summaryrefslogtreecommitdiff
path: root/compiler/GHC/Data
Commit message (Collapse)AuthorAgeFilesLines
* Split DynFlags structure into own moduleOleg Grenrus2023-05-151-1/+1
| | | | | This will allow to make command line parsing to depend on diagnostic system (which depends on dynflags)
* Add the Unsatisfiable classsheaf2023-04-291-1/+12
| | | | | | | | | This commit implements GHC proposal #433, adding the Unsatisfiable class to the GHC.TypeError module. This provides an alternative to TypeError for which error reporting is more predictable: we report it when we are reporting unsolved Wanted constraints. Fixes #14983 #16249 #16906 #18310 #20835
* Major refactor in the handling of equality constraintsSimon Peyton Jones2023-04-142-2/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This MR substantially refactors the way in which the constraint solver deals with equality constraints. The big thing is: * Intead of a pipeline in which we /first/ canonicalise and /then/ interact (the latter including performing unification) the two steps are more closely integreated into one. That avoids the current rather indirect communication between the two steps. The proximate cause for this refactoring is fixing #22194, which involve solving [W] alpha[2] ~ Maybe (F beta[4]) by doing this: alpha[2] := Maybe delta[2] [W] delta[2] ~ F beta[4] That is, we don't promote beta[4]! This is very like introducing a cycle breaker, and was very awkward to do before, but now it is all nice. See GHC.Tc.Utils.Unify Note [Promotion and level-checking] and Note [Family applications in canonical constraints]. The big change is this: * Several canonicalisation checks (occurs-check, cycle-breaking, checking for concreteness) are combined into one new function: GHC.Tc.Utils.Unify.checkTyEqRhs This function is controlled by `TyEqFlags`, which says what to do for foralls, type families etc. * `canEqCanLHSFinish` now sees if unification is possible, and if so, actually does it: see `canEqCanLHSFinish_try_unification`. There are loads of smaller changes: * The on-the-fly unifier `GHC.Tc.Utils.Unify.unifyType` has a cheap-and-cheerful version of `checkTyEqRhs`, called `simpleUnifyCheck`. If `simpleUnifyCheck` succeeds, it can unify, otherwise it defers by emitting a constraint. This is simpler than before. * I simplified the swapping code in `GHC.Tc.Solver.Equality.canEqCanLHS`. Especially the nasty stuff involving `swap_for_occurs` and `canEqTyVarFunEq`. Much nicer now. See Note [Orienting TyVarLHS/TyFamLHS] Note [Orienting TyFamLHS/TyFamLHS] * Added `cteSkolemOccurs`, `cteConcrete`, and `cteCoercionHole` to the problems that can be discovered by `checkTyEqRhs`. * I fixed #23199 `pickQuantifiablePreds`, which actually allows GHC to to accept both cases in #22194 rather than rejecting both. Yet smaller: * Added a `synIsConcrete` flag to `SynonymTyCon` (alongside `synIsFamFree`) to reduce the need for synonym expansion when checking concreteness. Use it in `isConcreteType`. * Renamed `isConcrete` to `isConcreteType` * Defined `GHC.Core.TyCo.FVs.isInjectiveInType` as a more efficient way to find if a particular type variable is used injectively than finding all the injective variables. It is called in `GHC.Tc.Utils.Unify.definitely_poly`, which in turn is used quite a lot. * Moved `rewriterView` to `GHC.Core.Type`, so we can use it from the constraint solver. Fixes #22194, #23199 Compile times decrease by an average of 0.1%; but there is a 7.4% drop in compiler allocation on T15703. Metric Decrease: T15703
* Handle records in the renamersheaf2023-03-291-1/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch moves the field-based logic for disambiguating record updates to the renamer. The type-directed logic, scheduled for removal, remains in the typechecker. To do this properly (and fix the myriad of bugs surrounding the treatment of duplicate record fields), we took the following main steps: 1. Create GREInfo, a renamer-level equivalent to TyThing which stores information pertinent to the renamer. This allows us to uniformly treat imported and local Names in the renamer, as described in Note [GREInfo]. 2. Remove GreName. Instead of a GlobalRdrElt storing GreNames, which distinguished between normal names and field names, we now store simple Names in GlobalRdrElt, along with the new GREInfo information which allows us to recover the FieldLabel for record fields. 