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* Add and use new constructors to TcRnMessageAlfredo Di Napoli2021-09-071-65/+29
| | | | | | | | | | | | | This commit adds the following constructors to the TcRnMessage type and uses them to replace sdoc-based diagnostics in some parts of GHC (e.g. TcRnUnknownMessage). It includes: * Add TcRnMonomorphicBindings diagnostic * Convert TcRnUnknownMessage in Tc.Solver.Interact * Add and use the TcRnOrphanInstance constructor to TcRnMessage * Add TcRnFunDepConflict and TcRnDupInstanceDecls constructors to TcRnMessage * Add and use TcRnConflictingFamInstDecls constructor to TcRnMessage * Get rid of TcRnUnknownMessage from GHC.Tc.Instance.Family
* Use Reductions to keep track of rewritingssheaf2021-08-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | We define Reduction = Reduction Coercion !Type. A reduction of the form 'Reduction co new_ty' witnesses an equality ty ~co~> new_ty. That is, the rewriting happens left-to-right: the right-hand-side type of the coercion is the rewritten type, and the left-hand-side type the original type. Sticking to this convention makes the codebase more consistent, helping to avoid certain applications of SymCo. This replaces the parts of the codebase which represented reductions as pairs, (Coercion,Type) or (Type,Coercion). Reduction being strict in the Type argument improves performance in some programs that rewrite many type families (such as T9872). Fixes #20161 ------------------------- Metric Decrease: T5321Fun T9872a T9872b T9872c T9872d -------------------------
* Try to simplify zoo of functions in `Tc.Utils.Monad`Alfredo Di Napoli2021-06-281-5/+11
| | | | | | | | | | | This commit tries to untangle the zoo of diagnostic-related functions in `Tc.Utils.Monad` so that we can have the interfaces mentions only `TcRnMessage`s while we push the creation of these messages upstream. It also ports TcRnMessage diagnostics to use the new API, in particular this commit switch to use TcRnMessage in the external interfaces of the diagnostic functions, and port the old SDoc to be wrapped into TcRnUnknownMessage.
* Remove useless {-# LANGUAGE CPP #-} pragmasSylvain Henry2021-05-121-1/+1
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* Fully remove HsVersions.hSylvain Henry2021-05-121-2/+0
| | | | | | | | | | Replace uses of WARN macro with calls to: warnPprTrace :: Bool -> SDoc -> a -> a Remove the now unused HsVersions.h Bump haddock submodule
* Replace CPP assertions with Haskell functionsSylvain Henry2021-05-121-2/+3
| | | | | | | | | | | | | | | There is no reason to use CPP. __LINE__ and __FILE__ macros are now better replaced with GHC's CallStack. As a bonus, assert error messages now contain more information (function name, column). Here is the mapping table (HasCallStack omitted): * ASSERT: assert :: Bool -> a -> a * MASSERT: massert :: Bool -> m () * ASSERTM: assertM :: m Bool -> m () * ASSERT2: assertPpr :: Bool -> SDoc -> a -> a * MASSERT2: massertPpr :: Bool -> SDoc -> m () * ASSERTM2: assertPprM :: m Bool -> SDoc -> m ()
* Remove flattening variablesRichard Eisenberg2020-12-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch redesigns the flattener to simplify type family applications directly instead of using flattening meta-variables and skolems. The key new innovation is the CanEqLHS type and the new CEqCan constraint (Ct). A CanEqLHS is either a type variable or exactly-saturated type family application; either can now be rewritten using a CEqCan constraint in the inert set. Because the flattener no longer reduces all type family applications to variables, there was some performance degradation if a lengthy type family application is now flattened over and over (not making progress). To compensate, this patch contains some extra optimizations in the flattener, leading to a number of performance improvements. Close #18875. Close #18910. There are many extra parts of the compiler that had to be affected in writing this patch: * The family-application cache (formerly the flat-cache) sometimes stores coercions built from Given inerts. When these inerts get kicked out, we must kick out from the cache as well. (This was, I believe, true previously, but somehow never caused trouble.) Kicking out from the cache requires adding a filterTM function to TrieMap. * This patch obviates the need to distinguish "blocking" coercion holes from non-blocking ones (which, previously, arose from CFunEqCans). There is thus some simplification around coercion holes. * Extra commentary throughout parts of the code I read through, to preserve the knowledge I gained while working. * A