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* Fix order of PrelRuleBen Gamari2017-09-011-1/+1
| | | | | | | | | | | | Test Plan: Added testcase in D3905. Reviewers: austin Subscribers: angerman, rwbarton, thomie GHC Trac Issues: #14178 Differential Revision: https://phabricator.haskell.org/D3904
* A bunch of typofixesGabor Greif2017-07-311-1/+1
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* Re-engineer caseRules to add tagToEnum/dataToTagSimon Peyton Jones2017-04-281-82/+149
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | See Note [Scrutinee Constant Folding] in SimplUtils * Add cases for tagToEnum and dataToTag. This is the main new bit. It allows the simplifier to remove the pervasive uses of case tagToEnum (a > b) of False -> e1 True -> e2 and replace it by the simpler case a > b of DEFAULT -> e1 1# -> e2 See Note [caseRules for tagToEnum] and Note [caseRules for dataToTag] in PrelRules. * This required some changes to the API of caseRules, and hence to code in SimplUtils. See Note [Scrutinee Constant Folding] in SimplUtils. * Avoid duplication of work in the (unusual) case of case BIG + 3# of b DEFAULT -> e1 6# -> e2 Previously we got case BIG of DEFAULT -> let b = BIG + 3# in e1 3# -> let b = 6# in e2 Now we get case BIG of b# DEFAULT -> let b = b' + 3# in e1 3# -> let b = 6# in e2 * Avoid duplicated code in caseRules A knock-on refactoring: * Move Note [Word/Int underflow/overflow] to Literal, as documentation to accompany mkMachIntWrap etc; and get rid of PrelRuls.intResult' in favour of mkMachIntWrap
* No join-point from an INLINE function with wrong aritySimon Peyton Jones2017-03-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | The main payload of this patch is NOT to make a join-point from a function with an INLINE pragma and the wrong arity; see Note [Join points and INLINE pragmas] in CoreOpt. This is what caused Trac #13413. But we must do the exact same thing in simpleOptExpr, which drove me to the following refactoring: * Move simpleOptExpr and simpleOptPgm from CoreSubst to a new module CoreOpt along with a few others (exprIsConApp_maybe, pushCoArg, etc) This eliminates a module loop altogether (delete CoreArity.hs-boot), and stops CoreSubst getting too huge. * Rename Simplify.matchOrConvertToJoinPoint to joinPointBinding_maybe Move it to the new CoreOpt Use it in simpleOptExpr as well as in Simplify * Define CoreArity.joinRhsArity and use it
* Ensure that scrutinee constant folding wraps numbersSylvain Henry2017-01-231-31/+61
| | | | | | | | | | | | | | Test Plan: T13172 Reviewers: rwbarton, simonpj, austin, bgamari Reviewed By: simonpj, bgamari Subscribers: simonpj, thomie Differential Revision: https://phabricator.haskell.org/D3009 GHC Trac Issues: #13172
* Allow top-level string literals in Core (#8472)Takano Akio2017-01-201-18/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This commits relaxes the invariants of the Core syntax so that a top-level variable can be bound to a primitive string literal of type Addr#. This commit: * Relaxes the invatiants of the Core, and allows top-level bindings whose type is Addr# as long as their RHS is either a primitive string literal or another variable. * Allows the simplifier and the full-laziness transformer to float out primitive string literals to the top leve. * Introduces the new StgGenTopBinding type to accomodate top-level Addr# bindings. * Introduces a new type of labels in the object code, with the suffix "_bytes", for exported top-level Addr# bindings. * Makes some built-in rules more robust. This was necessary to keep them functional after the above changes. This is a continuation of D2554. Rebasing notes: This had two slightly suspicious performance regressions: * T12425: bytes allocated regressed by roughly 5% * T4029: bytes allocated regressed by a bit over 1% * T13035: bytes allocated regressed by a bit over 5% These deserve additional investigation. Rebased by: bgamari. Test Plan: ./validate --slow Reviewers: goldfire, trofi, simonmar, simonpj, austin, hvr, bgamari Reviewed By: trofi, simonpj, bgamari Subscribers: trofi, simonpj, gridaphobe, thomie Differential Revision: https://phabricator.haskell.org/D2605 GHC Trac Issues: #8472
* Scrutinee Constant FoldingSylvain Henry2016-12-091-1/+56
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch introduces new rules to perform constant folding through case-expressions. E.g., ``` case t -# 10# of _ { ===> case t of _ { 5# -> e1 15# -> e1 8# -> e2 18# -> e2 DEFAULT -> e DEFAULT -> e ``` The initial motivation is that it allows "Merge Nested Cases" optimization to kick in and to further simplify the code (see Trac #12877). Currently we recognize the following operations for Word# and Int#: Add, Sub, Xor, Not and Negate (for Int# only). Test Plan: validate Reviewers: simonpj, austin, bgamari Reviewed By: simonpj, bgamari Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D2762 GHC Trac Issues: #12877