3. Add namespacing for record fields, within the OccNames themselves. This allows us to remove the mangling of duplicate field selectors. This change ensures we don't print mangled names to the user in error messages, and allows us to handle duplicate record fields in Template Haskell. 4. Move record disambiguation to the renamer, and operate on the level of data constructors instead, to handle #21443. The error message text for ambiguous record updates has also been changed to reflect that type-directed disambiguation is on the way out. (3) means that OccEnv is now a bit more complex: we first key on the textual name, which gives an inner map keyed on NameSpace: OccEnv a ~ FastStringEnv (UniqFM NameSpace a) Note that this change, along with (2), both increase the memory residency of GlobalRdrEnv = OccEnv [GlobalRdrElt], which causes a few tests to regress somewhat in compile-time allocation. Even though (3) simplified a lot of code (in particular the treatment of field selectors within Template Haskell and in error messages), it came with one important wrinkle: in the situation of -- M.hs-boot module M where { data A; foo :: A -> Int } -- M.hs module M where { data A = MkA { foo :: Int } } we have that M.hs-boot exports a variable foo, which is supposed to match with the record field foo that M exports. To solve this issue, we add a new impedance-matching binding to M foo{var} = foo{fld} This mimics the logic that existed already for impedance-binding DFunIds, but getting it right was a bit tricky. See Note [Record field impedance matching] in GHC.Tc.Module. We also needed to be careful to avoid introducing space leaks in GHCi. So we dehydrate the GlobalRdrEnv before storing it anywhere, e.g. in ModIface. This means stubbing out all the GREInfo fields, with the function forceGlobalRdrEnv. When we read it back in, we rehydrate with rehydrateGlobalRdrEnv. This robustly avoids any space leaks caused by retaining old type environments. Fixes #13352 #14848 #17381 #17551 #19664 #21443 #21444 #21720 #21898 #21946 #21959 #22125 #22160 #23010 #23062 #23063 Updates haddock submodule ------------------------- Metric Increase: MultiComponentModules MultiLayerModules MultiLayerModulesDefsGhci MultiLayerModulesNoCode T13701 T14697 hard_hole_fits -------------------------
* Refactor the constraint solver pipelinewip/T23070Simon Peyton Jones2023-03-221-2/+5
| | | | | | | | | | | | | | | | The big change is to put the entire type-equality solver into GHC.Tc.Solver.Equality, rather than scattering it over Canonical and Interact. Other changes * EqCt becomes its own data type, a bit like QCInst. This is great because EqualCtList is then just [EqCt] * New module GHC.Tc.Solver.Dict has come of the class-contraint solver. In due course it will be all. One step at a time. This MR is intended to have zero change in behaviour: it is a pure refactor. It opens the way to subsequent tidying up, we believe.
* Minor refactorKrzysztof Gogolewski2023-02-041-1/+5
| | | | | | | | * Introduce refactorDupsOn f = refactorDups (comparing f) * Make mkBigTupleCase and coreCaseTuple monadic. Every call to those functions was preceded by calling newUniqueSupply. * Use mkUserLocalOrCoVar, which is equivalent to combining mkLocalIdOrCoVar with mkInternalName.
* FastString: add fastStringToShorTextdoyougnu2023-01-311-0/+7
|
* Fix contification with stable unfoldings (#22428)Sebastian Graf2023-01-121-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Many functions now return a `TailUsageDetails` that adorns a `UsageDetails` with a `JoinArity` that reflects the number of join point binders around the body for which the `UsageDetails` was computed. `TailUsageDetails` is now returned by `occAnalLamTail` as well as `occAnalUnfolding` and `occAnalRules`. I adjusted `Note [Join points and unfoldings/rules]` and `Note [Adjusting right-hand sides]` to account for the new machinery. I also wrote a new `Note [Join arity prediction based on joinRhsArity]` and refer to it when we combine `TailUsageDetails` for a recursive RHS. I also renamed * `occAnalLam` to `occAnalLamTail` * `adjustRhsUsage` to `adjustTailUsage` * a few other less important functions and properly documented the that each