Equality constraint solver is now externally pure

[ghc-hetmet.git] / compiler / coreSyn / CoreFVs.lhs

diff --git a/compiler/coreSyn/CoreFVs.lhs b/compiler/coreSyn/CoreFVs.lhs
index dedc4c0..e2eb3a2 100644 (file)
--- a/compiler/coreSyn/CoreFVs.lhs
+++ b/compiler/coreSyn/CoreFVs.lhs
@@ -25,7 +25,7 @@ module CoreFVs (
        exprFreeNames, exprsFreeNames,
 
         -- * Free variables of Rules, Vars and Ids
-       idRuleVars, idFreeVars, varTypeTyVars, 
+       idRuleVars, idFreeVars, varTypeTyVars, varTypeTcTyVars, 
        ruleRhsFreeVars, rulesFreeVars,
        ruleLhsFreeNames, ruleLhsFreeIds, 
 
@@ -194,7 +194,7 @@ expr_fvs (Let (Rec pairs) body)
 
 ---------
 rhs_fvs :: (Id,CoreExpr) -> FV
-rhs_fvs (bndr, rhs) = expr_fvs rhs `union` someVars (idRuleVars bndr)
+rhs_fvs (bndr, rhs) = expr_fvs rhs `union` someVars (bndrRuleVars bndr)
        -- Treat any RULES as extra RHSs of the binding
 
 ---------
@@ -370,9 +370,20 @@ varTypeTyVars var
   | isLocalId var || isCoVar var = tyVarsOfType (idType var)
   | otherwise = emptyVarSet    -- Global Ids and non-coercion TyVars
 
+varTypeTcTyVars :: Var -> TyVarSet
+-- Find the type variables free in the type of the variable
+-- Remember, coercion variables can mention type variables...
+varTypeTcTyVars var
+  | isLocalId var || isCoVar var = tcTyVarsOfType (idType var)
+  | otherwise = emptyVarSet    -- Global Ids and non-coercion TyVars
+
 idFreeVars :: Id -> VarSet
 idFreeVars id = ASSERT( isId id) idRuleVars id `unionVarSet` varTypeTyVars id
 
+bndrRuleVars ::Var -> VarSet
+bndrRuleVars v | isTyVar v = emptyVarSet
+              | otherwise = idRuleVars v
+
 idRuleVars ::Id -> VarSet
 idRuleVars id = ASSERT( isId id) specInfoFreeVars (idSpecialisation id)
 \end{code}
@@ -425,7 +436,7 @@ freeVars (Case scrut bndr ty alts)
                             rhs2 = freeVars rhs
 
 freeVars (Let (NonRec binder rhs) body)
-  = (freeVarsOf rhs2 `unionFVs` body_fvs `unionFVs` idRuleVars binder,
+  = (freeVarsOf rhs2 `unionFVs` body_fvs `unionFVs` bndrRuleVars binder,
                -- Remember any rules; cf rhs_fvs above
      AnnLet (AnnNonRec binder rhs2) body2)
   where