* Turn divInt# and modInt# into bitwise operations when possibleTakano Akio2016-09-051-1/+20
| | | | | | | | | | | | | | | | | | | This implements #5615 for divInt# and modInt#. I also included rules to do constant-folding when the both arguments are known. Test Plan: validate Reviewers: austin, simonmar, bgamari Reviewed By: bgamari Subscribers: hvr, thomie Differential Revision: https://phabricator.haskell.org/D2486 GHC Trac Issues: #5615
* PrelRules: Fix constant folding for WordRemOpBen Gamari2016-03-201-1/+6
| | | | | | | | | | | | | | Test Plan: Validate with testcase in D2002 Reviewers: austin, simonpj Reviewed By: simonpj Subscribers: simonpj, thomie Differential Revision: https://phabricator.haskell.org/D2004 GHC Trac Issues: #11702
* Replace calls to `ptext . sLit` with `text`Jan Stolarek2016-01-181-1/+1
| | | | | | | | | | | | | | | | | | | | Summary: In the past the canonical way for constructing an SDoc string literal was the composition `ptext . sLit`. But for some time now we have function `text` that does the same. Plus it has some rules that optimize its runtime behaviour. This patch takes all uses of `ptext . sLit` in the compiler and replaces them with calls to `text`. The main benefits of this patch are clener (shorter) code and less dependencies between module, because many modules now do not need to import `FastString`. I don't expect any performance benefits - we mostly use SDocs to report errors and it seems there is little to be gained here. Test Plan: ./validate Reviewers: bgamari, austin, goldfire, hvr, alanz Subscribers: goldfire, thomie, mpickering Differential Revision: https://phabricator.haskell.org/D1784
* Canonicalise `MonadPlus` instancesHerbert Valerio Riedel2016-01-011-6/+4
| | | | | | | This refactoring exploits the fact that since AMP, in most cases, `instance MonadPlus` can be automatically derived from the respective `Alternative` instance. This is because `MonadPlus`'s default method implementations are fully defined in terms of `Alternative(empty, (<>))`.
* Remove some redundant definitions/constraintsHerbert Valerio Riedel2015-12-311-1/+0
| | | | | | Starting with GHC 7.10 and base-4.8, `Monad` implies `Applicative`, which allows to simplify some definitions to exploit the superclass relationship. This a first refactoring to that end.
* Drop pre-AMP compatibility CPP conditionalsHerbert Valerio Riedel2015-12-311-4/+0
| | | | | | | | | | | | Since GHC 8.1/8.2 only needs to be bootstrap-able by GHC 7.10 and GHC 8.0 (and GHC 8.2), we can now finally drop all that pre-AMP compatibility CPP-mess for good! Reviewers: austin, goldfire, bgamari Subscribers: goldfire, thomie, erikd Differential Revision: https://phabricator.haskell.org/D1724
* Add kind equalities to GHC.Richard Eisenberg2015-12-111-28/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This implements the ideas originally put forward in "System FC with Explicit Kind Equality" (ICFP'13). There are several noteworthy changes with this patch: * We now have casts in types. These change the kind of a type. See new constructor `CastTy`. * All types and all constructors can be promoted. This includes GADT constructors. GADT pattern matches take place in type family equations. In Core, types can now be applied to coercions via the `CoercionTy` constructor. * Coercions can now be heterogeneous, relating types of different kinds. A coercion proving `t1 :: k1 ~ t2 :: k2` proves both that `t1` and `t2` are the same and also that `k1` and `k2` are the same. * The `Coercion` type has been significantly enhanced. The documentation in `docs/core-spec/core-spec.pdf` reflects the new reality. * The type of `*` is now `*`. No more `BOX`. * Users can write explicit kind variables in their code, anywhere they can write type variables. For backward compatibility, automatic inference of kind-variable binding is still permitted. * The new extension `TypeInType` turns on the new user-facing features. * Type families and synonyms are now promoted to kinds. This causes trouble with parsing `*`, leading to the somewhat awkward new `HsAppsTy` constructor for `HsType`. This is dispatched with in the renamer, where the kind `*` can be told apart from a type-level multiplication operator. Without `-XTypeInType` the old behavior persists. With `-XTypeInType`, you need to import `Data.Kind` to get `*`, also known as `Type`. * The kind-checking algorithms in TcHsType have been significantly rewritten to allow for enhanced kinds. * The new features are still quite experimental and may be in flux. * TODO: Several open tickets: #11195, #11196, #11197, #11198, #11203. * TODO: Update user manual. Tickets addressed: #9017, #9173, #7961, #10524, #8566, #11142. Updates Haddock submodule.