change in the pure unifier around unifying skolems with other types. Unifying a skolem now leads to SurelyApart, not MaybeApart, as documented in Note [Binding when looking up instances] in GHC.Core.InstEnv. * Some more use of MCoercion where appropriate. * Previously, class-instance lookup automatically noticed that e.g. C Int was a "unifier" to a target [W] C (F Bool), because the F Bool was flattened to a variable. Now, a little more care must be taken around checking for unifying instances. * Previously, tcSplitTyConApp_maybe would split (Eq a => a). This is silly, because (=>) is not a tycon in Haskell. Fixed now, but there are some knock-on changes in e.g. TrieMap code and in the canonicaliser. * New function anyFreeVarsOf{Type,Co} to check whether a free variable satisfies a certain predicate. * Type synonyms now remember whether or not they are "forgetful"; a forgetful synonym drops at least one argument. This is useful when flattening; see flattenView. * The pattern-match completeness checker invokes the solver. This invocation might need to look through newtypes when checking representational equality. Thus, the desugarer needs to keep track of the in-scope variables to know what newtype constructors are in scope. I bet this bug was around before but never noticed. * Extra-constraints wildcards are no longer simplified before printing. See Note [Do not simplify ConstraintHoles] in GHC.Tc.Solver. * Whether or not there are Given equalities has become slightly subtler. See the new HasGivenEqs datatype. * Note [Type variable cycles in Givens] in GHC.Tc.Solver.Canonical explains a significant new wrinkle in the new approach. * See Note [What might match later?] in GHC.Tc.Solver.Interact, which explains the fix to #18910. * The inert_count field of InertCans wasn't actually used, so I removed it. Though I (Richard) did the implementation, Simon PJ was very involved in design and review. This updates the Haddock submodule to avoid #18932 by adding a type signature. ------------------------- Metric Decrease: T12227 T5030 T9872a T9872b T9872c Metric Increase: T9872d -------------------------
* Split GHC.Driver.TypesSylvain Henry2020-10-291-15/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I was working on making DynFlags stateless (#17957), especially by storing loaded plugins into HscEnv instead of DynFlags. It turned out to be complicated because HscEnv is in GHC.Driver.Types but LoadedPlugin isn't: it is in GHC.Driver.Plugins which depends on GHC.Driver.Types. I didn't feel like introducing yet another hs-boot file to break the loop. Additionally I remember that while we introduced the module hierarchy (#13009) we talked about splitting GHC.Driver.Types because it contained various unrelated types and functions, but we never executed. I didn't feel like making GHC.Driver.Types bigger with more unrelated Plugins related types, so finally I bit the bullet and split GHC.Driver.Types. As a consequence this patch moves a lot of things. I've tried to put them into appropriate modules but nothing is set in stone. Several other things moved to avoid loops. * Removed Binary instances from GHC.Utils.Binary for random compiler things * Moved Typeable Binary instances into GHC.Utils.Binary.Typeable: they import a lot of things that users of GHC.Utils.Binary don't want to depend on. * put everything related to Units/Modules under GHC.Unit: GHC.Unit.Finder, GHC.Unit.Module.{ModGuts,ModIface,Deps,etc.} * Created several modules under GHC.Types: GHC.Types.Fixity, SourceText, etc. * Split GHC.Utils.Error (into GHC.Types.Error) * Finally removed GHC.Driver.Types Note that this patch doesn't put loaded plugins into HscEnv. It's left for another patch. Bump haddock submodule
* Allow multiple case branches to have a higher rank typeSimon Peyton Jones2020-07-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | As #18412 points out, it should be OK for multiple case alternatives to have a higher rank type, provided they are all the same. This patch implements that change. It sweeps away GHC.Tc.Gen.Match.tauifyMultipleBranches, and friends, replacing it with an enhanced version of fillInferResult. The basic change to fillInferResult is to permit the case in which another case alternative has already filled in the result; and in that case simply unify. It's very simple actually. See the new Note [fillInferResult] in TcMType Other refactoring: - Move all the InferResult code to one place, in GHC.Tc.Utils.TcMType (previously some of it was in Unify) - Move tcInstType and friends from TcMType to Instantiate, where it more properly belongs. (TCMType was getting very long.)
