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* Improve pretty-printer defaulting logic (#19361)Krzysztof Gogolewski2021-09-171-0/+1
| | | | | | When determining whether to default a RuntimeRep or Multiplicity variable, use isMetaTyVar to distinguish between metavariables (which can be hidden) and skolems (which cannot).
* Driver rework pt3: the upsweepMatthew Pickering2021-08-181-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch specifies and simplifies the module cycle compilation in upsweep. How things work are described in the Note [Upsweep] Note [Upsweep] ~~~~~~~~~~~~~~ Upsweep takes a 'ModuleGraph' as input, computes a build plan and then executes the plan in order to compile the project. The first step is computing the build plan from a 'ModuleGraph'. The output of this step is a `[BuildPlan]`, which is a topologically sorted plan for how to build all the modules. ``` data BuildPlan = SingleModule ModuleGraphNode -- A simple, single module all alone but *might* have an hs-boot file which isn't part of a cycle | ResolvedCycle [ModuleGraphNode] -- A resolved cycle, linearised by hs-boot files | UnresolvedCycle [ModuleGraphNode] -- An actual cycle, which wasn't resolved by hs-boot files ``` The plan is computed in two steps: Step 1: Topologically sort the module graph without hs-boot files. This returns a [SCC ModuleGraphNode] which contains cycles. Step 2: For each cycle, topologically sort the modules in the cycle *with* the relevant hs-boot files. This should result in an acyclic build plan if the hs-boot files are sufficient to resolve the cycle. The `[BuildPlan]` is then interpreted by the `interpretBuildPlan` function. * `SingleModule nodes` are compiled normally by either the upsweep_inst or upsweep_mod functions. * `ResolvedCycles` need to compiled "together" so that the information which ends up in the interface files at the end is accurate (and doesn't contain temporary information from the hs-boot files.) - During the initial compilation, a `KnotVars` is created which stores an IORef TypeEnv for each module of the loop. These IORefs are gradually updated as the loop completes and provide the required laziness to typecheck the module loop. - At the end of typechecking, all the interface files are typechecked again in the retypecheck loop. This time, the knot-tying is done by the normal laziness based tying, so the environment is run without the KnotVars. * UnresolvedCycles are indicative of a proper cycle, unresolved by hs-boot files and are reported as an error to the user. The main trickiness of `interpretBuildPlan` is deciding which version of a dependency is visible from each module. For modules which are not in a cycle, there is just one version of a module, so that is always used. For modules in a cycle, there are two versions of 'HomeModInfo'. 1. Internal to loop: The version created whilst compiling the loop by upsweep_mod. 2. External to loop: The knot-tied version created by typecheckLoop. Whilst compiling a module inside the loop, we need to use the (1). For a module which is outside of the loop which depends on something from in the loop, the (2) version is used. As the plan is interpreted, which version of a HomeModInfo is visible is updated by updating a map held in a state monad. So after a loop has finished being compiled, the visible module is the one created by typecheckLoop and the internal version is not used again. This plan also ensures the most important invariant to do with module loops: > If you depend on anything within a module loop, before you can use the dependency, the whole loop has to finish compiling. The end result of `interpretBuildPlan` is a `[MakeAction]`, which are pairs of `IO a` actions and a `MVar (Maybe a)`, somewhere to put the result of running the action. This list is topologically sorted, so can be run in order to compute the whole graph. As well as this `interpretBuildPlan` also outputs an `IO [Maybe (Maybe HomeModInfo)]` which can be queried at the end to get the result of all modules at the end, with their proper visibility. For example, if any module in a loop fails then all modules in that loop will report as failed because the visible node at the end will be the result of retypechecking those modules together. Along the way we also fix a number of other bugs in the driver: * Unify upsweep and parUpsweep. * Fix #19937 (static points, ghci and -j) * Adds lots of module loop tests due to Divam. Also related to #20030 Co-authored-by: Divam Narula <dfordivam@gmail.com> ------------------------- Metric Decrease: T10370 -------------------------
* mkUnique refactoring (#18362)Aditya Gupta2020-08-221-0/+7
| | | | | Move uniqFromMask from Unique.Supply to Unique. Move the the functions that call mkUnique from Unique to Builtin.Uniques
* Various performance improvementsKrzysztof Gogolewski2020-06-171-7/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This implements several general performance improvements to GHC, to offset the effect of the linear types change. General optimisations: - Add a `coreFullView` function which iterates `coreView` on the head. This avoids making function recursive solely because the iterate `coreView` themselves. As a consequence, this functions can be inlined, and trigger case-of-known constructor (_e.g._ `kindRep_maybe`, `isLiftedRuntimeRep`, `isMultiplicityTy`, `getTyVar_maybe`, `splitAppTy_maybe`, `splitFunType_maybe`, `tyConAppTyCon_maybe`). The common pattern about all these functions is that they are almost always used as views, and immediately consumed by a case expression. This commit also mark them asx `INLINE`. - In `subst_ty` add a special case for nullary `TyConApp`, which avoid allocations altogether. - Use `mkTyConApp` in `subst_ty` for the general `TyConApp`. This required quite a bit of module shuffling. case. `myTyConApp` enforces crucial sharing, which was lost during substitution. See also !2952 . - Make `subst_ty` stricter. - In `eqType` (specifically, in `nonDetCmpType`), add a special case, tested first, for the very common case of nullary `TyConApp`. `nonDetCmpType` has been made `INLINE` otherwise it is actually a regression. This is similar to the optimisations in !2952. Linear-type specific optimisations: - Use `tyConAppTyCon_maybe` instead of the more complex `eqType` in the definition of the pattern synonyms `One` and `Many`. - Break the `hs-boot` cycles between `Multiplicity.hs` and `Type.hs`: `Multiplicity` now import `Type` normally, rather than from the `hs-boot`. This way `tyConAppTyCon_maybe` can inline properly in the `One` and `Many` pattern synonyms. - Make `updateIdTypeAndMult` strict in its type and multiplicity - The `scaleIdBy` gets a specialised definition rather than being an alias to `scaleVarBy` - `splitFunTy_maybe` is given the type `Type -> Maybe (Mult, Type, Type)` instead of `Type -> Maybe (Scaled Type, Type)` - Remove the `MultMul` pattern synonym in favour of a view `isMultMul` because pattern synonyms appear not to inline well. - in `eqType`, in a `FunTy`, compare multiplicities last: they are almost always both `Many`, so it helps failing faster. - Cache `manyDataConTy` in `mkTyConApp`, to make sure that all the instances of `TyConApp ManyDataConTy []` are physically the same. This commit has been authored by * Richard Eisenberg * Krzysztof Gogolewski * Arnaud Spiwack Metric Decrease: haddock.base T12227 T12545 T12990 T1969 T3064 T5030 T9872b Metric Increase: haddock.base haddock.Cabal haddock.compiler T12150 T12234 T12425 T12707 T13035 T13056 T15164 T16190 T18304 T1969 T3064 T3294 T5631 T5642 T5837 T6048 T9020 T9233 T9675 T9872a T9961 WWRec
* Modules: Utils and Data (#13009)Sylvain Henry2020-04-261-2/+2
| | | | | | | Update Haddock submodule Metric Increase: haddock.compiler
* Modules: Types (#13009)Sylvain Henry2020-03-291-0/+14
Update Haddock submodule Metric Increase: haddock.compiler