* MonadFail proposal, phase 1David Luposchainsky2015-11-171-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | This implements phase 1 of the MonadFail proposal (MFP, #10751). - MonadFail warnings are all issued as desired, tunable with two new flags - GHC was *not* made warning-free with `-fwarn-missing-monadfail-warnings` (but it's disabled by default right now) Credits/thanks to - Franz Thoma, whose help was crucial to implementing this - My employer TNG Technology Consulting GmbH for partially funding us for this work Reviewers: goldfire, austin, #core_libraries_committee, hvr, bgamari, fmthoma Reviewed By: hvr, bgamari, fmthoma Subscribers: thomie Projects: #ghc Differential Revision: https://phabricator.haskell.org/D1248 GHC Trac Issues: #10751
* Make Monad/Applicative instances MRP-friendlyHerbert Valerio Riedel2015-10-171-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | This patch refactors pure/(*>) and return/(>>) in MRP-friendly way, i.e. such that the explicit definitions for `return` and `(>>)` match the MRP-style default-implementation, i.e. return = pure and (>>) = (*>) This way, e.g. all `return = pure` definitions can easily be grepped and removed in GHC 8.1; Test Plan: Harbormaster Reviewers: goldfire, alanz, bgamari, quchen, austin Reviewed By: quchen, austin Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D1312
* Fix treatment of -0.0Ben Gamari2015-10-021-51/+74
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Here we fix a few mis-optimizations that could occur in code with floating point comparisons with -0.0. These issues arose from our insistence on rewriting equalities into case analyses and the simplifier's ignorance of floating-point semantics. For instance, in Trac #10215 (and the similar issue Trac #9238) we turned `ds == 0.0` into a case analysis, ``` case ds of __DEFAULT -> ... 0.0 -> ... ``` Where the second alternative matches where `ds` is +0.0 and *also* -0.0. However, the simplifier doesn't realize this and will introduce a local inlining of `ds = -- +0.0` as it believes this is the only value that matches this pattern. Instead of teaching the simplifier about floating-point semantics we simply prohibit case analysis on floating-point scrutinees and keep this logic in the comparison primops, where it belongs. We do several things here, - Add test cases from relevant tickets - Clean up a bit of documentation - Desugar literal matches against floats into applications of the appropriate equality primitive instead of case analysis - Add a CoreLint to ensure we don't pattern match on floats in Core Test Plan: validate with included testcases Reviewers: goldfire, simonpj, austin Subscribers: thomie Differential Revision: https://phabricator.haskell.org/D1061 GHC Trac Issues: #10215, #9238
* Add constant-folding rule for Data.Bits.bitBen Gamari2015-09-231-8/+31
| | | | | | | | | | | This adds a constant-folding rule for `Integer`'s implementation of `bit` and fixes the `T8832` testcase. Fixes #8832. Reviewed By: simonpj, austin Differential Revision: https://phabricator.haskell.org/D1255 GHC Trac Issues: #8832
* Refactor tuple constraintsSimon Peyton Jones2015-05-181-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make tuple constraints be handled by a perfectly ordinary type class, with the component constraints being the superclasses: class (c1, c2) => (c2, c2) This change was provoked by #10359 inability to re-use a given tuple constraint as a whole #9858 confusion between term tuples and constraint tuples but it's generally a very nice simplification. We get rid of - In Type, the TuplePred constructor of PredTree, and all the code that dealt with TuplePreds - In TcEvidence, the constructors EvTupleMk, EvTupleSel See Note [How tuples work] in TysWiredIn. Of course, nothing is ever entirely simple. This one proved quite fiddly. - I did quite a bit of renaming, which makes this patch touch a lot of modules. In partiuclar tupleCon -> tupleDataCon. - I made constraint tuples known-key rather than wired-in. This is different to boxed/unboxed tuples, but it proved awkward to have all the superclass selectors wired-in. Easier just to use the standard mechanims. - While I was fiddling with known-key names, I split the TH Name definitions out of DsMeta into a new module THNames. That meant that the known-key names can all be gathered in PrelInfo, without causing module loops. - I found that the parser was parsing an import item like T( .. ) as a *data constructor* T, and then using setRdrNameSpace to fix it. Stupid! So I changed the parser to parse a *type constructor* T, which means less use of setRdrNameSpace. I also improved setRdrNameSpace to behave better on Exact Names. Largely on priciple; I don't think it matters a lot. - When compiling a data type declaration for a wired-in thing like tuples (,), or lists, we don't really need to look at the declaration. We have the wired-in thing! And not doing so avoids having to line up the uniques for data constructor workers etc. See Note [Declarations for wired-in things] - I found that FunDeps.oclose wasn't taking superclasses into account; easily fixed. - Some error message refactoring for invalid constraints in TcValidity - Haddock needs to absorb the change too; so there is a submodule update
