projects
/
ghc-hetmet.git
/ blobdiff
commit
grep
author
committer
pickaxe
?
search:
re
summary
|
shortlog
|
log
|
commit
|
commitdiff
|
tree
raw
|
inline
| side by side
Fix warning about multiply exported name
[ghc-hetmet.git]
/
compiler
/
types
/
Coercion.lhs
diff --git
a/compiler/types/Coercion.lhs
b/compiler/types/Coercion.lhs
index
bc93372
..
794613b
100644
(file)
--- a/
compiler/types/Coercion.lhs
+++ b/
compiler/types/Coercion.lhs
@@
-379,9
+379,18
@@
mkInstsCoercion co tys = foldl mkInstCoercion co tys
-- | Manufacture a coercion from this air. Needless to say, this is not usually safe,
-- but it is used when we know we are dealing with bottom, which is one case in which
-- it is safe. This is also used implement the @unsafeCoerce#@ primitive.
-- | Manufacture a coercion from this air. Needless to say, this is not usually safe,
-- but it is used when we know we are dealing with bottom, which is one case in which
-- it is safe. This is also used implement the @unsafeCoerce#@ primitive.
+-- Optimise by pushing down through type constructors
mkUnsafeCoercion :: Type -> Type -> Coercion
mkUnsafeCoercion :: Type -> Type -> Coercion
-mkUnsafeCoercion ty1 ty2 = mkCoercion unsafeCoercionTyCon [ty1, ty2]
+mkUnsafeCoercion (TyConApp tc1 tys1) (TyConApp tc2 tys2)
+ | tc1 == tc2
+ = TyConApp tc1 (zipWith mkUnsafeCoercion tys1 tys2)
+mkUnsafeCoercion (FunTy a1 r1) (FunTy a2 r2)
+ = FunTy (mkUnsafeCoercion a1 a2) (mkUnsafeCoercion r1 r2)
+
+mkUnsafeCoercion ty1 ty2
+ | ty1 `coreEqType` ty2 = ty1
+ | otherwise = mkCoercion unsafeCoercionTyCon [ty1, ty2]
-- See note [Newtype coercions] in TyCon
-- See note [Newtype coercions] in TyCon
@@
-629,7
+638,7
@@
mkAppTyCoI ty1 coi1 ty2 coi2 =
mkFunTyCoI :: Type -> CoercionI -> Type -> CoercionI -> CoercionI
mkFunTyCoI _ IdCo _ IdCo = IdCo
mkFunTyCoI ty1 coi1 ty2 coi2 =
mkFunTyCoI :: Type -> CoercionI -> Type -> CoercionI -> CoercionI
mkFunTyCoI _ IdCo _ IdCo = IdCo
mkFunTyCoI ty1 coi1 ty2 coi2 =
- ACo $ FunTy (fromCoI coi1 ty1) (fromCoI coi2 ty2)
+ ACo $ mkFunTy (fromCoI coi1 ty1) (fromCoI coi2 ty2)
-- | Smart constructor for quantified 'Coercion's on 'CoercionI', see also 'mkForAllCoercion'
mkForAllTyCoI :: TyVar -> CoercionI -> CoercionI
-- | Smart constructor for quantified 'Coercion's on 'CoercionI', see also 'mkForAllCoercion'
mkForAllTyCoI :: TyVar -> CoercionI -> CoercionI