* Improve handling of data type return kindswip/T18300Simon Peyton Jones2020-07-031-30/+4
| | | | | | | | | | | | | | | | | | Following a long conversation with Richard, this patch tidies up the handling of return kinds for data/newtype declarations (vanilla, family, and instance). I have substantially edited the Notes in TyCl, so they would bear careful reading. Fixes #18300, #18357 In GHC.Tc.Instance.Family.newFamInst we were checking some Lint-like properties with ASSSERT. Instead Richard and I have added a proper linter for axioms, and called it from lintGblEnv, which in turn is called in tcRnModuleTcRnM New tests (T18300, T18357) cause an ASSERT failure in HEAD.
* Clean up haddock hyperlinks of GHC.* (part2)Takenobu Tani2020-06-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | This updates haddock comments only. This patch focuses to update for hyperlinks in GHC API's haddock comments, because broken links especially discourage newcomers. This includes the following hierarchies: - GHC.Iface.* - GHC.Llvm.* - GHC.Rename.* - GHC.Tc.* - GHC.HsToCore.* - GHC.StgToCmm.* - GHC.CmmToAsm.* - GHC.Runtime.* - GHC.Unit.* - GHC.Utils.* - GHC.SysTools.*
* Unit: split and rename modulesSylvain Henry2020-04-301-1/+1
| | | | | | | Introduce GHC.Unit.* hierarchy for everything concerning units, packages and modules. Update Haddock submodule
* Refactoring unit management codeSylvain Henry2020-04-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Over the years the unit management code has been modified a lot to keep up with changes in Cabal (e.g. support for several library components in the same package), to integrate BackPack, etc. I found it very hard to understand as the terminology wasn't consistent, was referring to past concepts, etc. The terminology is now explained as clearly as I could in the Note "About Units" and the code is refactored to reflect it. ------------------- Many names were misleading: UnitId is not an Id but could be a virtual unit (an indefinite one instantiated on the fly), IndefUnitId constructor may contain a definite instantiated unit, etc. * Rename IndefUnitId into InstantiatedUnit * Rename IndefModule into InstantiatedModule * Rename UnitId type into Unit * Rename IndefiniteUnitId constructor into VirtUnit * Rename DefiniteUnitId constructor into RealUnit * Rename packageConfigId into mkUnit * Rename getPackageDetails into unsafeGetUnitInfo * Rename InstalledUnitId into UnitId Remove references to misleading ComponentId: a ComponentId is just an indefinite unit-id to be instantiated. * Rename ComponentId into IndefUnitId * Rename ComponentDetails into UnitPprInfo * Fix display of UnitPprInfo with empty version: this is now used for units dynamically generated by BackPack Generalize several types (Module, Unit, etc.) so that they can be used with different unit identifier types: UnitKey, UnitId, Unit, etc. * GenModule: Module, InstantiatedModule and InstalledModule are now instances of this type * Generalize DefUnitId, IndefUnitId, Unit, InstantiatedUnit, PackageDatabase Replace BackPack fake "hole" UnitId by a proper HoleUnit constructor. Add basic support for UnitKey. They should be used more in the future to avoid mixing them up with UnitId as we do now. Add many comments. Update Haddock submodule
* Modules: Utils and Data (#13009)Sylvain Henry2020-04-261-7/+7
| | | | | | | Update Haddock submodule Metric Increase: haddock.compiler
* Modules: type-checker (#13009)Sylvain Henry2020-04-071-0/+1056
Update Haddock submodule