diff options
Diffstat (limited to 'compiler/GHC/Core/Opt/Simplify.hs')
| -rw-r--r-- | compiler/GHC/Core/Opt/Simplify.hs | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/compiler/GHC/Core/Opt/Simplify.hs b/compiler/GHC/Core/Opt/Simplify.hs index b799c1df59..be8b72ace4 100644 --- a/compiler/GHC/Core/Opt/Simplify.hs +++ b/compiler/GHC/Core/Opt/Simplify.hs @@ -425,10 +425,10 @@ simplNonRecX env bndr new_rhs ; completeNonRecX NotTopLevel env' (isStrictId bndr') bndr bndr' new_rhs } -- NotTopLevel: simplNonRecX is only used for NotTopLevel things -- - -- isStrictId: use bndr' because in a levity-polymorphic setting - -- the InId bndr might have a levity-polymorphic type, which - -- which isStrictId doesn't expect - -- c.f. Note [Dark corner with levity polymorphism] + -- isStrictId: use bndr' because in a representation-polymorphic + -- setting, the InId bndr might have a representation-polymorphic + -- type, which isStrictId doesn't expect + -- c.f. Note [Dark corner with representation polymorphism] -------------------------- completeNonRecX :: TopLevelFlag -> SimplEnv @@ -1484,7 +1484,7 @@ simplCast env body co0 cont0 levity_ok MRefl = True levity_ok (MCo co) = not $ isTypeLevPoly $ coercionRKind co -- Without this check, we get a lev-poly arg - -- See Note [Levity polymorphism invariants] in GHC.Core + -- See Note [Representation polymorphism invariants] in GHC.Core -- test: typecheck/should_run/EtaExpandLevPoly simplArg :: SimplEnv -> DupFlag -> StaticEnv -> CoreExpr @@ -1593,7 +1593,7 @@ simplNonRecE env bndr (rhs, rhs_se) (bndrs, body) cont = do { (env1, bndr1) <- simplNonRecBndr env bndr -- Deal with strict bindings - -- See Note [Dark corner with levity polymorphism] + -- See Note [Dark corner with representation polymorphism] ; if isStrictId bndr1 && sm_case_case (getMode env) then simplExprF (rhs_se `setInScopeFromE` env) rhs (StrictBind { sc_bndr = bndr, sc_bndrs = bndrs, sc_body = body @@ -1625,17 +1625,17 @@ simplRecE env pairs body cont ; (floats2, expr') <- simplExprF env2 body cont ; return (floats1 `addFloats` floats2, expr') } -{- Note [Dark corner with levity polymorphism] +{- Note [Dark corner with representation polymorphism] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In `simplNonRecE`, the call to `isStrictId` will fail if the binder -has a levity-polymorphic type, of kind (TYPE r). So we are careful to +has a representation-polymorphic type, of kind (TYPE r). So we are careful to call `isStrictId` on the OutId, not the InId, in case we have ((\(r::RuntimeRep) \(x::Type r). blah) Lifted arg) That will lead to `simplNonRecE env (x::Type r) arg`, and we can't tell if x is lifted or unlifted from that. We only get such redexes from the compulsory inlining of a wired-in, -levity-polymorphic function like `rightSection` (see +representation-polymorphic function like `rightSection` (see GHC.Types.Id.Make). Mind you, SimpleOpt should probably have inlined such compulsory inlinings already, but belt and braces does no harm. |