call of `occAnalLamTail` must pair up with `adjustTailUsage`. I removed `Note [Unfoldings and join points]` because it was redundant with `Note [Occurrences in stable unfoldings]`. While in town, I refactored `mkLoopBreakerNodes` so that it returns a condensed `NodeDetails` called `SimpleNodeDetails`. Fixes #22428. The refactoring seems to have quite beneficial effect on ghc/alloc performance: ``` CoOpt_Read(normal) ghc/alloc 784,778,420 768,091,176 -2.1% GOOD T12150(optasm) ghc/alloc 77,762,270 75,986,720 -2.3% GOOD T12425(optasm) ghc/alloc 85,740,186 84,641,712 -1.3% GOOD T13056(optasm) ghc/alloc 306,104,656 299,811,632 -2.1% GOOD T13253(normal) ghc/alloc 350,233,952 346,004,008 -1.2% T14683(normal) ghc/alloc 2,800,514,792 2,754,651,360 -1.6% T15304(normal) ghc/alloc 1,230,883,318 1,215,978,336 -1.2% T15630(normal) ghc/alloc 153,379,590 151,796,488 -1.0% T16577(normal) ghc/alloc 7,356,797,056 7,244,194,416 -1.5% T17516(normal) ghc/alloc 1,718,941,448 1,692,157,288 -1.6% T19695(normal) ghc/alloc 1,485,794,632 1,458,022,112 -1.9% T21839c(normal) ghc/alloc 437,562,314 431,295,896 -1.4% GOOD T21839r(normal) ghc/alloc 446,927,580 440,615,776 -1.4% GOOD geo. mean -0.6% minimum -2.4% maximum -0.0% ``` Metric Decrease: CoOpt_Read T10421 T12150 T12425 T13056 T18698a T18698b T21839c T21839r T9961
* Force the Docs structure to prevent leaks in GHCi with -haddock without ↵wip/force-docsZubin Duggal2023-01-031-1/+2
| | | | | | | | | | -fwrite-interface Involves adding many new NFData instances. Without forcing Docs, references to the TcGblEnv for each module are retained by the Docs structure. Usually these are forced when the ModIface is serialised but not when we aren't writing the interface.
* hlint: Removed redundant UnboxedSums pragmasMatthew Pickering2022-12-092-2/+0
| | | | | | | UnboxedSums is quite confusingly implied by UnboxedTuples, alas, just the way it is. See #22485
* Add version of `reachableGraph` that avoids loop for cyclic inputsGergő Érdi2022-12-081-26/+77
| | | | | | by building its result connected component by component Fixes #22512
* Remove copy-pasted definitions of `graphFromEdgedVertices*`Gergő Érdi2022-12-081-2/+2
|
* FastString: SAT bucket_matchdoyougnu2022-12-011-9/+8
| | | | | Metric Decrease: MultiLayerModulesTH_OneShot
* Make Functor a quantified superclass of Bifunctor.Baldur Blöndal2022-11-301-0/+3
| | | | | | | | | | | See https://github.com/haskell/core-libraries-committee/issues/91 for discussion. This change relates Bifunctor with Functor by requiring second = fmap. Moreover this change is a step towards unblocking the major version bump of bifunctors and profunctors to major version 6. This paves the way to move the Profunctor class into base. For that Functor first similarly becomes a superclass of Profunctor in the new major version 6.
* Add Javascript backendSylvain Henry2022-11-291-0/+19
| | | | | | | | | | | | | | | Add JS backend adapted from the GHCJS project by Luite Stegeman. Some features haven't been ported or implemented yet. Tests for these features have been disabled with an associated gitlab ticket. Bump array submodule Work funded by IOG. Co-authored-by: Jeffrey Young <jeffrey.young@iohk.io> Co-authored-by: Luite Stegeman <stegeman@gmail.com> Co-authored-by: Josh Meredith <joshmeredith2008@gmail.com>
* Check if the SDoc starts with a single quote (#22488)Vladislav Zavialov2022-11-231-1/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes pretty-printing of character literals inside promoted lists and tuples. When we pretty-print a promoted list or tuple whose first element starts with a single quote, we want to add a space between the opening bracket and the element: '[True] -- ok '[ 'True] -- ok '['True] -- not ok If we don't add the space, we accidentally produce a character literal '['. Before this patch, pprSpaceIfPromotedTyCon inspected the type as an AST and tried to guess if it would be rendered with a single quote. However, it missed the case when the inner type was itself a character literal: '[ 'x'] -- ok '['x'] -- not ok Instead of adding this particular case, I opted for a more future-proof solution: check the SDoc directly. This way we can detect if the single quote is actually there instead of trying to predict it from the AST. The new function is called spaceIfSingleQuote.
