Ben Gamari pushed to branch wip/T23109 at Glasgow Haskell Compiler / GHC Commits: 34fc50c1 by Ben Gamari at 2025-08-11T13:36:25-04:00 Kill IOPort# This type is unnecessary, having been superceded by `MVar` and a rework of WinIO's blocking logic. See #20947. See https://github.com/haskell/core-libraries-committee/issues/213. - - - - - 56b32c5a by sheaf at 2025-08-12T10:00:19-04:00 Improve deep subsumption This commit improves the DeepSubsumption sub-typing implementation in GHC.Tc.Utils.Unify.tc_sub_type_deep by being less eager to fall back to unification. For example, we now are properly able to prove the subtyping relationship ((∀ a. a->a) -> Int) -> Bool <= β[tau] Bool for an unfilled metavariable β. In this case (with an AppTy on the right), we used to fall back to unification. No longer: now, given that the LHS is a FunTy and that the RHS is a deep rho type (does not need any instantiation), we try to make the RHS into a FunTy, viz. β := (->) γ We can then continue using covariance & contravariance of the function arrow, which allows us to prove the subtyping relationship, instead of trying to unify which would cause us to error out with: Couldn't match expected type ‘β’ with actual type ‘(->) ((∀ a. a -> a) -> Int) See Note [FunTy vs non-FunTy case in tc_sub_type_deep] in GHC.Tc.Utils.Unify. The other main improvement in this patch concerns type inference. The main subsumption logic happens (before & after this patch) in GHC.Tc.Gen.App.checkResultTy. However, before this patch, all of the DeepSubsumption logic only kicked in in 'check' mode, not in 'infer' mode. This patch adds deep instantiation in the 'infer' mode of checkResultTy when we are doing deep subsumption, which allows us to accept programs such as: f :: Int -> (forall a. a->a) g :: Int -> Bool -> Bool test1 b = case b of True -> f False -> g test2 b = case b of True -> g False -> f See Note [Deeply instantiate in checkResultTy when inferring]. Finally, we add representation-polymorphism checks to ensure that the lambda abstractions we introduce when doing subsumption obey the representation polymorphism invariants of Note [Representation polymorphism invariants] in GHC.Core. See Note [FunTy vs FunTy case in tc_sub_type_deep]. This is accompanied by a courtesy change to `(<.>) :: HsWrapper -> HsWrapper -> HsWrapper`, adding the equation: WpCast c1 <.> WpCast c2 = WpCast (c1 `mkTransCo` c2) This is useful because mkWpFun does not introduce an eta-expansion when both of the argument & result wrappers are casts; so this change allows us to avoid introducing lambda abstractions when casts suffice. Fixes #26225 - - - - - d175aff8 by Sylvain Henry at 2025-08-12T10:01:31-04:00 Add regression test for #18619 - - - - - a3983a26 by Sylvain Henry at 2025-08-12T10:02:20-04:00 RTS: remove some TSAN annotations (#20464) Use RELAXED_LOAD_ALWAYS macro instead. - - - - - 0434af81 by Ben Gamari at 2025-08-12T10:03:02-04:00 Bump time submodule to 1.15 Also required bumps of Cabal, directory, and hpc. - - - - - ff0c70ba by Simon Peyton Jones at 2025-08-13T13:02:07-04:00 Make injecting implicit bindings into its own pass Previously we were injecting "impliicit bindings" (data constructor worker and wrappers etc) - both at the end of CoreTidy, - and at the start of CorePrep This is unpleasant and