sheaf pushed to branch wip/debug-join-point at Glasgow Haskell Compiler / GHC Commits: f0cca3b4 by sheaf at 2026-02-03T11:58:32+01:00 WIP: debug panic - - - - - 2 changed files: - compiler/GHC/Core/Opt/Simplify/Iteration.hs - compiler/GHC/Core/SimpleOpt.hs Changes: ===================================== compiler/GHC/Core/Opt/Simplify/Iteration.hs ===================================== @@ -1905,7 +1905,7 @@ simplNonRecE :: HasDebugCallStack -- Otherwise it may or may not satisfy it. simplNonRecE env from_what bndr (rhs, rhs_se) body cont - | assert (isId bndr && not (isJoinId bndr) ) $ + | assert (isId bndr && isNothing (joinPointBinding_maybe bndr rhs)) $ is_strict_bind = -- Evaluate RHS strictly simplExprF (rhs_se `setInScopeFromE` env) rhs @@ -1943,7 +1943,7 @@ simplRecE :: SimplEnv -- Precondition: not a join-point binding simplRecE env pairs body cont = do { let bndrs = map fst pairs - ; massert (all (not . isJoinId) bndrs) + ; massert (isNothing $ joinPointBindings_maybe pairs) ; env1 <- simplRecBndrs env bndrs -- NB: bndrs' don't have unfoldings or rules -- We add them as we go down ===================================== compiler/GHC/Core/SimpleOpt.hs ===================================== @@ -1059,28 +1059,27 @@ and again its arity increases (#15517) -} --- | Returns Just (bndr,rhs) if the binding is a join point: --- If it's a JoinId, just return it --- If it's not yet a JoinId but is always tail-called, --- make it into a JoinId and return it. --- In the latter case, eta-expand the RHS if necessary, to make the --- lambdas explicit, as is required for join points --- --- Precondition: the InBndr has been occurrence-analysed, --- so its OccInfo is valid +-- | Returns @Just (bndr,rhs)@ if the binding is a join point or can be made +-- into a join point (it is always tail called). In the latter case, eta-expand +-- the RHS if necessary, to make the lambdas explicit, as is required for join points. joinPointBinding_maybe :: InBndr -> InExpr -> Maybe (InBndr, InExpr) joinPointBinding_maybe bndr rhs | not (isId bndr) = Nothing + -- NB: the 'OccInfo' of the 'InBndr' may have been zapped, e.g. if we + -- have inlined it. In this case, we may lose the join-point-hood of the + -- original binder. A later occurrence analysis pass may recover it. | isJoinId bndr - = Just (bndr, rhs) + = case tailCallInfo (idOccInfo bndr) of + NoTailCallInfo -> Nothing + AlwaysTailCalled {} -> Just (bndr, rhs) | AlwaysTailCalled join_arity <- tailCallInfo (idOccInfo bndr) , (bndrs, body) <- etaExpandToJoinPoint join_arity rhs , let str_sig = idDmdSig bndr str_arity = count isId bndrs -- Strictness demands are for Ids only - join_bndr = bndr `asJoinId` join_arity + join_bndr = bndr `asJoinId` join_arity `setIdDmdSig` etaConvertDmdSig str_arity str_sig = Just (join_bndr, mkLams bndrs body) View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/f0cca3b412c3dfcc1737d93bc2887e0c... -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/commit/f0cca3b412c3dfcc1737d93bc2887e0c... You're receiving this email because of your account on gitlab.haskell.org.