* Misc cleanupKrzysztof Gogolewski2022-11-162-3/+2
| | | | | | | * Replace catMaybes . map f with mapMaybe f * Use concatFS to concatenate multiple FastStrings * Fix documentation of -exclude-module * Cleanup getIgnoreCount in GHCi.UI
* Indent closing "#-}" to silence HLintwip/T21623Simon Peyton Jones2022-11-111-5/+5
|
* Type vs Constraint: finally nailedSimon Peyton Jones2022-11-111-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This big patch addresses the rats-nest of issues that have plagued us for years, about the relationship between Type and Constraint. See #11715/#21623. The main payload of the patch is: * To introduce CONSTRAINT :: RuntimeRep -> Type * To make TYPE and CONSTRAINT distinct throughout the compiler Two overview Notes in GHC.Builtin.Types.Prim * Note [TYPE and CONSTRAINT] * Note [Type and Constraint are not apart] This is the main complication. The specifics * New primitive types (GHC.Builtin.Types.Prim) - CONSTRAINT - ctArrowTyCon (=>) - tcArrowTyCon (-=>) - ccArrowTyCon (==>) - funTyCon FUN -- Not new See Note [Function type constructors and FunTy] and Note [TYPE and CONSTRAINT] * GHC.Builtin.Types: - New type Constraint = CONSTRAINT LiftedRep - I also stopped nonEmptyTyCon being built-in; it only needs to be wired-in * Exploit the fact that Type and Constraint are distinct throughout GHC - Get rid of tcView in favour of coreView. - Many tcXX functions become XX functions. e.g. tcGetCastedTyVar --> getCastedTyVar * Kill off Note [ForAllTy and typechecker equality], in (old) GHC.Tc.Solver.Canonical. It said that typechecker-equality should ignore the specified/inferred distinction when comparein two ForAllTys. But that wsa only weakly supported and (worse) implies that we need a separate typechecker equality, different from core equality. No no no. * GHC.Core.TyCon: kill off FunTyCon in data TyCon. There was no need for it, and anyway now we have four of them! * GHC.Core.TyCo.Rep: add two FunTyFlags to FunCo See Note [FunCo] in that module. * GHC.Core.Type. Lots and lots of changes driven by adding CONSTRAINT. The key new function is sORTKind_maybe; most other changes are built on top of that. See also `funTyConAppTy_maybe` and `tyConAppFun_maybe`. * Fix a longstanding bug in GHC.Core.Type.typeKind, and Core Lint, in kinding ForAllTys. See new tules (FORALL1) and (FORALL2) in GHC.Core.Type. (The bug was that before (forall (cv::t1 ~# t2). blah), where blah::TYPE IntRep, would get kind (TYPE IntRep), but it should be (TYPE LiftedRep). See Note [Kinding rules for types] in GHC.Core.Type. * GHC.Core.TyCo.Compare is a new module in which we do eqType and cmpType. Of course, no tcEqType any more. * GHC.Core.TyCo.FVs. I moved some free-var-like function into this module: tyConsOfType, visVarsOfType, and occCheckExpand. Refactoring only. * GHC.Builtin.Types. Compiletely re-engineer boxingDataCon_maybe to have one for each /RuntimeRep/, rather than one for each /Type/. This dramatically widens the range of types we can auto-box. See Note [Boxing constructors] in GHC.Builtin.Types The boxing types themselves are declared in library ghc-prim:GHC.Types. GHC.Core.Make. Re-engineer the treatment of "big" tuples (mkBigCoreVarTup etc) GHC.Core.Make, so that it auto-boxes unboxed values and (crucially) types of kind Constraint. That allows the desugaring for arrows to work; it gathers up free variables (including dictionaries) into tuples. See Note [Big tuples] in GHC.Core.Make. There is still work to do here: #22336. But things are better than before. * GHC.Core.Make. We need two absent-error Ids, aBSENT_ERROR_ID for types of kind Type, and aBSENT_CONSTRAINT_ERROR_ID for vaues of kind Constraint. Ditto noInlineId vs noInlieConstraintId in GHC.Types.Id.Make; see Note [inlineId magic]. * GHC.Core.TyCo.Rep. Completely refactor the NthCo coercion. It is now called SelCo, and its fields are much more descriptive than the single Int we used to have. A great improvement. See Note [SelCo] in GHC.Core.TyCo.Rep. * GHC.Core.RoughMap.roughMatchTyConName. Collapse TYPE and CONSTRAINT to a single TyCon, so that the rough-map does not distinguish them. * GHC.Core.DataCon - Mainly just improve documentation * Some significant renamings: GHC.Core.Multiplicity: Many --> ManyTy (easier to grep for) One --> OneTy GHC.Core.TyCo.Rep TyCoBinder --> GHC.Core.Var.PiTyBinder GHC.Core.Var TyCoVarBinder --> ForAllTyBinder AnonArgFlag --> FunTyFlag ArgFlag --> ForAllTyFlag GHC.Core.TyCon TyConTyCoBinder --> TyConPiTyBinder Many functions are renamed in consequence e.g. isinvisibleArgFlag becomes isInvisibleForAllTyFlag, etc * I refactored FunTyFlag (was AnonArgFlag) into a simple, flat data type data FunTyFlag = FTF_T_T -- (->) Type -> Type | FTF_T_C -- (-=>) Type -> Constraint | FTF_C_T -- (=>) Constraint -> Type | FTF_C_C -- (==>) Constraint -> Constraint * GHC.Tc.Errors.Ppr. Some significant refactoring in the TypeEqMisMatch case of pprMismatchMsg. * I made the tyConUnique field of TyCon strict, because I saw code with lots of silly eval's. That revealed that GHC.Settings.Constants.mAX_SUM_SIZE can only be 63, because we pack the sum tag into a 6-bit field. (Lurking bug squashed.) Fixes * #21530 Updates haddock submodule slightly. Performance changes ~~~~~~~~~~~~~~~~~~~ I was worried that compile times would get worse, but after some careful profiling we are down to a geometric mean 0.1% increase in allocation (in perf/compiler). That seems fine. There is a big runtime improvement in T10359 Metric Decrease: LargeRecord MultiLayerModulesTH_OneShot T13386 T13719 Metric Increase: T8095
* add new modules for reducibility and WebAssembly translationNorman Ramsey2022-11-111-0/+264
|
* add the two key graph modules from Martin Erwig's FGLNorman Ramsey2022-11-113-0/+1020
| | | | | | | | | | | | | | | | | | | | | | | | | | Martin Erwig's FGL (Functional Graph Library) provides an "inductive" representation of graphs. A general graph has labeled nodes and labeled edges. The key operation on a graph is to decompose it by removing one node, together with the edges that connect the node to the rest of the graph. There is also an inverse composition operation. The decomposition and composition operations make this representation of graphs exceptionally well suited to implement graph algorithms in which the graph is continually changing, as alluded to in #21259. This commit adds `GHC.Data.Graph.Inductive.Graph`, which defines the interface, and `GHC.Data.Graph.Inductive.PatriciaTree`, which provides an implementation. Both modules are taken from `fgl-5.7.0.3` on Hackage, with these changes: - Copyright and license text have been copied into the files themselves, not stored separately. - Some calls to `error` have been replaced with calls to `panic`. - Conditional-compilation support for older versions of GHC, `containers`, and `base` has been removed.
* Define `Infinite` list and use where appropriate.M Farkas-Dyck2022-11-081-0/+194
| | | | | | | | Also add perf test for infinite list fusion. In particular, in `GHC.Core`, often we deal with infinite lists of roles. Also in a few locations we deal with infinite lists of names. Thanks to simonpj for helping to write the Note [Fusion for `Infinite` lists].
* Export pprTrace and friends from GHC.Prelude.Andreas Klebinger2022-11-034-4/+3
| | | | | Introduces GHC.Prelude.Basic which can be used in modules which are a dependency of the ppr code.
* Remove source location information from interface filesOwen Shepherd2022-10-271-8/+8
| | | | | | | | | | | | | This change aims to minimize source location information leaking into interface files, which makes ABI hashes dependent on the build location. The `Binary (Located a)` instance has been removed completely. It seems that the HIE interface still needs the ability to serialize SrcSpans, but by wrapping the instances, it should be a lot more difficult to inadvertently add source location information.
* Cleanup String/FastString conversionsKrzysztof Gogolewski2022-10-251-32/+2
| | | | | | | Remove unused mkPtrString and isUnderscoreFS. We no longer use mkPtrString since 1d03d8bef96. Remove unnecessary conversions between FastString and String and back.
* Enforce invariant of `ListBag` constructor.M Farkas-Dyck2022-10-191-16/+26
|
* Make `Functor` a superclass of `TrieMap`, which lets us derive the `map` ↵M Farkas-Dyck2022-10-181-19/+38
| | | | functions.
* Enforce internal invariant of OrdList and fix bugs in viewCons / viewSnocBodigrim2022-10-011-13/+23
| | | | | `viewCons` used to ignore `Many` constructor completely, returning `VNothing`. `viewSnoc` violated internal invariant of `Many` being a non-empty list.
* Scrub various partiality involving empty lists.M Farkas-Dyck2022-09-301-2/+3
| | | | Avoids some uses of `head` and `tail`, and some panics when an argument is null.