* Revert multiple commitsAustin Seipp2015-05-141-3/+3
| | | | | | | | | | | | | | | | | | | | This reverts multiple commits from Simon: - 04a484eafc9eb9f8774b4bdd41a5dc6c9f640daf Test Trac #10359 - a9ccd37add8315e061c02e5bf26c08f05fad9ac9 Test Trac #10403 - c0aae6f699cbd222d826d0b8d78d6cb3f682079e Test Trac #10248 - eb6ca851f553262efe0824b8dcbe64952de4963d Make the "matchable-given" check happen first - ca173aa30467a0b1023682d573fcd94244d85c50 Add a case to checkValidTyCon - 51cbad15f86fca1d1b0e777199eb1079a1b64d74 Update haddock submodule - 6e1174da5b8e0b296f5bfc8b39904300d04eb5b7 Separate transCloVarSet from fixVarSet - a8493e03b89f3b3bfcdb6005795de050501f5c29 Fix imports in HscMain (stage2) - a154944bf07b2e13175519bafebd5a03926bf105 Two wibbles to fix the build - 5910a1bc8142b4e56a19abea104263d7bb5c5d3f Change in capitalisation of error msg - 130e93aab220bdf14d08028771f83df210da340b Refactor tuple constraints - 8da785d59f5989b9a9df06386d5bd13f65435bc0 Delete commented-out line These break the build by causing Haddock to fail mysteriously when trying to examine GHC.Prim it seems.
* Refactor tuple constraintsSimon Peyton Jones2015-05-131-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make tuple constraints be handled by a perfectly ordinary type class, with the component constraints being the superclasses: class (c1, c2) => (c2, c2) This change was provoked by #10359 inability to re-use a given tuple constraint as a whole #9858 confusion between term tuples and constraint tuples but it's generally a very nice simplification. We get rid of - In Type, the TuplePred constructor of PredTree, and all the code that dealt with TuplePreds - In TcEvidence, the constructors EvTupleMk, EvTupleSel See Note [How tuples work] in TysWiredIn. Of course, nothing is ever entirely simple. This one proved quite fiddly. - I did quite a bit of renaming, which makes this patch touch a lot of modules. In partiuclar tupleCon -> tupleDataCon. - I made constraint tuples known-key rather than wired-in. This is different to boxed/unboxed tuples, but it proved awkward to have all the superclass selectors wired-in. Easier just to use the standard mechanims. - While I was fiddling with known-key names, I split the TH Name definitions out of DsMeta into a new module THNames. That meant that the known-key names can all be gathered in PrelInfo, without causing module loops. - I found that the parser was parsing an import item like T( .. ) as a *data constructor* T, and then using setRdrNameSpace to fix it. Stupid! So I changed the parser to parse a *type constructor* T, which means less use of setRdrNameSpace. I also improved setRdrNameSpace to behave better on Exact Names. Largely on priciple; I don't think it matters a lot. - When compiling a data type declaration for a wired-in thing like tuples (,), or lists, we don't really need to look at the declaration. We have the wired-in thing! And not doing so avoids having to line up the uniques for data constructor workers etc. See Note [Declarations for wired-in things] - I found that FunDeps.oclose wasn't taking superclasses into account; easily fixed. - Some error message refactoring for invalid constraints in TcValidity
* Pretty-print # on unboxed literals in coreThomas Miedema2015-03-031-5/+5
| | | | | | | | | | | | | | | | | | Summary: Ticket #10104 dealt with showing the '#'s on types with unboxed fields. This commit pretty prints the '#'s on unboxed literals in core output. Test Plan: simplCore/should_compile/T8274 Reviewers: jstolarek, simonpj, austin Reviewed By: simonpj, austin Subscribers: simonpj, thomie Differential Revision: https://phabricator.haskell.org/D678 GHC Trac Issues: #8274
* Replace .lhs with .hs in compiler commentsYuri de Wit2015-02-091-2/+2
| | | | | | | | | | | | | | Summary: It looks like during .lhs -> .hs switch the comments were not updated. So doing exactly that. Reviewers: austin, jstolarek, hvr, goldfire Reviewed By: austin, jstolarek Subscribers: thomie, goldfire Differential Revision: https://phabricator.haskell.org/D621 GHC Trac Issues: #9986
* compiler: de-lhs prelude/Austin Seipp2014-12-031-0/+1322
Signed-off-by: Austin Seipp <austin@well-typed.com>
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