diff options
Diffstat (limited to 'compiler/coreSyn/CoreFVs.lhs')
| -rw-r--r-- | compiler/coreSyn/CoreFVs.lhs | 33 |
1 files changed, 19 insertions, 14 deletions
diff --git a/compiler/coreSyn/CoreFVs.lhs b/compiler/coreSyn/CoreFVs.lhs index 2a11723fa9..636c049c42 100644 --- a/compiler/coreSyn/CoreFVs.lhs +++ b/compiler/coreSyn/CoreFVs.lhs @@ -104,8 +104,17 @@ type InterestingVarFun = Var -> Bool \begin{code} type FV = InterestingVarFun - -> VarSet -- In scope + -> VarSet -- Locally bound -> VarSet -- Free vars + -- Return the vars that are both (a) interesting + -- and (b) not locally bound + -- See function keep_it + +keep_it :: InterestingVarFun -> VarSet -> Var -> Bool +keep_it fv_cand in_scope var + | var `elemVarSet` in_scope = False + | fv_cand var = True + | otherwise = False union :: FV -> FV -> FV union fv1 fv2 fv_cand in_scope = fv1 fv_cand in_scope `unionVarSet` fv2 fv_cand in_scope @@ -152,13 +161,6 @@ someVars :: VarSet -> FV someVars vars fv_cand in_scope = filterVarSet (keep_it fv_cand in_scope) vars -keep_it :: InterestingVarFun -> VarSet -> Var -> Bool -keep_it fv_cand in_scope var - | var `elemVarSet` in_scope = False - | fv_cand var = True - | otherwise = False - - addBndr :: CoreBndr -> FV -> FV addBndr bndr fv fv_cand in_scope = someVars (varTypeTyVars bndr) fv_cand in_scope @@ -434,15 +436,18 @@ idUnfoldingVars :: Id -> VarSet -- and we'll get exponential behaviour if we look at both unf and rhs! -- But do look at the *real* unfolding, even for loop breakers, else -- we might get out-of-scope variables -idUnfoldingVars id = stableUnfoldingVars isLocalId (realIdUnfolding id) `orElse` emptyVarSet +idUnfoldingVars id = stableUnfoldingVars (realIdUnfolding id) `orElse` emptyVarSet -stableUnfoldingVars :: InterestingVarFun -> Unfolding -> Maybe VarSet -stableUnfoldingVars fv_cand unf +stableUnfoldingVars :: Unfolding -> Maybe VarSet +stableUnfoldingVars unf = case unf of CoreUnfolding { uf_tmpl = rhs, uf_src = src } - | isStableSource src -> Just (exprSomeFreeVars fv_cand rhs) - DFunUnfolding _ _ args -> Just (exprsSomeFreeVars fv_cand (dfunArgExprs args)) - _other -> Nothing + | isStableSource src + -> Just (exprFreeVars rhs) + DFunUnfolding { df_bndrs = bndrs, df_args = args } + -> Just (exprs_fvs args isLocalVar (mkVarSet bndrs)) + -- DFuns are top level, so no fvs from types of bndrs + _other -> Nothing \end{code} |