* Eliminate headFS, use unconsFS insteadBodigrim2022-09-281-6/+0
| | | | | A small step towards #22185 to avoid partial functions + safe implementation of `startsWithUnderscore`.
* Apply some tricks to speed up core lint.Andreas Klebinger2022-09-281-0/+50
| | | | | | | | | | | | | | | | | | | | | | | | | Below are the noteworthy changes and if given their impact on compiler allocations for a type heavy module: * Use the oneShot trick on LintM * Use a unboxed tuple for the result of LintM: ~6% reduction * Avoid a thunk for the result of typeKind in lintType: ~5% reduction * lint_app: Don't allocate the error msg in the hot code path: ~4% reduction * lint_app: Eagerly force the in scope set: ~4% * nonDetCmpType: Try to short cut using reallyUnsafePtrEquality#: ~2% * lintM: Use a unboxed maybe for the `a` result: ~12% * lint_app: make go_app tail recursive to avoid allocating the go function as heap closure: ~7% * expandSynTyCon_maybe: Use a specialized data type For a less type heavy module like nofib/spectral/simple compiled with -O -dcore-lint allocations went down by ~24% and compile time by ~9%. ------------------------- Metric Decrease: T1969 -------------------------
* Clean up some. In particular:M Farkas-Dyck2022-09-174-39/+8
| | | | | | | | | | • Delete some dead code, largely under `GHC.Utils`. • Clean up a few definitions in `GHC.Utils.(Misc, Monad)`. • Clean up `GHC.Types.SrcLoc`. • Derive stock `Functor, Foldable, Traversable` for more types. • Derive more instances for newtypes. Bump haddock submodule.
* Fix typosEric Lindblad2022-09-144-6/+6
| | | | | | | This fixes various typos and spelling mistakes in the compiler. Fixes #21891
* ghc-boot: Clean up UTF-8 codecsBen Gamari2022-07-222-8/+8
| | | | | | | | In preparation for moving the UTF-8 codecs into `base`: * Move them to GHC.Utils.Encoding.UTF8 * Make names more consistent * Add some Haddocks
* CorePrep: Don't speculatively evaluate recursive calls (#20836)Sebastian Graf2022-06-201-1/+7
| | | | | | | | | | | In #20836 we have optimised a terminating program into an endless loop, because we speculated the self-recursive call of a recursive DFun. Now we track the set of enclosing recursive binders in CorePrep to prevent speculation of such self-recursive calls. See the updates to Note [Speculative evaluation] for details. Fixes #20836.
* Use UnionListsOrd instead of UnionLists in most places.Andreas Klebinger2022-05-241-2/+15
| | | | This should get rid of most, if not all "Overlong lists" errors and fix #20016
* Fix all invalid haddock comments in the compilerZubin Duggal2022-03-291-6/+6
| | | | Fixes #20935 and #20924
* hi haddock: Lex and store haddock docs in interface filesZubin Duggal2022-03-232-0/+45
| | | | | | | | | | | | | | | | | | Names appearing in Haddock docstrings are lexed and renamed like any other names appearing in the AST. We currently rename names irrespective of the namespace, so both type and constructor names corresponding to an identifier will appear in the docstring. Haddock will select a given name as the link destination based on its own heuristics. This patch also restricts the limitation of `-haddock` being incompatible with `Opt_KeepRawTokenStream`. The export and documenation structure is now computed in GHC and serialised in .hi files. This can be used by haddock to directly generate doc pages without reparsing or renaming the source. At the moment the operation of haddock is not modified, that's left to a future patch. Updates the haddock submodule with the minimum changes needed.
* Make inert_cycle_breakers into a stack.Richard Eisenberg2022-03-021-1/+4
| | | | Close #20231.
* Introduce ConcreteTv metavariablessheaf2022-03-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces a new kind of metavariable, by adding the constructor `ConcreteTv` to `MetaInfo`. A metavariable with `ConcreteTv` `MetaInfo`, henceforth a concrete metavariable, can only be unified with a type that is concrete (that is, a type that answers `True` to `GHC.Core.Type.isConcrete`). This solves the problem of dangling metavariables in `Concrete#` constraints: instead of emitting `Concrete# ty`, which contains a secret existential metavariable, we simply emit a primitive equality constraint `ty ~# concrete_tv` where `concrete_tv` is a fresh concrete metavariable. This means we can avoid all the complexity of canonicalising `Concrete#` constraints, as we can just re-use the existing machinery for `~#`. To finish things up, this patch then removes the `Concrete#` special predicate, and instead introduces the special predicate `IsRefl#` which enforces that a coercion is reflexive. Such a constraint is needed because the canonicaliser is quite happy to rewrite an equality constraint such as `ty ~# concrete_tv`, but such a rewriting is not handled by the rest of the compiler currently, as we need to make use of the resulting coercion, as outlined in the FixedRuntimeRep plan. The big upside of this approach (on top of simplifying the code) is that we can now selectively implement PHASE 2 of FixedRuntimeRep, by changing individual calls of `hasFixedRuntimeRep_MustBeRefl` to `hasFixedRuntimeRep` and making use of the obtained coercion.
