HsBindGroup(..), LRuleDecl, HsBind(..) )
import TcRnTypes ( TcGblEnv(..), ImportAvails(..) )
import MkIface ( mkUsageInfo )
-import Id ( Id, setIdExported, idName, idIsFrom )
-import Name ( Name, isExternalName )
+import Id ( Id, setIdExported, idName )
+import Name ( Name, isExternalName, nameIsLocalOrFrom, nameOccName )
import CoreSyn
-import PprCore ( pprIdRules, pprCoreExpr )
+import PprCore ( pprRules, pprCoreExpr )
import CoreSubst ( substExpr, mkSubst )
import DsMonad
import DsExpr ( dsLExpr )
import VarEnv
import VarSet
import Bag ( Bag, isEmptyBag, emptyBag, bagToList )
+import Rules ( roughTopNames )
import CoreLint ( showPass, endPass )
-import CoreFVs ( ruleRhsFreeVars )
+import CoreFVs ( ruleRhsFreeVars, exprsFreeNames )
import Packages ( PackageState(thPackageId), PackageIdH(..) )
import ErrUtils ( doIfSet, dumpIfSet_dyn, pprBagOfWarnings,
errorsFound, WarnMsg )
| otherwise = bndr
orph_rhs_fvs = unionVarSets [ ruleRhsFreeVars rule
- | IdCoreRule _ is_orphan_rule rule <- rules,
- is_orphan_rule ]
- -- An orphan rule keeps alive the free vars of its right-hand side.
- -- Non-orphan rules are (later, after gentle simplification)
- -- attached to the Id and that keeps the rhs free vars alive
+ | rule <- rules,
+ not (isLocalRule rule) ]
+ -- A non-local rule keeps alive the free vars of its right-hand side.
+ -- (A "non-local" is one whose head function is not locally defined.)
+ -- Local rules are (later, after gentle simplification)
+ -- attached to the Id, and that keeps the rhs free vars alive.
dont_discard bndr = is_exported name
|| name `elemNameSet` keep_alive
ppr_ds_rules [] = empty
ppr_ds_rules rules
= text "" $$ text "-------------- DESUGARED RULES -----------------" $$
- pprIdRules rules
+ pprRules rules
\end{code}
%************************************************************************
\begin{code}
-dsRule :: Module -> IdSet -> LRuleDecl Id -> DsM IdCoreRule
+dsRule :: Module -> IdSet -> LRuleDecl Id -> DsM CoreRule
dsRule mod in_scope (L loc (HsRule name act vars lhs rhs))
= putSrcSpanDs loc $
- ds_lhs all_vars lhs `thenDs` \ (fn, args) ->
- dsLExpr rhs `thenDs` \ core_rhs ->
- returnDs (IdCoreRule fn (is_orphan fn) (Rule name act tpl_vars args core_rhs))
- where
- tpl_vars = [var | RuleBndr (L _ var) <- vars]
- all_vars = mkInScopeSet (extendVarSetList in_scope tpl_vars)
- is_orphan id = not (idIsFrom mod id)
- -- NB we can't use isLocalId in the orphan test,
- -- because isLocalId isn't true of class methods
-
-ds_lhs all_vars lhs
- = let
- (dict_binds, body) =
- case unLoc lhs of
- (HsLet [HsBindGroup dict_binds _ _] body) -> (dict_binds, body)
- other -> (emptyBag, lhs)
- in
- mappM ds_dict_bind (bagToList dict_binds) `thenDs` \ dict_binds' ->
- dsLExpr body `thenDs` \ body' ->
+ do { let (dict_binds, body)
+ = case unLoc lhs of
+ (HsLet [HsBindGroup dbs _ _] body) -> (dbs, body)
+ other -> (emptyBag, lhs)
+
+ ds_dict_bind (L _ (VarBind id rhs))
+ = do { rhs' <- dsLExpr rhs ; returnDs (id,rhs') }
+
+ ; dict_binds' <- mappM ds_dict_bind (bagToList dict_binds)
+ ; body' <- dsLExpr body
+ ; rhs' <- dsLExpr rhs
-- Substitute the dict bindings eagerly,
-- and take the body apart into a (f args) form
- let
- subst = mkSubst all_vars emptyVarEnv (mkVarEnv id_pairs)
- id_pairs = [(id, substExpr subst rhs) | (id,rhs) <- dict_binds']
+ ; let bndrs = [var | RuleBndr (L _ var) <- vars]
+ in_scope' = mkInScopeSet (extendVarSetList in_scope bndrs)
+ subst = mkSubst in_scope' emptyVarEnv (mkVarEnv id_pairs)
+ id_pairs = [(id, substExpr subst rhs) | (id,rhs) <- dict_binds']
-- Note recursion here... substitution won't terminate
-- if there is genuine recursion... which there isn't
- body'' = substExpr subst body'
- in
-
- -- Now unpack the resulting body
- let
- pair = case collectArgs body'' of
- (Var fn, args) -> (fn, args)
- other -> pprPanic "dsRule" (ppr lhs)
- in
- returnDs pair
-
-ds_dict_bind (L _ (VarBind id rhs)) =
- dsLExpr rhs `thenDs` \ rhs' ->
- returnDs (id,rhs')
+ body'' = substExpr subst body'
+
+ (fn, args) = case collectArgs body'' of
+ (Var fn_id, args) -> (idName fn_id, args)
+ other -> pprPanic "dsRule" (ppr lhs)
+
+ local_rule = nameIsLocalOrFrom mod fn
+ -- NB we can't use isLocalId in the orphan test,
+ -- because isLocalId isn't true of class methods
+ lhs_names = fn : nameSetToList (exprsFreeNames args)
+ -- No need to delete bndrs, because
+ -- exprsFreeNams finds only External names
+ orph = case filter (nameIsLocalOrFrom mod) lhs_names of
+ (n:ns) -> Just (nameOccName n)
+ [] -> Nothing
+
+ ; return (Rule { ru_name = name, ru_fn = fn, ru_act = act,
+ ru_bndrs = bndrs, ru_args = args, ru_rhs = rhs',
+ ru_rough = roughTopNames args,
+ ru_local = local_rule, ru_orph = orph })
+ }
\end{code}
projects / ghc-hetmet.git / blobdiff