _) = not (isCcallishClass clas) -instCanBeGeneralised other = True +instCanBeGeneralised (Dict _ (ClassP clas _) _) = not (isCcallishClass clas) +instCanBeGeneralised other = True \end{code} @@ -297,13 +298,8 @@ newDicts orig theta = tcGetInstLoc orig `thenNF_Tc` \ loc -> newDictsAtLoc loc theta -newClassDicts :: InstOrigin - -> TcClassContext - -> NF_TcM [Inst] -newClassDicts orig theta = newDicts orig (map (uncurry Class) theta) - -newDictsFromOld :: Inst -> TcClassContext -> NF_TcM [Inst] -newDictsFromOld (Dict _ _ loc) theta = newDictsAtLoc loc (map (uncurry Class) theta) +newDictsFromOld :: Inst -> TcThetaType -> NF_TcM [Inst] +newDictsFromOld (Dict _ _ loc) theta = newDictsAtLoc loc theta -- Local function, similar to newDicts, -- but with slightly different interface @@ -311,17 +307,17 @@ newDictsAtLoc :: InstLoc -> TcThetaType -> NF_TcM [Inst] newDictsAtLoc inst_loc@(_,loc,_) theta - = tcGetUniques (length theta) `thenNF_Tc` \ new_uniqs -> - returnNF_Tc (zipWithEqual "newDictsAtLoc" mk_dict new_uniqs theta) + = tcGetUniques `thenNF_Tc` \ new_uniqs -> + returnNF_Tc (zipWith mk_dict new_uniqs theta) where - mk_dict uniq pred = Dict (mkVanillaId (mk_dict_name uniq pred) (mkPredTy pred)) pred inst_loc - - mk_dict_name uniq (Class cls tys) = mkLocalName uniq (mkDictOcc (getOccName cls)) loc - mk_dict_name uniq (IParam name ty) = name + mk_dict uniq pred = Dict (mkLocalId (mkPredName uniq loc pred) (mkPredTy pred)) pred inst_loc +-- For implicit parameters, since there is only one in scope +-- at any time, we use the name of the implicit parameter itself newIPDict orig name ty = tcGetInstLoc orig `thenNF_Tc` \ inst_loc -> - returnNF_Tc (Dict (mkVanillaId name ty) (IParam name ty) inst_loc) + returnNF_Tc (Dict (mkLocalId name (mkPredTy pred)) pred inst_loc) + where pred = IParam name ty \end{code} @@ -394,9 +390,9 @@ newMethod :: InstOrigin newMethod orig id tys = -- Get the Id type and instantiate it at the specified types let - (tyvars, rho) = splitForAllTys (idType id) - rho_ty = substTy (mkTyVarSubst tyvars tys) rho - (pred, tau) = splitMethodTy rho_ty + (tyvars, rho) = tcSplitForAllTys (idType id) + rho_ty = substTyWith tyvars tys rho + (pred, tau) = tcSplitMethodTy rho_ty in newMethodWithGivenTy orig id tys [pred] tau @@ -418,10 +414,10 @@ newMethodAtLoc inst_loc real_id tys -- This actually builds the Inst = -- Get the Id type and instantiate it at the specified types let - (tyvars,rho) = splitForAllTys (idType real_id) + (tyvars,rho) = tcSplitForAllTys (idType real_id) rho_ty = ASSERT( length tyvars == length tys ) substTy (mkTopTyVarSubst tyvars tys) rho - (theta, tau) = splitRhoTy rho_ty + (theta, tau) = tcSplitRhoTy rho_ty in newMethodWith inst_loc real_id tys theta tau `thenNF_Tc` \ meth_inst -> returnNF_Tc (meth_inst, instToId meth_inst) @@ -437,18 +433,11 @@ newOverloadedLit :: InstOrigin -> HsOverLit -> TcType -> NF_TcM (TcExpr, LIE) -newOverloadedLit orig (HsIntegral i) ty - | isIntTy ty && inIntRange i -- Short cut for Int - = returnNF_Tc (int_lit, emptyLIE) - - | isIntegerTy ty -- Short cut for Integer - = returnNF_Tc (integer_lit, emptyLIE) - - where - int_lit = HsLit (HsInt i) - integer_lit = HsLit (HsInteger i) +newOverloadedLit orig lit ty + | Just expr <- shortCutLit lit ty + = returnNF_Tc (expr, emptyLIE) -newOverloadedLit orig lit ty -- The general case + | otherwise = tcGetInstLoc orig `thenNF_Tc` \ loc -> tcGetUnique `thenNF_Tc` \ new_uniq -> let @@ -456,6 +445,22 @@ newOverloadedLit orig lit ty -- The general case lit_id = mkSysLocal SLIT("lit") new_uniq ty in returnNF_Tc (HsVar (instToId lit_inst), unitLIE lit_inst) + +shortCutLit :: HsOverLit -> TcType -> Maybe TcExpr +shortCutLit (HsIntegral i fi) ty + | isIntTy ty && inIntRange i && fi == fromIntegerName -- Short cut for Int + = Just (HsLit (HsInt i)) + | isIntegerTy ty && fi == fromIntegerName -- Short cut for Integer + = Just (HsLit (HsInteger i)) + +shortCutLit (HsFractional f fr) ty + | isFloatTy ty && fr == fromRationalName + = Just (mkHsConApp floatDataCon [] [HsLit (HsFloatPrim f)]) + | isDoubleTy ty && fr == fromRationalName + = Just (mkHsConApp doubleDataCon [] [HsLit (HsDoublePrim f)]) + +shortCutLit lit ty + = Nothing \end{code} @@ -470,17 +475,9 @@ but doesn't do the same for any of the Ids in an Inst. There's no need, and it's a lot of extra work. \begin{code} -zonkPred :: TcPredType -> NF_TcM TcPredType -zonkPred (Class clas tys) - = zonkTcTypes tys `thenNF_Tc` \ new_tys -> - returnNF_Tc (Class clas new_tys) -zonkPred (IParam n ty) - = zonkTcType ty `thenNF_Tc` \ new_ty -> - returnNF_Tc (IParam n new_ty) - zonkInst :: Inst -> NF_TcM Inst zonkInst (Dict id pred loc) - = zonkPred pred `thenNF_Tc` \ new_pred -> + = zonkTcPredType pred `thenNF_Tc` \ new_pred -> returnNF_Tc (Dict id new_pred loc) zonkInst (Method m id tys theta tau loc) @@ -528,36 +525,23 @@ pprInst m@(Method u id tys theta tau loc) show_uniq u, ppr (instToId m) -}] -tidyPred :: TidyEnv -> TcPredType -> (TidyEnv, TcPredType) -tidyPred env (Class clas tys) - = (env', Class clas tys') - where - (env', tys') = tidyOpenTypes env tys -tidyPred env (IParam n ty) - = (env', IParam n ty') - where - (env', ty') = tidyOpenType env ty - -tidyInst :: TidyEnv -> Inst -> (TidyEnv, Inst) -tidyInst env (LitInst u lit ty loc) - = (env', LitInst u lit ty' loc) - where - (env', ty') = tidyOpenType env ty +show_uniq u = ifPprDebug (text "{-" <> ppr u <> text "-}") -tidyInst env (Dict u pred loc) - = (env', Dict u pred' loc) - where - (env', pred') = tidyPred env pred +tidyInst :: TidyEnv -> Inst -> Inst +tidyInst env (LitInst u lit ty loc) = LitInst u lit (tidyType env ty) loc +tidyInst env (Dict u pred loc) = Dict u (tidyPred env pred) loc +tidyInst env (Method u id tys theta tau loc) = Method u id (tidyTypes env tys) theta tau loc -tidyInst env (Method u id tys theta tau loc) - = (env', Method u id tys' theta tau loc) - -- Leave theta, tau alone cos we don't print them +tidyMoreInsts :: TidyEnv -> [Inst] -> (TidyEnv, [Inst]) +-- This function doesn't assume that the tyvars are in scope +-- so it works like tidyOpenType, returning a TidyEnv +tidyMoreInsts env insts + = (env', map (tidyInst env') insts) where - (env', tys') = tidyOpenTypes env tys - -tidyInsts env insts = mapAccumL tidyInst env insts + env' = tidyFreeTyVars env (tyVarsOfInsts insts) -show_uniq u = ifPprDebug (text "{-" <> ppr u <> text "-}") +tidyInsts :: [Inst] -> (TidyEnv, [Inst]) +tidyInsts insts = tidyMoreInsts emptyTidyEnv insts \end{code} @@ -578,13 +562,13 @@ lookupInst :: Inst -- Dictionaries -lookupInst dict@(Dict _ (Class clas tys) loc) +lookupInst dict@(Dict _ (ClassP clas tys) loc) = tcGetInstEnv `thenNF_Tc` \ inst_env -> case lookupInstEnv inst_env clas tys of FoundInst tenv dfun_id -> let - (tyvars, rho) = splitForAllTys (idType dfun_id) + (tyvars, rho) = tcSplitForAllTys (idType dfun_id) mk_ty_arg tv = case lookupSubstEnv tenv tv of Just (DoneTy ty) -> returnNF_Tc ty Nothing -> tcInstTyVar tv `thenNF_Tc` \ tc_tv -> @@ -594,7 +578,7 @@ lookupInst dict@(Dict _ (Class clas tys) loc) let subst = mkTyVarSubst tyvars ty_args dfun_rho = substTy subst rho - (theta, _) = splitRhoTy dfun_rho + (theta, _) = tcSplitRhoTy dfun_rho ty_app = mkHsTyApp (HsVar dfun_id) ty_args in if null theta then @@ -618,51 +602,32 @@ lookupInst inst@(Method _ id tys theta _ loc) -- Literals -lookupInst inst@(LitInst u (HsIntegral i) ty loc) - | isIntTy ty && in_int_range -- Short cut for Int - = returnNF_Tc (GenInst [] int_lit) - -- GenInst, not SimpleInst, because int_lit is actually a constructor application - - | isIntegerTy ty -- Short cut for Integer - = returnNF_Tc (GenInst [] integer_lit) +-- Look for short cuts first: if the literal is *definitely* a +-- int, integer, float or a double, generate the real thing here. +-- This is essential (see nofib/spectral/nucleic). +-- [Same shortcut as in newOverloadedLit, but we +-- may have done some unification by now] - | in_int_range -- It's overloaded but small enough to fit into an Int - = -- So we can use the Prelude fromInt - tcLookupSyntaxId fromIntName `thenNF_Tc` \ from_int -> - newMethodAtLoc loc from_int [ty] `thenNF_Tc` \ (method_inst, method_id) -> - returnNF_Tc (GenInst [method_inst] (HsApp (HsVar method_id) int_lit)) +lookupInst inst@(LitInst u lit ty loc) + | Just expr <- shortCutLit lit ty + = returnNF_Tc (GenInst [] expr) -- GenInst, not SimpleInst, because + -- expr may be a constructor application - | otherwise -- Alas, it is overloaded and a big literal! - = tcLookupSyntaxId fromIntegerName `thenNF_Tc` \ from_integer -> +lookupInst inst@(LitInst u (HsIntegral i from_integer_name) ty loc) + = tcLookupId from_integer_name `thenNF_Tc` \ from_integer -> newMethodAtLoc loc from_integer [ty] `thenNF_Tc` \ (method_inst, method_id) -> - returnNF_Tc (GenInst [method_inst] (HsApp (HsVar method_id) integer_lit)) - where - in_int_range = inIntRange i - integer_lit = HsLit (HsInteger i) - int_lit = HsLit (HsInt i) - --- similar idea for overloaded floating point literals: if the literal is --- *definitely* a float or a double, generate the real thing here. --- This is essential (see nofib/spectral/nucleic). + returnNF_Tc (GenInst [method_inst] + (HsApp (HsVar method_id) (HsLit (HsInteger i)))) -lookupInst inst@(LitInst u (HsFractional f) ty loc) - | isFloatTy ty = returnNF_Tc (GenInst [] float_lit) - | isDoubleTy ty = returnNF_Tc (GenInst [] double_lit) - | otherwise - = tcLookupSyntaxId fromRationalName `thenNF_Tc` \ from_rational -> +lookupInst inst@(LitInst u (HsFractional f from_rat_name) ty loc) + = tcLookupId from_rat_name `thenNF_Tc` \ from_rational -> newMethodAtLoc loc from_rational [ty] `thenNF_Tc` \ (method_inst, method_id) -> let - rational_ty = funArgTy (idType method_id) + rational_ty = tcFunArgTy (idType method_id) rational_lit = HsLit (HsRat f rational_ty) in returnNF_Tc (GenInst [method_inst] (HsApp (HsVar method_id) rational_lit)) - - where - floatprim_lit = HsLit (HsFloatPrim f) - float_lit = mkHsConApp floatDataCon [] [floatprim_lit] - doubleprim_lit = HsLit (HsDoublePrim f) - double_lit = mkHsConApp doubleDataCon [] [doubleprim_lit] \end{code} There is a second, simpler interface, when you want an instance of a @@ -672,19 +637,17 @@ ambiguous dictionaries. \begin{code} lookupSimpleInst :: Class - -> [Type] -- Look up (c,t) - -> NF_TcM (Maybe [(Class,[Type])]) -- Here are the needed (c,t)s + -> [Type] -- Look up (c,t) + -> NF_TcM (Maybe ThetaType) -- Here are the needed (c,t)s lookupSimpleInst clas tys = tcGetInstEnv `thenNF_Tc` \ inst_env -> case lookupInstEnv inst_env clas tys of FoundInst tenv dfun - -> returnNF_Tc (Just (substClasses (mkSubst emptyInScopeSet tenv) theta')) + -> returnNF_Tc (Just (substTheta (mkSubst emptyInScopeSet tenv) theta)) where - (_, theta, _) = splitSigmaTy (idType dfun) - theta' = classesOfPreds theta + (_, rho) = tcSplitForAllTys (idType dfun) + (theta,_) = tcSplitRhoTy rho other -> returnNF_Tc Nothing \end{code} - -