diff options
Diffstat (limited to 'compiler/coreSyn/CoreSubst.hs')
| -rw-r--r-- | compiler/coreSyn/CoreSubst.hs | 47 |
1 files changed, 21 insertions, 26 deletions
diff --git a/compiler/coreSyn/CoreSubst.hs b/compiler/coreSyn/CoreSubst.hs index 167654e1ea..a31650969e 100644 --- a/compiler/coreSyn/CoreSubst.hs +++ b/compiler/coreSyn/CoreSubst.hs @@ -21,7 +21,7 @@ module CoreSubst ( -- ** Operations on substitutions emptySubst, mkEmptySubst, mkSubst, mkOpenSubst, substInScope, isEmptySubst, - extendIdSubst, extendIdSubstList, extendTCvSubst, extendTCvSubstList, + extendIdSubst, extendIdSubstList, extendTCvSubst, extendTvSubstList, extendSubst, extendSubstList, extendSubstWithVar, zapSubstEnv, addInScopeSet, extendInScope, extendInScopeList, extendInScopeIds, isInScope, setInScope, @@ -50,7 +50,7 @@ import qualified Type import qualified Coercion -- We are defining local versions -import Type hiding ( substTy, extendTCvSubst, extendTCvSubstList +import Type hiding ( substTy, extendTvSubst, extendCvSubst, extendTvSubstList , isInScope, substTyVarBndr, cloneTyVarBndr ) import Coercion hiding ( substCo, substCoVarBndr ) @@ -215,48 +215,43 @@ extendIdSubst (Subst in_scope ids tvs cvs) v r = Subst in_scope (extendVarEnv id extendIdSubstList :: Subst -> [(Id, CoreExpr)] -> Subst extendIdSubstList (Subst in_scope ids tvs cvs) prs = Subst in_scope (extendVarEnvList ids prs) tvs cvs --- | Add a substitution for a 'TyVar' to the 'Subst': the 'TyVar' *must* --- be a real TyVar, and not a CoVar -extend_tv_subst :: Subst -> TyVar -> Type -> Subst -extend_tv_subst (Subst in_scope ids tvs cvs) tv ty +-- | Add a substitution for a 'TyVar' to the 'Subst' +-- The 'TyVar' *must* be a real TyVar, and not a CoVar +-- You must ensure that the in-scope set is such that +-- the "CoreSubst#in_scope_invariant" is true after extending +-- the substitution like this. +extendTvSubst :: Subst -> TyVar -> Type -> Subst +extendTvSubst (Subst in_scope ids tvs cvs) tv ty = ASSERT( isTyVar tv ) Subst in_scope ids (extendVarEnv tvs tv ty) cvs --- | Add a substitution for a 'TyVar' to the 'Subst': you must ensure that the in-scope set is --- such that the "CoreSubst#in_scope_invariant" is true after extending the substitution like this -extendTCvSubst :: Subst -> TyVar -> Type -> Subst -extendTCvSubst subst v r - | isTyVar v - = extend_tv_subst subst v r - | Just co <- isCoercionTy_maybe r - = extendCvSubst subst v co - | otherwise - = pprPanic "CoreSubst.extendTCvSubst" (ppr v <+> text "|->" <+> ppr r) - --- | Adds multiple 'TyVar' substitutions to the 'Subst': see also 'extendTCvSubst' -extendTCvSubstList :: Subst -> [(TyVar,Type)] -> Subst -extendTCvSubstList subst vrs +-- | Adds multiple 'TyVar' substitutions to the 'Subst': see also 'extendTvSubst' +extendTvSubstList :: Subst -> [(TyVar,Type)] -> Subst +extendTvSubstList subst vrs = foldl' extend subst vrs - where extend subst (v, r) = extendTCvSubst subst v r + where + extend subst (v, r) = extendTvSubst subst v r -- | Add a substitution from a 'CoVar' to a 'Coercion' to the 'Subst': you must ensure that the in-scope set is -- such that the "CoreSubst#in_scope_invariant" is true after extending the substitution like this extendCvSubst :: Subst -> CoVar -> Coercion -> Subst -extendCvSubst (Subst in_scope ids tvs cvs) v r = Subst in_scope ids tvs (extendVarEnv cvs v r) +extendCvSubst (Subst in_scope ids tvs cvs) v r + = ASSERT( isCoVar v ) + Subst in_scope ids tvs (extendVarEnv cvs v r) -- | Add a substitution appropriate to the thing being substituted -- (whether an expression, type, or coercion). See also --- 'extendIdSubst', 'extendTCvSubst' +-- 'extendIdSubst', 'extendTvSubst', 'extendCvSubst' extendSubst :: Subst -> Var -> CoreArg -> Subst extendSubst subst var arg = case arg of - Type ty -> ASSERT( isTyVar var ) extend_tv_subst subst var ty + Type ty -> ASSERT( isTyVar var ) extendTvSubst subst var ty Coercion co -> ASSERT( isCoVar var ) extendCvSubst subst var co _ -> ASSERT( isId var ) extendIdSubst subst var arg extendSubstWithVar :: Subst -> Var -> Var -> Subst extendSubstWithVar subst v1 v2 - | isTyVar v1 = ASSERT( isTyVar v2 ) extend_tv_subst subst v1 (mkTyVarTy v2) + | isTyVar v1 = ASSERT( isTyVar v2 ) extendTvSubst subst v1 (mkTyVarTy v2) | isCoVar v1 = ASSERT( isCoVar v2 ) extendCvSubst subst v1 (mkCoVarCo v2) | otherwise = ASSERT( isId v2 ) extendIdSubst subst v1 (Var v2) @@ -1050,7 +1045,7 @@ maybe_substitute :: Subst -> InVar -> OutExpr -> Maybe Subst maybe_substitute subst b r | Type ty <- r -- let a::* = TYPE ty in <body> = ASSERT( isTyVar b ) - Just (extendTCvSubst subst b ty) + Just (extendTvSubst subst b ty) | Coercion co <- r = ASSERT( isCoVar b ) |