+mkClosure :: Type -> Type -> Type -> VExpr -> VExpr -> VM VExpr
+mkClosure arg_ty res_ty env_ty (vfn,lfn) (venv,lenv)
+ = do
+ dict <- paDictOfType env_ty
+ mkv <- builtin mkClosureVar
+ mkl <- builtin mkClosurePVar
+ return (Var mkv `mkTyApps` [arg_ty, res_ty, env_ty] `mkApps` [dict, vfn, lfn, venv],
+ Var mkl `mkTyApps` [arg_ty, res_ty, env_ty] `mkApps` [dict, vfn, lfn, lenv])
+
+mkClosureApp :: VExpr -> VExpr -> VM VExpr
+mkClosureApp (vclo, lclo) (varg, larg)
+ = do
+ vapply <- builtin applyClosureVar
+ lapply <- builtin applyClosurePVar
+ return (Var vapply `mkTyApps` [arg_ty, res_ty] `mkApps` [vclo, varg],
+ Var lapply `mkTyApps` [arg_ty, res_ty] `mkApps` [lclo, larg])
+ where
+ (arg_ty, res_ty) = splitClosureTy (exprType vclo)
+
+buildClosures :: [TyVar] -> Var -> [VVar] -> [Type] -> Type -> VM VExpr -> VM VExpr
+buildClosures tvs lc vars [arg_ty] res_ty mk_body
+ = buildClosure tvs lc vars arg_ty res_ty mk_body
+buildClosures tvs lc vars (arg_ty : arg_tys) res_ty mk_body
+ = do
+ res_ty' <- mkClosureTypes arg_tys res_ty
+ arg <- newLocalVVar FSLIT("x") arg_ty
+ buildClosure tvs lc vars arg_ty res_ty'
+ . hoistPolyVExpr tvs
+ $ do
+ clo <- buildClosures tvs lc (vars ++ [arg]) arg_tys res_ty mk_body
+ return $ vLams lc (vars ++ [arg]) clo
+
+-- (clo <x1,...,xn> <f,f^>, aclo (Arr lc xs1 ... xsn) <f,f^>)
+-- where
+-- f = \env v -> case env of <x1,...,xn> -> e x1 ... xn v
+-- f^ = \env v -> case env of Arr l xs1 ... xsn -> e^ l x1 ... xn v
+--
+buildClosure :: [TyVar] -> Var -> [VVar] -> Type -> Type -> VM VExpr -> VM VExpr
+buildClosure tvs lv vars arg_ty res_ty mk_body
+ = do
+ (env_ty, env, bind) <- buildEnv lv vars
+ env_bndr <- newLocalVVar FSLIT("env") env_ty
+ arg_bndr <- newLocalVVar FSLIT("arg") arg_ty
+
+ fn <- hoistPolyVExpr tvs
+ $ do
+ body <- mk_body
+ body' <- bind (vVar env_bndr)
+ (vVarApps lv body (vars ++ [arg_bndr]))
+ return (vLamsWithoutLC [env_bndr, arg_bndr] body')
+
+ mkClosure arg_ty res_ty env_ty fn env
+
+buildEnv :: Var -> [VVar] -> VM (Type, VExpr, VExpr -> VExpr -> VM VExpr)
+buildEnv lv vvs
+ = do
+ let (ty, venv, vbind) = mkVectEnv tys vs
+ (lenv, lbind) <- mkLiftEnv lv tys ls
+ return (ty, (venv, lenv),
+ \(venv,lenv) (vbody,lbody) ->
+ do
+ let vbody' = vbind venv vbody
+ lbody' <- lbind lenv lbody
+ return (vbody', lbody'))
+ where
+ (vs,ls) = unzip vvs
+ tys = map idType vs
+
+mkVectEnv :: [Type] -> [Var] -> (Type, CoreExpr, CoreExpr -> CoreExpr -> CoreExpr)
+mkVectEnv [] [] = (unitTy, Var unitDataConId, \env body -> body)
+mkVectEnv [ty] [v] = (ty, Var v, \env body -> Let (NonRec v env) body)
+mkVectEnv tys vs = (ty, mkCoreTup (map Var vs),
+ \env body -> Case env (mkWildId ty) (exprType body)
+ [(DataAlt (tupleCon Boxed (length vs)), vs, body)])
+ where
+ ty = mkCoreTupTy tys
+
+mkLiftEnv :: Var -> [Type] -> [Var] -> VM (CoreExpr, CoreExpr -> CoreExpr -> VM CoreExpr)
+mkLiftEnv lv [ty] [v]
+ = return (Var v, \env body ->
+ do
+ len <- lengthPA (Var v)
+ return . Let (NonRec v env)
+ $ Case len lv (exprType body) [(DEFAULT, [], body)])
+
+-- NOTE: this transparently deals with empty environments
+mkLiftEnv lv tys vs
+ = do
+ (env_tc, env_tyargs) <- lookupPArrayFamInst vty
+ let [env_con] = tyConDataCons env_tc
+
+ env = Var (dataConWrapId env_con)
+ `mkTyApps` env_tyargs
+ `mkVarApps` (lv : vs)
+
+ bind env body = let scrut = unwrapFamInstScrut env_tc env_tyargs env
+ in
+ return $ Case scrut (mkWildId (exprType scrut))
+ (exprType body)
+ [(DataAlt env_con, lv : bndrs, body)]
+ return (env, bind)
+ where
+ vty = mkCoreTupTy tys
+
+ bndrs | null vs = [mkWildId unitTy]
+ | otherwise = vs
+