-- The above warning supression flag is a temporary kludge.
-- While working on this module you are encouraged to remove it and fix
-- any warnings in the module. See
--- http://hackage.haskell.org/trac/ghc/wiki/CodingStyle#Warnings
+-- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
-- for details
module IdInfo (
-- Specialisation
SpecInfo(..), specInfo, setSpecInfo, isEmptySpecInfo,
- specInfoFreeVars, specInfoRules, seqSpecInfo,
+ specInfoFreeVars, specInfoRules, seqSpecInfo, setSpecInfoHead,
-- CAF info
CafInfo(..), cafInfo, ppCafInfo, setCafInfo, mayHaveCafRefs,
import CoreSyn
import Class
import PrimOp
+import Name
import Var
import VarSet
import BasicTypes
import Data.Maybe
#ifdef OLD_STRICTNESS
-import Name
import Demand
import qualified Demand
import Util
data SpecInfo
= SpecInfo
[CoreRule]
- VarSet -- Locally-defined free vars of *both* LHS and RHS of rules
- -- Note [Rule dependency info]
+ VarSet -- Locally-defined free vars of *both* LHS and RHS
+ -- of rules. I don't think it needs to include the
+ -- ru_fn though.
+ -- Note [Rule dependency info] in OccurAnal
emptySpecInfo :: SpecInfo
emptySpecInfo = SpecInfo [] emptyVarSet
specInfoRules :: SpecInfo -> [CoreRule]
specInfoRules (SpecInfo rules _) = rules
+setSpecInfoHead :: Name -> SpecInfo -> SpecInfo
+setSpecInfoHead fn (SpecInfo rules fvs)
+ = SpecInfo (map set_head rules) fvs
+ where
+ set_head rule = rule { ru_fn = fn }
+
seqSpecInfo (SpecInfo rules fvs) = seqRules rules `seq` seqVarSet fvs
\end{code}
-Note [Rule dependency info]
-~~~~~~~~~~~~~~~~~~~~~~~~~~~
-THe VarSet in a SpecInfo is used for dependency analysis in the
-occurrence analyser. We must track free vars in *both* lhs and rhs. Why both?
-Consider
- x = y
- RULE f x = 4
-Then if we substitute y for x, we'd better do so in the
- rule's LHS too, so we'd better ensure the dependency is respsected
-
%************************************************************************
-- The "unsafe" occ info is the ones that say I'm not in a lambda
-- because that might not be true for an unsaturated lambda
is_safe_occ (OneOcc in_lam _ _) = in_lam
- is_safe_occ other = True
+ is_safe_occ _other = True
safe_occ = case occ of
OneOcc _ once int_cxt -> OneOcc insideLam once int_cxt
- other -> occ
+ _other -> occ
is_safe_dmd Nothing = True
is_safe_dmd (Just dmd) = not (isStrictDmd dmd)
\begin{code}
zapFragileInfo :: IdInfo -> Maybe IdInfo
-- Zap info that depends on free variables
-zapFragileInfo info = Just (info `setSpecInfo` emptySpecInfo
- `setWorkerInfo` NoWorker
- `setUnfoldingInfo` NoUnfolding)
+zapFragileInfo info
+ = Just (info `setSpecInfo` emptySpecInfo
+ `setWorkerInfo` NoWorker
+ `setUnfoldingInfo` NoUnfolding
+ `setOccInfo` if isFragileOcc occ then NoOccInfo else occ)
+ where
+ occ = occInfo info
\end{code}
%************************************************************************