\begin{code}
module Rules (
- RuleBase, prepareRuleBase, lookupRule, addRule,
- addIdSpecialisations,
+ RuleBase, prepareLocalRuleBase, prepareOrphanRuleBase,
+ unionRuleBase, lookupRule, addRule, addIdSpecialisations,
ProtoCoreRule(..), pprProtoCoreRule,
- orphanRule
+ localRule, orphanRule
) where
#include "HsVersions.h"
= case idSpecialisation fn of
Rules rules _ -> matchRules in_scope rules args
+localRule :: ProtoCoreRule -> Bool
+localRule (ProtoCoreRule local _ _) = local
+
orphanRule :: ProtoCoreRule -> Bool
-- An "orphan rule" is one that is defined in this
-- module, but for an *imported* function. We need
IdSet) -- Ids (whether local or imported) mentioned on
-- LHS of some rule; these should be black listed
+unionRuleBase (rule_ids1, black_ids1) (rule_ids2, black_ids2)
+ = (plusUFM_C merge_rules rule_ids1 rule_ids2,
+ unionVarSet black_ids1 black_ids2)
+ where
+ merge_rules id1 id2 = let rules1 = idSpecialisation id1
+ rules2 = idSpecialisation id2
+ new_rules = foldl (addRule id1) rules1 (rulesRules rules2)
+ in
+ setIdSpecialisation id1 new_rules
+
+-- prepareLocalRuleBase takes the CoreBinds and rules defined in this module.
+-- It attaches those rules that are for local Ids to their binders, and
+-- returns the remainder attached to Ids in an IdSet. It also returns
+-- Ids mentioned on LHS of some rule; these should be blacklisted.
+
-- The rule Ids and LHS Ids are black-listed; that is, they aren't inlined
-- so that the opportunity to apply the rule isn't lost too soon
-prepareRuleBase :: [CoreBind] -> [ProtoCoreRule] -> ([CoreBind], RuleBase)
-prepareRuleBase binds all_rules
- = (map zap_bind binds, (imported_rule_ids, rule_lhs_fvs))
+prepareLocalRuleBase :: [CoreBind] -> [ProtoCoreRule] -> ([CoreBind], RuleBase)
+prepareLocalRuleBase binds local_rules
+ = (map zap_bind binds, (imported_id_rule_ids, rule_lhs_fvs))
where
- (rule_ids, rule_lhs_fvs) = foldr add_rule (emptyVarSet, emptyVarSet) all_rules
- imported_rule_ids = filterVarSet (not . isLocallyDefined) rule_ids
+ (rule_ids, rule_lhs_fvs) = foldr add_rule (emptyVarSet, emptyVarSet) local_rules
+ imported_id_rule_ids = filterVarSet (not . isLocallyDefined) rule_ids
- -- rule_fvs is the set of all variables mentioned in rules
+ -- rule_fvs is the set of all variables mentioned in this module's rules
rule_fvs = foldVarSet (unionVarSet . idRuleVars) rule_lhs_fvs rule_ids
-- Attach the rules for each locally-defined Id to that Id.
-- locally defined ones!!
addRuleToId id rule = setIdSpecialisation id (addRule id (idSpecialisation id) rule)
+
+-- prepareOrphanRuleBase does exactly the same as prepareLocalRuleBase, except that
+-- it assumes that none of the rules can be attached to local Ids.
+
+prepareOrphanRuleBase :: [ProtoCoreRule] -> RuleBase
+prepareOrphanRuleBase imported_rules
+ = foldr add_rule (emptyVarSet, emptyVarSet) imported_rules
\end{code}