* Derive some stock instances for OverridingBoolsheaf2022-02-251-3/+10
| | | | | | | | | This patch adds some derived instances to `GHC.Data.Bool.OverridingBool`. It also changes the order of the constructors, so that the derived `Ord` instance matches the behaviour for `Maybe Bool`. Fixes #20326
* Suggestions due to hlintMatthew Pickering2022-02-241-2/+1
| | | | | It turns out this job hasn't been running for quite a while (perhaps ever) so there are quite a few failures when running the linter locally.
* compiler: Introduce and use RoughMap for instance environmentsBen Gamari2022-02-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Here we introduce a new data structure, RoughMap, inspired by the previous `RoughTc` matching mechanism for checking instance matches. This allows [Fam]InstEnv to be implemented as a trie indexed by these RoughTc signatures, reducing the complexity of instance lookup and FamInstEnv merging (done during the family instance conflict test) from O(n) to O(log n). The critical performance improvement currently realised by this patch is in instance matching. In particular the RoughMap mechanism allows us to discount many potential instances which will never match for constraints involving type variables (see Note [Matching a RoughMap]). In realistic code bases matchInstEnv was accounting for 50% of typechecker time due to redundant work checking instances when simplifying instance contexts when deriving instances. With this patch the cost is significantly reduced. The larger constants in InstEnv creation do mean that a few small tests regress in allocations slightly. However, the runtime of T19703 is reduced by a factor of 4. Moreover, the compilation time of the Cabal library is slightly improved. A couple of test cases are included which demonstrate significant improvements in compile time with this patch. This unfortunately does not fix the testcase provided in #19703 but does fix #20933 ------------------------- Metric Decrease: T12425 Metric Increase: T13719 T9872a T9872d hard_hole_fits ------------------------- Co-authored-by: Matthew Pickering <matthewtpickering@gmail.com>
* Fix a few Note inconsistenciesBen Gamari2022-02-011-1/+1
|
* Rework the handling of SkolemInfoMatthew Pickering2022-01-291-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The main purpose of this patch is to attach a SkolemInfo directly to each SkolemTv. This fixes the large number of bugs which have accumulated over the years where we failed to report errors due to having "no skolem info" for particular type variables. Now the origin of each type varible is stored on the type variable we can always report accurately where it cames from. Fixes #20969 #20732 #20680 #19482 #20232 #19752 #10946 #19760 #20063 #13499 #14040 The main changes of this patch are: * SkolemTv now contains a SkolemInfo field which tells us how the SkolemTv was created. Used when reporting errors. * Enforce invariants relating the SkolemInfoAnon and level of an implication (ic_info, ic_tclvl) to the SkolemInfo and level of the type variables in ic_skols. * All ic_skols are TcTyVars -- Check is currently disabled * All ic_skols are SkolemTv * The tv_lvl of the ic_skols agrees with the ic_tclvl * The ic_info agrees with the SkolInfo of the implication. These invariants are checked by a debug compiler by checkImplicationInvariants. * Completely refactor kcCheckDeclHeader_sig which kept doing my head in. Plus, it wasn't right because it wasn't skolemising the binders as it decomposed the kind signature. The new story is described in Note [kcCheckDeclHeader_sig]. The code is considerably shorter than before (roughly 240 lines turns into 150 lines). It still has the same awkward complexity around computing arity as before, but that is a language design issue. See Note [Arity inference in kcCheckDeclHeader_sig] * I added new type synonyms MonoTcTyCon and PolyTcTyCon, and used them to be clear which TcTyCons have "finished" kinds etc, and which are monomorphic. See Note [TcTyCon, MonoTcTyCon, and PolyTcTyCon] * I renamed etaExpandAlgTyCon to splitTyConKind, becuase that's a better name, and it is very useful in kcCheckDeclHeader_sig, where eta-expansion isn't an issue. * Kill off the nasty `ClassScopedTvEnv` entirely. Co-authored-by: Simon Peyton Jones <simon.peytonjones@gmail.com>
* warnPprTrace: pass separately the reasonKrzysztof Gogolewski2022-01-111-3/+3
| | | | This makes it more similar to pprTrace, pprPanic etc.