confusing. This patch puts it it its own pass, addImplicitBinds, which runs between the two. The function `GHC.CoreToStg.AddImplicitBinds.addImplicitBinds` now takes /all/ TyCons, not just the ones for algebraic data types. That change ripples through to - corePrepPgm - doCodeGen - byteCodeGen All take [TyCon] which includes all TyCons - - - - - 876aac38 by Simon Peyton Jones at 2025-08-13T13:02:08-04:00 Implement unary classes The big change is described exhaustively in Note [Unary class magic] in GHC.Core.TyCon Other changes * We never unbox class dictionaries in worker/wrapper. This has been true for some time now, but the logic is now centralised in functions in GHC.Core.Opt.WorkWrap.Utils, namely `canUnboxTyCon`, and `canUnboxArg` See Note [Do not unbox class dictionaries] in GHC.Core.Opt.WorkWrap.Utils. * Refactored the `notWorthFloating` logic in GHc.Core.Opt.SetLevels. I can't remember if I actually changed any behaviour here, but if so it's only in a corner cases. * Fixed a bug in `GHC.Core.TyCon.isEnumerationTyCon`, which was wrongly returning True for (##). * Remove redundant Role argument to `liftCoSubstWithEx`. It was always Representational. * I refactored evidence generation in the constraint solver: * Made GHC.Tc.Types.Evidence contain better abstactions for evidence generation. * I deleted the file `GHC.Tc.Types.EvTerm` and merged its (small) contents elsewhere. It wasn't paying its way. * Made evidence for implicit parameters go via a proper abstraction. * Fix inlineBoringOk; see (IB6) in Note [inlineBoringOk] This fixes a slowdown in `countdownEffectfulDynLocal` in the `effectful` library. Smaller things * Rename `isDataTyCon` to `isBoxedDataTyCon`. * GHC.Core.Corecion.liftCoSubstWithEx was only called with Representational role, so I baked that into the function and removed the argument. * Get rid of `GHC.Core.TyCon.tyConSingleAlgDataCon_maybe` in favour of calling `not isNewTyCon` at the call sites; more explicit. * Refatored `GHC.Core.TyCon.isInjectiveTyCon`; but I don't think I changed its behaviour * Moved `decomposeIPPred` to GHC.Core.Predicate Compile time performance changes: geo. mean +0.1% minimum -6.8% maximum +14.4% The +14% one is in T21839c, where it seems that a bit more inlining is taking place. That seems acceptable; and the average change is small Metric Decrease: LargeRecord T12227 T12707 T16577 T21839r T5642 Metric Increase: T15164 T21839c T3294 T5321FD T5321Fun WWRec - - - - - 9bf00666 by Simon Peyton Jones at 2025-08-13T13:02:46-04:00 Slight improvement to pre/postInlineUnconditionally Avoids an extra simplifier iteration - - - - - 60db2c66 by Simon Peyton Jones at 2025-08-13T13:02:46-04:00 Fix a long-standing assertion error in normSplitTyConApp_maybe - - - - - b2b95dce by Simon Peyton Jones at 2025-08-13T13:02:46-04:00 Add comment to coercion optimiser - - - - - 166 changed files: - compiler/GHC/Builtin/Names.hs - compiler/GHC/Builtin/PrimOps/Ids.hs - compiler/GHC/Builtin/Types.hs - compiler/GHC/Builtin/Types/Prim.hs - compiler/GHC/Builtin/primops.txt.pp - compiler/GHC/ByteCode/InfoTable.hs - compiler/GHC/Core/Class.hs - compiler/GHC/Core/Coercion.hs - compiler/GHC/Core/Coercion/Opt.hs - compiler/GHC/Core/DataCon.hs - compiler/GHC/Core/FamInstEnv.hs - compiler/GHC/Core/Opt/Arity.hs - compiler/GHC/Core/Opt/CprAnal.hs - compiler/GHC/Core/Opt/DmdAnal.hs - compiler/GHC/Core/Opt/OccurAnal.hs - compiler/GHC/Core/Opt/SetLevels.hs - compiler/GHC/Core/Opt/Simplify/Utils.hs - compiler/GHC/Core/Opt/Specialise.hs - compiler/GHC/Core/Opt/WorkWrap/Utils.hs - compiler/GHC/Core/Predicate.hs - compiler/GHC/Core/TyCo/Rep.hs - compiler/GHC/Core/TyCon.hs - compiler/GHC/Core/Type.hs - compiler/GHC/Core/Unfold.hs - compiler/GHC/Core/Unfold/Make.hs - compiler/GHC/Core/Utils.hs - compiler/GHC/CoreToStg.hs - + compiler/GHC/CoreToStg/AddImplicitBinds.hs - compiler/GHC/CoreToStg/Prep.hs - compiler/GHC/Driver/Main.hs - compiler/GHC/HsToCore.hs - compiler/GHC/HsToCore/Binds.hs - compiler/GHC/HsToCore/Expr.hs - compiler/GHC/HsToCore/Foreign/Call.hs - compiler/GHC/Iface/Decl.hs - compiler/GHC/Iface/Syntax.hs - compiler/GHC/Iface/Tidy.hs - compiler/GHC/IfaceToCore.hs - compiler/GHC/Rename/Module.hs - compiler/GHC/StgToByteCode.hs - compiler/GHC/StgToCmm.hs - compiler/GHC/StgToCmm/Prim.hs - compiler/GHC/StgToJS/Prim.hs - compiler/GHC/Tc/Errors.hs - compiler/GHC/Tc/Gen/App.hs - compiler/GHC/Tc/Gen/Bind.hs - compiler/GHC/Tc/Gen/Expr.hs - compiler/GHC/Tc/Gen/HsType.hs - compiler/GHC/Tc/Instance/Class.hs - compiler/GHC/Tc/Instance/Family.hs - compiler/GHC/Tc/Solver/Default.hs - compiler/GHC/Tc/Solver/Dict.hs - compiler/GHC/Tc/Solver/Equality.hs - compiler/GHC/Tc/Solver/Monad.hs - compiler/GHC/Tc/Solver/Solve.hs - compiler/GHC/Tc/TyCl.hs - compiler/GHC/Tc/TyCl/Build.hs - compiler/GHC/Tc/TyCl/Instance.hs - compiler/GHC/Tc/TyCl/PatSyn.hs - compiler/GHC/Tc/TyCl/Utils.hs - − compiler/GHC/Tc/Types/EvTerm.hs - compiler/GHC/Tc/Types/Evidence.hs - compiler/GHC/Tc/Types/Origin.hs - compiler/GHC/Tc/Utils/Concrete.hs - compiler/GHC/Tc/Utils/TcMType.hs - compiler/GHC/Tc/Utils/Unify.hs - compiler/GHC/Types/Demand.hs - compiler/GHC/Types/Id.hs - compiler/GHC/Types/Id/Make.hs - compiler/GHC/Types/RepType.hs - compiler/GHC/Types/TyThing.hs - compiler/ghc.cabal.in - ghc/ghc-bin.cabal.in - libraries/Cabal - libraries/base/base.cabal.in - libraries/base/changelog.md - libraries/base/src/GHC/Exts.hs - − libraries/base/src/GHC/IOPort.hs - libraries/directory - libraries/ghc-heap/GHC/Exts/Heap/Closures.hs - libraries/ghc-internal/ghc-internal.cabal.in - libraries/ghc-internal/src/GHC/Internal/Event/Windows.hsc - libraries/ghc-internal/src/GHC/Internal/Event/Windows/Thread.hs - libraries/ghc-internal/src/GHC/Internal/Exts.hs - libraries/ghc-internal/src/GHC/Internal/IO/Buffer.hs - libraries/ghc-internal/src/GHC/Internal/IO/Windows/Handle.hsc - − libraries/ghc-internal/src/GHC/Internal/IOPort.hs - libraries/ghc-internal/src/GHC/Internal/Prim/PtrEq.hs - libraries/ghc-prim/changelog.md - libraries/hpc - libraries/time - libraries/unix - rts/Prelude.h - rts/PrimOps.cmm - rts/RtsSymbols.c - rts/external-symbols.list.in - rts/include/stg/MiscClosures.h - rts/include/stg/SMP.h - rts/posix/ticker/Pthread.c - rts/posix/ticker/TimerFd.c - rts/win32/AsyncWinIO.c - rts/win32/libHSghc-internal.def - testsuite/tests/core-to-stg/T24124.stderr - testsuite/tests/corelint/LintEtaExpand.stderr - testsuite/tests/deSugar/should_compile/T2431.stderr - testsuite/tests/dmdanal/should_compile/T16029.stdout - testsuite/tests/dmdanal/sigs/T21119.stderr - testsuite/tests/dmdanal/sigs/T21888.stderr - testsuite/tests/ghci.debugger/scripts/break011.stdout - testsuite/tests/ghci.debugger/scripts/break024.stdout - testsuite/tests/indexed-types/should_compile/T2238.hs - testsuite/tests/indexed-types/should_fail/T5439.stderr - testsuite/tests/interface-stability/base-exports.stdout - testsuite/tests/interface-stability/base-exports.stdout-javascript-unknown-ghcjs - testsuite/tests/interface-stability/base-exports.stdout-mingw32 - testsuite/tests/interface-stability/base-exports.stdout-ws-32 - testsuite/tests/interface-stability/ghc-experimental-exports.stdout - testsuite/tests/interface-stability/ghc-experimental-exports.stdout-mingw32 - testsuite/tests/interface-stability/ghc-prim-exports.stdout - testsuite/tests/interface-stability/ghc-prim-exports.stdout-mingw32 - testsuite/tests/numeric/should_compile/T15547.stderr - testsuite/tests/numeric/should_compile/T23907.stderr - + testsuite/tests/numeric/should_run/T18619.hs - + testsuite/tests/numeric/should_run/T18619.stderr - testsuite/tests/numeric/should_run/all.T - testsuite/tests/partial-sigs/should_compile/T10403.stderr - testsuite/tests/partial-sigs/should_fail/T10615.stderr - testsuite/tests/primops/should_run/UnliftedIOPort.hs - testsuite/tests/primops/should_run/all.T - + testsuite/tests/rep-poly/NoEtaRequired.hs - testsuite/tests/rep-poly/T21906.stderr - testsuite/tests/rep-poly/all.T - testsuite/tests/roles/should_compile/Roles14.stderr - testsuite/tests/roles/should_compile/Roles3.stderr - testsuite/tests/roles/should_compile/Roles4.stderr - testsuite/tests/simplCore/should_compile/DataToTagFamilyScrut.stderr - testsuite/tests/simplCore/should_compile/T15205.stderr - testsuite/tests/simplCore/should_compile/T17366.stderr - testsuite/tests/simplCore/should_compile/T17966.stderr - testsuite/tests/simplCore/should_compile/T22309.stderr - testsuite/tests/simplCore/should_compile/T22375DataFamily.stderr - testsuite/tests/simplCore/should_compile/T23307.stderr - testsuite/tests/simplCore/should_compile/T23307a.stderr - testsuite/tests/simplCore/should_compile/T25389.stderr - testsuite/tests/simplCore/should_compile/T25713.stderr - testsuite/tests/simplCore/should_compile/T7360.stderr - testsuite/tests/simplStg/should_compile/T15226b.stderr - testsuite/tests/tcplugins/CtIdPlugin.hs - testsuite/tests/typecheck/should_compile/Makefile - testsuite/tests/typecheck/should_compile/T12763.stderr - testsuite/tests/typecheck/should_compile/T14774.stdout - testsuite/tests/typecheck/should_compile/T18406b.stderr - testsuite/tests/typecheck/should_compile/T18529.stderr - + testsuite/tests/typecheck/should_compile/T26225.hs - + testsuite/tests/typecheck/should_compile/T26225b.hs - testsuite/tests/typecheck/should_compile/all.T - − testsuite/tests/typecheck/should_fail/T12563.stderr - testsuite/tests/typecheck/should_fail/T14618.stderr - testsuite/tests/typecheck/should_fail/T6022.stderr - testsuite/tests/typecheck/should_fail/T8883.stderr - testsuite/tests/typecheck/should_fail/all.T - testsuite/tests/typecheck/should_fail/tcfail140.stderr - testsuite/tests/unboxedsums/unpack_sums_7.stdout - testsuite/tests/wasm/should_run/control-flow/LoadCmmGroup.hs - testsuite/tests/wasm/should_run/control-flow/RunWasm.hs - utils/genprimopcode/Main.hs The diff was not included because it is too large. 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