+
+module Vectorise.Type.Classify
+ ( TyConGroup
+ , classifyTyCons
+ , tyConGroups)
+where
+import UniqSet
+import UniqFM
+import DataCon
+import TyCon
+import TypeRep
+import Type
+import Digraph
+import Outputable
+
+type TyConGroup = ([TyCon], UniqSet TyCon)
+
+-- | Split the given tycons into two sets depending on whether they have to be
+-- converted (first list) or not (second list). The first argument contains
+-- information about the conversion status of external tycons:
+--
+-- * tycons which have converted versions are mapped to True
+-- * tycons which are not changed by vectorisation are mapped to False
+-- * tycons which can't be converted are not elements of the map
+--
+classifyTyCons
+ :: UniqFM Bool
+ -> [TyConGroup]
+ -> ([TyCon], [TyCon])
+
+classifyTyCons = classify [] []
+ where
+ classify conv keep _ [] = (conv, keep)
+ classify conv keep cs ((tcs, ds) : rs)
+ | can_convert && must_convert
+ = classify (tcs ++ conv) keep (cs `addListToUFM` [(tc,True) | tc <- tcs]) rs
+ | can_convert
+ = classify conv (tcs ++ keep) (cs `addListToUFM` [(tc,False) | tc <- tcs]) rs
+ | otherwise
+ = classify conv keep cs rs
+ where
+ refs = ds `delListFromUniqSet` tcs
+
+ can_convert = isNullUFM (refs `minusUFM` cs) && all convertable tcs
+ must_convert = foldUFM (||) False (intersectUFM_C const cs refs)
+
+ convertable tc = isDataTyCon tc && all isVanillaDataCon (tyConDataCons tc)
+
+
+-- | Compute mutually recursive groups of tycons in topological order
+tyConGroups :: [TyCon] -> [TyConGroup]
+tyConGroups tcs = map mk_grp (stronglyConnCompFromEdgedVertices edges)
+ where
+ edges = [((tc, ds), tc, uniqSetToList ds) | tc <- tcs
+ , let ds = tyConsOfTyCon tc]
+
+ mk_grp (AcyclicSCC (tc, ds)) = ([tc], ds)
+ mk_grp (CyclicSCC els) = (tcs, unionManyUniqSets dss)
+ where
+ (tcs, dss) = unzip els
+
+
+-- | Collect the set of TyCons used by the representation of some data type.
+tyConsOfTyCon :: TyCon -> UniqSet TyCon
+tyConsOfTyCon
+ = tyConsOfTypes . concatMap dataConRepArgTys . tyConDataCons
+
+
+-- | Collect the set of TyCons that occur in these types.
+tyConsOfTypes :: [Type] -> UniqSet TyCon
+tyConsOfTypes = unionManyUniqSets . map tyConsOfType
+
+
+-- | Collect the set of TyCons that occur in this type.
+tyConsOfType :: Type -> UniqSet TyCon
+tyConsOfType ty
+ | Just ty' <- coreView ty = tyConsOfType ty'
+tyConsOfType (TyVarTy _) = emptyUniqSet
+tyConsOfType (TyConApp tc tys) = extend (tyConsOfTypes tys)
+ where
+ extend | isUnLiftedTyCon tc
+ || isTupleTyCon tc = id
+
+ | otherwise = (`addOneToUniqSet` tc)
+
+tyConsOfType (AppTy a b) = tyConsOfType a `unionUniqSets` tyConsOfType b
+tyConsOfType (FunTy a b) = (tyConsOfType a `unionUniqSets` tyConsOfType b)
+ `addOneToUniqSet` funTyCon
+tyConsOfType (ForAllTy _ ty) = tyConsOfType ty
+tyConsOfType other = pprPanic "ClosureConv.tyConsOfType" $ ppr other
+