* Perf: use SmallArray for primops' Ids cache (#20857)Sylvain Henry2022-01-061-0/+92
| | | | | | SmallArray doesn't perform bounds check (faster). Make primop tags start at 0 to avoid index arithmetic.
* Correct retypechecking in --make modeMatthew Pickering2021-11-251-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Note [Hydrating Modules] ~~~~~~~~~~~~~~~~~~~~~~~~ What is hydrating a module? * There are two versions of a module, the ModIface is the on-disk version and the ModDetails is a fleshed-out in-memory version. * We can **hydrate** a ModIface in order to obtain a ModDetails. Hydration happens in three different places * When an interface file is initially loaded from disk, it has to be hydrated. * When a module is finished compiling, we hydrate the ModIface in order to generate the version of ModDetails which exists in memory (see Note) * When dealing with boot files and module loops (see Note [Rehydrating Modules]) Note [Rehydrating Modules] ~~~~~~~~~~~~~~~~~~~~~~~~~~~ If a module has a boot file then it is critical to rehydrate the modules on the path between the two. Suppose we have ("R" for "recursive"): ``` R.hs-boot: module R where data T g :: T -> T A.hs: module A( f, T, g ) where import {-# SOURCE #-} R data S = MkS T f :: T -> S = ...g... R.hs: module R where data T = T1 | T2 S g = ...f... ``` After compiling A.hs we'll have a TypeEnv in which the Id for `f` has a type type uses the AbstractTyCon T; and a TyCon for `S` that also mentions that same AbstractTyCon. (Abstract because it came from R.hs-boot; we know nothing about it.) When compiling R.hs, we build a TyCon for `T`. But that TyCon mentions `S`, and it currently has an AbstractTyCon for `T` inside it. But we want to build a fully cyclic structure, in which `S` refers to `T` and `T` refers to `S`. Solution: **rehydration**. *Before compiling `R.hs`*, rehydrate all the ModIfaces below it that depend on R.hs-boot. To rehydrate a ModIface, call `typecheckIface` to convert it to a ModDetails. It's just a de-serialisation step, no type inference, just lookups. Now `S` will be bound to a thunk that, when forced, will "see" the final binding for `T`; see [Tying the knot](https://gitlab.haskell.org/ghc/ghc/-/wikis/commentary/compiler/tying-the-knot). But note that this must be done *before* compiling R.hs. When compiling R.hs, the knot-tying stuff above will ensure that `f`'s unfolding mentions the `LocalId` for `g`. But when we finish R, we carefully ensure that all those `LocalIds` are turned into completed `GlobalIds`, replete with unfoldings etc. Alas, that will not apply to the occurrences of `g` in `f`'s unfolding. And if we leave matters like that, they will stay that way, and *all* subsequent modules that import A will see a crippled unfolding for `f`. Solution: rehydrate both R and A's ModIface together, right after completing R.hs. We only need rehydrate modules that are * Below R.hs * Above R.hs-boot There might be many unrelated modules (in the home package) that don't need to be rehydrated. This dark corner is the subject of #14092. Suppose we add to our example ``` X.hs module X where import A data XT = MkX T fx = ...g... ``` If in `--make` we compile R.hs-boot, then A.hs, then X.hs, we'll get a `ModDetails` for `X` that has an AbstractTyCon for `T` in the the argument type of `MkX`. So: * Either we should delay compiling X until after R has beeen compiled. * Or we should rehydrate X after compiling R -- because it transitively depends on R.hs-boot. Ticket #20200 has exposed some issues to do with the knot-tying logic in GHC.Make, in `--make` mode. this particular issue starts [here](https://gitlab.haskell.org/ghc/ghc/-/issues/20200#note_385758). The wiki page [Tying the knot](https://gitlab.haskell.org/ghc/ghc/-/wikis/commentary/compiler/tying-the-knot) is helpful. Also closely related are * #14092 * #14103 Fixes tickets #20200 #20561
* Turn GHC.Data.Graph.Base.Graph into a newtypeSimon Jakobi2021-11-121-1/+1
|
* driver: Cache the transitive dependency calculation in ModuleGraphMatthew Pickering2021-11-111-2/+3
| | | | | | | | Two reasons for this change: 1. Avoid computing the transitive dependencies when compiling each module, this can save a lot of repeated work. 2. More robust to forthcoming changes to support multiple home units.